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Sample records for beta-lactamase producing klebsiella

  1. Prevalence of Extended –Spectrum-Beta-Lactamase-Producing Klebsiella Pneumonia Isolates from Clinical Samples

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    Alizade, H. (MSc

    2014-06-01

    Full Text Available Background and Objective: Klebsiella pneumonia (K.pneumonia is one of the common causes of nosocomial infections. The aim of this research was to determine the prevalence of beta-lactamase genes and phenotypic confirmation of extended–spectrum-beta-lactamase (ESBL producing K.pneumonia isolates from clinical samples. Material and Methods: In this study, 122 K.pneumonia were isolated from clinical specimens of Khoramabad city and were confirmed by standard bacteriological tests. The presence of ESBL enzymes was detected by combined disk diffusion method. PCR assay with specific primers was used to determine blaSHV, blaTEM, blaCTX-15 and blaCTX-M genes in the confirmed isolates. Results: of 122 K.pneumonia isolates, 78 (64.18% were positive for ESBL, using disk diffusion method. According to antibiogram results, 10.65% of isolates were resistant to cefotaxime, 3.27% to ceftazidime and 68.03% to both antibiotics. Ninety isolates (64.18% considered as ESBLs isolates, at the same time, with being resistant to cefotaxime and ceftazidime were also sensitive to cefotaxime-clavulanic acid and ceftazidime-clavulanic acid. In PCR assays, blaCTX-15, blaSHV, blaCTX-M and blaTEM genes were detected in 78.68%, 40.16%, 26.22% and 22.13% of isolates, respectively. Ten resistant patterns of genes were detected. Conclusion: The significance percentage of antibiotic resistant genes of K.pneumonia isolates from clinical samples in Khoramabad city had ESBLs genes; CTX-M category was the most prevalent encoding genes of these enzymes. Keywords: Klebsiella Pneumonia, Extended-Spectrum Beta-Lactamase, Antibiotic Resistance

  2. PREVALENCE OF EXTENDED SPECTRUM BETA LACTAMASES PRODUCING KLEBSIELLA PNEUMONIAE ISOLATED AT GOVERNM ENT MEDICAL COLLEGE, NANDED

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    Vivek

    2013-01-01

    Full Text Available ABSTRACT: PURPOSE :- The purpose of this study was to know the prevalenc e of Extended Spectrum beta lactamases (ESBL in Klebsiella pneumon iae isolated from various clinical specimens. METHODS :- A present study was conducted at Dr. Shankarrao C havan Government Medical College, Nanded between January 2011 – Dec ember 2011. A total number of 201 various clinical samples were processed during the st udy. 91 strains of Klebsiella pneumoniae were isolated. They were studied for ESBL production by screening test, CLSI disc diffusion method & phenotypic confirmation by disc potentiation test. RESULT :- Out of 91 strains, 71 were found positive for ESBL production by screening test. Out of 71 strains 59 were confirmed by disc potentiation test. So out of 91 strains 59 ( 64.8% were confirmed as ESBL producers. Among the ESBL producer Klebsiella pneumoniae, 11(18. 64% were sensitive to Cefotaxime, 06(10.16% to Ceftriaxone & 10(16.94% to Ceftazidi me by routine Kirby Bauer disc diffusion method. All the Klebsiella pneumoniae isolates were sensitive to Imipenem. Resistance against Ampicillin (10ug is 100%, Ciprofloxacin (5ug is 93. 22%, Gentamicin (10ug is 88.13%, Tetracycline (30ug is 72.9% and Amikacin (30ug is 18.64%. CONCLUSION : Our study shows presence of ESBL producer Klebsiella pneumoniae in cli nical specimens and their prevalence is 64.8%. The routine antimicrobial sensitivity test m ay fail to detect ESBL. Detection of ESBL production should be carried out as a routine in dia gnostic laboratories by disc potentiation test as it is a simple and cost effective test. Antibioti cs resistance is significantly more prevalent in ESBL positive isolates as compared to ESBL negative

  3. Emergence of serotype K1 Klebsiella pneumoniae ST23 strains co-producing the plasmid-mediated AmpC beta-lactamase DHA-1 and an extended-spectrum beta-lactamase in Korea

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    Hae Suk Cheong

    2016-11-01

    Full Text Available Abstract Background Serotype K1 Klebsiella pneumoniae has emerged as an important community pathogen causing various infections, including liver abscesses. Although serotype K1 K. pneumoniae community isolates have been reported as susceptible to most classes of antimicrobial agents, a few cases of infection caused by extended-spectrum beta-lactamase (ESBL-producing serotype K1 K. pneumoniae have recently been reported in Asian countries. We identified three ESBL-producing strains of serotype K1 K. pneumoniae and conducted a molecular characterization of their drug resistance. Methods Three ESBL-producing serotype K1 K. pneumoniae ST23 strains were identified from strains in the Asian Bacterial Bank. Antimicrobial susceptibility testing was performed using the broth microdilution method, and ESBL production was tested by the double-disk synergy test and a confirmatory test. PCR was performed to detect the genes for plasmid-mediated ESBL and AmpC beta-lactamases. Results All three strains were resistant to cefotaxime, ceftazidime, and piperacillin/tazobactam, and all were determined to be ESBL-producers. No known ESBL genes, including bla SHV, bla TEM, bla CTX-M, bla GES, bla PER, and bla VEB, were detected among the three strains. Of all plasmid-mediated AmpC beta-lactamase (PAB genes, including bla DHA-1, bla CMY, bla FOX, and bla MOX, the bla DHA-1 gene was detected in two of the strains. The PFGE patterns revealed that the two isolates carrying bla DHA-1 were closely related (84% similarity. Conclusions No ESBL genes were detected among three ESBL-producing serotype K1 K. pneumoniae ST23 strains. Two strains contained the PAB gene bla DHA-1. The emergence of resistant strains of community-origin serotype K1 K. pneumoniae has important implications for effective treatment and infection control practices.

  4. Integron mediated multidrug resistance in extended spectrum beta-lactamase producing clinical isolates of Klebsiella pneumoniae

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    Maryam Mobarak-Qamsari

    2013-09-01

    Full Text Available The present study describes integron mediated multiple antibiotic resistance in extended-spectrum β-lactamase producing clinical isolates of Klebsiella pneumoniae. One hundred and four clinical isolates of K. pneumoniae from two Iranian hospitals were screened for extended-spectrum β-lactamase production and susceptibility of the extended-spectrum β-lactamase producing isolates was determined to 17 antibiotics by disc diffusion. Presence of integron classes 1, 2 and 3 was detected by PCR and integrase specific primers. Isolates harboring class 1 integron were then screened for variable regions using PCR. Fifty isolates (48% produced extended-spectrum β-lactamases among which, 22 (44% harbored class 1, 3 (6% carried class 2 and none contained class 3 integons. Integron carriage was significantly associated with higher rates of multiple antibiotic resistance in extended-spectrum β-lactamase producing clinical isolates of K. pneumoniae. Integron harboring isolates were more resistant to aztreonam (51.3%, ceftazidime (42.6%, cefotaxime (43.3%, cefepime (24.6%, kanamycin (43.2%, tobramycin (30.7%, norfloxcacin (32% and spectinomycin (25.6% compared to the organisms without integrons. On the other hand, resistance to nitrofurantoin and streptomycin was significantly higher among the integron negative isolates. PCR amplification of class1 integron variable regions revealed 9 different sized DNA fragments and isolates with similar profiles for class 1 integron variable regions showed the same antibiotic resistance phenotypes.

  5. Integron mediated multidrug resistance in extended spectrum beta-lactamase producing clinical isolates of Klebsiella pneumoniae

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    Mobarak-Qamsari, Maryam; Ashayeri-Panah, Mitra; Eftekhar, Freshteh; Feizabadi, Mohammad Mehdi

    2013-01-01

    The present study describes integron mediated multiple antibiotic resistance in extended-spectrum β-lactamase producing clinical isolates of Klebsiella pneumoniae. One hundred and four clinical isolates of K. pneumoniae from two Iranian hospitals were screened for extended-spectrum β-lactamase production and susceptibility of the extended-spectrum β-lactamase producing isolates was determined to 17 antibiotics by disc diffusion. Presence of integron classes 1, 2 and 3 was detected by PCR and integrase specific primers. Isolates harboring class 1 integron were then screened for variable regions using PCR. Fifty isolates (48%) produced extended-spectrum β-lactamases among which, 22 (44%) harbored class 1, 3 (6%) carried class 2 and none contained class 3 integons. Integron carriage was significantly associated with higher rates of multiple antibiotic resistance in extended-spectrum β-lactamase producing clinical isolates of K. pneumoniae. Integron harboring isolates were more resistant to aztreonam (51.3%), ceftazidime (42.6%), cefotaxime (43.3%), cefepime (24.6%), kanamycin (43.2%), tobramycin (30.7%), norfloxcacin (32%) and spectinomycin (25.6%) compared to the organisms without integrons. On the other hand, resistance to nitrofurantoin and streptomycin was significantly higher among the integron negative isolates. PCR amplification of class1 integron variable regions revealed 9 different sized DNA fragments and isolates with similar profiles for class 1 integron variable regions showed the same antibiotic resistance phenotypes. PMID:24516451

  6. Extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in diabetic foot infections

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    Varaiya Ami

    2008-07-01

    Full Text Available Aims: Diabetic foot lesions are a major medical, social, and economic problem and are the leading cause of hospitalization for patients with diabetes, worldwide. ESBL-producing bacteria may not be detectable by routine disc diffusion susceptibility test, leading to inappropriate use of antibiotics and treatment failure. There is not much information on ESBL-producing organisms causing diabetic foot infection. An attempt was therefore made to study the ESBL-producing Escherichia coli and Klebsiella pneumoniae in diabetic foot patients with type 2 diabetes mellitus. Materials and Methods: A total of 134 isolates of E. coli and K. pneumoniae were obtained from tissue, pus swab, and wound swab samples from diabetic foot ulcers submitted for routine microbiological analysis during the period January to December 2005 from patients with diabetic foot infections who had type 2 diabetes mellitus, attending S. L. Raheja Hospital. The above isolates were tested for antimicrobial susceptibility by disc diffusion technique according to clinical and laboratory standards institute (CLSI guidelines. The screening for ESBL production was done by phenotypic confirmatory test using ceftazidime disc in the presence and absence of clavulanic acid as recommended by CLSI. Results: Among the 134 isolates, 54 (40.29% were E. coli and 80 (59.70% were K. pneumoniae; among which, ESBL production was detected in 31 (23.13% isolates. Of these 31, 15 (48.38% were E. coli and 16 (51.61% were K. pneumoniae. All the ESBL-producing isolates were found to be 100% sensitive to carbapenem (imipenem and meropenem. Mortality was found to be 3.22%, the cause of death being septicemia leading to multiple organ failure. Conclusions: The prevalence of ESBLs among members of Enterobacteriaceae constitutes a serious threat to the current beta-lactam therapy, leading to treatment failure and consequent escalation of costs. There is an urgent need to emphasize rational use of drugs to

  7. Impact of Extended Spectrum Beta-Lactamase Producing Klebsiella pneumoniae Infections in Severely Burned Patients

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    2010-09-01

    to amplify blaKPC gene products ( KPC types 1 to 4), which were then com- pared with published sequences in the NCBI BLAST pro- gram database.12,13 The...0.01) were associated with time to death. No specific clonality of the strains tested or ESBL production resistance genes were associated with...ESBL)-producing genes , which are associated with multidrug resistance. These multi- drug resistant isolates are increasingly common in the setting of

  8. Prevalence of Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae Isolates in Nosocomial and Community-Acquired Urinary Tract Infections

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    Latifpour, Mohammad; Gholipour, Abolfazl; Damavandi, Mohammad Sadegh

    2016-01-01

    Background Klebsiella pneumoniae is a family member of Enterobacteriaceae. Isolates of K. pneumoniae produce enzymes that cause decomposition of third generation cephalosporins. These enzymes are known as extended-spectrum beta-lactamase (ESBL). Resistance of K. pneumoniae to beta-lactamase antibiotics is commonly mediated by beta-lactamase genes. Objectives The aim of this study was to identify the ESBL produced by K. pneumoniae isolates that cause community-acquired and nosocomial urinary tract infections within a one-year period (2013 to 2014) in Kashani and Hajar university hospitals of Shahrekord, Iran. Patients and Methods From 2013 to 2014, 150 strains of K. pneumoniae isolate from two different populations with nosocomial and community-acquired infections were collected. The strains were then investigated by double disk synergism and multiplex polymerase chain reaction (PCR). Results The study population of 150 patients with nosocomial and community-acquired infections were divided to two groups of 75 each. We found that 48 of the K. pneumoniae isolates in the patients with nosocomial infection and 39 isolates in those with community-acquired infections produced ESBL. The prevalence of TEM1, SHV1 and VEB1 in ESBL-producing isolates in nosocomial patients was 24%, 29.3% and 10.6%, and in community-acquired patients, 17.3%, 22.7% and 8%, respectively. Conclusions The prevalence of ESBL-producing K. pneumoniae isolate is of great concern; therefore, continuous investigation seems essential to monitor ESBL-producing bacteria in patients with nosocomial and community-acquired infections. PMID:27226874

  9. Antibiotic Resistance Pattern of Extended-Spectrum Beta-Lactamases-Producing Klebsiella pneumoniae Clinical Isolates from Zahedan, Southeast Iran

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    Shahram Shahraki-Zahedani

    2016-10-01

    Full Text Available Background Resistance to various classes of antibiotics is common among extended-spectrum beta-lactamases (ESBLs-producing bacteria. Objectives To determine the antibiotic resistance pattern of ESBLs-producing K. pneumoniae clinical isolates from Zahedan. Methods In this sectional-descriptive study, susceptibility of 51 ESBLs-producing K. pneumoniae isolates to 18 antimicrobial agents was determined. Results All isolates were resistant to cefotaxime, cefpodoxime and amoxicillin as well as susceptible to colistin sulfate. Also, most isolates were resistant to trimethoprim/sulfamethoxazole and aztreonam. Conclusions Our findings demonstrated that the rate of resistance to beta-lactams, sulfonamides, tetracyclines, aminoglycosides and fluoroquinolones in ESBLs-producing K. pneumoniae isolates is high in Zahedan.

  10. Extended-spectrum beta-lactamase-producing Klebsiella spp. in a neonatal intensive care unit: risk factors for the infection and the dynamics of the molecular epidemiology.

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    Kristóf, K; Szabó, D; Marsh, J W; Cser, V; Janik, L; Rozgonyi, F; Nobilis, A; Nagy, K; Paterson, D L

    2007-08-01

    The extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp. cause worldwide problems in intensive care units. The aim of this study was to investigate the molecular epidemiology of ESBL-producing Klebsiella pneumoniae and K. oxytoca strains in a neonatal intensive care unit (NICU) in Budapest, Hungary and to determine the risk factors of the infections and the epidemiological features. Infections with Klebsiella spp. were analyzed retrospectively by reviewing the medical records between January 2001 and December 2005. Antibiotic susceptibility tests, isoelectric focusing, pulsed field gel electrophoresis, plasmid analysis, PCR for bla(TEM) and bla(SHV) and DNA sequencing analysis were performed on ESBL-producing Klebsiella isolates. A total of 45 babies were found to be infected with non-ESBL-producing Klebsiella spp. and 39 with ESBL-producing Klebsiella spp. Of the parameters analyzed, including sex, gestational age, twin pregnancy, birth weight, presence of central vascular catheter, mechanical ventilator use, parenteral nutrition, polymicrobial infection, caesarean section, transfusion and mortality, we found no statistically significant difference between the ESBL and the non-ESBL groups, or between the K. pneumoniae and K. oxytoca species. Further characterization of the ESBL-producing K. pneumoniae and K. oxytoca strains isolated between February 2001 and January 2003 revealed three distinct PFGE patterns of SHV-5-producing K. pneumoniae (A, B, E) and two distinct patterns of SHV-12-producing K. oxytoca (C,D) isolates; these had different plasmid profiles. From July to November 2005, a new SHV-5 producing K. oxytoca (F) was isolated. The molecular epidemiology of ESBL-producing organisms in a NICU over time shows substantial shifts in predominant strains. The ESBL production of the infected organisms has an impact on the survival of newborn babies with infections caused by Klebsiella spp.

  11. The role of horizontal gene transfer in the dissemination of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates in an endemic setting

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    Doi, Yohei; Adams-Haduch, Jennifer M.; Peleg, Anton Y.; D’Agata, Erika MC

    2012-01-01

    The contribution of horizontal gene transmission (HGT) in the emergence and spread of extended-spectrum beta-lactamase (ESBL)-producing gram-negative bacteria during periods of endemicity is unclear. Over a 12-month period, rectal colonization with SHV-5 and SHV-12 producing-Escherichia coli and Klebsiella pneumoniae was quantified among a cohort of residents in a long-term care facility. Demographic and clinical data were collected on colonized residents. Transferability of SHV-encoding plasmids and pulsed-field gel electrophoresis was performed to quantify the contribution of HGT and cross-transmission, respectively. A total of 25 (12%) of 214 enrolled patients were colonized with 11 SHV-5- and 17 SVH-12-producing E. coli and K. pneumoniae. Clonally-related isolates were detected among multiple residents residing on the same and different wards. Among 12 clonally-distinct isolates, HGT of SHV-5- and SHV-12-encoding plasmids was identified among 6 (50%) isolates. HGT among clonally-distinct strains contributes to the transmission dynamics of these ESBL-producing gram-negative bacteria and should be considered when evaluating the spread of these pathogens. PMID:22722012

  12. Risk factors for extended-spectrum beta-lactamase-producing Serratia marcescens and Klebsiella pneumoniae acquisition in a neonatal intensive care unit.

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    Crivaro, V; Bagattini, M; Salza, M F; Raimondi, F; Rossano, F; Triassi, M; Zarrilli, R

    2007-10-01

    We investigated the molecular epidemiology of gentamicin-resistant, extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Serratia marcescens, and risk factors associated with their acquisition in a neonatal intensive care unit (NICU) of a university hospital in Italy. During the study period (April-November 2004), S. marcescens was responsible for six infections and 31 colonisations, while K. pneumoniae was responsible for six infections and 103 colonisations. Concurrent isolation of both organisms occurred in 24 neonates. Molecular typing identified one major pulsed-field gel electrophoresis pattern each for S. marcescens and K. pneumoniae strains isolated during the study period. An 80 kb plasmid containing bla(SHV-12), bla(TEM-1) and aac(6')-Ib genes, isolated from both S. marcescens and K. pneumoniae strains, and showing identical restriction profiles, transferred resistance to third-generation cephalosporins to a previously susceptible Escherichia coli host. Birthweight, gestational age and use of invasive devices were significantly associated with S. marcescens and K. pneumoniae acquisition on univariate analysis, while empiric antimicrobial treatment with ampicillin and gentamicin, and duration of hospital stay, proved to be the only independent risk factors. In conclusion, conjugal plasmid transfer and empiric antimicrobial therapy with ampicillin and gentamicin might have contributed to the selection and spread of gentamicin-resistant ESBL-producing Enterobacteriaceae in the NICU.

  13. Validation of Minim typing for fast and accurate discrimination of extended-spectrum, beta-lactamase-producing Klebsiella pneumoniae isolates in tertiary care hospital.

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    Brhelova, Eva; Kocmanova, Iva; Racil, Zdenek; Hanslianova, Marketa; Antonova, Mariya; Mayer, Jiri; Lengerova, Martina

    2016-09-01

    Minim typing is derived from the multi-locus sequence typing (MLST). It targets the same genes, but sequencing is replaced by high resolution melt analysis. Typing can be performed by analysing six loci (6MelT), four loci (4MelT) or using data from four loci plus sequencing the tonB gene (HybridMelT). The aim of this study was to evaluate Minim typing to discriminate extended-spectrum beta-lactamase producing Klebsiella pneumoniae (ESBL-KLPN) isolates at our hospital. In total, 380 isolates were analyzed. The obtained alleles were assigned according to both the 6MelT and 4MelT typing scheme. In 97 isolates, the tonB gene was sequenced to enable HybridMelT typing. We found that the presented method is suitable to quickly monitor isolates of ESBL-KLPN; results are obtained in less than 2 hours and at a lower cost than MLST. We identified a local ESBL-KLPN outbreak and a comparison of colonizing and invasive isolates revealed a long term colonization of patients with the same strain.

  14. [Spreading and mechanisms of antibiotic resistance of microorganisms, producing beta-lactamases. Molecular mechanisms of resistance to beta-lactams of Klebsiella spp. strains, isolated in cases of nosocomial infections].

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    Ivanov, D V; Egorov, A M

    2008-01-01

    Antibiotic sensivity of nosocomial Klebsiella spp. strains (n = 212), isolated from patients treated in 30 medical centers of 15 various regions of Russia was investigated. The Klebsiella genus was represented by the following species: Klebsiella pneumoniae ss. pneumoniae--182 (85.8%), Klebsiella pneumoniae ss. ozaenae--1 (0.5%), Klebsiella oxytoca--29 (13.7%) isolates. The most active antibacterial agents against the investigated strains were carbapenems (imipenem and meropenem). Among 3rd generation cephalosporine the lowest MICs were observed for ceftazidime/clavulanic acid (MIC50--0.25 microg/ml, MIC90--64 microg/ml) and cefoperazone/sulbactam (MIC50--16 microg/ml, MIC90--64 microg/ml). Beta-lactamase genes (TEM, SHV, CTX) were detected in 42 Klebsiella pneumoniae ss. pneumoniae strains by PCR. Alone or in various combinations TEM type beta-lactamases have been found in 16 (38.1%) isolates, SHV--in 29 (69%), and CTX--in 27 (64.3%). Combinations of 2 different determinants were detected in 23.8% of the isolates, 3--in 26.2%. There were not isolates producing MBL class B among resistant to carbapenems nosocomial Klebsiella spp. strains.

  15. Occurrence of efflux mechanism and cephalosporinase variant in a population of Enterobacter aerogenes and Klebsiella pneumoniae isolates producing extended-spectrum beta-lactamases.

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    Tran, Que-Tien; Dupont, Myrielle; Lavigne, Jean-Philippe; Chevalier, Jacqueline; Pagès, Jean-Marie; Sotto, Albert; Davin-Regli, Anne

    2009-04-01

    We investigated the occurrence of multidrug resistance in 44 Enterobacter aerogenes and Klebsiella pneumoniae clinical isolates. Efflux was involved in resistance in E. aerogenes isolates more frequently than in K. pneumoniae isolates (100 versus 38% of isolates) and was associated with the expression of phenylalanine arginine beta-naphthylamide-susceptible active efflux. AcrA-TolC overproduction in E. aerogenes isolates was noted. An analysis of four E. aerogenes isolates for which cefepime MICs were high revealed no modification in porin expression but a new specific mutation in the AmpC beta-lactamase.

  16. A trial with IgY chicken antibodies to eradicate faecal carriage of Klebsiella pneumoniae and Escherichia coli producing extended-spectrum beta-lactamases

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    Anna-Karin Jonsson

    2015-11-01

    Full Text Available Background: Extended-spectrum beta-lactamase (ESBL-producing Enterobacteriaceae is an emerging therapeutic challenge, especially in the treatment of urinary tract infections. Following an outbreak of CTX-M-15 Klebsiella pneumoniae in Uppsala, Sweden, an orphan drug trial on IgY chicken antibodies was undertaken in an attempt to eradicate faecal carriage of ESBL-producing K. pneumoniae and Escherichia coli. Methods: Hens were immunised with epitopes from freeze-dried, whole-cell bacteria (ESBL-producing K. pneumoniae and E. coli and recombinant proteins of two K. pneumoniae fimbriae subunits (fimH and mrkD. The egg yolks were processed according to good manufacturing practice and the product was stored at−20°C until used. Using an internal database from the outbreak and the regular laboratory database, faecal carriers were identified and recruited from May 2005 to December 2013. The participants were randomised in a placebo-controlled 1:1 manner. Results: From 749 eligible patients, 327 (44% had deceased, and only 91 (12% were recruited and signed the informed consent. In the initial screening performed using the polymerase chain reaction, 24 participants were ESBL positive and subsequently randomised and treated with either the study drug or a placebo. The study was powered for 124 participants. Because of a very high dropout rate, the study was prematurely terminated. From the outbreak cohort (n=247, only eight patients were screened, and only one was positive with the outbreak strain in faeces. Conclusions: The present study design, using IgY chicken antibodies for the eradication of ESBL-producing K. pneumonia and E. coli, was ineffective in reaching its goal due to high mortality and other factors resulting in a low inclusion rate. Spontaneous eradication of ESBL-producing bacteria was frequently observed in recruited participants, which is consistent with previous reports.

  17. Nosocomial extended-spectrum beta-lactamase-producing Klebsiella pneumoniae bacteremia in hemodialysis patients and the implications for antibiotic therapy

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    Chih-Chao Yang

    2014-11-01

    Conclusions: In accordance with our previous study, our results have demonstrated the inferiority of flomoxef to carbapenems in the treatment of HD access-related ESBL-Kp bacteremia and provide an insight into the possibility of using ertapenem rather than flomoxef as an initial or de-escalating therapy for infections caused by ESBL-producing bacteria.

  18. [Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyo University Hospital--the second report].

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    Kawakami, S; Ono, Y; Yamamoto, M; Matumura, M; Okamoto, R; Inoue, M; Miyazawa, Y

    2000-01-01

    We studied the high-level resistant to cefotaxime (CTX, MIC > or = 512 micrograms/ml) clinical isolates of Escherichia coli and Klebsiella pneumoniae in Teikyo University Hospital. The CTX-resistance could be transferred to E. coli K-12 chi 1037 or ML4903 strains from 30 of the 33 isolates by conjugation at a frequency of 10(-4). When the hydrolysis rate of benzylpenicillin was 100%, the beta-lactamases which were extracted from the transconjugants hydrolyzed CTX, CAZ and AZT at the rate of 38-95%, 0-8.6% and 0-56%, respectively. These results demonstrate that these enzymes should be categorized into ESBL. The nucleotide sequence of CTX-resistant gene was identified to that of the CTX-M2 gene which was first described in Argentina. It was found to have 99.9% homology to Toho-1 gene in Japan and 99.6% homology to CMY-2 gene. Using a PCR methods for the detection of one of ESBL gene such as CTX-M2, Toho-1 or CMY-2, the DNA was amplified from all strains (11 isolates of E. coli and 21 isolates of K. pneumoniae).

  19. The therapeutic effect of tigecycline, unlike that of Ceftazidime, is not influenced by whether the Klebsiella pneumoniae strain produces extended-spectrum beta-lactamases in experimental pneumonia in rats

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    Goessens, W.H.F.; Mouton, J.W.; Kate, M.T. Ten; Sorgel, F.; Kinzig, M.; Bakker-Woudenberg, I.A.

    2013-01-01

    The efficacies of tigecycline and ceftazidime against fatal pneumonia in rats caused by an extended-spectrum beta-lactamase (ESBL)-positive Klebsiella pneumoniae strain or its wild-type (WT) progenitor were compared. Ceftazidime at 12.5 or 50 mg/kg of body weight twice daily (b.i.d.) was effective (

  20. Caracterización de Klebsiella pneumoniae productora de la beta-lactamasa SHV-5, en una unidad de cuidados intensivos Characterization of SHV-5 beta-lactamase-producing Klebsiella pneumoniae in an intensive care unit

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    Verónica Andrade

    2004-12-01

    chain reaction (RAPD-PCR and serotyping, beta-Lactamase isoelectric focusing (IEF, and nucleotide sequencing of PCR products. RESULTS: Serotype 61 was predominant and correlated with genomic fingerprints of RAPD and PFGE in 11 of 15 isolates. One SHV-5-producer predominant clone with a high case-fatality rate was identified. CONCLUSIONS: Molecular biology techniques are useful tools to characterize the K. pneumoniae clone isolated from patients and health care workers, suggesting potential cross-transmission. These data call for strengthening control programs to prevent dissemination of nosocomial infections in the studied hospital.

  1. [Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyou University Hospital--the first report].

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    Kawakami, S; Ono, Y; Yamamoto, M; Matumura, M; Okamoto, R; Inoue, M; Miyazawa, Y

    1999-11-01

    We studied the cefotaxime (CTX)-resistant (MIC > or = 32 micrograms/ml) clinical isolates of E. coli and K. pneumoniae in Teikyo University Hospital from 1990 to 1996. The incidence of CTX-resistant isolates was 0.4% (6/1,282) in E. coli and 0.6% (7/1,044) in K. pneumoniae, in 1990. In 1995, the incidence of CTX-resistance increased to 1.7% (50/2,910) in E. coli (p = 0.0013) and 7.2% (144/1,996) in K. pneumoniae (p coli, 22 isolates of K. pneumoniae), which were detected in 1996-1997, was > 512 micrograms/ml, 8 micrograms/ml, > 512 micrograms/ml, 8 micrograms/ml, 4 micrograms/ml, > 512 micrograms/ml, 16 micrograms/ml, > 512 micrograms/ml, 256 micrograms/ml, 32 micrograms/ml, 2 micrograms/ml, 0.25 microgram/ml and 0.25 microgram/ml, respectively. This susceptibility pattern were very similar to the Toho-1 type beta-lactamases producing strains.

  2. Ertapenem susceptibility of extended spectrum beta-lactamase-producing organisms

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    Selby Edward B

    2007-06-01

    Full Text Available Abstract Background Infections caused by multiply drug resistant organisms such as extended spectrum beta-lactamase (ESBL-producing Escherichia coli and Klebsiella pneumoniae are increasing. Carbapenems (imipenem and meropenem are the antibiotics commonly used to treat these agents. There is limited clinical data regarding the efficacy of the newest carbapenem, ertapenem, against these organisms. Ertapenem susceptibility of ESBL-producing E. coli and K. pneumoniae clinical isolates were evaluated and compared to imipenem to determine if imipenem susceptibility could be used as a surrogate for ertapenem susceptibility. Methods 100 ESBL isolates (n = 34 E. coli and n = 66 K. pneumoniae collected from 2005–2006 clinical specimens at WRAMC were identified and tested for susceptibility by Vitek Legacy [bioMerieux, Durham, NC]. Ertapenem susceptibility was performed via epsilometer test (E-test [AB Biodisk, Solna, Sweden]. Results 100% of ESBL isolates tested were susceptible to ertapenem. 100% of the same isolates were also susceptible to imipenem. Conclusion These results, based on 100% susceptibility, suggest that ertapenem may be an alternative to other carbapenems for the treatment of infections caused by ESBL-producing E. coli and K. pneumoniae. Clinical outcomes studies are needed to determine if ertapenem is effective for the treatment of infection caused by these organisms. However, due to lack of resistant isolates, we are unable to conclude whether imipenem susceptibility accurately predicts ertapenem susceptibility.

  3. Occurrence and characteristics of extended spectrum beta-lactamases-producing Enterobacteriaceae from foods of animal origin.

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    Tekiner, İsmail Hakkı; Özpınar, Haydar

    2016-01-01

    Presence of extended spectrum beta-lactamases (ESBL) in bacteria is a growing health concern of global significance. The local, regional, national, and international epidemiological studies for extended spectrum beta-lactamases-producing Enterobacteriaceae and their encoding genes in foods are still incomplete. The objective of this study was to determine the occurrence of extended spectrum beta-lactamases-producing Enterobacteriaceae and the characteristics of their encoding genes from a total of 250 samples of various foods of animal-origin (100 raw chicken meat, 100 raw cow milk, and 50 raw cow milk cheese) sold in Turkey. Overall, 55 isolates were positive as extended spectrum beta-lactamases-producing Enterobacteriaceae. The most prevalent extended spectrum beta-lactamases-producing strain were identified as Escherichia coli (80%), followed by Enterobacter cloacae (9.1%), Citrobacter braakii (5.5%), Klebsiella pneumoniae (3.6%), and Citrobacter werkmanii (1.8%) by Vitek(®) MS. The simultaneous production of extended spectrum beta-lactamases and AmpC was detected in five isolates (9.1%) in E. coli (80%) and E. cloacae (20%). The frequency rates of blaTEM, blaCTX-M, and blaSHV were 96.4%, 53.7%, and 34.5%, respectively. The co-existence of bla-genes was observed in 82% of extended spectrum beta-lactamases producers with a distribution of blaTEM &blaCTX-M (52.7%), blaTEM &blaSHV (20%), blaTEM &blaCTX-M &blaSHV (12.7%), and blaSHV &blaCTX-M (1.8%). The most prevalent variant of blaCTX-M clusters was defined as blaCTX-M-1 (97.2%), followed by blaCTX-M-8 (2.8%). In summary, the analysed foods were found to be posing a health risk for Turkish consumers due to contamination by Enterobacteriaceae with a diversity of extended spectrum beta-lactamases encoding genes.

  4. Occurrence and characteristics of extended spectrum beta-lactamases-producing Enterobacteriaceae from foods of animal origin

    Directory of Open Access Journals (Sweden)

    İsmail Hakkı Tekiner

    2016-06-01

    Full Text Available Abstract Presence of extended spectrum beta-lactamases (ESBL in bacteria is a growing health concern of global significance. The local, regional, national, and international epidemiological studies for extended spectrum beta-lactamases-producing Enterobacteriaceae and their encoding genes in foods are still incomplete. The objective of this study was to determine the occurrence of extended spectrum beta-lactamases-producing Enterobacteriaceae and the characteristics of their encoding genes from a total of 250 samples of various foods of animal-origin (100 raw chicken meat, 100 raw cow milk, and 50 raw cow milk cheese sold in Turkey. Overall, 55 isolates were positive as extended spectrum beta-lactamases-producing Enterobacteriaceae. The most prevalent extended spectrum beta-lactamases-producing strain were identified as Escherichia coli (80%, followed by Enterobacter cloacae (9.1%, Citrobacter braakii (5.5%, Klebsiella pneumoniae (3.6%, and Citrobacter werkmanii (1.8% by Vitek® MS. The simultaneous production of extended spectrum beta-lactamases and AmpC was detected in five isolates (9.1% in E. coli (80% and E. cloacae (20%. The frequency rates of blaTEM, blaCTX-M, and blaSHV were 96.4%, 53.7%, and 34.5%, respectively. The co-existence of bla -genes was observed in 82% of extended spectrum beta-lactamases producers with a distribution of blaTEM & blaCTX-M (52.7%, blaTEM & blaSHV (20%, blaTEM & blaCTX-M & blaSHV (12.7%, and blaSHV & blaCTX-M (1.8%. The most prevalent variant of blaCTX-M clusters was defined as blaCTX-M-1 (97.2%, followed by blaCTX-M-8 (2.8%. In summary, the analysed foods were found to be posing a health risk for Turkish consumers due to contamination by Enterobacteriaceae with a diversity of extended spectrum beta-lactamases encoding genes.

  5. Detection of Amp C genes encoding for beta-lactamases in Escherichia coli and Klebsiella pneumoniae

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    M Shanthi

    2012-01-01

    Full Text Available Purpose : Amp C beta-lactamase are Ambler class C enzymes that confer resistance to extended spectrum cephalosporins and are not inhibited by beta-lactamase inhibitors. Their detection is crucial, since the phenotypic tests are not standardised leading to ambiguity in interpretation of results. This study was done to detect the types of Amp C prevalent in Escherichia coli and Klebsiella pneumoniae by multiplex polymerase chain reaction (PCR. Materials and Methods : Seventy-seven consecutive cefoxitin resistant clinical isolates of E. coli (n = 25 and K. pneumoniae (n = 52 were included in the study. Antibiotic susceptibility testing to various classes of antibiotics was performed by disc diffusion using Clinical Laboratory Standards Institute (CLSI guidelines. Minimum inhibitory concentration (MIC to cefoxitin, imipenem and meropenem were determined by broth microdilution method. Isolates were screened for production of Extended Spectrum Beta-Lactamase (ESBL. Multiplex PCR was performed for the detection of Amp C genes after phenotypic testing (Hodge test and inhibitor based test. Results : Cefoxitin Hodge test was positive in 40 isolates which included 20 E. coli and 20 K. pneumoniae. There was zone enhancement with boronic acid in 55 isolates, of which 36 were K. pneumoniae and 19 were E. coli. Multiplex PCR detected Amp C in 11/25 E. coli and 12/52 K. pneumoniae isolates. The Amp C genes detected were CIT (Amp C origin - Citrobacter freundii, DHA (Dhahran Hospital, Saudi Arabia, ACC (Ambler class C, EBC (Amp C origin - Enterobacter cloacae groups. ESBL was co-produced in 54 isolates. Conclusions : Amp C was detected in 29.87% of the study isolates. Majority of them co-produced ESBL. The most common Amp C was the CIT family. Screen tests for cefoxitin resistance may be falsely positive due to production of carbapenamases.

  6. Use of whole-genome sequencing to trace, control and characterize the regional expansion of extended-spectrum beta-lactamase producing ST15 Klebsiella pneumoniae

    NARCIS (Netherlands)

    Zhou, Kai; Lokate, Mariette; Deurenberg, Ruud H.; Tepper, Marga; Arends, Jan P.; Raangs, Erwin G.C.; Lo-Ten-Foe, Jerome; Grundmann, Hajo; Rossen, John W. A.; Friedrich, Alexander W.

    2016-01-01

    The study describes the transmission of a CTX-M-15-producing ST15 Klebsiella pneumoniae between patients treated in a single center and the subsequent inter-institutional spread by patient referral occurring between May 2012 and September 2013. A suspected epidemiological link between clinical K. pn

  7. Extended-spectrum-beta-lactamase-producing Enterobacteriaceae in Yaounde, Cameroon

    OpenAIRE

    Gangoue Pieboji, Joseph; Bedenic, B.; Koulla-Shiro, S.; Randegger, C.; Adiogo, D.; Ngassam, P.; Ndumbe, P; Hachler, H.

    2005-01-01

    Organisms producing extended-spectrum beta-lactamases (ESBLs) have been reported in many countries, but there is no information on the prevalence of ESBL-producing members of the family Enterobacteriaceae in Cameroon. A total of 259 Enterobacteriaceae strains were isolated between 1995 and 1998 from patients at the Yaounde Central Hospital in Cameroon. Enterobacterial isolates resistant to extended-spectrum cephalosporin and monobactam were screened for ESBL production by the double-disk (DD)...

  8. Novel plasmid-encoded class C beta-lactamase (MOX-2) in Klebsiella pneumoniae from Greece.

    Science.gov (United States)

    Raskine, Laurent; Borrel, Isabelle; Barnaud, Guilène; Boyer, Sophie; Hanau-Berçot, Béatrice; Gravisse, Jérome; Labia, Roger; Arlet, Guillaume; Sanson-Le-Pors, Marie-José

    2002-07-01

    Klebsiella pneumoniae KOL, a clinical strain resistant to various beta-lactams, was isolated from the stools of a patient from Greece. This strain harbored a new pI 9.1 plasmid-mediated AmpC beta-lactamase with unusually high levels of hydrolytic activity for cefoxitin and cefotetan that we named MOX-2. Sequencing of bla(MOX-2) revealed 93.2, 92.9, 92.7, and 73.1% identities with the deduced amino acid sequences of CMY-8, MOX-1, CMY-1, and the AmpC beta-lactamase of Aeromonas sobria, respectively.

  9. Impact of empirical treatment in extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. bacteremia. A multicentric cohort study

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    Peralta Galo

    2012-10-01

    Full Text Available Abstract Background The objective of this study is to analyze the factors that are associated with the adequacy of empirical antibiotic therapy and its impact in mortality in a large cohort of patients with extended-spectrum β-lactamase (ESBL - producing Escherichia coli and Klebsiella spp. bacteremia. Methods Cases of ESBL producing Enterobacteriaceae (ESBL-E bacteremia collected from 2003 through 2008 in 19 hospitals in Spain. Statistical analysis was performed using multivariate logistic regression. Results We analyzed 387 cases ESBL-E bloodstream infections. The main sources of bacteremia were urinary tract (55.3%, biliary tract (12.7%, intra-abdominal (8.8% and unknown origin (9.6%. Among all the 387 episodes, E. coli was isolated from blood cultures in 343 and in 45.71% the ESBL-E was multidrug resistant. Empirical antibiotic treatment was adequate in 48.8% of the cases and the in hospital mortality was 20.9%. In a multivariate analysis adequacy was a risk factor for death [adjusted OR (95% CI: 0.39 (0.31-0.97; P = 0.04], but not in patients without severe sepsis or shock. The class of antibiotic used empirically was not associated with prognosis in adequately treated patients. Conclusion ESBL-E bacteremia has a relatively high mortality that is partly related with a low adequacy of empirical antibiotic treatment. In selected subgroups the relevance of the adequacy of empirical therapy is limited.

  10. Molecular characterization and epidemiology of extended-spectrum-beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates causing health care-associated infection in Thailand, where the CTX-M family is endemic.

    Science.gov (United States)

    Kiratisin, Pattarachai; Apisarnthanarak, Anucha; Laesripa, Chaitat; Saifon, Piyawan

    2008-08-01

    Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae have rapidly spread worldwide and pose a serious threat for health care-associated (HA) infection. We conducted molecular detection and characterization of ESBL-related bla genes, including bla(TEM), bla(SHV), bla(CTX-M), bla(VEB), bla(OXA), bla(PER), and bla(GES), among 362 isolates of ESBL-producing E. coli (n = 235) and ESBL-producing K. pneumoniae (n = 127) collected from patients who met the definition of HA infection at two major university hospitals in Thailand from December 2004 to May 2005. The prevalence of ESBL-producing E. coli and ESBL-producing K. pneumoniae, patient demographics and the susceptibilities of these bacteria to various antimicrobial agents were described. A total of 87.3% of isolates carried several bla genes. The prevalence of bla(CTX-M) was strikingly high: 99.6% for ESBL-producing E. coli (CTX-M-14, -15, -27, -40, and -55) and 99.2% for ESBL-producing K. pneumoniae (CTX-M-3, -14, -15, -27, and -55). ISEcp1 was found in the upstream region of bla(CTX-M) in most isolates. Up to 77.0% and 71.7% of ESBL-producing E. coli and ESBL-producing K. pneumoniae, respectively, carried bla(TEM); all of them encoded TEM-1. ESBL-producing K. pneumoniae carried bla(SHV) at 87.4% (SHV-1, -2a, -11, -12, -27, -71, and -75) but only at 3.8% for ESBL-producing E. coli (SHV-11 and -12). bla genes encoding VEB-1 and OXA-10 were found in both ESBL-producing E. coli (8.5% and 8.1%, respectively) and ESBL-producing K. pneumoniae (10.2% and 11.8%, respectively). None of the isolates were positive for bla(PER) and bla(GES). Pulsed-field gel electrophoresis analysis demonstrated that there was no major clonal relationship among these ESBL producers. This is the first study to report CTX-M-3, CTX-M-27, CTX-M-40, SHV-27, SHV-71, and SHV-75 in Thailand and to show that CTX-M ESBL is highly endemic in the country.

  11. PREVALENCE AND ANTIMICROBIAL RESISTANCE PATTERN OF EXTENDED SPECTRUM BETA LACTAMASE PRODUCING KLEBSIEL LA SPP

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    Sunanda

    2013-03-01

    Full Text Available ABSTRACT: INTRODUCTION AND OBJECTIVES: Extended spectrum beta lactamase (ESBL producing Klebsiella spp have emerged as an important pathogen due to their high resistance against most of the antibiotics. Their detection an d antibiotic resistance pattern is required for proper management of cases. In this study we report th e prevalence and antibiotic resistance of such Klebsiella isolates. METHODS: A total of 100 clinical isolates of Klebsiella fro m different clinical samples were tested for ESBL production by d ouble disc approximation test and CLSI phenotypic method. Antibiotic susceptibility of all th e Klebsiella isolates were performed by Kirby-Bauer disc diffusion test. RESULTS: of 100 Klebsiella isolates 53 showed ESBL production. All ESBL producers were resistant to beta lactam antibiotics. Antibiotic resistance among ESBL producing strains was high as compared to non ESBL producing strains. INTERPRETATION & CONCLUSION: In the present study a large number of Klebsiella s pp. isolated were found to be ESBL producers. Continuing monitoring of ESBL production and antimicrobial susceptibility testing is essential to avoid treatment failure.

  12. First report of a novel extended-spectrum beta-lactamase KOXY-2 producing Klebsiella oxytoca that hydrolyses cefotaxime and ceftazidime.

    Science.gov (United States)

    Younes, A; Hamouda, A; Amyes, S G B

    2011-06-01

    Klebsiella oxytoca strains MU946294N and MB193997E were isolated from patients in Scotland. Strain MU946294N was resistant to pencillins, monbactams and cephalosporins. Isolate MB193997E displayed a β-lactam resistance phenotype consistent with chromosomal β-lactamase overproduction. No bla(TEM), bla(SHV) or bla(CTX-M) genes could be amplified in either strain; however, amplification by PCR was found with primers for the bla(OXY-2) gene. This β-lactamase gene in MU946294N differed by one mutation from the all other bla(OXY) genes previously reported, with an amino acid substitution Alanine237 Threonine enhancing the binding of cefotaxime. Strain MB193997E showed mutations at positions 255 and 283, neither of which affect function. Based on rpoB and gyrA characterization, both strains were assigned to the KoII phylogenic group but they were completely dissimilar from each other by PFGE. This study is the first to report the substitution of Alanine to Threonine at position 237 in a OXY- 2 β-lactamase and this enhances resistance to cefotaxime.

  13. Genetic and biochemical characterization of the chromosomal class A beta-lactamases of Raoultella (formerly Klebsiella) planticola and Raoultella ornithinolytica.

    Science.gov (United States)

    Walckenaer, Estelle; Poirel, Laurent; Leflon-Guibout, Véronique; Nordmann, Patrice; Nicolas-Chanoine, Marie-Hélène

    2004-01-01

    Enterobacterial strains of Raoultella spp. display a penicillinase-related beta-lactam resistance pattern suggesting the presence of a chromosomal bla gene. From whole-cell DNA of Raoultella planticola strain ATCC 33531(T) and Raoultella ornithinolytica strain ATCC 31898(T), bla genes were cloned and expressed into Escherichia coli. Each gene encoded an Ambler class A beta-lactamase, named PLA-1 and ORN-1 for R. planticola and R. ornithinolytica, respectively. These beta-lactamases (291 amino acids), with the same pI value of 7.8, had a shared amino acid identity of 94%, 37 to 47% identity with the majority of the chromosome-encoded class A beta-lactamases previously described for Enterobacteriaceae, and 66 to 69% identity with the two beta-lactamases LEN-1 and SHV-1 from Klebsiella pneumoniae. However, the highest identity percentage (69 to 71%) was found with the plasmid-mediated beta-lactamase TEM-1. PLA-1, which displayed very strong hydrolytic activity against penicillins, also displayed significant hydrolytic activity against cefepime and, to a lesser extent, against cefotaxime and aztreonam, but there was no hydrolytic activity against ceftazidime. Such a substrate profile suggests that the Raoultella beta-lactamases PLA-1 and ORN-1 should be classified into the group 2be of the beta-lactamase classification of K. Bush, G. A. Jacoby, and A. A. Medeiros (Antimicrob. Agents Chemother. 39:1211-1233, 1995). The highly homologous regions upstream of the bla(PLA-1A) and bla(ORN-1A) genes comprised a nucleotide sequence identical to the -35 region and another one very close to the -10 region of the bla(LEN-1) gene. From now on, as the bla gene sequences of the most frequent Raoultella and Klebsiella species are available, the bla gene amplification method can be used to differentiate these species from each other, which the biochemical tests currently carried out in the clinical laboratory are unable to do.

  14. Extended-Spectrum-Beta-Lactamases, AmpC Beta-Lactamases and Plasmid Mediated Quinolone Resistance in Klebsiella spp. from Companion Animals in Italy

    DEFF Research Database (Denmark)

    Donati, Valentina; Feltrin, Fabiola; Hendriksen, Rene S.

    2014-01-01

    We report the genetic characterization of 15 Klebsiella pneumoniae (KP) and 4 isolates of K. oxytoca (KO) from clinical cases in dogs and cats and showing extended-spectrum cephalosporin (ESC) resistance. Extended spectrum beta-lactamase (ESBL) and AmpC genes, plasmid-mediated quinolone resistance...... patterns observed, including two clusters of two (ST340) and four (ST101) indistinguishable isolates, respectively. All isolates harbored at least one ESBL or AmpC gene, all carried on transferable plasmids (IncR, IncFII, IncI1, IncN), and 16/19 were positive for PMQR genes (qnr family or aac(6')-Ib...... of multidrug-resistant Klebsiella with ESBL, AmpC and PMQR determinants, poses further and serious challenges in companion animal therapy and raise concerns for possible bidirectional transmission between pets and humans, especially at household level....

  15. Approaches to characterize extended spectrum beta-lactamase/beta-lactamase producing Escherichia coli in healthy organized vis-a-vis backyard farmed pigs in India.

    Science.gov (United States)

    Samanta, Indranil; Joardar, Siddhartha N; Mahanti, Achintya; Bandyopadhyay, Samiran; Sar, Tapas K; Dutta, Tapan K

    2015-12-01

    The study was undertaken to investigate the occurrence and to characterize the ESBL/beta-lactamase producing-Escherichia coli in healthy pigs of organized and backyard farms in West Bengal, India. Total 200 rectal swabs were collected randomly from healthy pigs maintained in four organized farms and 10 backyard farms (n=100 each) and 76 isolates were identified as E. coli from organized (48/100, 48%) and backyard pigs (28/100, 28%). Twelve E. coli isolates (6%) in the present study were detected to possess any of the ESBL/beta-lactamase genes studied. ESBL/beta-lactamase producers were isolated with significantly more frequency from backyard pigs than the organized farm pigs (p=0.026). Six of ESBL/beta-lactamase producing isolates were phenotypically confirmed as CTX-M producers and ten of them were confirmed as TEM/SHV producers. PCR and sequencing of the amplified product from representative isolates revealed the presence of blaCTX-M-9, blaSHV-12 and blaTEM-1. No unique combination of the studied beta lactamase genes for organized and backyard farm pig isolates was noted. The ESBL isolates belonged to O13, O55, O133, O153, O157, O158, O166, rough and OUT serogroups. The association of heat labile toxin (elt) (pIndia.

  16. Dissemination of extended-spectrum beta-lactamase producing enterobacteriaceae in children

    OpenAIRE

    Lima, S.B.; Ferreira, H.N.

    2013-01-01

    As Enterobacteriaceae produtoras de beta-lactamases de espectro alargado (extended-spectrum beta-lactamase producing Enterobacteriaceae - EESBL) têm sido consideradas importantes agentes patogénicos hospitalares. Nos últimos tempos, a sua disseminação na comunidade, é uma realidade que pode condicionar a terapêutica empírica. A colonização fecal de pessoas saudáveis com EESBL é uma realidade que pode comprometer o controlo de infeção nos cuidados de saúde hospitalares e na prestação ...

  17. Extensive Dissemination of Extended Spectrum beta-Lactamase-Producing Enterobacteriaceae in a Dutch Nursing Home

    NARCIS (Netherlands)

    Willemsen, I.; Nelson, J.; Hendriks, Y.; Mulders, A.; Verhoeff, S.; Mulder, P.; Roosendaal, R.; Zwaluw, K. van der; Verhulst, C.; Kluytmans-Vandenbergh, M.F.; Kluytmans, J.

    2015-01-01

    OBJECTIVE Risk factors for rectal carriage of ESBL-E and transmission were investigated in an outbreak of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E). DESIGN Rectal carriage of ESBL-E was determined in a cross-sectional survey by culture of perianal swabs or fecal samples.

  18. Non-Beta-Lactamase-Producing Penicillin-Resistant Enterococcus faecium in a Clinical Setting

    Directory of Open Access Journals (Sweden)

    Daniel Eymard

    1990-01-01

    Full Text Available Six clinical isolates of Enterococcus faecium highly resistant to penicillin are reported. These strains did not produce beta-lactamase and no plasmid DNA could be detected. It is postulated that the mechanism of resistance is one or more chromosomally mediated alterations of penicillin-binding proteins.

  19. Multidrug resistance found in extended-spectrum beta-lactamase-producing Enterobacteriaceae from rural water reservoirs in Guantao, China

    Directory of Open Access Journals (Sweden)

    Hongna eZhang

    2015-03-01

    Full Text Available Extended-spectrum beta-lactamase (ESBL-producing Enterobacteriaceae have been isolated from humans and animals across the world. However, data on prevalence of ESBL-producing Enterobacteriaceae from rural water reservoirs is limited. This study aimed to isolate and characterize ESBL-producing Enterobacteriaceae in rural water reservoirs in Guantao, China. ESBL-producing Enterobacteriaceae were found in 5 (16.7% of 30 sampled rural water reservoirs. 66 individual isolates expressing an ESBL phenotype were obtained in the present study. Species identification showed that 42 representatives of Escherichia coli, 17 Klebsiella pneumoniae, 4 Raoultella planticola, and 3 Enterobacter cloacae. 20 isolates contained a single bla gene, including CTX-M (17 strains, TEM (2 strains, and SHV (1 strain. 46 isolates contained more than one type of beta-lactamase genes. ESBL-producing Enterobacteriaceae isolated in this study were all multidrug resistant. These findings indicated that the seroius contamination of ESBL-producing Enterobacteriaceae in rural water resevoirs existed in Guantao, China.

  20. Mortalidad por bacteriemia causada por Escherichia coli y Klebsiella spp. productoras de beta lactamasas de espectro extendido: cohorte retrospectiva en un hospital de Lima, Perú Mortality caused by bacteremia Escherichia coli and Klebsiella spp. extended-spectrum beta-lactamase- producers: a retrospective cohort from a hospital in Lima, Peru

    Directory of Open Access Journals (Sweden)

    Diego Adrianzén

    2013-03-01

    Full Text Available Objetivos. Evaluar los factores asociados a la mortalidad causada por bacteriemias por Escherichia coli y Klebsiella spp. productoras de beta lactamasas de espectro extendido (BLEE. Materiales y Métodos. Se realizó un estudio de cohortes retrospectivo, que incluyó 85 pacientes mayores de 16 años con diagnóstico de bacteriemia por Escherichia coli o Klebsiella spp. hospitalizados entre 2006 y 2008 en el Hospital Nacional Cayetano Heredia. Las cohortes se clasificaron de acuerdo a la producción de BLEE según los resultados de los hemocultivos. Se evaluaron los factores asociados a la mortalidad cruda y atribuible empleando regresión de Poisson en un modelo multivariado, con lo que se obtuvo riesgos relativos ajustados (RRa. Además, se construyeron curvas de mortalidad. Resultados. Se encontró que el 35,3% de las bacteriemias fueron debidas a cepas productoras de BLEE. El análisis de la mortalidad cruda mostró una mayor mortalidad en el grupo de cepas productoras de BLEE (63,3%. El RRa fue de 1,5 (IC95%: 1,02-2,3. En el caso de mortalidad atribuible, la proporción también fue mayor (63,3%, el RRa fue de 1,9 (IC95%: 1,2-2,9. El uso de catéter venoso central fue otro factor asociado tanto a la mortalidad cruda (RRa= 2,4; IC95%: 1,2- 4,8 como a la mortalidad atribuible (RRa= 3,8; IC95%: 1,6-8,8. Conclusiones. La producción de BLEE es un factor de riesgo independiente para mortalidad por bacteriemia causada por E. coli y Klebsiella spp. Su presencia debe evaluarse tras la sospecha diagnóstica y la elaboración de la terapéutica inicial, lo que podría disminuir la mortalidad por esta causaObjectives. To evaluate the factors associated to mortality caused by bacteremia due to Escherichia coli and Klebsiella spp. producers of extended-spectrum beta-lactamase (ESBL. Materials and methods. We performed a retrospective cohort study, including 85 patients older than 16 and diagnosed with bacteremia by Escherichia coli or Klebsiella spp

  1. Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana.

    Science.gov (United States)

    Rasmussen, Mette Marie; Opintan, Japheth A; Frimodt-Møller, Niels; Styrishave, Bjarne

    2015-01-01

    The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified as E. coli using MALDI-ToF. Of these 109 isolates were from meat whereas the remaining 44 were isolated from the cloaca of locally reared live chickens. Antimicrobial susceptibility test was done on the identified E. coli isolates. Additionally, beta-lactamases production (ESBL and/or AmpC) were phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP) E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported chickens (tetracycline 88.9% vs. 57.5%, sulphonamide 75.0% vs. 46.6%, ampicillin 69.4% vs. 61.6% and trimethoprim 66.7% vs. 38.4%). Beta-lactamase production was found in 29 E. coli meat isolates, with 56.9% of them being multiple drug resistant (≥ 3). The predominant phylogroup identified was B1 followed by A and D, with similar distribution among the isolates from meat of locally reared chickens and imported chickens. Beta-lactamase producing genotype blaCTX-M-15 (50%; 10/20) was the most frequently drug resistant gene detected. More BLP E. coli isolates were found in imported chicken meat compared to locally reared chickens, demonstrating that these isolates may be spreading through food trade. In conclusion, both imported and locally produced chicken meats are potential

  2. Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana.

    Directory of Open Access Journals (Sweden)

    Mette Marie Rasmussen

    Full Text Available The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified as E. coli using MALDI-ToF. Of these 109 isolates were from meat whereas the remaining 44 were isolated from the cloaca of locally reared live chickens. Antimicrobial susceptibility test was done on the identified E. coli isolates. Additionally, beta-lactamases production (ESBL and/or AmpC were phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported chickens (tetracycline 88.9% vs. 57.5%, sulphonamide 75.0% vs. 46.6%, ampicillin 69.4% vs. 61.6% and trimethoprim 66.7% vs. 38.4%. Beta-lactamase production was found in 29 E. coli meat isolates, with 56.9% of them being multiple drug resistant (≥ 3. The predominant phylogroup identified was B1 followed by A and D, with similar distribution among the isolates from meat of locally reared chickens and imported chickens. Beta-lactamase producing genotype blaCTX-M-15 (50%; 10/20 was the most frequently drug resistant gene detected. More BLP E. coli isolates were found in imported chicken meat compared to locally reared chickens, demonstrating that these isolates may be spreading through food trade. In conclusion, both imported and locally produced chicken meats

  3. Identification of Klebsiella pneumoniae strains harboring inactive extended-spectrum beta-lactamase antibiotic-resistance genes

    Institute of Scientific and Technical Information of China (English)

    Xu Li; Zhai Yao; Lyu Yuan; Wang Qi; An Shuchang; Chen Jichao; Chen Yusheng

    2014-01-01

    Background The extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae has increasingly become a major contributor to nosocomial infections and can exhibit multiple antibiotic resistance.Previous studies have focused on the resistance genes in ESBL-producing strains,and the resistance-associated genetic environment of non-ESBL-producing strains has been ignored until now.Here,we investigated the occurrence and characteristics of non-ESBL-producing K.pneumoniae,which potentially carries unexpressed resistance genes.Methods K.pneumoniae strains were collected from five medical institutions in China from February 2010 to August 2013.The VITEK-2 ESBL detection system was used as a primary screen to identify the ESBL-producing phenotype,and the three primary types of ESBL-associated genes (CTX,SHV,and TEM) were detected by polymerase chain reaction (PCR) to confirm the strains presenting with a non-ESBL-producing phenotype.mRNA expression in the non-ESBL-producing strains was further screened by reverse-transcription PCR (RT-PCR) to validate their transcriptional efficiency.Results Out of 224 clinically isolated antibiotic-sensitive K.pneumoniae strains with a non-ESBL-producing phenotype,5 (2.2%) were identified to carry inactivated ESBL blaSHV genes with intact upstream promoter regions and resistance gene sequences.Interestingly,three of the five antibiotic-sensitive K.pneumoniae strains containing ESBL blaSHV genes still exhibited mRNA transcription of blasHv,while the other two exhibited no mRNA transcription.Conclusion These findings suggest that inactivated ESBL genes exist in non-ESBL-producing antibiotic-sensitive K.pneumoniae strains,which have the potential to transform the strain into an ESBL phenotype if an inappropriate application or overdose of antibiotics is implemented during clinical management.

  4. Virulence of a Klebsiella pneumoniae strain carrying the New Delhi metallo-beta-lactamase-1 (NDM-1)

    DEFF Research Database (Denmark)

    Fuursted, Kurt; Schøler, Lone; Hansen, Frank;

    2011-01-01

    The aim of the study was to compare and evaluate virulence in five strains of Klebsiella pneumoniae, including an isolate carrying New Delhi metallo-beta-lactamase-1 (NDM-1). In vivo virulence was assessed using a murine sepsis model and using the nematode Caenorhabditis elegans killing model......, and in vitro virulence by assessing various virulence factors. The NDM-1 carrying K. pneumoniae isolate was the most virulent in the murine sepsis model but there was no clear cut correlation to in vitro virulence factors or killing in C. elegans. It is concluded that K. pneumoniae carrying NDM-1 have...

  5. Extended-spectrum-beta-lactamases, AmpC beta-lactamases and plasmid mediated quinolone resistance in klebsiella spp. from companion animals in Italy.

    Directory of Open Access Journals (Sweden)

    Valentina Donati

    Full Text Available We report the genetic characterization of 15 Klebsiella pneumoniae (KP and 4 isolates of K. oxytoca (KO from clinical cases in dogs and cats and showing extended-spectrum cephalosporin (ESC resistance. Extended spectrum beta-lactamase (ESBL and AmpC genes, plasmid-mediated quinolone resistance (PMQR and co-resistances were investigated. Among KP isolates, ST101 clone was predominant (8/15, 53%, followed by ST15 (4/15, 27%. ST11 and ST340, belonging to Clonal Complex (CC11, were detected in 2012 (3/15, 20%. MLST on KP isolates corresponded well with PFGE results, with 11 different PFGE patterns observed, including two clusters of two (ST340 and four (ST101 indistinguishable isolates, respectively. All isolates harbored at least one ESBL or AmpC gene, all carried on transferable plasmids (IncR, IncFII, IncI1, IncN, and 16/19 were positive for PMQR genes (qnr family or aac(6'-Ib-cr. The most frequent ESBL was CTX-M-15 (11/19, 58%, detected in all KP ST101, in one KP ST15 and in both KP ST340. blaCTX-M-15 was carried on IncR plasmids in all but one KP isolate. All KP ST15 isolates harbored different ESC resistance genes and different plasmids, and presented the non-transferable blaSHV-28 gene, in association with blaCTX-M-15, blaCTX-M-1 (on IncR, or on IncN, blaSHV-2a (on IncR or blaCMY-2 genes (on IncI1. KO isolates were positive for blaCTX-M-9 gene (on IncHI2, or for the blaSHV-12 and blaDHA-1 genes (on IncL/M. They were all positive for qnr genes, and one also for the aac(6'-Ib-cr gene. All Klebsiella isolates showed multiresistance towards aminoglycosides, sulfonamides, tetracyclines, trimethoprim and amphenicols, mediated by strA/B, aadA2, aadB, ant (2"-Ia, aac(6'-Ib, sul, tet, dfr and cat genes in various combinations. The emergence in pets of multidrug-resistant Klebsiella with ESBL, AmpC and PMQR determinants, poses further and serious challenges in companion animal therapy and raise concerns for possible bi-directional transmission between

  6. The role of beta-lactamase-producing-bacteria in mixed infections

    Directory of Open Access Journals (Sweden)

    Brook Itzhak

    2009-12-01

    Full Text Available Abstract Beta-lactamase-producing bacteria (BLPB can play an important role in polymicrobial infections. They can have a direct pathogenic impact in causing the infection as well as an indirect effect through their ability to produce the enzyme beta-lactamase. BLPB may not only survive penicillin therapy but can also, as was demonstrated in in vitro and in vivo studies, protect other penicillin-susceptible bacteria from penicillin by releasing the free enzyme into their environment. This phenomenon occurs in upper respiratory tract, skin, soft tissue, surgical and other infections. The clinical, in vitro, and in vivo evidence supporting the role of these organisms in the increased failure rate of penicillin in eradication of these infections and the implication of that increased rate on the management of infections is discussed.

  7. The revolving door between hospital and community: extended-spectrum beta-lactamase-producing Escherichia coli in Dublin.

    LENUS (Irish Health Repository)

    Burke, L

    2012-07-01

    Escherichia coli that produce extended-spectrum beta-lactamases (ESBLs) are an increasing cause of healthcare-associated infection, and community healthcare facilities may be a reservoir for important epidemic clones.

  8. Infections due to beta-lactamase-producing Neisseria gonorrhoeae at the University Hospital Medical Center, Kuala Lumpur, Malaysia.

    Science.gov (United States)

    Ismail, R

    1987-01-01

    The incidence of infections due to beta-lactamase-producing Neisseria gonorrhoeae is increasing in many parts of the world. An epidemiologic survey of infections caused by beta-lactamase-producing strains of N. gonorrhoeae at the University Hospital, Kuala Lumpur, from February 1977 to December 1985 (106 months) showed that the incidence rose from 4.8% (two cases) in 1977 to 49.4% (39 cases) by the end of 1985. The highest incidence of gonococcal infections was found to be in the group aged 20-39 years; the male-to-female ratio was 1.55:1. The mean inhibitory concentrations of benzylpenicillin were 0.12 microgram/ml for non-beta-lactamase-producing strains and 16 micrograms/ml for isolates of N. gonorrhoeae that produce beta-lactamase.

  9. Risk factors for and mortality of extended-spectrum-β-lactamase-producing Klebsiella pneumoniae and Escherichia coli nosocomial bloodstream infections Fatores de risco e mortalidade de infecções da corrente sanguínea por Klebsiella pneumoniae and Escherichia coli produtores de beta-lactamase de espectro estendido

    Directory of Open Access Journals (Sweden)

    Silvana Vargas Superti

    2009-08-01

    Full Text Available A case-control study, involving patients with positive blood cultures for Klebsiella pneumoniae (KP or Escherichia coli (EC EC and controls with positive blood cultures for non-ESBL-KP or EC, was performed to assess risk factors for extended-spectrum-β-lactamase (ESBL production from nosocomial bloodstream infections (BSIs. Mortality among patients with BSIs was also assessed. The study included 145 patients (81, 59.5% with K. pneumoniae and 64, 44.1% with E. coli BSI; 51 (35.2% isolates were ESBL producers and 94 (64.8% nonproducers. Forty-five (55.6% K. pneumoniae isolates were ESBL producers, while only six (9.4% E. coli isolates produced the enzyme. Multivariate analysis showed that recent exposure to piperacillin-tazobactam (adjusted Odds Ratio [aOR] 6.2; 95%CI 1.1-34.7 was a risk factor for ESBL BSI. K. pneumoniae was significantly more likely to be an ESBL-producing isolate than E. coli (aOR 6.7; 95%CI 2.3-20.2. No cephalosporin class was independently associated with ESBLs BSI; however, in a secondary model considering all oxymino-cephalosporins as a single variable, a significant association was demonstrated (aOR 3.7; 95%CI 1.3-10.8. Overall 60-day mortality was significantly higher among ESBL-producing organisms. The finding that piperacillin-tazobactam use is a risk factor for ESBL-production in KP or EC BSIs requires attention, since this drug can be recommended to limit the use of third-generation cephalosporins.Estudo de caso-controle, onde os casos foram pacientes com hemocultura positiva para Klebsiella pneumoniae (KP ou Escherichia coli (EC produtores de beta lactamase de espectro estendido (ESBL e os controles foram pacientes com hemoculturas positivas para EC ou KP não produtores de ESBL foi realizado para avaliar os fatores de risco para produção destas enzimas em infecções da corrente sanguínea (ICS. Mortalidade dos pacientes com ICS também foi avaliada. Foram incluídos 145 pacientes (81, 59,5% tinham Klebsiella

  10. Extended spectrum beta lactamase producing Proteus penneri: A rare missed pathogen?

    Directory of Open Access Journals (Sweden)

    Anita Pandey

    2014-01-01

    Full Text Available Indole negative Proteus species are invariably incorrectly identified as Proteus mirabilis, often missing out isolates of Proteus penneri. We report a case of extended spectrum beta lactamase producing and multidrug-resistant P. penneri isolated from pus from pressure sore of a patient of road traffic accident. Correct and rapid isolation and identification of such resistant pathogen are important as they are significant nosocomial threat.

  11. DISSEMINATION OF EXTENDED-SPECTRUM BETA-LACTAMASE PRODUCING ENTEROBACTERIACEAE IN CHILDREN

    OpenAIRE

    Lima, Sílvia Branco; Ferreira, Helena Neto

    2017-01-01

    Extended -spectrum beta-lactamase producing Enterobacteriaceae (EESBL), have been considered important nosocomial pathogens during the last decades. Nowadays community dissemination of this resistance threat is a reality, namely, in particular niches, as old people care settings. Fecal colonization of healthy people is a reality that might compromise effective infection control in acute care hospitals and long term care facilities and in that way, screening of extended -spectrum beta-lactamas...

  12. NDM-1 (New Delhi metallo beta lactamase-1 producing Gram-negative bacilli: Emergence & clinical implications

    Directory of Open Access Journals (Sweden)

    Bashir Ahmad Fomda

    2014-01-01

    Full Text Available Backgound & objectives: Resistance to carbapenems in Gram-negative bacteria conferred by NDM-1 is a global health problem. We investigated the occurrence of NDM-1 in clinical isolates of Gram-negative bacilli in a tertiary care hospital in Kashmir valley, India. Methods: Gram-negative bacilli from different clinical isolates were included in the study. Antimicrobial susceptibility was performed by Kirby Bauer disk diffusion method and interpreted using Clinical Laboratory Standards Institute (CLSI guidelines. Isolates resistant to carbapenems were subjected to different phenotypic test such as modified Hodge test (MHT, boronic acid and oxacillin based MHT ( BA-MHT and OXA-MHT, combined disk test and minimum inhibitory concentration (MIC with imipenem and imipenem -EDTA for determination of class B metallo enzymes. Presence of blaNDM-1 gene was established by PCR and confirmed by sequencing. Results: Of the total 1625 Gram-negative isolates received, 100 were resistant to imipenem. Of the 100 isolates, 55 (55% were positive by modified Hodge test indicating carbapenemase production. Of the 100 isolates tested by MHT, BA-MHT and OXA-MHT, 29 (29% isolates belonged to Class A and 15 (15% to Class B, while 56 (56% isolates were negative. Of the 15 class B metallo beta lactamase producers, nine carried the blaNDM-1 gene. NDM-1 was found among Escherichia coli (2 isolates, Klebsiella pneumoniae (2 isolates, Citrobacter freundii (3 isolates, Acinetobacter spp (1 isolate, and one isolate of Pseudomonas aeruginosa. Isolates were resistant to all antibiotic tested except polymyxin B and tigecycline. Interpretation & conclusions: Our study showed the presence of clinical isolates expressing NDM-1 in Srinagar, Jammu & Kashmir, India. These isolates harbour plasmid mediated multiple drug resistant determinants and can disseminate easily across several unrelated genera. To halt their spread, early identification of these isolates is mandatory.

  13. Extended-spectrum beta-lactamase- and carbapenemase-producing Enterobacteriaceae among Ethiopian children

    Science.gov (United States)

    Legese, Melese Hailu; Weldearegay, Gebru Mulugeta; Asrat, Daniel

    2017-01-01

    Background Infections by extended-spectrum beta-lactamase- (ESBL) and carbapenem-resistant Enterobacteriaceae (CRE) are an emerging problem in children nowadays. Hence, the aim of this study was to determine the prevalence of ESBL- and carbapenemase-producing Enterobacteriaceae among children suspected of septicemia and urinary tract infections (UTIs). Methods A cross-sectional study was conducted from January to March 2014. A total of 322 study participants suspected of septicemia and UTIs were recruited. All blood and urine samples were cultured on blood and MacConkey agar. All positive cultures were characterized by colony morphology, Gram stain, and standard biochemical tests. Antimicrobial susceptibility test was performed on Muller-Hinton agar using disk diffusion. ESBL was detected using combination disk and double-disk synergy methods, and the results were compared. Carbapenemase was detected by modified Hodge method using meropenem. Data were analyzed using SPSS version 20. Results The overall prevalence of ESBL- and carbapenemase-producing Enterobacteriaceae was 78.57% (n=22/28) and 12.12%, respectively. Among the Enterobacteriaceae tested, Klebsiella pneumoniae (84.2%, n=16/19), Escherichia coli (100%, n=5/5), and Klebsiella oxytoca (100%, n=1/1) were positive for ESBL. Double-disk synergy method showed 90.9% sensitivity, 66.7% specificity, 95.2% positive predictive value, and 50% negative predictive value. Carbapenemase-producing Enterobacteriaceae were K. pneumoniae (9.09%, n=3/33) and Morganella morganii (3.03%, n=1/33). Conclusion Screening Enterobacteriaceae for ESBL production is essential for better antibiotics selection and preventing its further emergence and spread. In resource-limited settings, double-disk synergy method can be implemented for screening and confirming ESBL production. Moreover, occurrence of CRE in countries where no carbapenems are sold is worrying microbiologists as well as clinicians. Hence, identifying factors that induce

  14. PER, CTX-M, TEM and SHV Beta-lactamases in Clinical Isolates of Klebsiella pneumoniae Isolated from Tehran, Iran

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    Leila Nasehi

    2010-06-01

    Full Text Available Objective(sDifferent types of extended spectrum beta-lactamases (ESBLs are encountered in the clinical settings worldwide. There are a few studies regarding the prevalence of ESBL genes among Klebsiella pneumoniae isolates at Tehran especially those of blaPER and blaCTX. The aim of this study was to determine the prevalence of blaSHV, blaTEM ,blaPER and blaCTX genes among clinical K. pneumoniae of different hospitals in Tehran.Materials and MethodsTwo hundred isolates of K. pneumoniae were received from different clinical specimens. The susceptibility of the isolates to 10 different antibiotics was examined by disk diffusion test. The MICs for ceftazidime were also determined using micro-broth dilution assay. Isolates showing MIC 4 μg/ml for ceftazidime were screened for ESBL production by phenotypic confirmatory test (PCT and subjected to PCR for studied genes. Variation among four amplified genes was evaluated using PCR-RFLP.ResultsBy disk diffusion test, resistance to ceftazidime and cefotaxime were 34.7% and 33.5% respectively. However, all strains were susceptible to imipenem. Eighty isolates showed MICs≥ 4 μg/ml for ceftazidime of which 77 (96% were positive for ESBL in PCT. The prevalence of blaSHV, blaCTX-M, blaTEM and blaPER among these isolates were 26%, 24.5%, 18% and 7.5%, respectively. No variation was detected in the genes by PCR-RFLP.ConclusionAs far as we know this is the first report of the blaPER-1 in K. pneumoniae in Iran. The blaCTX-M was the second most common gene detected among the ESBL positive isolates of K. pneumoniae. For rapid identification of ESBL producing isolates it was recommended that clinical laboratories adopt simple test based on CLSI recommendation for confirming ESBL production in enterobacterial species.

  15. Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana

    DEFF Research Database (Denmark)

    Rasmussen, Mette Marie; Opintan, Japheth A; Frimodt-Møller, Niels

    2015-01-01

    phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP) E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported......The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate...... whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified...

  16. Rapidly spreading CTX-M-type beta-lactamase-producing Proteus mirabilis in Japan.

    Science.gov (United States)

    Kanayama, Akiko; Iyoda, Takako; Matsuzaki, Kaoru; Saika, Takeshi; Ikeda, Fumiaki; Ishii, Yoshikazu; Yamaguchi, Keizo; Kobayashi, Intetsu

    2010-10-01

    In recent years, increased isolation of extended-spectrum beta-lactamase (ESBL)-producing Proteus mirabilis has been reported in Japan. We undertook an investigation to determine the prevalence of ESBL-producing P. mirabilis isolated in Japan and to characterise the genotype. Seventy-four P. mirabilis isolates recovered from specimens at 54 hospitals in Japan between March and October 2006 were included in the study. Of the 74 P. mirabilis isolates examined, 28 (37.8%) were ESBL-producers. The bla(CTX-M-2) gene was found in 27 isolates, whilst 1 isolate possessed bla(CTX-M-3). Amongst the 28 ESBL-producers, 25 (89.3%) were non-susceptible to ciprofloxacin, whilst 11 (23.9%) of 46 ESBL-non-producing isolates were non-susceptible to ciprofloxacin. Pulsed-field gel electrophoresis (PFGE) analysis of the 28 ESBL-producing isolates from 19 hospitals revealed 17 clusters. The same PFGE type was observed in two or more hospitals especially in the greater Tokyo area, suggesting possible clonal spread and the need for monitoring to determine whether emergence of a dominant clone occurs. Our results show that in Japan there is a high prevalence of CTX-M-type beta-lactamase-producing P. mirabilis. Moreover, these isolates are characterised by reduced susceptibility to fluoroquinolones.

  17. Regional variation in the prevalence of extended-spectrum beta-lactamase-producing clinical isolates in the Asia-Pacific region (SENTRY 1998-2002).

    Science.gov (United States)

    Hirakata, Yoichi; Matsuda, Junichi; Miyazaki, Yoshitsugu; Kamihira, Shimeru; Kawakami, Sayoko; Miyazawa, Yukihisa; Ono, Yasuo; Nakazaki, Nobuhiko; Hirata, Yasuyoshi; Inoue, Matsuhisa; Turnidge, John D; Bell, Jan M; Jones, Ronald N; Kohno, Shigeru

    2005-08-01

    We examined the prevalence of extended-spectrum beta-lactamase (ESBL)-producing strains of Klebsiella pneumoniae, Klebsiella oxytoca, Escherichia coli, Proteus mirabilis, Citrobacter koseri, and Salmonella spp. that were isolated as part of the SENTRY Asia-Pacific Surveillance Program between 1998 and 2002. During the study period, a total of 6,388 strains were gathered from 17 medical centers in 7 countries and examined for ESBL production and hyperproduction of K. oxytoca chromosomal K1 beta-lactamase enzyme. High rates of confirmed ESBL-producing isolates were found in K. pneumoniae strains from Singapore (35.6%), followed by those from mainland China (30.7%), South Africa (28.1%), and the Philippines (21.9%), whereas the rates were less than 10% in Japan and Australia. ESBL-producing E. coli strains were also prominent in mainland China (24.5%), Hong Kong (14.3%), and Singapore (11.3%). ESBL-producing K. oxytoca were common in the Philippines (38.5%), Singapore (33.3%), and China (30.0%). Hyperproduction of K. oxytoca chromosomal K1 beta-lactamase enzyme was common in Australia and Japan. P. mirabilis strains from Singapore produced ESBL (17.9%) despite the low prevalence (0-8.1%) in other countries. Few ESBL-producing C. koseri and Salmonella spp. strains were found in Japan, Singapore, Taiwan, and South Africa. Although there was variation among countries in substrate preference, ceftazidime was more likely to detect presumptive ESBL phenotype in K. pneumoniae and aztreonam more likely in E. coli, whereas ceftriaxone was the best substrate for the confirmation of ESBL production. ESBL-producing strains showed high levels of co-resistance to aminoglycosides, tetracycline, trimethoprim-sulfamethoxazole, and ciprofloxacin. Imipenem retained activity against all ESBL-producing strains. Organisms expressing ESBLs are widely distributed in the Asia-Pacific region, although prevalence rates vary significantly.

  18. Intravenous glucose preparation as the source of an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae infections in the neonatal unit of a regional hospital in KwaZulu-Natal.

    Science.gov (United States)

    Moodley, Prashini; Coovadia, Yacoob M; Sturm, A Willem

    2005-11-01

    In the last week of May 2005, staff at Mahatma Gandhi Memorial Hospital in KwaZulu-Natal realised that many babies in the high-care nursery ward had bloodstream infections involving Klebsiella pneumoniae bacteria. Attempts to identify a common source of infection failed. The ward was therefore closed and new babies needing high care were admitted to another empty ward. Despite this, babies still became infected. This resulted in a request for assistance from the Department of Medical Microbiology of the Nelson R Mandela School of Medicine. A search for common factors through case history studies of the 26 infected babies showed that blood cultures of the babies remained positive despite the administration of appropriate antibiotics. Different options that could explain this were investigated. The organism was found in intravenous glucose preparations used for multiple dosing. Unopened vials of the same medication were sterile. The nursery was found to lack proper hand-wash facilities and to be overcrowded and understaffed. Reinforcement of hand hygiene and a ban on the multiple dosing of medicines stopped the outbreak. In conclusion, this outbreak resulted from a combination of factors among which lack of hand hygiene and multiple dosing of an intravenous glucose preparation were most significant.

  19. 产AmpC酶肺炎克雷伯菌的耐药性及基因型研究%A study on resistance and genotypes of AmpC beta-lactamase producing Klebsiella pneumoniae in Anhui province

    Institute of Scientific and Technical Information of China (English)

    朱玉林; 高帆; 张晓妮; 程君; 殷俊; 李家斌; 叶英

    2009-01-01

    Objective To identify the plasmid-mediated AmpC gene and to investigate its prevalence in Klebsiella pneumoniae strains i-solated in Anhui Province. Methods The AmpC-preducing isolates were chosen by cefoxitin and identified by the three-dimensional test. The plasmid-mediated AmpC β-lactamases were detected by multiplex PCR. The PCR products were directly sequenced and ana-lyzed. M-H agar dilution method was used to determine MIC of 17 antimicrobial agents against the AmpC positive isolates. Results Of the 180 strains,21 (11.67%) proved to be plasmid-mediated highly productive AmpC by DNA sequence test. Blast results indicated that the positive AmpC group was composed of 17 strains which carried DHA type and 4 strains which carried EBC type. DNA sequence analysis revealed three novel AmpC genotypes ( GenBank accession: FJ237366, FJ237367, and FJ237368 ). All AmpC positive isolates exhibited high resistance to the third or fourth generation cephalosporins,aminoglycosides,and quinolones. But all of them were suscep-tible to imipenem and meropenem. Conclusions The plasmid-mediated AmpC β-lactamases were found in Klebsiella pneumoniae strains isolated in Anhui Province and DHA type was dominant. Moreover, three novel AmpC genotypes were identified. The carbapene-ms are recommended to treat the AmpC-preducing isolates.%目的 了解安徽地区产AmpC酶肺炎克雷伯菌的基因型特征及耐药性.方法 对180株肺炎克雷伯菌进行头孢西丁纸片法初筛,三维实验筛选高产AmpC酶茼,PCR扩增、测序和BLAST比对分析以确定AmpC基因型,琼脂稀释法检测耐药性.结果 产AmpC酶菌株有21株(11.67%),其中DHA型17株,EBC型4株.3株EBC型为新基因(gene bank登录号为FJ237366,FJ237367,FJ237368);药敏显示产酶株除对亚胺培南与美罗培南敏感外,对其他抗菌药物均有不同程度的耐药.结论 安徽地区产AmpC酶的肺炎克雷伯菌以DHA型为主,同时存在EBC型突变株.高产AmpC酶菌的感染推荐

  20. Predicting carriage with extended-spectrum beta-lactamase-producing bacteria at hospital admission : A cross-sectional study

    NARCIS (Netherlands)

    Platteel, T. N.; Leverstein-van Hall, M. A.; Cohen Stuart, J. W.; Thijsen, S. F T; Mascini, E. M.; van Hees, B. C.; Scharringa, J.; Fluit, A. C.; Bonten, M. J M

    2015-01-01

    The prevalence of patients colonized with extended-spectrum beta-lactamase (ESBL)-producing bacteria increases, especially in long-term-care facilities (LTCFs). Identification of ESBL carriers at hospital admission is relevant for infection control measures and antibiotic therapy for nosocomial infe

  1. Survey of metallo-beta-lactamase-producing Enterobacteriaceae colonizing patients in European ICUs and rehabilitation units, 2008-11

    NARCIS (Netherlands)

    Papagiannitsis, C. C.; Izdebski, R.; Baraniak, A.; Fiett, J.; Herda, M.; Hrabak, J.; Derde, L. P. G.; Bonten, M. J. M.; Carmeli, Y.; Goossens, H.; Hryniewicz, W.; Brun-Buisson, C.; Gniadkowski, M.

    2015-01-01

    Objectives: The objective of this study was to perform a multinational survey of patients' colonization by metallo-beta-lactamase (MBL)-producing Enterobacteriaceae, including their molecular characterization. Methods: Patients in 18 hospital units across Europe and Israel (n = 17945) were screened

  2. New Delhi metallo-beta-lactamase-1-producing Acinetobacter spp. infection: report of a survivor.

    Science.gov (United States)

    Schuelter-Trevisol, Fabiana; Schmitt, Graciane Jacinta; Araújo, Jane Martins de; Souza, Liliane Braga de; Nazário, Juliana Gomes; Januário, Raquel Landuchi; Mello, Rogério Sobroza de; Trevisol, Daisson José

    2016-02-01

    New Delhi metallo-beta-lactamase-1 (NDM-1) is a bacterial enzyme that renders the bacteria resistant to a variety of beta-lactam antibiotics. A 20-year-old man was hospitalized several times for surgical treatment and complications caused by a right-sided vestibular schwannoma. Although the patient acquired several multidrug-resistant infections, this study focuses on the NDM-1-producing Acinetobacter spp. infection. As it was resistant to all antimicrobials tested, the medical team developed a 20-day regimen of 750mg/day metronidazole, 2,000,000IU/day polymyxin B, and 100mg/day tigecycline. The treatment was effective, and the patient recovered and was discharged from the hospital.

  3. Extended spectrum beta-lactamase-producing Enterobacteriaceae in international travelers and non-travelers in New York City.

    Directory of Open Access Journals (Sweden)

    Scott A Weisenberg

    Full Text Available BACKGROUND: We performed this study 1 to determine the prevalence of community-associated extended spectrum beta-lactamase producing Enterobacteriaceae (ESBLPE colonization and infection in New York City (NYC; 2 to determine the prevalence of newly-acquired ESBLPE during travel; 3 to look for similarities in contemporaneous hospital-associated bloodstream ESBLPE and travel-associated ESBLPE. METHODS: Subjects were recruited from a travel medicine practice and consented to submit pre- and post-travel stools, which were assessed for the presence of ESBLPE. Pre-travel stools and stools submitted for culture were used to estimate the prevalence of community-associated ESBLPE. The prevalence of ESBLPE-associated urinary tract infections was calculated from available retrospective data. Hospital-associated ESBLPE were acquired from saved bloodstream isolates. All ESBLPE underwent multilocus sequence typing (MLST and ESBL characterization. RESULTS: One of 60 (1.7% pre- or non-travel associated stool was colonized with ESBLPE. Among community-associated urine specimens, 1.3% of Escherichia coli and 1.4% of Klebsiella pneumoniae were identified as ESBLPE. Seven of 28 travelers (25.0% acquired a new ESBLPE during travel. No similarities were found between travel-associated ESBLPE and hospital-associated ESBLPE. A range of imported ESBL genes were found, including CTX-M-14 and CTX-15. CONCLUSION: ESBL colonization and infection were relatively low during the study period in NYC. A significant minority of travelers acquired new ESBLPE during travel.

  4. Occurrence of bacteria producing broad-spectrum beta-lactamases and qnr genes in hospital and urban wastewater samples.

    Science.gov (United States)

    Röderová, Magdaléna; Sedláková, Miroslava Htoutou; Pudová, Vendula; Hricová, Kristýna; Silová, Romana; Imwensi, Peter Eghonghon Odion; Bardoň, Jan; Kolář, Milan

    2016-04-01

    The aims were to investigate the level of antibiotic-resistant bacteria in hospital and urban wastewater and to determine the similarity of isolates obtained from wastewater and hospitalized patients. Wastewater samples were collected in September 2013 and 2014. After identification using MALDI-TOF MS, beta-lactamase production was determined by relevant phenotypic tests. Genes responsible for the production of single beta-lactamase groups and Qnr proteins were established. The epidemiological relationship of the isolates from wastewater and hospitalized patients was determined by PFGE. A total of 51 isolates of enterobacteria were obtained. Overall, 45.1% of them produced broad-spectrum beta-lactamases. Genes encoding TEM, SHV, CTX-M, CIT, DHA and EBC types of enzymes and Qnr proteins were detected. No broad-spectrum beta-lactamase production was confirmed in the urban wastewater treatment plant. The most important finding was the detection of two identical isolates of K. pneumoniae in 2013, one from a patient's urinary catheter and the other from a wastewater sample.

  5. Exposure assessment of extended-spectrum beta-lactamases/AmpC beta-lactamases-producing Escherichia coli in meat in Denmark

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    Luís P. Carmo

    2014-02-01

    Full Text Available Introduction: Extended-spectrum beta-lactamases (ESBL and AmpC beta-lactamases (AmpC are of concern for veterinary and public health because of their ability to cause treatment failure due to antimicrobial resistance in Enterobacteriaceae. The main objective was to assess the relative contribution (RC of different types of meat to the exposure of consumers to ESBL/AmpC and their potential importance for human infections in Denmark. Material and methods: The prevalence of each genotype of ESBL/AmpC-producing E. coli in imported and nationally produced broiler meat, pork and beef was weighted by the meat consumption patterns. Data originated from the Danish surveillance program for antibiotic use and antibiotic resistance (DANMAP from 2009 to 2011. DANMAP also provided data about human ESBL/AmpC cases in 2011, which were used to assess a possible genotype overlap. Uncertainty about the occurrence of ESBL/AmpC-producing E. coli in meat was assessed by inspecting beta distributions given the available data of the genotypes in each type of meat. Results and discussion: Broiler meat represented the largest part (83.8% of the estimated ESBL/AmpC-contaminated pool of meat compared to pork (12.5% and beef (3.7%. CMY-2 was the genotype with the highest RC to human exposure (58.3%. However, this genotype is rarely found in human infections in Denmark. Conclusion: The overlap between ESBL/AmpC genotypes in meat and human E. coli infections was limited. This suggests that meat might constitute a less important source of ESBL/AmpC exposure to humans in Denmark than previously thought – maybe because the use of cephalosporins is restricted in cattle and banned in poultry and pigs. Nonetheless, more detailed surveillance data are required to determine the contribution of meat compared to other sources, such as travelling, pets, water resources, community and hospitals in the pursuit of a full source attribution model.

  6. Prevalence of extended spectrum beta lactamase and AmpC beta lactamase producers among Escherichia coli isolates in a tertiary care hospital in Jaipur

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    Sinha Parul

    2008-07-01

    Full Text Available Resistance to broad spectrum β lactams, mediated by extended spectrum beta lactamase (ESβL and AmpC βL enzymes is an increasing problem worldwide. Presence of these in clinical infections can result in treatment failure if one of the second or third generation cephalosporins is used. Therefore, it is recommended that any ESβL-producing organism according to the National Committee for Clinical Laboratory Standards (NCCLS criteria can be reported as resistant to all extended spectrum β lactam antibiotics regardless of the susceptibility test results. In this study, a total of 250 Escherichia coli (E. coli isolates were subjected to Double disc test and AmpC disc test for the detection of ESβL- and AmpC βL-producing strains, respectively. Prevalence of ESβL- and AmpC βL-producing strains among E. coli isolates, over a 3-month-period in the hospital-based population of Jaipur, was 64.80% (162/250. AmpC βL producers were 24.00% (60/250 and co-existence of ESβL and AmpC βL was detected in 8.00% (20/250 of the isolates.

  7. In vitro potentiation of carbapenems with ME1071, a novel metallo-beta-lactamase inhibitor, against metallo-beta-lactamase- producing Pseudomonas aeruginosa clinical isolates.

    Science.gov (United States)

    Ishii, Yoshikazu; Eto, Maki; Mano, Yoko; Tateda, Kazuhiro; Yamaguchi, Keizo

    2010-09-01

    ME1071, a maleic acid derivative, is a novel specific inhibitor for metallo-beta-lactamases (MBL). In this study, the potentiation of ME1071 in combination with several beta-lactams was evaluated using MBL-producing Pseudomonas aeruginosa isolates. The rates of susceptibility of MBL producers to carbapenems (imipenem, biapenem, and doripenem) and ceftazidime were increased by 8 to 27% in the presence of 32 microg/ml of ME1071. The corresponding resistance rates were decreased by 13 to 46%, respectively. On the other hand, ME1071 showed weaker or no potentiation with non-MBL producers. The K(i) value of ME1071 for IMP-1 was 0.4 microM, significantly lower than the K(m) values of carbapenems for the IMP-1 enzyme. On the other hand, the K(i) value of ME1071 for VIM-2 was 120 microM, higher than the K(m) values of carbapenems for the VIM-2 enzyme. Results of this study indicate that ME1071 can potentiate the activity of ceftazidime and carbapenems against MBL-producing strains of P. aeruginosa.

  8. Comparison of host response mechanisms evoked by extended spectrum beta lactamase (ESBL)- and non-ESBL-producing uropathogenic E. coli

    OpenAIRE

    2013-01-01

    Background Infections caused by extended spectrum beta-lactamases (ESBL)-producing bacteria have been emerging worldwide and the majority of ESBL-producing E. coli strains are isolated from patients with urinary tracts infections. The purpose of this study was to compare the host-response mechanisms in human polymorphonucleated leukocytes (PMN) and renal epithelial cells when stimulated by ESBL- or non-ESBL-producing uropathogenic E. coli (UPEC) isolates. The host-pathogen interaction of thes...

  9. Prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae isolated from blood cultures in Africa.

    Science.gov (United States)

    Sangare, S A; Maiga, A I; Guindo, I; Maiga, A; Camara, N; Savadogo, S; Diallo, S; Bougoudogo, F; Armand-Lefevre, L; Andremont, A; Maiga, I I

    2015-09-01

    Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have been isolated from many regions of the world. Epidemiological studies are being conducted in Europe, North America, and Asia. No study has however been conducted in Africa to determine the prevalence and distribution of ESBLs on the continent. This literature review aimed at describing the prevalence of ESBL-producing Enterobacteriaceae isolated from blood cultures, as well as the ESBL genes involved at the international level. Our focus was mainly on Africa. We conducted a literature review on PubMed. Articles related to our study field and published between 1996 and 2014 were reviewed and entirely read for most of them, while we only focused on the abstracts of some other articles. Relevant articles to our study were then carefully reviewed and included in the review. The prevalence of ESBL-producing Enterobacteriaceae differs from one country to another. The results of our literature review however indicate that class A ESBLs prevail over the other types. We took into consideration articles focusing on various types of samples to assess the prevalence of ESBL-producing Enterobacteriaceae, but information on isolates from blood cultures is limited. The worldwide prevalence of ESBL-producing Enterobacteriaceae has increased over time. Evidence of ESBL-producing Enterobacteriaceae can be found in all regions of the world. Studies conducted in Africa mainly focused on the Northern and Eastern parts of the continent, while only rare studies were carried out in the rest of the continent.

  10. Characteristics of bacteremia caused by extended-spectrum beta-lactamase-producing Proteus mirabilis.

    Science.gov (United States)

    Kurihara, Yoko; Hitomi, Shigemi; Oishi, Tsuyoshi; Kondo, Tsukasa; Ebihara, Tsugio; Funayama, Yasunori; Kawakami, Yasushi

    2013-10-01

    Although Proteus mirabilis is a common human pathogen, bacteremia caused by the organism, especially strains producing extended-spectrum beta-lactamase (ESBL), has rarely been investigated. We examined 64 cases of P. mirabilis bacteremia identified in the Minami Ibaraki Area, Japan, between 2001 and 2010 and compared the characteristics of cases with ESBL-producing and ESBL-non-producing strains (13 and 51 cases, respectively). All ESBL-producing strains with the gene encoding the CTX-M-2-group were genetically nonidentical. Isolation of ESBL-producing strains was significantly associated with onset in a hospital (p = 0.030), receiving hemodialysis (p = 0.0050), and previous antibiotic use within 1 month (p = 0.036; especially penicillin and/or cephalosporin (p = 0.010) and fluoroquinolone (p = 0.0069)). Isolation was also associated with inappropriate antibiotic therapy on the 1st and 4th days (p = 0.011 and 0.032, respectively) but not with mortality on the 30th day. These findings indicate that, for P. mirabilis bacteremia, isolation of ESBL-producing strains causes delay of initiating appropriate antimicrobial therapy but may not be associated with mortality.

  11. Molecular epidemiology of extended-spectrum beta-lactamase-producing Escherichia coli

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    Catherine Ludden

    2014-09-01

    Full Text Available Objectives: E. coli O25b-ST131 has disseminated worldwide in hospitals and the community. The objective of this study was to determine the extent to which E. coli O25b-ST131 accounts for extended-spectrum beta-lactamase (ESBLproducing E. coli from clinical samples from all sources in this region. Methods: Between January and June 2010 ESBL-producing E. coli were collected from 94 routine samples including 47 from residents of 25 nursing homes, 15 categorized as hospital acquired and 32 others. PCR was performed for detection of bla CTX-M, bla OXA-1, bla TEM, bla SHV and for the identification of members of the E. coli O25b:ST131 clonal group. PFGE was carried out using Xba I in accordance with PulseNet protocols. Results: The majority (97% of isolates harbored a bla CTX-M gene.E. coli O25b-ST131 accounted for 87% of all ESBL-producing E. coliand for 96% of isolates from nursing home residents. Conclusion:The E. coli O25b-ST131 clonal group predominated in the collection of ESBL-producing E. coli, particularly in nursing home isolates. J Microbiol Infect Dis 2014; 4(3: 92-96

  12. beta-Lactamase-producing Moraxella catarrhalis may prevent the emergence of penicillin-resistant Streptococcus pneumoniae in children with recurrent acute otitis media.

    Science.gov (United States)

    Joki-Erkkilä, Veli-Pekka; Aittoniemi, Janne; Vuento, Risto; Puhakka, Heikki

    2002-05-15

    We studied the effect of concomitant nasopharyngeal carriage of beta-lactamase producing Moraxella catarrhalis and Haemophilus influenzae on the occurrence of penicillin resistance of Streptococcus pneumoniae. We took nasopharyngeal samples from 306 children with recurrent otitis media and a history of several antibiotic treatments. We could isolate at least one of the pathogens in 89 subjects. Of these children 13% carried more than one pathogen. Of the isolated M. catarrhalis and H. influenzae strains 93% and 43% produced beta-lactamase, respectively. Of the S. pneumoniae strains 25% were non-susceptible (I/R) to penicillin. However, in patients carrying beta-lactamase-producing M. catarrhalis together with pneumococci all strains were susceptible to penicillin (P=0.0353). This finding suggests that beta-lactamase producing M. catarrhalis may hinder the emergence of penicillin resistance of S. pneumoniae in children with recurrent acute otitis media.

  13. Beta Lactamase Producing Clostridium perfringens Bacteremia in an Elderly Man with Acute Pancreatitis

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    Rashmi Mishra

    2016-01-01

    Full Text Available Clostridium perfringens bacteremia is associated with adverse outcomes. Known risk factors include chronic kidney disease, malignancy, diabetes mellitus, and gastrointestinal disease. We present a 74-year-old man admitted with confusion, vomiting, and abdominal pain. Exam revealed tachycardia, hypotension, lethargy, distended abdomen, and cold extremities. He required intubation and aggressive resuscitation for septic shock. Laboratory data showed leukocytosis, metabolic acidosis, acute kidney injury, and elevated lipase. CT scan of abdomen revealed acute pancreatitis and small bowel ileus. He was started on vancomycin and piperacillin-tazobactam. Initial blood cultures were positive for C. perfringens on day five. Metronidazole and clindamycin were added to the regimen. Repeat CT (day 7 revealed pancreatic necrosis. The patient developed profound circulatory shock requiring multiple vasopressors, renal failure requiring dialysis, and bacteremia with vancomycin-resistant enterococci. Hemodynamic instability precluded surgical intervention and he succumbed to multiorgan failure. Interestingly, our isolate was beta lactamase producing. We review the epidemiology, risk factors, presentation, and management of C. perfringens bacteremia. This case indicates a need for high clinical suspicion for clostridial sepsis and that extended spectrum beta lactam antibiotic coverage may be inadequate and should be supplemented with use of clindamycin or metronidazole if culture is positive, until sensitivities are known.

  14. A STUDY OF METALLO-BETA-LACTAMASE PRODUCING PSEUDOMONAS AERUGINOSA IN BLOOD SAMPLES OF BURNED PATIENTS

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    Piyali

    2014-11-01

    Full Text Available : BACKGROUND: Septicaemia is a life threatening complication of severely burned patients. Among many organisms invading blood stream Pseudomonas aeruginosa is a well-known for its powerful antibiotic resistance mechanisms which increasingly limit the choices for treatment. Among many such resistance mechanisms it is the metallo-beta-lactamase (MBL which confers resistance to Carbapenem group of antibiotics, one of the final resorts to fight them. The present study was undertaken to detect MBL producing P. aeruginosa using phenotypic method from blood samples of burned patients as well as to know their drug sensitivity pattern. MATERIALS AND METHODS: For this purpose 67 Pseudomonas aeruginosa isolates from blood samples of admitted burned patients were subjected to susceptibility testing to antipseudomonal drugs by disc diffusion test and those found to be Carbapenem resistant were subjected to Imipenem - EDTA combined disk synergy test for MBL detection. RESULT: Out of 67 isolates of P.aeruginosa, 19 (28.4% were found to be Carbapenem resistant and 11 (16.4% were MBL producers. A particularly important feature was that the MBL producers were highly resistant to the antibiotics tested than the non-producers. However all of them were susceptible to Colistin and Polymixin B. CONCLUSION: This study has made us to think that a constant vigil and careful selection of antibiotics are necessary to keep prevalence of MBL producing P.aeruginosa in check. The accurate identification and reporting of MBL producing P. aeruginosa will aid infection control practitioners in preventing the spread of these multidrug-resistant isolates

  15. Community faecal carriage of extended-spectrum beta-lactamase-producing Enterobacteriaceae in french children

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    Birgy André

    2012-11-01

    Full Text Available Abstract Background The increasing incidence of community acquired infection due to Extended-Spectrum Beta-Lactamase (ESBL -Producing Enterobacteriaceae represent a great concern because there are few therapeutic alternatives. The fecal flora of children in the community can represent a reservoir for ESBLs genes which are located on highly transmissible plasmids and the spread of these genes among bacterial pathogens is concerning. Because intestinal carriage is a key factor in the epidemiology of ESBL-producing Enterobacteriaceae, the study of the prevalence of these resistant bacteria and risk factors in young children is of particular interest. Methods We assessed the prevalence and risk factors of community-acquired faecal carriage of extended-spectrum-β-lactamase (ESBL-producing Enterobacteriaceae in children aged from 6 to 24 months, by means of rectal swabbing in community pediatric practices. Child’s lifestyle and risk factors for carriage of resistant bacteria were noted. Results Among the 411 children enrolled, 4.6% carried ESBL-producing Enterobacteriaceae. CTX-M-1, CTX-M-15 and CTX-M-14 were the predominant ESBLs. The 18 E. coli isolates were genetically heterogeneous. Recent third-generation oral-cephalosporin exposure was associated with a higher risk of ESBL carriage (AOR=3.52, 95% CI[1.06-11.66], p=0.04. Conclusions The carriage rate of ESBL-producing Enterobacteriacae in young children in the French community setting is noteworthy, underlining the importance of this population as a reservoir. Exposure to third-generation oral cephalosporins was associated with a significant risk of ESBL carriage in our study. Because of the significant public health implications including the treatment of community-acquired urinary tract infections, the spread of organisms producing ESBLs in the community merits close monitoring with enhanced efforts for surveillance.

  16. Reduced Susceptibility to Cefepime in Clinical Isolates of Enterobacteriaceae Producing OXA-1 Beta-Lactamase.

    Science.gov (United States)

    Torres, Eva; López-Cerero, Lorena; Rodríguez-Martínez, José Manuel; Pascual, Álvaro

    2016-03-01

    An increase of Enterobacteriaceae isolates with reduced susceptibility to cefepime (FEP) and amoxicillin/clavulanate (AMC) has been observed in our area. The aim of this study was to characterize this antibiotic resistance phenotype and its molecular epidemiology. A total of 33 Enterobacteriaceae strains were studied. blaOXA-1 genes and their genetic environment were analyzed by polymerase chain reaction (PCR) and sequencing. Plasmids were transferred by conjugation and/or transformation and classified using PCR-based inc/rep typing and IncF subtyping. Escherichia coli isolates were typed by phylogroup, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Outer membrane proteins were studied by sodium dodecylsulfate-polyacrylamide gel electrophoresis and expression of blaOXA-1 genes by reverse transcription-PCR. FEP minimum inhibitory concentration yielded values of 1-16 mg/L. Twenty-nine (87.9%) isolates produced OXA-1, of which 24 (82.7%) were located in class 1 integron, and 9 (27.3%) produced TEM-1. Among the 24 E. coli OXA-1-producers, PFGE revealed two main clusters: one belonged to C-ST88 and the other to B23-ST131. Thirteen plasmids containing blaOXA-1 were transferred, nine belonged to IncF replicon (4 F2:A1:B-, 2 F1:A1:B1, 1 F1:A2:B-, 1 F18:A2:B1, 1 F5:A-:B1) and four were nontypeable. In conclusion, reduced susceptibility to FEP was mostly due to OXA-1 beta-lactamase. In E. coli, this increase is mainly due to the dissemination of two clones, which have captured different IncF plasmids. Among non-E. coli strains, five isolates produced OXA-1 and one isolate produced only TEM-1.

  17. Avaliação da acurácia de testes laboratoriais para detecção de amostras de Klebsiella pneumoniae produtora de betalactamase de espectro estendido Comparison of different methods for detection of Klebsiella pneumoniae isolates producers of extended spectrum beta-lactamase

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    Andrea dos Santos Pereira

    2003-01-01

    spectrum beta-lactamases (ESBL represent a common resistance problem among Brazilian hospitals. Due to the difficulty of ESBL detection in the clinical laboratory, these bacterial isolates require a reproducible, efficient, and low cost detection method. The aim of the present study was to evaluate the efficacy of detection of K. pneumoniae ESBL isolates by two methods: the Etest ESBL strip and the inhibitor potentiated disk diffusion test with clavulanic acid (clavulanate-potentiation test. The sensitivity and the specificity of beta-lactam agents against these isolates were also evaluated. The experiments were performed on a total of 134 K. pneumoniae isolates recovered from blood specimens in our institution from July 1996 to July 2001. The samples were tested for ESBL production by the NCCLS screen test, clavulanate-potentiation test and Etest ESBL strip. Isolates presenting positive results for the screen test and for at least one of the evaluated tests were considered ESBL producers (gold standard. The results of this study yielded a 100% specificity and sensitivity for the clavulanate-potentiation test, and the best indicators of ESBL production were cefotaxime and cefpodoxime. The Etest ESBL strip also turned out to be a very sensitive (96% and specific (100% method, being cefotaxime the most efficient substrate. According to the results of this investigation, the clavulanate potentiation disk diffusion test displayed an excellent performance and can be easily implemented in routine clinical laboratories as a practical, reliable, and accurate method.

  18. Antibacterial Activity of Some Plant Extracts Against Extended- Spectrum Beta-Lactamase Producing Escherichia coli Isolates

    Science.gov (United States)

    Saeidi, Saeide; Amini Boroujeni, Negar; Ahmadi, Hassan; Hassanshahian, Mehdi

    2015-01-01

    Background: The extended-spectrum beta-lactamase (ESBL) -producing Escherichia coli isolates make many serious infections, especially urinary tract infections. Objectives: The purpose of this study was to determine the antibacterial activities of some natural plant extracts against ESBL-producing E. coli isolates, which harbor the TEM gene in urine samples of the patients who have urinary tract infections. Materials and Methods: Evaluation has to be exactly determined for both methods of disk diffusion test and polymerase chain reaction (PCR), separately. We evaluated 120 strains of E. coli isolates from the urine culture of the patients in Boo-Ali Hospital (Zahedan, south-eastern Iran) who were suffering from urinary tract infections. The ESBL-producing E. coli isolates were evaluated by disk diffusion test and PCR through TEM gene detection. The minimal inhibitory concentration (MIC) of commonly used antibiotics including ceftazidime, ceftriaxon, amikacin, gentamicin and ciprofloxacin along with the MIC of the alcoholic extract of different natural plants including Myrtus communis L (Myrtaceae), Amaranthus retraflexus (Amaranthaceae), Cyminum cuminum L (Apiaceae), Marrubium vulgare (Laminaceae) and Peganum. harmala (Zygrophyllaceae) against the ESBL-producing E. coli isolates, which harbor the TEM genes, were determined using the microdulition method. Results: Results of this study showed that in disk diffusion method, 80 samples of E. coli produced ESBLs. In PCR method, the TEM gene distribution in the isolated ESBL-producing organisms was 50 (41.6%). Amikacin was the most effective anti-bacterial agent and ciprofloxacin was the least effective against E. coli isolates. All the natural plant extracts mentioned above, especially P. harmala, were effective against the selected isolates of ESBL-producing E. coli. The most frequent ESBL rate producing E. coli isolates (32 out of 50) had MIC of 2.5 mg/mL in ethanol extract of P. harmala. Conclusions: The alcoholic

  19. Characterization of a new TEM-derived beta-lactamase produced in a Serratia marcescens strain.

    OpenAIRE

    Perilli, M.; Felici, A.; Franceschini, N; De Santis, A; Pagani, L.(Physics Department, Università degli Studi and INFN, 16146 Genova, Italy); Luzzaro, F.; Oratore, A; Rossolini, G. M.; Knox, J R; Amicosante, G

    1997-01-01

    A natural TEM variant beta-lactamase was isolated from an epidemic strain of Serratia marcescens. Nucleotide gene sequencing revealed multiple point mutations located in the 42-to-44 tripeptide and positions 145 to 146, 178, and 238. In addition, a glutamic acid 212 deletion was also found. The purified enzyme was studied from a kinetic point of view, revealing the highest catalytic efficiency (k[cat]/Km) values for ceftazidime and aztreonam compared with the TEM-1 prototype enzyme. The in vi...

  20. Characteristics of extended-spectrum β-lactamase (ESBL)- and pAmpC beta-lactamase-producing Enterobacteriaceae of water samples in Tunisia.

    Science.gov (United States)

    Ben Said, Leila; Jouini, Ahlem; Alonso, Carla Andrea; Klibi, Naouel; Dziri, Raoudha; Boudabous, Abdellatif; Ben Slama, Karim; Torres, Carmen

    2016-04-15

    The presence of extended-spectrum beta-lactamase and plasmid-mediated AmpC beta-lactamase producing Enterobacteriaceae (ESBL-Eb and pAmpC-Eb, respectively) was analyzed in 57 wastewater and 57 surface-water samples in Tunisia. Twenty-four of the 57 wastewater samples (42.1%) and one of the 57 surface-water samples (1.7%, a river that received effluents of a wastewater-treatment-plant) contained ESBL-Eb or pAmpC-Eb; one ESBL/pAmpC-Eb per positive sample was further characterized. Beta-lactamase genes detected were as follows: blaCTX-M-1 (10 Escherichia coli),blaCTX-M-15 (eight E. coli, one Klebsiella pneumoniae, one Citrobacter freundii), blaCTX-M-14 (one E. coli) and blaCMY-2 (four E. coli). The blaTEM-1, blaOXA-1 or blaSHV-1 genes were also found in 72% of these isolates. The ISEcp1, orf477 or IS903 sequences were found upstream or downstream of blaCTX-M genes. Class 1 integrons were present in 16 of the 25 ESBL-Eb/pAmpC-Eb strains (64%), and contained five different gene-cassette arrays. Most of the strains (76%) showed a multiresistant phenotype and qnr genes were identified in four strains. Molecular typing of ESBL/CMY-2-producing E. coli isolates showed 23 different PFGE-patterns and 15 different sequence-types (ST10, ST46, ST48, ST58, ST69, ST101, ST117, ST131, ST141, ST288, ST359, ST399, ST405, ST617, and the new ST4530); these strains were ascribed to phylogroups A (11 isolates), B1 (3 isolates), D (6 isolates) and B2 (3 isolates). From one to five plasmids were detected in each strain (size from 30kb to >240kb) and ESBL or pAmpC genes were transferred by conjugation in 69.5% of the E. coli strains. In conclusion, ESBL-Eb and pAmpC-Eb strains are frequently detected in wastewater samples and they might be a source for dissemination in other environments with repercussion in public health.

  1. Burden of different beta-lactamase classes among clinical isolates of AmpC-producing Pseudomonas aeruginosa in burn patients: A prospective study

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    V Kumar

    2012-01-01

    Full Text Available Background: Pseudomonas aeruginosa is one of the most common pathogens causing infections in burns, and shows increasing resistance to β-lactam antibiotics by producing different classes of beta-lactamases. It is also not unusual to find a single isolate that expresses multiple β-lactamase enzymes, further complicating the treatment options. Thus, in this study, we aimed to determine the coexistence of different beta-lactamase enzymes in clinical isolates of P. aeruginosa in the burn ward. Materials and Methods: A total of 101 clinical isolates of P. aeruginosa from the burn ward were identified and tested for the presence of different beta-lactamase enzymes (extended spectrum beta lactamase (ESBL, Amp C and metallo β-lactamases (MBL from October 2006 to May 2009. In vitro susceptibility pattern of antipseudomonal antibiotics was done by the Kirby Bauer disc diffusion method. Results: A total of 33 (32.7% isolates were confirmed to be positive for AmpC beta-lactamase. Co-production of AmpC along with ESBL and MBL was reported in 24.5% and 45.5% isolates, respectively. A total of 12 (11.9% isolates were resistant to three or more antibiotic classes (multidrug resistance. Imipenem and piperacillin/tazobactum showed high sensitivity, with 86.1% and 82.2%, respectively. Conclusion: This study reveals the high prevalence of multidrug- resistant P. aeruginosa producing beta-lactamase enzymes of different mechanisms in this region from burn patients. The emerging antimicrobial resistance in burn wound pathogens poses serious therapeutic challenge. Thus proper antibiotic policy and measures to restrict the indiscriminate use of cephalosporins and carbapenems should be taken to minimize the emergence of this multiple beta -lactamase producing pathogen.

  2. Zero prevalence of extended spectrum beta-lactamase-producing bacteria in 300 breeding Collared Flycatchers in Sweden

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    Josef D. Järhult

    2013-07-01

    Full Text Available Wild birds are important indicators and potential spreaders of antibiotic resistance. The order Passerines is scarcely studied apart from Corvus sp. but extended spectrum beta-lactamases (ESBLs has been found in Blackbirds. We tested 300 fecal samples from a well-studied population of Collared Flycatchers (Ficedula albicollis at the Island of Gotland in Sweden and found no ESBL-producing bacteria. These results support the idea of ‘ecological guild’ as Blackbirds are ground-foraging invertebrate feeders, whereas Collared Flycatchers are aerial insectivores not regularly coming into contact with fecal contaminations and therefore less prone to acquire pathogens spread by the fecal–oral route.

  3. In vivo development of carbapenem resistance in clinical isolates of Enterobacter aerogenes producing multiple beta-lactamases.

    Science.gov (United States)

    Chen, Ya-Gang; Zhang, Ying; Yu, Yun-Song; Qu, Ting-Ting; Wei, Ze-Qing; Shen, Ping; Li, Lan-Juan

    2008-10-01

    Four clinical strains of extended-spectrum beta-lactamase- and AmpC-producing Enterobacter aerogenes were isolated successively from a liver transplantation patient. Isolates C(1) and C(2) were isolated prior to carbapenem therapy, whilst isolates C(3) and C(4) were recovered after 40 days of carbapenem therapy. The homology of these strains was analysed by pulsed-field gel electrophoresis (PFGE). beta-Lactamases were analysed by isoelectric focusing, polymerase chain reaction (PCR) and sequencing. Outer membrane proteins were analysed by PCR, sequencing, sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blot. Disruption of OmpE36 in C(1) in vitro was also performed by homologous gene recombination. The isolates demonstrated an indistinguishable PFGE pattern. Molecular characterisation revealed that, in addition to the pre-existing multiple beta-lactamases (DHA-1, TEM-1, SHV-5, CTX-M-3 and CTX-M-14) found in C(1) and C(2), isolates C(3) and C(4) failed to express OmpE36 owing to insertional inactivation by an IS903-like insertion sequence. Other resistance mechanisms, such as production of carbapenem-hydrolysing enzymes or expression of chromosomal efflux, were apparently not involved. Completely replacing OmpE36 by the kanamycin resistance gene (kan) resulted in a significant increase in carbapenem minimum inhibitory concentrations of an ompE36 mutant. Thus, C(3) and C(4) were apparently derived from the previously imipenem-susceptible isolates C(1) and C(2). Following carbapenem exposure, depletion of OmpE36 expression resulted in the collateral effect of carbapenem resistance.

  4. Meta-analysis of proportion estimates of Extended-Spectrum-Beta-Lactamase-producing Enterobacteriaceae in East Africa hospitals

    DEFF Research Database (Denmark)

    Sonda, Tolbert; Kumburu, Happiness; van Zwetselaar, Marco;

    2016-01-01

    Background: A high proportion of Extended-Spectrum-Beta-Lactamase (ESBL) producing Enterobacteriaceae is causing common infections in all regions of the world. The burden of antibiotic resistance due to ESBL in East Africa is large but information is scarce and thus it is unclear how big the prob......Background: A high proportion of Extended-Spectrum-Beta-Lactamase (ESBL) producing Enterobacteriaceae is causing common infections in all regions of the world. The burden of antibiotic resistance due to ESBL in East Africa is large but information is scarce and thus it is unclear how big...... the problem really is. To gain insight into the magnitude and molecular epidemiology of ESBL-producing Enterobacteriaceae in East Africa a literature search was performed in PubMed on 31 July 2015 to retrieve articles with relevant information on ESBL. Methods and results: Meta-analysis was performed...... to determine overall proportion estimate of ESBL-producing Enterobacteriaceae. A total of 4076 bacterial isolates were included in the analysis. The overall pooled proportion of ESBL-producing Enterobacteriaceae among included surveys done in East African hospitals was found to be 0. 42 (95 % CI: 0...

  5. Prevalence and antimicrobial susceptibility of extended-spectrum beta-lactamase producing urinary isolates of Escherichia coli in outpatients

    Directory of Open Access Journals (Sweden)

    Marković Tatjana

    2013-01-01

    Full Text Available Introduction. In Gram-negative bacteria, the production of beta-lactamases is the most important mechanism of resistance to beta-lactam antibiotics. In the Banja Luka region, there were no extensive researches on the prevalence and antimicrobial resistance of the extended-spectrum beta-lactamase (ESBL producing Escherichia coli (E. coli isolates. Objective. The aim of the present study was to determine the presence of ESBL producing E. coli isolates as the cause of the urinary tract infections in outpatients, the distribution of these ESBL isolates according to age and gender of patients and their susceptibility to antimicrobials. Methods. Urine specimens obtained from outpatients were cultured on chromogenic CPS-ID3 media. All plates showing significant (>105 cfu/ml growth of E. coli in pure culture were further processed. Antimicrobial susceptibility testing was performed on VITEK TWO Compact using AST-GN27 cards for testing Gram negative bacteria and detection of ESBL producers. Results. Out of 2,195 isolates, 177 (8.1% were ESBL producers. Ninety-two isolates were obtained from female patients (5% of E. coli isolated from women and 85 isolates from male patients (23% of E. coli isolated from men. High percentage of ESBL isolates was detected in the infant age group under one year (36.7% and in the age group over 60 years (28.8%. All ESBL isolates were susceptible to imipenem and resistant to ampicillin, piperacillin, cefazolin, cefotaxime, ceftazidime and cefepime. There was a significant resistance to amikacin (79.1%, gentamicin (76.8%, amoxicillin/clavulanate (54.8% and trimethoprim/sulphamethoxazole (45.8%. Resistance to nutrofurantoin was 13.6%. Conclusion. This study has demonstrated the presence of ESBL producing E. coli urinary isolates in outpatients, and their extensive susceptibility to imipenem and nitrofurantoin.

  6. Recurrent extended-spectrum beta-lactamase-producing Escherichia coli urinary tract infection due to an infected intrauterine device.

    Science.gov (United States)

    Hui, Chee-Kin

    2014-02-01

    The use of intrauterine devices (IUDs) have been widespread since the 1960s. In 2002, the World Health Organization estimated that approximately 160 million women worldwide use IUDs. However, IUDs are associated with short-term complications such as vaginal bleeding, pelvic discomfort, dyspareunia and pelvic infection. Herein, we report the case of a woman who had recurrent urinary tract infection (UTI) due to the use of an IUD, even after treatment. The patient developed four episodes of UTI within a seven-month period after IUD insertion. During each episode of UTI, extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) was cultured from the patient’s midstream urine. The IUD was finally removed, and culture of the removed IUD was positive for ESBL-producing E. coli. An infected IUD as a source of recurrent UTI should be considered in women with IUD in situ who develop recurrent UTI even after treatment.

  7. Silver nanoparticle production by Rhizopus stolonifer and its antibacterial activity against extended spectrum {beta}-lactamase producing (ESBL) strains of Enterobacteriaceae

    Energy Technology Data Exchange (ETDEWEB)

    Banu, Afreen [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India); Rathod, Vandana, E-mail: drvandanarathod@rediffmail.com [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India); Ranganath, E. [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India)

    2011-09-15

    Highlights: {yields} Silver nanoparticle production by using Rhizopus stolonifer. {yields} Antibacterial activity of silver nanoparticles against extended spectrum {beta}-lactamase producing (ESBL) strains of Enterobacteriaceae. {yields} Synergistic effect of antibiotics with silver nanoparticles towards ESBL-strains. {yields} Characterization of silver nanoparticles made by UV-vis spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) spectroscopy, atomic force microscopy (AFM). -- Abstract: This report focuses on the synthesis of silver nanoparticles using the fungus, Rhizopus stolonifer and its antimicrobial activity. Research in nanotechnology highlights the possibility of green chemistry pathways to produce technologically important nanomaterials. Characterization of newly synthesized silver nanoparticles was made by UV-visible absorption spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and atomic force microscope (AFM). TEM micrograph revealed the formation of spherical nanoparticles with size ranging between 3 and 20 nm. The biosynthesized silver nanoparticles (AgNPs) showed excellent antibacterial activity against ESBL-strains which includes E. coli, Proteus. sp. and Klebsiella sp.

  8. Transmission of an extended-spectrum-beta-lactamase-producing Escherichia coli (sequence type ST131) strain between a father and daughter resulting in septic shock and Emphysematous pyelonephritis.

    Science.gov (United States)

    Ender, Peter T; Gajanana, Deepakraj; Johnston, Brian; Clabots, Connie; Tamarkin, Frank J; Johnson, James R

    2009-11-01

    Probable transmission of an extended-spectrum-beta-lactamase-producing Escherichia coli strain (sequence type ST131) between a father and daughter was documented. The father developed severe, recurrent pyelonephritis with multiple small abscesses; the daughter later developed septic shock, bacteremia, and extensive emphysematous pyelonephritis. This multidrug-resistant E. coli clone appears to be highly pathogenic and transmissible.

  9. Clinical impact and risk factors for colonization with extended-spectrum beta-lactamase-producing bacteria in the intensive care unit

    NARCIS (Netherlands)

    Razazi, Keyvan; Derde, Lennie P. G.; Verachten, Marine; Legrand, Patrick; Lesprit, Philippe; Brun-Buisson, Christian

    2012-01-01

    The changed epidemiology of extended spectrum beta-lactamases (ESBL), the spread to the community and the need for prudent use of carbapenems require updated knowledge of risk factors for colonization with ESBL-producing enterobacteriaceae (ESBL-PE). An 8-month prospective study in the medical ICU o

  10. Monobactam and aminoglycoside combination therapy against metallo-beta-lactamase-producing multidrug-resistant Pseudomonas aeruginosa screened using a 'break-point checkerboard plate'.

    Science.gov (United States)

    Araoka, Hideki; Baba, Masaru; Takagi, Shinsuke; Matsuno, Naofumi; Ishiwata, Kazuya; Nakano, Nobuaki; Tsuji, Masanori; Yamamoto, Hisashi; Seo, Sachiko; Asano-Mori, Yuki; Uchida, Naoyuki; Masuoka, Kazuhiro; Wake, Atsushi; Taniguchi, Shuichi; Yoneyama, Akiko

    2010-03-01

    Metallo-beta-lactamase-producing multidrug-resistant Pseudomonas aeruginosa (MDR P. aeruginosa) is a cause of life-threatening infections. With parenteral colistin not available in Japan, we treated MDR P. aeruginosa sepsis with monobactam and aminoglycoside combination therapy, with screening using a 'break-point checkerboard plate'.

  11. Enhanced synergism of antibiotics with zinc oxide nanoparticles against extended spectrum {beta}-lactamase producers implicated in urinary tract infections

    Energy Technology Data Exchange (ETDEWEB)

    Bhande, Rashmi M., E-mail: bhanderashmi@gmail.com; Khobragade, C. N., E-mail: profcnkbt@rediffmail.com [Swami Ramanand Teerth Marathwada University, School of Life Sciences (India); Mane, R. S., E-mail: rsmane@rediffmail.com; Bhande, S., E-mail: sambhajibhande@gmail.com [Swami Ramanand Teerth Marathwada University, School of Physical Sciences (India)

    2013-01-15

    In this study, enhanced synergistic bioactivity of zinc oxide nanoparticles (ZnO NPs) with {beta}-lactam antibiotics were evaluated against a panel of clinically isolated extended spectrum {beta}-lactamase producers implicated in urinary tract infections. Chemically synthesized zinc oxide nanoparticles (15 nm) were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmittance electron microscopy (HR-TEM), selective area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), and UV-Visible spectrophotometry techniques. The antimicrobial potency (10 {+-} 0.66, 12, 11.33 {+-} 1.10, and 0.7 {+-} 0.66 mm inhibiting zone) and minimum inhibitory concentrations (80, 60, 30, 50 {mu}g/ml) of ZnO NPs were tested separately whereas time-kill and membrane leakage assays were evaluated in combination with ZnO NPs+ cefotaxime, ampicillin, ceftriaxone, cefepime against the {beta}-lactamase producer strains of E. coli, K. pneumoniae, S. paucimobilis, and P. aeruginosa, respectively. Time-kill curve dynamics of ZnO NPs with {beta}-lactam antibiotics revealed enhanced bactericidal activity (50, 85, 58, 50 % fold inhibition) by delaying the exponential and stationary phases of all isolates when tested separately. Posttime-kill effect was studied on cell membrane by assaying leakage of reducing sugars (130.2, 124.7, 137, and 115.8 {mu}g/bacterial dry weight of 1 mg ({mu}g/mg) and proteins (15, 10, 16, 18 {mu}g/mg). These assays revealed that membrane leakage was due to synergism of ZnO NPs+ {beta}-lactam antibiotics which successfully damage cell membrane thereby leading to death of all ESBL producers. The results demonstrate the utilization of ZnO NPs as a potentiator of {beta}-lactam antibiotics and suggest the possibility to use nanoparticles in a combination therapy to treat UTI.

  12. Extended spectrum beta-lactamase-producing Escherichia coli forms filaments as an initial response to cefotaxime treatment

    DEFF Research Database (Denmark)

    Kjeldsen, Thea S. B.; Sommer, Morten Otto Alexander; Olsen, John E.

    2015-01-01

    Background: beta-lactams target the peptidoglycan layer in the bacterial cell wall and most beta-lactam antibiotics cause filamentation in susceptible Gram-negative bacteria at low concentrations. The objective was to determine the initial morphological response of cephalosporin resistant CTX-M-1......-17 hours in cultures of the resistant strains. Filaments were also observed in sensitive control strains with sub-inhibitory concentrations of cefotaxime. Conclusions: We showed that E. coli resistant to beta-lactams by an extended-spectrum beta-lactamase, bla(CTX-M-1), produced filaments when exposed...... to cefotaxime. The filament formation was restricted to early growth phases and the time the cells grew as filaments was antibiotic concentration dependent. This indicates that antibiotic resistant E. coli undergo the same morphological changes as sensitive bacteria in the presence of beta-lactam antibiotic...

  13. Empiric Piperacillin-Tazobactam versus Carbapenems in the Treatment of Bacteraemia Due to Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae.

    Science.gov (United States)

    Ng, Tat Ming; Khong, Wendy X; Harris, Patrick N A; De, Partha P; Chow, Angela; Tambyah, Paul A; Lye, David C

    2016-01-01

    Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are a common cause of bacteraemia in endemic countries and may be associated with high mortality; carbapenems are considered the drug of choice. Limited data suggest piperacillin-tazobactam could be equally effective. We aimed to compare 30-day mortality of patients treated empirically with piperacillin-tazobactam versus a carbapenem in a multi-centre retrospective cohort study in Singapore. Only patients with active empiric monotherapy with piperacillin-tazobactam or a carbapenem were included. A propensity score for empiric carbapenem therapy was derived and an adjusted multivariate analysis of mortality was conducted. A total of 394 patients had ESBL-Escherichia.coli and ESBL-Klebsiella pneumoniae bacteraemia of which 23.1% were community acquired cases. One hundred and fifty-one received initial active monotherapy comprising piperacillin-tazobactam (n = 94) or a carbapenem (n = 57). Patients who received carbapenems were less likely to have health-care associated risk factors and have an unknown source of bacteraemia, but were more likely to have a urinary source. Thirty-day mortality was comparable between those who received empiric piperacillin-tazobactam and a carbapenem (29 [30.9%] vs. 17 [29.8%]), P = 0.89). Those who received empiric piperacillin-tazobactam had a lower 30-day acquisition of multi-drug resistant and fungal infections (7 [7.4%] vs. 14 [24.6%]), Pcarbapenem.

  14. Effect of clavulanic acid on activity of beta-lactam antibiotics in Serratia marcescens isolates producing both a TEM beta-lactamase and a chromosomal cephalosporinase.

    Science.gov (United States)

    Bush, K; Flamm, R K; Ohringer, S; Singer, S B; Summerill, R; Bonner, D P

    1991-01-01

    An isolate of Serratia marcescens that produced both an inducible chromosomal and a plasmid-mediated TEM-1 beta-lactamase was resistant to ampicillin and amoxicillin and also demonstrated decreased susceptibility to extended-spectrum beta-lactam antibiotics (ESBAs). Clavulanic acid did not lower the MICs of the ESBAs, but it decreased the MICs of the penicillins. The TEM-1-producing plasmid was transferred to a more susceptible S. marcescens strain that produced a well-characterized inducible chromosomal beta-lactamase. The MICs of the ESBAs remained at a low level for the transconjugant. Ampicillin and amoxicillin which were good substrates for the plasmid-mediated enzyme, were not well hydrolyzed by the chromosomal enzymes; the ESBAs were hydrolyzed slowly by all the enzymes. When each of the S. marcescens strains was grown with these beta-lactam antibiotics, at least modest increases in chromosomal beta-lactamase activity were observed. When organisms were grown in the presence of clavulanic acid and an ESBA, no enhanced induction was observed. The increases in the MICs of the ESBAs observed for the initial clinical isolate may have been due to a combination of low inducibility, slow hydrolysis, and differences in permeability between the S. marcescens isolates. When clavulanic acid and a penicillin were added to strains that produced both a plasmid-mediated TEM and a chromosomal beta-lactamase, much higher levels of chromosomal beta-lactamase activity were present than were observed in cultures induced by the penicillin alone. This was due to the higher levels of penicillin that were available for induction as a result of inhibition of the TEM enzyme by clavulanate. Images PMID:1803992

  15. Increase in isolation of extended spectrum beta lactamase producing multidrug resistant non typhoidal Salmonellae in Pakistan

    Directory of Open Access Journals (Sweden)

    Khan Erum

    2010-04-01

    Full Text Available Abstract Background Increasing resistance to quinolones and ceftriaxone in non typhoidal Salmonellae is a global concern. Resistance to quinolone and 3rd generation cephalosporin amongst non typhoidal Salmonellae (NTS from Pakistan has been reported in this study. Methods Retrospective analysis of laboratory data was conducted (1990-2006. NTS were isolated and identified from clinical samples using standard microbiological techniques. Antimicrobial susceptibility testing was performed by Kirby Bauer. Extended spectrum beta lactamase production (ESBL was detected using combined disc method. Ciprofloxacin sensitivity was detected by nalidixic acid screening method. Minimum inhibitory concentration (MIC of ciprofloxacin was determined by agar dilution method. Statistical analysis was performed using SPSS version 13. Results Analysis of 1967 NTS isolates showed a significant increase in ciprofloxacin resistance from 23% in 2002 to 50.5% in 2006, with increased mean MIC values from 0.6 to 1.3 ug/mL. Ceftriaxone resistant NTS also increased and ESBL production was seen in 98.7% isolates. These isolates exhibited high resistance against amoxicillin clavulanic acid (57%, gentamicin (69%, amikacin (44% and piperacillin tazobactam (30%. No resistance to carbapenem was seen. Ceftriaxone resistance was significantly higher in children Conclusions Increase in quinolone and ceftriaxone NTS is a serious threat to public health requiring continuous surveillance and use of appropriate screening tests for laboratory detection.

  16. Evaluation of phenotypic tests for detection of Klebsiella pneumoniae carbapenemase and metallo-beta-lactamase in clinical isolates of Escherichia coli and Klebsiella species

    Directory of Open Access Journals (Sweden)

    Kalpana Chauhan

    2015-01-01

    Full Text Available Context: Carbapenemase production is an important mechanism responsible for carbapenem resistance. Aims: Phenotypic detection and differentiation of types of carbapenemase in carbapenem resistant Enterobacteriaceae is important for proper infection control and appropriate patient management. Settings and Design: We planned a study to determine the occurrence of Class A Klebsiella pneumoniae carbapenemase (KPC type and Class B Metallo-β-lactamase (MBL type carbapenemase in hospital and community. Materials and Methods: Clinical isolates of Escherichia coli and Klebsiella species and simultaneously evaluate different phenotypic methods for detection of carbapenemases. Results: It was observed that 20.72% clinical isolates of E. coli and Klebsiella spp. were resistant to carbapenem on screening of which, 14.64% were E. coli and 29.69% were Klebsiella spp. Using phenotypic confirmatory tests the occurrence of carbapenemase production was found to be 87.01% in E. coli and 91.51% in Klebsiella spp. using both modified Hodge test (MHT and combined disk test (CDT using imipenem-ethylenediaminetetraacetic acid. Conclusions: Both MBL and KPC type carbapenemases were seen among clinical isolates of E. coli and Klebsiella spp. CDT is simple, rapid and technically less demanding procedure, which can be used in all clinical laboratories. Supplementing MHT with CDT is reliable phenotypic tests to identify the class A and class B carbapenemase producers.

  17. Molecular cloning and biochemical characterization of VIM-12, a novel hybrid VIM-1/VIM-2 metallo-beta-lactamase from a Klebsiella pneumoniae clinical isolate, reveal atypical substrate specificity.

    Science.gov (United States)

    Kontou, Maria; Pournaras, Spyros; Kristo, Ioulia; Ikonomidis, Alexandros; Maniatis, Antonios N; Stathopoulos, Constantinos

    2007-11-13

    Metallo-beta-lactamases (MBLs) are considered an emerging family of Zn2+-dependent enzymes that significantly contribute to the resistance of many nosocomial pathogens against beta-lactam antimicrobials. Since these plasmid-encoded enzymes constitute specific molecular targets for beta-lactams, their exact mode of action is greatly important in deploying efficient anti-infective treatments and for the control of severe multi-resistant nosocomial infections, which becomes a global problem. A novel hybrid VIM-1/VIM-2-type beta-lactamase (named VIM-12) has recently been identified in a clinical isolate of Klebsiella pneumoniae in Greece. The sequence of this enzyme is highly similar with that of VIM-1 at its N-terminal region and with that of VIM-2 at its C-terminal region, raising the question of whether this sequence similarity reflects also a similar functional role. Moreover, the possible contribution of this novel beta-lactamase to the overall antibiotic resistance of this specific clinical isolate was investigated. The gene encoding VIM-12 was cloned and expressed, and the recombinant enzyme was used for detailed kinetic analysis, using a variety of beta-lactam antibiotics. VIM-12 was found to exhibit narrow substrate specificity, compared to other known beta-lactamases, limited mainly to penicillin and to a much lesser extent to imipenen. Interestingly, meropenem was found to act as a noncompetitive inhibitor of the enzyme, although the active site of VIM-12 exhibited complete conservation of residues among VIM enzymes. We conclude that VIM-12 represents a novel and unique member of the family of known metallo-beta-lactamases, exhibiting atypical substrate specificity.

  18. [Examination of metallo-beta-lactamase-producing different types of Serratia marcescens detected in the same patient].

    Science.gov (United States)

    Takamitsu, Ito; Fukui, Yasuo; Ono, Noriaki; Ikeda, Fumiaki; Kanayama, Akiko; Kobayashi, Intetsu

    2013-03-01

    Metallo-beta-lactamase (MBL) producing Serratia marcescens isolate was recovered from a study patient in September, 2007 in whom MBL non-producing S. marcescens had been isolated 2 months previously. Two S. marcescens isolates recovered from the study patient showed the same pulsed-field gel electrophoresis (PFGE) pattern. Seven S. marcescens isolates were recovered from other patients in our hospital during August, 2007 and November, 2007. Five of the seven isolates produced MBL. All of the MBL-producing isolates showed the same PFGE pattern and harbored plasmids of the same size and bla(IMP) genes. The bla(IMP) genes were easily transferred to Escherichia coli DH5alpha by transformation of a plasmid purified from the MBL-producing isolate. Those transformation experiments suggested that bla(IMP) genes were encoded by the plasmid. From these observations, it was speculated that the MBL non-producing S. marcescens isolate recovered from the study patient had acquired the plasmid which encoded bla(IMP) genes and a monoclone of MBL-producing S. marcescens spread horizontally in our hospital.

  19. Molecular epidemiology of extended-spectrum beta-lactamase (ESBL)-positive Klebsiella pneumoniae from bloodstream infections and risk factors for mortality.

    Science.gov (United States)

    Gürntke, Stephan; Kohler, Christian; Steinmetz, Ivo; Pfeifer, Yvonne; Eller, Christoph; Gastmeier, Petra; Schwab, Frank; Leistner, Rasmus

    2014-12-01

    The prevalence of extended-spectrum beta-lactamase (ESBL)-positive Klebsiella pneumoniae is growing worldwide. Infections with these bacteria are suspected to be related to increased mortality. We aimed to estimate the distribution of ESBL genotypes and to assess the impact on mortality associated with ESBL positivity in cases of bloodstream infection (BSI) due to K. pneumoniae. We performed a cohort study on patients with K. pneumoniae BSI between 2008 and 2011. Presence of ESBL genes was analyzed by PCR and sequencing. Risk factors for mortality were analyzed by Cox-proportional hazard regression. We identified 286 ESBL-negative (81%) and 66 (19%) ESBL-positive cases. 97% (n = 64) of the ESBL-positive isolates were susceptible for meropenem. The most common ESBL genotypes were CTX-M-15 (60%), SHV-5 (27%) and CTX-M-3 (5%). Significant risk factors for mortality were chronic pulmonary disease (HR 1.747) and moderate/severe renal disease (HR 2.572). ESBL positivity was not associated with increased mortality.

  20. Study of antimicrobial resistance due to extended spectrum beta-lactamase-producing Escherichia coli in healthy broilers of Jabalpur

    Science.gov (United States)

    Shrivastav, Arpita; Sharma, R. K.; Sahni, Y. P.; Shrivastav, Neeraj; Gautam, Vidhi; Jain, Sachin

    2016-01-01

    Aim: To study the prevalence of antimicrobial resistance due to extended spectrum beta-lactamase (ESBL)-producing Escherichia coli in samples collected from the ceca of healthy broilers of poultry sale outlets (PSOs) Jabalpur. Materials and Methods: A total of 400 cecal swab samples were taken randomly from freshly slaughtered poultry of 39 PSOs located at four different zones or areas of Jabalpur and were screened for the presence of ESBL-producing E. coli using standard methods. Further they were characterized phenotypically by standard methods. Results: All the 400 samples were screened for E. coli producing ESBL enzyme. Among the samples positive for E. coli 135 were positive for ESBL E. coli giving an overall prevalence of 33.5%. Conclusion: This study related to the prevalence of ESBL-producing E. coli in healthy broilers in Jabalpur is indicative of antibiotic resistance prevalent in the healthy birds which are used for human consumption as well. It also signifies resistance prevalent against beta-lactam antibiotics including third and fourth generations of cephalosporins. PMID:27956778

  1. Detection and characterization of extended-spectrum beta-lactamase (TEM-52)-producing Salmonella serotype Infantis from broilers in Japan.

    Science.gov (United States)

    Shahada, Francis; Chuma, Takehisa; Dahshan, Hesham; Akiba, Masato; Sueyoshi, Masuo; Okamoto, Karoku

    2010-05-01

    During 2004 and 2006, multidrug-resistant Salmonella enterica subspecies enterica serovar Infantis (Salmonella Infantis) isolates (n = 120) were recovered from broiler cecal samples collected from a meat-processing plant, and the isolates were examined. The study was conducted to detect and characterize extended-spectrum beta-lactamase (ESBL)-producing Salmonella Infantis isolates recovered from broiler chickens and determine the mechanisms of transfer of the resistance traits. Extended-spectrum cephalosporins-resistant Salmonella Infantis isolates producing ESBL TEM-52 were detected. The mutant bla(TEM-52) gene and the wild-type bla(TEM-1) gene that mediated resistance to ampicillin (an extended-spectrum penicillin) and cephalothin (a narrow-spectrum cephalosporin) were located on approximately 50-kb conjugative plasmids among beta-lactam-resistant (n = 29) isolates. The bla(TEM) genes did not cotransfer with aadA1, sul1 (both associated with class 1 integrons), tetA, and dfrA5, signifying a chromosomal location of these non-beta-lactam resistance-encoding genes. This is the first report describing TEM-52-producing S. enterica from food-producing animals in Japan. An emergence of TEM-type ESBL is an important concern to public health because this readily transferable resistance mechanism threatens the value of the third-generation cephalosporins and may reduce the clinical utility of this class of antibiotics against pathogenic Gram-negative bacteria.

  2. Identification of Clonal Clusters of Klebsiella pneumoniae Isolates from Chennai by Extended Spectrum Beta Lactamase Genotyping and Antibiotic Resistance Phenotyping Analysis

    Directory of Open Access Journals (Sweden)

    C. Kamatchi

    2009-01-01

    Full Text Available Problem statement: An increased resistance to antibiotics has been reported in Klebsiella pneumoniae, an opportunistic gram negative pathogen belonging to Entrobacteraceae due to the evolution and spread of plasmid encoded extended spectrum beta lactamases and other genes conferring cross-resistance to other antibiotics. This is of concern due to the increasing cost of antibiotic treatment and the spread of multidrug resistance to more pathogenic microorganisms. This study was undertaken to analyze the extent of the problem, to identify the most prevalent MDR isolates of Klebsiella pneumoniae in Chennai and to identify new plant based drugs. Approach: About 188 clinical isolates of Klebsiella pneumoniae were collected from Chennai during the period Nov. 2007-Oct. 2008 and their resistance to different groups of antibiotics were analyzed. These isolates were further characterized by molecular studies to identify the ESBL genes conferring the resistance phenotype. Plant extracts were tested against the MDR isolates to identify new treatment methods. Results: Our results showed that the combination therapy of clavulanic acid with cephalosporins and fluroroquinolones-norfloxacin and ciprofloxacin were the most effective antibiotics for treatment of Klebsiella pneumoniae infections. However resistance to clavulanic acid was increasing among the isolates (17%. All the isolates harbored a plasmid containing one or more of the genes for ESBL resistance. Plasmid isolation from the Isolates followed by ESBL PCR genotyping showed that CTX-M was present in 75 % isolates and TEM in 73% isolates either alone or in combination with the other ESBL genes. SHV ESBL type was present only in 42% of isolates. We identified 4 presumptive clonal spreads which were likely to be prevalent in India by clustering based on ESBL genotypic and antibiotic resistance. The isolates with both SHV and CTX were correlated with the

  3. Very high prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae in bacteriemic patients hospitalized in teaching hospitals in Bamako, Mali

    Science.gov (United States)

    Sangare, Samba Adama; Maiga, Almoustapha Issiaka; Guindo, Ibrehima; Maiga, Aminata; Camara, Namory; Dicko, Oumar Agaly; Dao, Sounkalo; Diallo, Souleymane; Bougoudogo, Flabou; Andremont, Antoine; Maiga, Ibrahim Izetiegouma; Armand-Lefevre, Laurence

    2017-01-01

    The worldwide dissemination of extended-spectrum beta-lactamase producing Enterobacteriaceae, (ESBL-E) and their subset producing carbapenemases (CPE), is alarming. Limited data on the prevalence of such strains in infections from patients from Sub-Saharan Africa are currently available. We determined, here, the prevalence of ESBL-E/CPE in bacteriemic patients in two teaching hospitals from Bamako (Mali), which are at the top of the health care pyramid in the country. During one year, all Enterobacteriaceae isolated from bloodstream infections (E-BSI), were collected from patients hospitalized at the Point G University Teaching Hospital and the pediatric units of Gabriel Touré University Teaching Hospital. Antibiotic susceptibility testing, enzyme characterization and strain relatedness were determined. A total of 77 patients had an E-BSI and as many as 48 (62.3%) were infected with an ESBL-E. ESBL-E BSI were associated with a previous hospitalization (OR 3.97 95% IC [1.32; 13.21]) and were more frequent in hospital-acquired episodes (OR 3.66 95% IC [1.07; 13.38]). Among the 82 isolated Enterobacteriaceae, 58.5% were ESBL-E (20/31 Escherichia coli, 20/26 Klebsiella pneumoniae and 8/15 Enterobacter cloacae). The remaining (5 Salmonella Enteritidis, 3 Morganella morganii 1 Proteus mirabilis and 1 Leclercia adecarboxylata) were ESBL negative. CTX-M-1 group enzymes were highly prevalent (89.6%) among ESBLs; the remaining ones being SHV. One E. coli produced an OXA-181 carbapenemase, which is the first CPE described in Mali. The analysis of ESBL-E relatedness suggested a high rate of cross transmission between patients. In conclusion, even if CPE are still rare for the moment, the high rate of ESBL-BSI and frequent cross transmission probably impose a high medical and economic burden to Malian hospitals. PMID:28245252

  4. Sequential necrotizing fasciitis caused by the monomicrobial pathogens Streptococcus equisimilis and extended-spectrum beta-lactamase-producing Escherichia coli.

    Science.gov (United States)

    Endo, Akiko; Matsuoka, Ryosuke; Mizuno, Yasushi; Doi, Asako; Nishioka, Hiroaki

    2016-08-01

    Necrotizing fasciitis is a rapidly progressing bacterial infection of the superficial fascia and subcutaneous tissue that is associated with a high mortality rate and is caused by a single species of bacteria or polymicrobial organisms. Escherichia coli is rarely isolated from patients with monomicrobial disease. Further, there are few reports of extended-spectrum beta-lactamase (ESBL)-producing E. coli associated with necrotizing fasciitis. We report here our treatment of an 85-year-old man who was admitted because of necrotizing fasciitis of his right thigh. Streptococcus equisimilis was detected as a monomicrobial pathogen, and the infection was cured by amputation of the patient's right leg and the administration of antibiotics. However, 5 days after discontinuing antibiotic therapy, he developed necrotizing fasciitis on his right upper limb and died. ESBL-producing E. coli was the only bacterial species isolated from blood and skin cultures. This case demonstrates that ESBL-producing E. coli can cause monomicrobial necrotizing fasciitis, particularly during hospitalization and that a different bacterial species can cause disease shortly after a previous episode.

  5. Comparison between phenotypic and PCR for detection of OXA-23 type and metallo-beta-lactamases producer Acinetobacter spp.

    Directory of Open Access Journals (Sweden)

    Azimi, Leila

    2013-11-01

    Full Text Available [english] Background: Resistance to carbapenems is developing around the world and can cause many problems for treatment of patients. Production of metallo-beta-lactamase (MBL is one of the main mechanism for this type of resistance. So, detection of MBL-producer microorganisms can prevent the spread of this type of resistance.Materials and methods: In this study 94 spp. were investigated. Resistance to imipenem was conducted after purification and identification. Combination disc (CD and Double Disc Synergy Test (DDST were performed for phenotypic detection of MBL and the molecular PCR method was done for vim-1, vim-2, imp-1 and OXA-23 genes.Results: According to TSI, SIM and oxidation-fermentation (OF test and PCR assay 93 and one strain were identified. 85% of them were resistant to imipenem. 34% of them have a positive combination disc test (CD while Double Disc Synergy Test (DDST was negative for all of them. The vim-1, vim-2 and imp-1 genes were not detected in PCR molecular method, however in 74% of strains with positive results in combination disc, were positive for the OXA-23 gene after PCR test. This study shows that the blaOXA-23 resistance determinant may become an emerging therapeutic problem.Discussion: According to the results, it seems that combination disc does not have enough specificity for detection of MBL-producer and using Double Disc Synergy Test (DDST can be more convenient.

  6. Successive emergence of extended-spectrum beta-lactamase-producing and carbapenemase-producing Enterobacter aerogenes isolates in a university hospital.

    Science.gov (United States)

    Biendo, M; Canarelli, B; Thomas, D; Rousseau, F; Hamdad, F; Adjide, C; Laurans, G; Eb, F

    2008-03-01

    Sixty-two clinical isolates of Enterobacter aerogenes resistant to expanded-spectrum cephalosporins were collected between July 2003 and May 2005. Among these isolates, 23 (37.1%) were imipenem (IPM) susceptible, and 39 (62.9%) were IPM insusceptible, of which 89.7% (35/39) were resistant and 10.3% (4/39) were intermediate. Isolate genotypes were compared by pulsed-field gel electrophoresis. Of 62 isolates, 48 belonged to epidemic pulsotype A (77.4%). This pulsotype included 37.5% and 58.4% of beta-lactam phenotypes b and a, respectively. Nine isolates (14.5%) belonged to pulsotype E, which included 22.3% and 77.7% of phenotypes b and a, respectively. The beta-lactamases with pIs of 5.4, 6.5, 8.2, and 8.2 corresponded to extended-spectrum beta-lactamases (ESBLs) TEM-20, TEM-24, SHV-5, and SHV-12, respectively. Of 39 IPM-insusceptible E. aerogenes isolates, 26 (66.6%) were determined to be metallo-beta-lactamase producers, by using a phenotypic method. Of these isolates, 24 harbored a bla(IMP-1) gene encoding a protein with a pI of >9.5, and two carried the bla(VIM-2) gene encoding a protein with a pI of 5.3, corresponding to beta-lactamases IMP-1 and VIM-2, respectively. The remaining 13 (33.4%) isolates were negative for the bla(IMP-1) and bla(VIM-2) genes but showed an alteration of their outer membrane proteins (OMPs). Ten of these isolates produced the two possible OMPs (32 and 42 kDa), with IPM MICs between 8 and 32 microg/ml, and three others produced only a 32-kDa OMP with IPM MICs >32 microg/ml. This work demonstrates that, in addition to resistance to expanded-spectrum cephalosporins, IPM resistance can occur in ESBL-producing E. aerogenes isolates by carbapenemase production or by the loss of porin in the outer membrane.

  7. Prevalência de sepse por bactérias Gram negativas produtoras de beta-lactamase de espectro estendido em Unidade de Cuidados Intensivos Neonatal Prevalence of extended-spectrum beta-lactamase producing Gram-negative bacterial sepsis in a Neonatal Intensive Care Unit

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    Carla Regina Tragante

    2008-03-01

    Full Text Available OBJETIVO: Determinar a prevalência e a mortalidade de sepse neonatal por bactérias Gram negativas produtoras de beta-lactamase de espectro estendido (ESBL em Unidade de Cuidados Intensivos Neonatal. MÉTODOS: Trata-se de um estudo retrospectivo e descritivo de 236 recém-nascidos com suspeita de sepse entre 2000 e 2004. O diagnóstico de sepse foi confirmado pela presença de sinais clínicos associada à positividade da hemocultura. A triagem para bactérias ESBL foi realizada segundo os critérios do National Committee for Clinical Laboratory Standards. RESULTADOS: 84 (36% recém-nascidos apresentaram hemocultura positiva, sendo a Klebsiella pneumoniae o agente mais prevalente (47%. A análise dos neonatos com infecção por Klebsiella pneumoniae mostrou que sete destas eram ESBL, perfazendo uma taxa de infecção de 0,4%. Todos os recém-nascidos com Klebsiella pneumoniae ESBL - exceto um - foram hospitalizados por mais de 21 dias e necessitaram de ventilação mecânica; todos tinham cateter central, nutrição parenteral e antibióticos de largo espectro. A mortalidade ocorreu em 36 (43% dos 84 neonatos com sepse confirmada. Dentre os óbitos, as hemoculturas mostraram Gram negativos (67% e fungos (19%. Em relação à Klebsiella pneumoniae ESBL, três recém-nascidos (43% morreram. CONCLUSÕES: A prevalência de sepse por Klebsiella pneumoniae ESBL no período do estudo foi de 0,4% e a mortalidade de 43%. É importante a detecção e o controle da disseminação deste tipo de microrganismo por seu impacto negativo na sobrevida de recém-nascidos prematuros e/ou doentes.OBJECTIVE: To determine the neonatal sepsis prevalence and the mortality of extended-spectrum beta-lactamase producing Gram-negative bacteria (ESBL in a Neonatal Intensive Care Unit. METHODS: This is a descriptive and retrospective study of 236 newborn infants with sepsis suspicion from 2000 to 2004. The diagnosis was confirmed by clinical signs and positive blood culture

  8. Beta-lactamases of Mycobacterium tuberculosis and Mycobacterium kansasii.

    Science.gov (United States)

    Segura, C; Salvadó, M

    1997-09-01

    Re-emergence of infectious diseases caused by mycobacteria as well as the emergence of multiresistant strains of Mycobacterium has promoted the research on the use of beta-lactames in the treatment of such diseases. Mycobacteria produce beta-lactamases: M. tuberculosis produces a wide-spectrum beta-lactamase whose behaviour mimicks those of Gram-negative bacteria. M. kansasii produces also beta-lactamase which can be inhibited by clavulanic acid. An overview on beta-lactamases from both species is reported.

  9. [THE APPLICATION OF SELECTIVE CHROMOGENIC AGAR FOR DETECTING ENTEROBACTERIA WITH PRODUCTION OF BETA-LACTAMASES].

    Science.gov (United States)

    Korobova, A G; Frolova, L N; Kliasova, G A

    2015-11-01

    The detection of enterobacteria with production of beta-lactamases of extended spectrum in selective chromogenic agar was analyzed The results ofdetection of beta-lactamases of extended spectrum was compared with "double disc" technique. The smears from mucous membrane of guttur and rectum from patients were analyzed in parallel on solid growth agar (Endo or Mac Conkey) and on selective agar CHROMagartm ESBL (CHROMagar France). The production of beta-lactamases of extended spectrum was confirmed using "double discs" technique. To exclude hyper-production of ampC beta-lactamases E-test was applied containing cefotetan and cefotetan with cloxacillin. The sampling consisted of 1552 samples from patients. The study permitted to isolate 1243 strains of enterobacteria on agar Endo or Mac Conkey and 409 strains of enterobacteria on selective agar CHROMagartm ESBL (Escherichia coli n = 226, Klebsiella pneumoniae n = 105, enterobacter spp. n = 35, Citrobacter spp. n = 21, others n = 22). The application of "double discs" technique confirmed production of beta-lactamases of extended spectrum in 386 (94%) out of 409 strains isolated on agar CHROMagartm ESBL. In 23 (6%) of strains no confirmation was established and hyper-production of ampC of beta-lactamases was established 15 out of total. Additionally, 8 were sensitive to cephalosporin of third generation. All enterobacteria isolated on agar Endo or Mac Conkey also were tested by "double discs" technique. Overall, 394 strains of enterobacteria with production of beta-lactamases of extended spectrum were obtained. On all agars (agar Endo or Mac Conkey and CHROMagartm ESBL)--263 (67%) strains; only on CHROMagartm ESBL--123 (31%) and only on agar Endo or Mac Conkey--8 (2%) (p agar CHROMagartm ESBL made up to 98% and specificity--97%. The resolution about detection of enterobacteria producing beta-lactamases of extended spectrum were submitted to clinic in 18-24 hours after arrival ofsamplesfrom patients in laboratory. The CHR

  10. Molecular characterization of the extended-spectrum beta-lactamase (ESBL)-producing Shigella spp. in Shanghai.

    Science.gov (United States)

    Li, J; Li, B; Ni, Y; Sun, J

    2015-03-01

    Shigellosis is a public health concern in China. We tested 216 Shigella isolates collected in Shanghai in 2007 for the production of extended-spectrum beta-lactamases (ESBLs). ESBL-producing isolates were characterized using polymerase chain reaction (PCR)-based genotyping, conjugation, pulsed-field gel electrophoresis (PFGE), and DNA sequence analysis of regions adjacent to bla genes. Plasmids containing genes encoding ESBLs were analyzed using plasmid replicon typing. ESBLs were produced by 18.1 % (39/216) of Shigella isolates, and all 39 ESBL-producing strains harbored bla CTX-M genes. CTX-M-14 was the most frequent variant (69.2 %, 27/39), followed by CTX-M-15 (15.4 %, 6/39). All bla CTX-M genes were transferable by conjugation, and the insertion sequence ISEcp1 was detected upstream of all bla CTX-M genes. The CTX-M-producing Shigella isolates showed high clonal diversity. IncI1, IncFII, IncN, and IncB/O replicons were respectively detected in 23 (58.9 %), 9 (23.1 %), 1 (2.6 %), and 1 (2.6 %) of the 39 transconjugants carrying bla CTX-M. The bla CTX-M-14 genes were most frequently carried by IncI1 (n = 13, 48.1 %) or IncFII (n = 9, 33.3 %) plasmids, and the bla CTX-M-15 genes were closely associated with IncI1 (n = 5, 83.3 %). Our findings demonstrate the high prevalence of ESBL-producing Shigella in Shanghai, the importance of plasmids and ISEcp1 as carriers of bla CTX-M genes, and the close association between certain bla CTX-M genes with a specific plasmid.

  11. Increased detection of extended spectrum beta-lactamase producing Salmonella enterica and Escherichia coli isolates from poultry

    NARCIS (Netherlands)

    Dierikx, C.M.; Essen-Zandbergen, van A.; Veldman, K.T.; Smith, H.E.; Mevius, D.J.

    2010-01-01

    To gain more information on the genetic basis of the rapid increase in the number of isolates exhibiting non-wild type Minimum Inhibitory Concentrations (MICs) for cefotaxime observed since 2003, beta-lactamase genes of 22 Salmonella enterica and 22 Escherichia coli isolates from broilers in 2006 sh

  12. Meta-analysis of proportion estimates of Extended-Spectrum-Beta-Lactamase-producing Enterobacteriaceae in East Africa hospitals

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    Tolbert Sonda

    2016-05-01

    Full Text Available Abstract Background A high proportion of Extended-Spectrum-Beta-Lactamase (ESBL producing Enterobacteriaceae is causing common infections in all regions of the world. The burden of antibiotic resistance due to ESBL in East Africa is large but information is scarce and thus it is unclear how big the problem really is. To gain insight into the magnitude and molecular epidemiology of ESBL-producing Enterobacteriaceae in East Africa a literature search was performed in PubMed on 31 July 2015 to retrieve articles with relevant information on ESBL. Methods and results Meta-analysis was performed to determine overall proportion estimate of ESBL-producing Enterobacteriaceae. A total of 4076 bacterial isolates were included in the analysis. The overall pooled proportion of ESBL-producing Enterobacteriaceae among included surveys done in East African hospitals was found to be 0.42 (95 % CI: 0.34–0.50. Heterogeneity (I2 between countries’ proportions in ESBL was significantly high (96.95 % and p < 0.001. The frequently detected genes encoding ESBL were CTX-M, TEM, SHV and OXA while the most infrequent reported genes were KPC and NDM. Conclusion The available studies show a very wide variation in resistance due to ESBL between countries. This highlights a need for active surveillance systems which can help understand the actual epidemiology of ESBL, aid in formulating national or regional guidelines for proper screening of ESBL, and support developing standardized approaches for managing patients colonized with ESBL.

  13. Extended-spectrum beta-lactamases in Klebsiella spp and Escherichia coli obtained in a Brazilian teaching hospital: detection, prevalence and molecular typing beta-lactamases de espectro ampliado em Klebsiella spp e em Escherichia coli obtidas em um hospital escola brasileiro: detecção, prevalência e tipagem molecular

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    Ana Lúcia Peixoto de Freitas

    2003-12-01

    Full Text Available His study was performed to compare the methods of detection and to estimate the prevalence of extended-spectrum beta-lactamases (ESBL among Klebsiella spp and E.coli in a university hospital in southern Brazil. We also used a molecular typing method to evaluate the genetic correlation between isolates of ESBL K.pneumoniae. Production of ESBL was investigated in 95 clinical isolates of Klebsiella spp and Escherichia coli from Hospital de Clínicas de Porto Alegre, using Kirby-Bauer zone diameter (KB, double-disk diffusion (DD, breakpoint for ceftazidime (MIC CAZ, increased zone diameter with clavulanate (CAZ/CAC and ratio of ceftazidime MIC/ceftazidime-clavulanate MIC (MIC CAZ/CAC. Molecular typing was performed by DNA macrorestriction analysis followed by pulsed-field gel electrophoresis. The KB method displayed the highest rates of ESBL (up to 70% of Klebsiella and 59% of E.coli, contrasting with all the other methods (p Este estudo foi desenvolvido para comparar métodos de detecção e para estimar a prevalência de Klebsiella spp e E.coli produtoras de beta-lactamases de espetro ampliado (ESBL em um Hospital Universitário no sul do Brasil. A correlação genética, determinada através de método molecular de tipagem, entre as amostras de K. pneumoniae também foi determinada. A produção de ESBL foi investigada em 95 amostras de Klebsiella spp e E.coli obtidas de pacientes no Hospital de Clínicas de Porto Alegre usando-se: medida do diâmetro a zona de inibição (KB, dupla-difusão de disco (DD, valores de concentração inibitória mínima da ceftazidima (MIC CAZ, aumento do diâmetro da zona de inibição com adição de clavulanato (CAZ/CAC e a relação entre o MIC da ceftazidima/MIC ceftazidima com clavulanato (MIC CAZ/CAC. A tipagem molecular foi realizada utilizando-se o método de macrorestrição de DNA e eletroforese em campo pulsado (PFGE. O método KB apresentou as maiores taxas de produção de ESBL (> 70% para Klebsiella e

  14. First report of KPC-producing Klebsiella pneumoniae in Croatia.

    Science.gov (United States)

    Bedenić, Branka; Mazzariol, Annarita; Plečko, Vanda; Bošnjak, Zrinka; Barl, Petra; Vraneš, Jasmina; Cornaglia, Giuseppe

    2012-08-01

    In February 2011, a 78-year-old male patient was admitted to Clinical Hospital Center Zagreb with subdural haematoma. Klebsiella pneumoniae with reduced susceptibility to carbapenems was isolated. PCR revealed the presence of bla(KPC), bla(TEM), and bla(SHV) genes. Sequencing of bla(KPC) gene identified K. pneumoniae carbapenemase (KPC)-2 beta-lactamase. The strain belonged to ST37 clone by multilocus sequence typing. Infection control efforts limited the spread of KPC-producing clone of K. pneumoniae in our hospital so far. To our knowledge, this is the first report of a KPC-producing K. pneumoniae in Croatia.

  15. High prevalence of extensively drug-resistant and metallo beta-lactamase-producing clinical Acinetobacter baumannii in Iran.

    Science.gov (United States)

    Maspi, Hossein; Mahmoodzadeh Hosseini, Hamideh; Amin, Mohsen; Imani Fooladi, Abbas Ali

    2016-09-01

    Acinetobacter species particularly Acinetobacter baumannii (A. baumannii) have been widely reported as broad-spectrum antibiotic resistant pathogens. Expression of various types of metallo beta-lactamases (MBL), classified as Ambler class B, has been associated with carbapenem resistance. Here, we attempted to assess the frequency of extensively drug-resistant (XDR) and MBL-producing A. baumannii among clinical isolates. 86 clinical A. baumannii strains were collected from 2014 to 2015 and their susceptibility to meropenem (10 μg), imipenem (10 μg), azteronem (30 μg), pipracillin (100 μg) tazobactam (110 μg), tobramycin (10 μg), fosfomycin (200 μg), rifampicin (5 μg), colistin (10 μg), tigecycline (15 μg), sulbactam/ampicillin (10 μg + 10 μg) and polymixin B (300 U) was evaluated using disk diffusion method. The MBL-producing isolates were screened using combined disc diffusion method. Furthermore, the presence of blaVIM, blaIMP, blaSPM, blaGIM, blaSIM and blaNDM was detected by PCR. 34.9% of isolates were recovered from bronchoalveolar lavage (BAL). 81 (94.2%) and 62 (71.2%) isolates were multidrug resistance (MDR) and XDR, respectively. 44 (51.2%) and 65 (75.6%) isolates were MBL-producing strains with resistance to imipenem and meropenem, respectively. 2 (2.3%), 13 (15.1%), 2 (2.3%), 4 (4.7%) and 2 (2.3%) isolates carried blaVIM, blaIMP, blaSPM, blaGIM and blaSIM genes, respectively. Our data showed that the rate of XDR and MBL A. baumannii is on the rise.

  16. Extended-spectrum beta-lactamase-producing bacteria isolated from hematologic patients in Manaus, State of Amazonas, Brazil

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    Cristina Motta Ferreira

    2011-09-01

    Full Text Available Antibiotic therapy in hematologic patients, often weak and susceptible to a wide range of infections, particularly nosocomial infections derived from long hospitalization periods, is a challenging issue. This paper presents ESBL-producing strains isolated from such hematologic patients treated at the Amazon Hematology and Hemotherapy Foundation (HEMOAM in the Brazilian Amazon Region to identify the ESBL genes carried by them as well as the susceptibility to 11 antimicrobial agents using the E-test method. A total of 146 clinical samples were obtained from July 2007 to August 2008, when 17 gram-negative strains were isolated in our institution. The most frequent isolates confirmed by biochemical tests and 16S rRNA sequencing were E. coli (8/17, Serratia spp. (3/17 and B.cepacia (2/17. All gram-negative strains were tested for extended-spectrum-beta-lactamases (ESBLs, where: (12/17 strains carried ESBL; among these, (8/12 isolates carried blaTEM, blaCTX-M, blaOXA, blaSHV genes, (1/12 blaTEM gene and (3/12 blaTEM, blaCTX-M, blaOXA genes. Antibiotic resistance was found in (15/17 of the isolates for tetracycline, (12/17 for ciprofloxacin, (1/17 resistance for cefoxitin and chloramphenicol, (1/17 for amikacin and (3/17 cefepime. This research showed the presence of gram-negative ESBL-producing bacteria infecting hematologic patients in HEMOAM. These strains carried the blaTEM, blaSHV, blaCTX-M and blaOXA genes and were resistant to different antibiotics used in the treatment. This finding was based on a period of 13 months, during which clinical samples from specific populations were obtained. Therefore, caution is required when generalizing the results that must be based on posological orientations and new breakpoints for disk diffusion and microdilution published by CLSI 2010.

  17. Extended-spectrum beta-lactamases producing E. coli in wildlife, yet another form of environmental pollution?

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    Sebastian eGuenther

    2011-12-01

    Full Text Available Wildlife is normally not exposed to antimicrobial agents but can acquire antimicrobial resistant bacteria through contact with humans, domesticated animals and the environment, where water polluted with faeces seems to be the most important vector. E. coli, a ubiquitous commensal bacterial species colonizing the intestinal tract of mammals and birds, is also found in the environment. Extended-spectrum beta-lactamases producing E. coli (ESBL-E. coli represent a major problem in human and veterinary medicine, particular in nosocomial infections. Additionally an onset of community acquired ESBL-E. coli infections and an emergence in livestock farming has been observed in recent years, suggesting a successful transmission as well as persistence of ESBL-E. coli strains outside clinical settings. Another parallel worldwide phenomenon is the spread of ESBL-E. coli into the environment beyond human and domesticated animal populations, and this seems to be directly influenced by antibiotic practice. This might be a collateral consequence of the community onset of ESBL-E. coli infections but can result (a in a subsequent colonization of wild animal populations which can turn into an infectious source or even a reservoir of ESBL-E.coli, (b in a contribution of wildlife to the spread and transmission of ESBL-E. coli into fragile environmental niches, (c in new putative infection cycles between wildlife, domesticated animals and humans, and (d in problems in the medical treatment of wildlife. This review aims to summarize the current knowledge on ESBL-E. coli in wildlife, in turn underlining the need for more large scale investigations, in particular sentinel studies to monitor the impact of multiresistant bacteria on wildlife.

  18. Extended-Spectrum Beta-Lactamases Producing E. coli in Wildlife, yet Another Form of Environmental Pollution?

    Science.gov (United States)

    Guenther, Sebastian; Ewers, Christa; Wieler, Lothar H.

    2011-01-01

    Wildlife is normally not exposed to clinically used antimicrobial agents but can acquire antimicrobial resistant bacteria through contact with humans, domesticated animals and the environment, where water polluted with feces seems to be the most important vector. Escherichia coli, an ubiquitous commensal bacterial species colonizing the intestinal tract of mammals and birds, is also found in the environment. Extended-spectrum beta-lactamases producing E. coli (ESBL-E. coli) represent a major problem in human and veterinary medicine, particular in nosocomial infections. Additionally an onset of community-acquired ESBL-E. coli infections and an emergence in livestock farming has been observed in recent years, suggesting a successful transmission as well as persistence of ESBL-E. coli strains outside clinical settings. Another parallel worldwide phenomenon is the spread of ESBL-E. coli into the environment beyond human and domesticated animal populations, and this seems to be directly influenced by antibiotic practice. This might be a collateral consequence of the community-onset of ESBL-E. coli infections but can result (a) in a subsequent colonization of wild animal populations which can turn into an infectious source or even a reservoir of ESBL-E. coli, (b) in a contribution of wildlife to the spread and transmission of ESBL-E. coli into fragile environmental niches, (c) in new putative infection cycles between wildlife, domesticated animals and humans, and (d) in problems in the medical treatment of wildlife. This review aims to summarize the current knowledge on ESBL-E. coli in wildlife, in turn underlining the need for more large scale investigations, in particular sentinel studies to monitor the impact of multiresistant bacteria on wildlife. PMID:22203818

  19. Prevalence and characterization of extended-spectrum beta-lactamase (ESBL)- and CMY-2-producing Escherichia coli isolates from healthy food-producing animals in Tunisia.

    Science.gov (United States)

    Ben Sallem, Rym; Ben Slama, Karim; Sáenz, Yolanda; Rojo-Bezares, Beatriz; Estepa, Vanesa; Jouini, Ahlem; Gharsa, Haythem; Klibi, Naouel; Boudabous, Abdellatif; Torres, Carmen

    2012-12-01

    The prevalence of extended-spectrum beta-lactamase (ESBL)- and plasmidic AmpC-beta-lactamase (pAmpC-BL)-producing Escherichia coli isolates has been studied in food-producing animals at the farm level in Tunisia, and recovered isolates were characterized for the presence of other resistance genes and integrons. Eighty fecal samples of food-producing animals (23 sheep, 22 chickens, 22 cattle, six horses, five rabbits, and two dromedaries) were obtained from 35 different farms in Tunisia in 2011. Samples were inoculated onto MacConkey agar plates supplemented with cefotaxime (2 mg/L) for cefotaxime-resistant (CTX(R)) E. coli recovery. CTX(R) E. coli isolates were detected in 11 out of 80 samples (13.8%), and one isolate per sample was further characterized (10 from chickens and one from a dromedary). The 11 CTX(R) isolates were distributed into phylogroups: B1 (five isolates), A (two isolates), D (three isolates), and B2 (one isolate). The following beta-lactamase genes were detected: bla(CTX-M-1) (seven isolates), bla(CTX-M-1)+bla(TEM-135) (one isolate), bla(CTX-M-1)+bla(TEM-1b) (one isolate), and bla(CMY-2) (two isolates). All ESBL- and pAmpC-BL-producing E. coli strains showed unrelated pulsed-field gel electrophoresis patterns. Seven isolates contained class 1 integrons with four gene cassette arrangements: dfrA17-aadA5 (three isolates), dfrA1-aadA1 (two isolates), dfrA15-aadA1 (one isolate), and aadA1 (one isolate). All isolates showed tetracycline resistance and contained the tet(A) +/- tet(B) genes. Virulence genes detected were as follows (number of isolates in parentheses): fimA (10); aer (eight); papC (two); and papGIII, hly, cnf, and bfp (none). Chicken farms constitute a reservoir of ESBL- and pAmpC-BL-producing E. coli isolates of the CTX-M-1 and CMY-2 types that potentially could be transmitted to humans via the food chain or by direct contact.

  20. Molecular characterization and clinical significance of New Delhi metallo-beta-lactamases-1 producing Escherichia coli recovered from a South Indian tertiary care hospital

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    Arindam Ckakraborty

    2015-01-01

    Full Text Available Context: The increased rate of infection by New Delhi metallo-beta-lactamases-1 (NDM1 producing Escherichia coli is a major concern since they show a high rate of drug resistance and are responsible for mortality and morbidity. Aims: To characterize the NDM1 producing E. coli isolates and their impact on patients′ clinical outcome. Settings and Design: This descriptive study was carried out in a multi-specialty tertiary care hospital. Materials and Methods: Three hundred nonrepeat strains of E. coli from inpatients were included in the study. Modified Hodge test and metallo-beta-lactamases (MBL e-test were performed to detect carbapenemase and MBL activity. Polymerase chain reaction (PCR technique was performed to detect NDM1. NDM1 positive isolates were further tested for plasmid mediated AmpC, blaCTX , blaSHV , blaTEM genes and also for phylogrouping by PCR methods. Treatment and patients′ clinical outcome were also analyzed. Results: Out of 300 isolates, 21 (7% were MBL producers by phenotypic methods. Of this, 17 (81% were NDM1 positives, among the NDM1 producers 6 (35% isolates were belongs to phylogroups D followed by A 5 (29%, B1 4 (24% and B2 2 (12%, 15 (88% isolates were blaCTX-M positive suggestive of extended-spectrum beta lactamase producing strain and 7 (47% were positive with CIT type of AmpC. With the follow-up of the patients, it was found that 12 (71% recovered and 3 (18% developed relapses, and mortality was seen in 2 (12% patients. Conclusions: NDM1 producing isolates showed a high degree of drug resistance but can be treated with suitable antimicrobials, in the majority. Early detection and choice of appropriate antibiotics may help in reducing mortality and morbidity.

  1. blaCTX-M-I group extended spectrum beta lactamase-producing Salmonella typhi from hospitalized patients in Lagos, Nigeria

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    Akinyemi KO

    2015-05-01

    Full Text Available Kabiru O Akinyemi,1 Bamidele A Iwalokun,2 Olajide O Alafe,1 Sulaiman A Mudashiru,1 Christopher Fakorede,11Department of Microbiology, Lagos State University, Ojo, Lagos, Nigeria; 2Biochemistry and Nutrition Division, Nigerian Institute of Medical Research, Yaba, Lagos, NigeriaPurpose: The global spread of blaCTX-M-I extended-spectrum beta-lactamase (ESBL-producing Salmonella spp. remains a major threat to treatment and control. Evidence of emergence and spread of this marker are lacking in Nigeria. This study investigated blaCTX-M-I ESBL production among Salmonella isolates from hospitalized patients.Methods: Patients (158 total made up of two groups were evaluated. Group A was composed of 135 patients with persistent pyrexia and group B was composed of 23 gastroenteritis patients and their stool samples. Samples were cultured, and isolates were identified and were subjected to antibiotic susceptibility testing by standard methods. Isolates were further screened for ESBL production, blaCTX-M-I genes and transferability by double disk synergy test, plasmid extraction, polymerase chain reaction, and conjugation experiment.Results: Thirty-five (25.9% Salmonella isolates were identified from group A, of which 74.3% were S. typhi, 22.9% were S. paratyphi and two (5.7% were invasive non-typhoidal S. enteritidis. Nine Plasmodium falciparum infections were recorded, four of which were identified as co-infections with typhoidal Salmonella. Only two (8.7% S. enteritidis samples were obtained from group B (P>0.05. A total of 24 isolates were ESBL-positive, eliciting resistance to five to seven antibiotics, and were multiple-drug resistant. ESBL production due to the blaCTX-M-I gene cluster was detected in eleven (45.8% Salmonella isolates. Nine (81.8% of the eleven blaCTX-M-I ESBL producers were S. typhi and two (18.2% isolates were S. enteritidis. Four of nine S. typhi blaCTX-M-I ESBL-producing strains harbored 23 kb self-transmissible plasmid that was co

  2. Distribution and Antimicrobial Susceptibility Pattern of Gram Negative Bacteria Causing Urinary Tract Infection (UTI and Detection New Delhi Metallo-beta-lactamase-1 (NDM-1 Producing Isolates in Ahwaz

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    Parviz Afrugh

    2016-04-01

    Full Text Available Background: Urinary tract infection (UTI is the commonest bacterial infectious disease in worldwide (especially in developing countries with a high rate of morbidity and financial cost. The management of UTI infections has been jeopardized by increase in immergence of antimicrobial drug resistance. Knowledge of the local bacterial etiology and susceptibility patterns is required to trace any change that might have occurred in time so that updated recommendation for optimal empirical therapy of UTI can be made. The aim of this investigation was distribution and antimicrobial susceptibility pattern of gram negative bacteria causing urinary tract infection (UTI and detection NDM-1 (new-delhi-metallo-beta-lactamase-1 producing isolates in Ahwaz. Materials and Methods: This cross-sectional study was done during a period of one year from April 2013 to March 2014. Clean catch midstream urine samples were collected from suspected patients to UTI. The isolates were identified based on morphological and biochemical testes. Culture was performed on routine microbiological media. Susceptibility testing was performed according CLSI (2013 guidelines. Detection of carbapenemase producing isolates was performed by modified hodge test (MHT. Metallo-beta-lactamase isolates were detected by imipenem-EDTA combined disc test (CDT. Results: In this study 708 gram negative organisms were isolated from urine samples. E.coli was the most common isolated bacteria (67% followed by Klebsiella spp. (26.5% and Enterobacter spp. (2.5%. In antibiotic susceptibility testing more than 90% of isolates were sensitive to tetracycline, ceftazidime, meropenem, amikacin, cefotaxime, imipenem, and cefepime. Isolates were more resistant to cephalothin (32%, co-trimoxazol (30.5%, and nalidixic acid (25%. Conclusion: In our results isolated organisms from outpatients showed very high sensitivity to common antibiotics. Continuous and regular monitoring of susceptibility pattern of

  3. Emergence of quinolone resistance among extended-spectrum beta-lactamase-producing Enterobacteriaceae in the Central African Republic: genetic characterization

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    Frank Thierry

    2011-08-01

    Full Text Available Abstract Background Cross-resistance to quinolones and beta-lactams is frequent in Enterobacteriaceae, due to the wide use of these antibiotics clinically and in the food industry. Prescription of one of these categories of antibiotic may consequently select for bacteria resistant to both categories. Genetic mechanisms of resistance may be secondary to a chromosomal mutation located in quinolone resistance determining region of DNA gyrase or topoisomerase IV or to a plasmid acquisition. The insertion sequence ISCR1 is often associated with qnr and may favour its dissemination in Gram-negative bacteria. The aim of this study was to determine the genetic mechanism of quinolone resistance among extended-spectrum beta-lactamase-producing Enterobacteriaceae strains in the Central African Republic. Findings Among seventeen ESBL-producing Enterobacteriaceae isolated from urine, pus or stool between January 2003 and October 2005 in the Central African Republic, nine were resistant to ciprofloxacin (seven from community patients and two from hospitalized patients. The ESBL were previously characterized as CTX-M-15 and SHV-12. Susceptibility to nalidixic acid, norfloxacin and ciprofloxacin, and the minimal inhibitory concentrations of these drugs were determined by disc diffusion and agar dilution methods, respectively. The presence of plasmid-borne ISCR1-qnrA region was determined by PCR and amplicons, if any, were sent for sequencing. Quinolone resistance determining region of DNA gyrase gyrA gene was amplified by PCR and then sequenced for mutation characterization. We found that all CTX-M-producing strains were resistant to the tested quinolones. All the isolates had the same nucleotide mutation at codon 83 of gyrA. Two Escherichia coli strains with the highest MICs were shown to harbour an ISCR1-qnrA1 sequence. This genetic association might favour dissemination of resistance to quinolone and perhaps other antibiotics among Enterobacteriaceae

  4. Fecal Colonization with Extended-Spectrum Beta-Lactamase and AmpC-Producing Escherichia coli

    Directory of Open Access Journals (Sweden)

    Mohamed H. Al-Agamy

    2016-01-01

    Full Text Available Background. Extended-spectrum β-lactamases (ESβLs and AmpC β-lactamases cause β-lactam resistance in Escherichia coli. Fecal colonization by ESβL- and/or AmpC-positive E. coli is a source of nosocomial infections. Methods. In order to investigate inpatient fecal colonization by ESβLs and AmpC, antibiotic sensitivity tests were conducted and minimum inhibitory concentrations (MICs were determined using the disk diffusion method and E-test, respectively. Characterization of ESβL and AmpC was performed using E-test strips, and a set of PCRs and DNA sequence analyses were used to characterize the ESβL and AmpC genes. Results. The whole collection of E. coli isolates (n=50 was sensitive to imipenem, tigecycline, colistin, and fosfomycin, while 26% of the isolates showed reduced susceptibility to ceftazidime (MIC ≥ 4 μg/mL. ESβL was phenotypically identified in 26% (13/50 of cases, while AmpC activity was detected in two ESβL-producing E. coli isolates. All ESβL-producing E. coli were positive for the CTX-M gene, eleven isolates carried blaCTX-M-15, and two isolates carried blaCTX-M-14 gene. Two CTX-M-positive E. coli isolates carried blaCMY-2. Conclusions. The alimentary tract is a significant reservoir for ESβL- and/or AmpC-producing E. coli, which may lead to nosocomial infection.

  5. Prevalence of extended-spectrum beta-lactamase-producing bacteria in food

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    Tham J

    2012-10-01

    Full Text Available Johan Tham,1 Mats Walder,2 Eva Melander,2,3 Inga Odenholt11Infectious Diseases Unit, Department of Clinical Sciences, 2Medical Microbiology, Department of Laboratory Medicine, Lund University, Malmö, Sweden; 3Department of Infection Control, Laboratory Medicine, Skåne County, SwedenAbstract: Extended-spectrum β-lactamase (ESBL-producing Enterobacteriaceae with Cefotaximase–München (CTX-M enzymes are rapidly increasing worldwide and pose a threat to health care. ESBLs with CTX-M enzymes have been isolated from animals and different food products, but it is unknown if food imported from the Mediterranean area may be a possible reservoir of these bacteria. During 2007–2008, swab samples from food across different retail outlets (mostly food from the Mediterranean countries and Swedish chicken were collected. Escherichia coli strains from Swedish meat and E. coli isolates from unspecified food from a Swedish food testing laboratory were also examined. In 349 of the 419 swab samples, growth of Enterobacteriaceae was found. In most of the samples, there was also growth of Gram-negative environmental bacteria. Air dry-cured products contained significantly less Enterobacteriaceae isolates compared to lettuces; however, none of the examined Enterobacteriaceae harbored ESBLs. This study did not support the theory that imported food from the Mediterranean area or Swedish domestic food might constitute an important vehicle for the dissemination of ESBL-producing Enterobacteriaceae; however, a spread from food to humans may have occurred after 2008.Keywords: ESBL, antibiotic resistance, zoonosis, food, Enterobacteriaceae

  6. Temporal trends and risk factors for extended-spectrum beta-lactamase-producing Escherichia coli in adults with catheter-associated urinary tract infections

    OpenAIRE

    Spadafino, Joseph T; Cohen, Bevin; Liu, JianFang; Larson, Elaine

    2014-01-01

    Background Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli cause up to 10% of catheter-associated urinary tract infections (CAUTI). We report changes in ESBL prevalence among CAUTIs in an adult acute care hospital from 2006-2012 and describe factors associated ESBL-production among E. coli CAUTI. Findings Data on patients ≥18 years discharged from a 647-bed tertiary/quaternary care hospital (2006-2012), a 221-bed community hospital (2007-2012), and a 914-bed tertiary/quater...

  7. Risk factors and prognosis of nosocomial bloodstream infections caused by extended-spectrum-beta-lactamase-producing Escherichia coli.

    Science.gov (United States)

    Rodríguez-Baño, Jesús; Picón, Encarnación; Gijón, Paloma; Hernández, José Ramón; Cisneros, Jose M; Peña, Carmen; Almela, Manuel; Almirante, Benito; Grill, Fabio; Colomina, Javier; Molinos, Sonia; Oliver, Antonio; Fernández-Mazarrasa, Carlos; Navarro, Gemma; Coloma, Ana; López-Cerero, Lorena; Pascual, Alvaro

    2010-05-01

    Extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli (ESBLEC) is an increasing cause of community and nosocomial infections worldwide. However, there is scarce clinical information about nosocomial bloodstream infections (BSIs) caused by these pathogens. We performed a study to investigate the risk factors for and prognosis of nosocomial BSIs due to ESBLEC in 13 Spanish hospitals. Risk factors were assessed by using a case-control-control study; 96 cases (2 to 16% of all nosocomial BSIs due to E. coli in the participating centers) were included; the most frequent ESBL was CTX-M-14 (48% of the isolates). We found CTX-M-15 in 10% of the isolates, which means that this enzyme is emerging as a cause of invasive infections in Spain. By repetitive extragenic palindromic sequence-PCR, most isolates were found to be clonally unrelated. By multivariate analysis, the risk factors for nosocomial BSIs due to ESBLEC were found to be organ transplant (odds ratio [OR]=4.8; 95% confidence interval [CI]=1.4 to 15.7), the previous use of oxyimino-beta-lactams (OR=6.0; 95% CI=3.0 to 11.8), and unknown BSI source (protective; OR=0.4; 95% CI=0.2 to 0.9), and duration of hospital stay (OR=1.02; 95% CI=1.00 to 1.03). The variables independently associated with mortality were a Pitt score of >1 (OR=3.9; 95% CI=1.2 to 12.9), a high-risk source (OR=5.5; 95% CI=1.4 to 21.9), and resistance to more than three antibiotics, apart from penicillins and cephalosporins (OR=6.5; 95% CI=1.4 to 30.0). Inappropriate empirical therapy was not associated with mortality. We conclude that ESBLEC is an important cause of nosocomial BSIs. The previous use of oxyimino-beta-lactams was the only modifiable risk factor found. Resistance to drugs other than penicillins and cephalosporins was associated with increased mortality.

  8. Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-Producing Escherichia coli among Uropathogens of Pediatrics in North of Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Rezai

    2015-01-01

    Full Text Available Escherichia coli remains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producing E. coli isolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of the E. coli isolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR for the presence or absence of CTX, TEM, SHV, GES, and VEB beta-lactamase genes. About 30.5% of isolated E. coli was ESBL-producing strain. The TEM gene was the most prevalent (49% followed by SHV (44%, CTX (28%, VEB (8%, and GES (0% genes. The ESBL-producing E. coli isolates were susceptible to carbapenems (66% and amikacin (58% and showed high resistance to cefixime (99%, colistin (82%, and ciprofloxacin (76%. In conclusion, carbapenems were the most effective antibiotics against ESBl-producing E. coli in urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise.

  9. [Fosfomycin susceptibility of urinary Escherichia coli isolates producing extended-spectrum beta-lactamase according to CLSI and EUCAST recommendations].

    Science.gov (United States)

    Cağan Aktaş, Sabahat; Gençer, Serap; Batırel, Ayşe; Hacıseyitoğlu, Demet; Ozer, Serdar

    2014-10-01

    The increasing rate of antibiotic resistance in Escherichia coli, the most common pathogen of urinary tract infections (UTIs), leads to difficulties in choosing appropriate antibiotic treatment and achieving treatment success. The aim of this study was to investigate in vitro activity of fosfomycin, presented as a favorable choice for the treatment of UTIs caused especially by extended-spectrum beta-lactamase (ESBL)-producing strains. A total of 244 E.coli strains, of them 118 were ESBL positive and 126 were negative, isolated from urine samples of inpatients and outpatients between May 2011-May 2012, were included in the study. Antibiotic susceptibilities of the isolates were determined by disk diffusion method (DDM) and ESBL production was confirmed by double-disc diffusion method according to the CLSI (Clinical and Laboratory Standards Institute) recommendations. Minimum inhibitor concentration (MIC) values for fosfomycin were detected by E-test method. Fosfomycin zone diameters and MIC values of isolates were interpreted according to the breakpoints of both CLSI and EUCAST (European Committee on Antimicrobial Susceptibility Testing). Susceptibilities of ESBL positive and negative isolates to fosfomycin and other antibiotics, and the results of fosfomycin susceptibility tests obtained by different methods were compared. The correlation between fosfomycin zone diameters and MIC values was calculated. In the study, the resistance rates of ESBL-producing isolates to ciprofloxacin, trimethoprim-sulfamethoxazole, gentamicin and amikacin were detected as 67%, 51%, 51% and 19%, respectively, while those rates were as 9%, 21%, 4% and 11%, respectively in non-ESBL producers. The difference between the two groups were found statistically significant (p< 0.001). Fosfomycin resistance of ESBL-producing and non-producing isolates were 3% and 1%, respectively, indicating no significant difference between the two groups (p= 0.356). According to fosfomycin MIC breakpoints

  10. Phenotypic detection of beta-lactamases production in enterobacteriaceae

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    Ćirković Ivana

    2014-01-01

    Full Text Available Introduction. Beta-lactam antibiotics are the most commonly used antibacterial drugs. However, many bacteria have developed resistance to these antibiotics, and the most common form of resistance is the production of beta-lactamase enzymes. Many members of the Enterobacteriaceae family produce different types of these enzymes. Objective. The aim of this study was to perform phenotypic detection of production and identification of beta-lactamase type in Enterobacteriaceae isolated from different clinical specimens from patients hospitalized in the Clinical Center of Serbia. Methods. The strains of Enterobacteriaceae were collected between November 2011 and January 2012 in the laboratory of the Clinical Center of Serbia. The isolates were identified according to the standard microbiology procedures and confirmed by the Vitek2 automated system. Antimicrobial susceptibility testing was performed by the disk diffusion method, and the phenotypic detection of production and identification of betalactamases was performed according to previously described methodologies. Results. In this study, a total of 172 Enterobacteriaceae strains were isolated. Further testing was performed on 54/145 (37.2% strains showing decreased susceptibility to beta-lactam antibiotics: 13/85 (15.3% Escherichia coli, 31/46 (67.4% Klebsiella pneumoniae and 10/14 (71.4% Proteus mirabilis. Among them, 40/145 (27.6% strains produced extended spectrum betalactamases (ESBLs, 9/145 (6.2% - AmpC, 1/145 (0.7% - K1 beta-lactamase and 4/145 (2.8% - carbapenemases. Carbapenemases were predominantly detected in K. pneumoniae (75%. Conclusion. Enterobacteriaceae produce different types of betalactamases, and the most common type in our study was ESBLs. Production of carbapenemases detected in Enterobacteriaceae is also an associated problem. [Projekat Ministarstva nauke Republike Srbije, br. ON 175039

  11. Detection of a IMP-4 type metal beta lactamase-producing Klebsiella pneumonia highly resistant to carbapenem drugs%一株高度耐碳青霉烯类药物的肺炎克雷伯菌耐药性研究

    Institute of Scientific and Technical Information of China (English)

    王旭明; 李天娇; 莫成锦

    2011-01-01

    Objective To understand the resistant mechanism of a Klebsiella pneumonia strain highly resistant to to carbapenem drugs. Methods Both broth microdilution and Etest method were usef for antimicrobial susceptibility test of Klebsiella pneumonia to carbapenemases, modified Hodge test and double disk synergy method were uxed for phenotype detection and multiple groups of carbapenem resistance related gene primers PCR and sequencing was used for genotype determination with assistance of Beijing University Institute of Clinical Pharmacology. Results Klebsiella pneumonia resistant to on commonly used clinical imipenem (mic>32ug/ml),meropenem (mic>32ug/ml),the first to fourth generation of cephalosporins, quinolone and gentamicin, cefoxitin, aztreonam trimethoprim/sulphamethoxazole, telracycline minocycline, ampicillin, ampicillin/sulbactam, piperacillin, piperacillin/tazobactam, amoxicillin/clavulanic acid, cefoperazone/sulbactam, but sensitive to amikacin and polymyxin B. carbapenem resistance gene was blaIMP-4. Conclusion IMP-4 type metal lactamase Klebsiella pneumonia resistant to most common antibacterials has been detected in this hospital and attention be paid to monitoring and treatment.%目的 了解从临床患者病灶中分离到的一株高度耐碳青霉烯类药物的肺炎克雷伯菌的耐药机制.方法 药敏试验采用微量肉汤稀释法与etest法,碳青霉烯酶表型检测采用改良Hodge试验和双纸片增效法,其基因型测定采用多组碳青霉烯耐药相关基因引物PCR并测序,由北京大学临床药理研究所负责完成.结果 药敏测试结果除对阿米卡星和多粘菌素敏感外,对临床常用亚胺培南(mic>32ug/ml)、美罗培南(mic>32ug/ml)、一至四代的头孢菌素类、硅诺酮类以及庆大霉素、头孢西丁、氨曲南、复方新诺明、四环素、美满霉素、氨苄西林、氨苄西林/舒巴坦、哌拉西林、哌拉西林/他唑巴坦、阿莫西林/棒酸、头孢哌酮/舒巴坦,

  12. Variations in the Produce-Associated Microbiota and the Occurrence Frequency of Extended-Spectrum Beta-Lactamase Gram-Negative Bacteria Result in Different Level of Ingestion Risks

    KAUST Repository

    Bokhari, Osama

    2016-04-01

    A monitoring effort that spanned across one and a half years was conducted to examine three types of produce-associated microbiota. Produce type was determined to be the predominant factor affecting the microbial communities. Other significant factors that resulted in differences in the microbial populations were the origin and sampling date. Specifically, produce-associated microbiota among lettuce and tomatoes clustered based on the sampling period. Through molecular and cultivation-based approaches, sporadic presence of extended spectrum beta-lactamase (ESBL)-positive Klebsiella pneumoniae and Acinetobacter baumannii was detected on lettuce and cucumbers during certain periods of sampling. Quantitative microbial risk assessment denoted varying levels of ingestion risks associated with different types of produce. In particular, the risks arising from ESBL-positive K. pneumoniae in the lettuce were higher than the acceptable annual risk of 10-4. Commonly used approaches to clean and wash the produce were insufficient in removing majority of the produce-associated microbiota. More invasive cleaning approaches or thorough cooking of the produce would be required to mitigate the associated risks. Most of the current reports of ESBL-positive bacterial isolates were identified in nosocomial environment. However, the carriage of such drug-resistant bacteria in food that is consumed daily

  13. Pseudomonas aeruginosa isolates from patients with cystic fibrosis have different beta-lactamase expression phenotypes but are homogeneous in the ampC-ampR genetic region

    DEFF Research Database (Denmark)

    Campbell, J I; Ciofu, O; Høiby, N

    1997-01-01

    Pseudomonas aeruginosa isolates from 1 of 17 cystic fibrosis patients produced secondary beta-lactamase in addition to the ampC beta-lactamase. Isolates were grouped into three beta-lactamase expression phenotypes: (i) beta-lactam sensitive, low basal levels and inducible beta-lactamase production...

  14. Meta-analysis of proportion estimates of Extended-Spectrum-Beta-Lactamase-producing Enterobacteriaceae in East Africa hospitals

    DEFF Research Database (Denmark)

    Sonda, Tolbert; Kumburu, Happiness; van Zwetselaar, Marco;

    2016-01-01

    Background: A high proportion of Extended-Spectrum-Beta-Lactamase (ESBL) producing Enterobacteriaceae is causing common infections in all regions of the world. The burden of antibiotic resistance due to ESBL in East Africa is large but information is scarce and thus it is unclear how big...... the problem really is. To gain insight into the magnitude and molecular epidemiology of ESBL-producing Enterobacteriaceae in East Africa a literature search was performed in PubMed on 31 July 2015 to retrieve articles with relevant information on ESBL. Methods and results: Meta-analysis was performed...... to determine overall proportion estimate of ESBL-producing Enterobacteriaceae. A total of 4076 bacterial isolates were included in the analysis. The overall pooled proportion of ESBL-producing Enterobacteriaceae among included surveys done in East African hospitals was found to be 0. 42 (95 % CI: 0...

  15. Plasmid-mediated extended-spectrum beta-lactamase-producing strains of Enterobacteriaceae isolated from diabetes foot infections in a Brazilian diabetic center

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    R.N. Motta

    2003-04-01

    Full Text Available We bacteriologically analyzed 156 species of Enterobacteriaceae, isolated from 138 patients with community-acquired diabetic foot ulcers, in a prospective study made at a diabetic center and at the Federal University of Ceará, Brazil, from March, 2000, to November, 2001.The samples were cultured using selective media, and identification, susceptibility tests and detection of plasmid-mediated-extended-spectrum-beta-lactamase (ESBL producing strains were made with conventional and automated methods. The most frequently occurring pathogens were K. pneumoniae (21.2%, Morganella morganii (19.9% and E. coli (15.4%. High resistance rates were noted for ampicillin, first generation cephalosporin, trimethoprim/sulfamethoxazole, tetracycline, amoxicillin-clavulanic acid and chloramphenicol. ESBL-producing strains were detected in 6% of the patients. Resistance among gram-negative bacteria has become increasingly common, even in community-acquired infections.

  16. Time-kill and synergism studies of ceftobiprole against Enterococcus faecalis, including beta-lactamase-producing and vancomycin-resistant isolates.

    Science.gov (United States)

    Arias, Cesar A; Singh, Kavindra V; Panesso, Diana; Murray, Barbara E

    2007-06-01

    Ceftobiprole (BAL9141) is an investigational cephalosporin with broad in vitro activity against gram-positive cocci, including enterococci. Ceftobiprole MICs were determined for 93 isolates of Enterococcus faecalis (including 16 beta-lactamase [Bla] producers and 17 vancomycin-resistant isolates) by an agar dilution method following the Clinical and Laboratory Standards Institute recommendations. Ceftobiprole MICs were also determined with a high inoculum concentration (10(7) CFU/ml) for a subset of five Bla producers belonging to different previously characterized clones by a broth dilution method. Time-kill and synergism studies (with either streptomycin or gentamicin) were performed with two beta-lactamase-producing isolates (TX0630 and TX5070) and two vancomycin-resistant isolates (TX2484 [VanB] and TX2784 [VanA]). The MICs of ceftobiprole for 50 and 90% of the isolates tested were 0.25 and 1 microg/ml, respectively. All Bla producers and vancomycin-resistant isolates were inhibited by concentrations of Ceftobiprole MICs at a high inoculum concentration for a subset of five Bla(+) E. faecalis isolates were ceftobiprole (0.5 microg/ml) and streptomycin (25 microg/ml) was synergistic against Bla(+) TX0630 and TX5070. Ceftobiprole (0.5 microg/ml) plus gentamicin (10 microg/ml) was synergistic against VanB isolate TX2484 and showed enhanced killing, but not synergism, against TX2784 (VanA), despite the absence of high-level resistance to gentamicin. In conclusion, ceftobiprole exhibited good in vitro activity against E. faecalis, including Bla(+) and vancomycin-resistant strains, and exhibited synergism with aminoglycosides against selected isolates.

  17. Genomic Dissection of Travel-Associated Extended-Spectrum-Beta-Lactamase-Producing Salmonella enterica Serovar Typhi Isolates Originating from the Philippines: a One-Off Occurrence or a Threat to Effective Treatment of Typhoid Fever?

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Leekitcharoenphon, Pimlapas; Mikoleit, Matthew;

    2015-01-01

    One unreported case of extended-spectrum-beta-lactamase (ESBL)-producing Salmonella enterica serovar Typhi was identified, whole-genome sequence typed, among other analyses, and compared to other available genomes of S. Typhi. The reported strain was similar to a previously published strain harbo...

  18. Prolonged colonisation with Escherichia coli O25:ST131 versus other extended-spectrum beta-lactamase-producing E. coli in a long-term care facility with high endemic level of rectal colonisation, the Netherlands, 2013 to 2014

    NARCIS (Netherlands)

    Overdevest, Ilse; Haverkate, Manon; Veenemans, Jacobien; Hendriks, Yvonne; Verhulst, Carlo; Mulders, Ans; Couprie, Willemijn; Bootsma, Martin; Johnson, James; Kluytmans, Jan

    2016-01-01

    The extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clone ST131 (ESBL-ST131) has spread in healthcare settings worldwide. The reasons for its successful spread are unknown, but might include more effective transmission and/or longer persistence. We evaluated the colonisation dynam

  19. Laboratory surveillance for prospective plasmid-mediated AmpC beta-lactamases in the Kinki region of Japan.

    Science.gov (United States)

    Yamasaki, Katsutoshi; Komatsu, Masaru; Abe, Noriyuki; Fukuda, Saori; Miyamoto, Yugo; Higuchi, Takeshi; Ono, Tamotsu; Nishio, Hisaaki; Sueyoshi, Noriyuki; Kida, Kaneyuki; Satoh, Kaori; Toyokawa, Masahiro; Nishi, Isao; Sakamoto, Masako; Akagi, Masahiro; Nakai, Isako; Kofuku, Tomomi; Orita, Tamaki; Wada, Yasunao; Jikimoto, Takumi; Kinoshita, Shohiro; Miyamoto, Kazuaki; Hirai, Itaru; Yamamoto, Yoshimasa

    2010-09-01

    Extended-spectrum beta-lactamases, plasmid-mediated AmpC beta-lactamases (PABLs), and plasmid-mediated metallo-beta-lactamases confer resistance to many beta-lactams. In Japan, although several reports exist on the prevalence of extended-spectrum beta-lactamases and metallo-beta-lactamases, the prevalence and characteristics of PABLs remain unknown. To investigate the production of PABLs, a total of 22,869 strains of 4 enterobacterial species, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis, were collected during six 6-month periods from 17 clinical laboratories in the Kinki region of Japan. PABLs were detected in 29 (0.13%) of 22,869 isolates by the 3-dimensional test, PCR analysis, and DNA sequencing analysis. PABL-positive isolates were detected among isolates from 13 laboratories. Seventeen of 13,995 (0.12%) E. coli isolates, 8 of 5,970 (0.13%) K. pneumoniae isolates, 3 of 1,722 (0.17%) K. oxytoca isolates, and 1 of 1,182 (0.08%) P. mirabilis isolates were positive for PABLs. Of these 29 PABL-positive strains, 20 (69.0%), 6 (20.7%), 2 (6.9%), and 1 (3.4%) carried the genes for CMY-2, DHA-1, CMY-8, and MOX-1 PABLs, respectively. Pattern analysis of randomly amplified polymorphic DNA and pulsed-field gel electrophoretic analysis revealed that the prevalence of CMY-2-producing E. coli strains was not due to epidemic strains and that 3 DHA-1-producing K. pneumoniae strains were identical, suggesting their clonal relatedness. In conclusion, the DHA-1 PABLs were predominantly present in K. pneumoniae strains, but CMY-2 PABLs were predominantly present in E. coli strains. The present findings will provide significant information to assist in preventing the emergence and further spread of PABL-producing bacteria.

  20. Carbapenem-resistant Serratia marcescens isolates producing Bush group 2f beta-lactamase (SME-1) in the United States: results from the MYSTIC Programme.

    Science.gov (United States)

    Gales, A C; Biedenbach, D J; Winokur, P; Hacek, D M; Pfaller, M A; Jones, R N

    2001-02-01

    Two carbapenem (imipenem, meropenem)-resistant Serratia marcescens strains were isolated in the United States (Chicago, IL) through the 1999 MYSTIC (Meropenem Yearly Susceptibility Test Information Collection) Programme. The S. marcescens antimicrobial susceptible patterns were: susceptible to ceftriaxone, ceftazidime, and cefepime (MICs, 32 microg/ml) and aztreonam (MIC, > = 16 microg/ml). Each S. marcescens isolate shared an identical epidemiologic type (ribotype and PFGE) and the outer membrane protein profile was also identical to those of the wild type susceptible strains from the same medical center. The PCR utilizing bla(sme-1) primers amplified a gene product that was identified as consistent with SME-1 after DNA sequencing. Imipenem and meropenem resistance due to production of carbapenem-hydrolyzing enzymes among clinical isolates is still very rare, but microbiology laboratories should be aware of these chromosomally encoded enzymes among class C beta-lactamases producing enteric bacilli such as S. marcescens and Enterobacter cloacae.

  1. Extended-spectrum beta-lactamase-producing bacteria are not detected in supragingival plaque samples from human fecal carriers of ESBL-producing Enterobacteriaceae

    Directory of Open Access Journals (Sweden)

    Arne Søraas

    2014-08-01

    Full Text Available Background: The prevalence of infections caused by Cefotaximase-Munich (CTX-M-type extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E has rapidly increased during the past 15 years. Enterobacteriaceae are commonly found in the gastrointestinal tract and long-term intestinal carriage is considered important for the spread of ESBL and as a source of clinical infections. Oral biofilm such as supragingival plaque is known to contain numerous antibiotic resistance determinants and may also represent a poorly investigated site for ESBL carriage and further spread. Objective: To investigate possible carriage of ESBL-producing bacteria in supragingival plaque of known fecal carriers of these bacteria. Design: We screened for the presence of aerobic and anaerobic ESBL-producing bacteria and blaCTX-M in supragingival plaque samples from healthy human adults with culture-verified fecal carriage of CTX-M-producing Escherichia coli. The presence or absence of Enterobacteriaceae and ESBL-producing bacteria in plaque samples was evaluated using culture-based methods and consensus CTX-M PCR. Results: Oral samples were obtained from 17 participants with known previous carriage of ESBL-producing E. coli. No ESBL-producing bacteria or ESBL genes were detected using culture-based and molecular methods. One colony of Rahnella aquatilis harboring the class A ESBL gene bla RAHN-1/2 was identified in an oral sample from one of the participants. Conclusion: This pilot study supports the notion that the presence of CTX-M-producing bacteria is uncommon in oral plaque of healthy human adult fecal carriers. Due to the limited number of persons tested, a low prevalence of oral ESBL-carriage in healthy adults or carriage in selected groups of patients cannot be excluded. To our knowledge, this is the first description of an R. aquatilis with the RAHN-1/2 gene in the oral cavity.

  2. Emergence of KPC-producing Klebsiella pneumoniae in Italy

    Directory of Open Access Journals (Sweden)

    Bossa Maria C

    2010-02-01

    Full Text Available Abstract Background The emergence of KPC-producing K. pneumoniae has now become a global concern. KPC beta-lactamases are plasmid-borne and, like extended spectrum beta lactamases (ESBLs, can accumulate and transfer resistance determinants to other classes of antibiotics. Therefore, infection control guidelines on early identification and control of the spread of organisms carrying these resistant determinants are needed. Findings Klebsiella pneumoniae carbapenemase (KPC was detected in two isolates of carbapenem-resistant K. pneumoniae obtained from patients at an Italian teaching hospital. The first strain was isolated from a culture drawn from a central venous device (CVC in a patient with Crohn's disease who was admitted to a gastroenterology ward. The second was isolated from a urine sample collected from an indwelling urinary catheter in an intensive care unit (ICU patient with a subdural haematoma. The patients had not travelled abroad. Both isolates were resistant to all β-lactams and were susceptible to imipenem and meropenem but resistant to ertapenem. Isolates also showed resistance to other classes of non-β-lactam antibiotics, such as quinolones, aminoglycosides (with the exception for amikacin, trimethoprim-sulfamethoxazole (TMP-SMX and nitrofurantoin. They were determined to contain the plasmid encoding the carbapenemase gene bla-KPC and were also positive in the Hodge test. Conclusions This is the second report of KPC-producing isolates in Italy, but the first concerning KPC type 2 gene, and it may have important implications for controlling the transmission of microorganisms resistant to antibiotics.

  3. Synthesis of silver nanoparticles using the Streptomyces coelicolor klmp33 pigment: An antimicrobial agent against extended-spectrum beta-lactamase (ESBL) producing Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Manikprabhu, Deene; Lingappa, K., E-mail: lingappak123@gmail.com

    2014-12-01

    The increasing emergence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli) occurred mainly due to continuous persistent exposure to antibiotics causing high morbidity and mortality so studies in controlling this infection are required. In the present investigation, we developed a synthesis for silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33, and assessed the antimicrobial activity of these nanoparticles against ESBL producing E. coli. The ESBL producing E. coli were isolated from urine samples collected from the Gulbarga region in India. As can been seen from our studies, the silver nanoparticles having irregular shapes and size of 28–50 nm showed remarkable antimicrobial activity and moreover the synthesis time is just 20 min and thus the same can be used for formulating pharmaceutical remedies. - Highlights: • Silver nanoparticle synthesis by photo-irradiation method in just 20 min • Isolation of ESBL producing E. coli from urine samples from the Gulbarga region. • Antimicrobial activity of silver nanoparticles against ESBL producing E. coli • The minimum inhibitory concentration of silver nanoparticles against ESBL producing E. coli was 40 μL.

  4. The profile of antibiotics resistance and integrons of extended-spectrum beta-lactamase producing thermotolerant coliforms isolated from the Yangtze River basin in Chongqing

    Energy Technology Data Exchange (ETDEWEB)

    Chen Hao [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China); Shu Weiqun, E-mail: west2003@sohu.co [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China); Chang Xiaosong; Chen Jian; Guo Yebin; Tan Yao [Department of Environmental Hygiene, School of Military Preventive Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038 (China)

    2010-07-15

    The spreading of extended-spectrum {beta}-lactamases (ESBL)-producing thermotolerant coliforms (TC) in the water environment is a threat to human health but little is known about ESBL-producing TCs in the Yangtze River. We received 319 ESBL-producing stains obtained from the Chongqing basin and we investigated antibiotic susceptibility, bla gene types and the presence of integrons and gene cassettes. 16.8% of TC isolates were ESBL-producing bacteria and bla{sub TEM+CTx-M} was the predominant ESBL type. 65.2% of isolates contained class 1 integrons, but only 3 carried intI 2. Gene cassettes were amplified and sequenced. aadA, drfA, cmlA, sat1, aar3 and two ORF cassettes were found. In conclusion, Yangtze River is heavily polluted by ESBL-producing TC bacteria and the combined bla gene type could enhance antibiotic resistance. Class 1 integrons were widespread in ESBL-producing isolates and play an important role in multi-drug resistance. Characterization of gene cassettes could reveal the dissemination of antibiotic resistance genes. - Yangtze River is heavily polluted by ESBL-producing TC bacteria and Class 1 integrons play an important role in multi-drug resistance.

  5. Occurrence and sensitivity profile of extended spectrum beta-lactamase-producing Enterobacteriaceae at a tertiary hospital in Southern Brazil

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    Cristina Letícia Rugini

    2015-12-01

    Full Text Available Abstract: INTRODUCTION: Nosocomial infections are closely associated with antimicrobial drug resistance. One of the most important mechanisms of resistance to β-lactam antibiotics is the production of extended spectrum β-lactamases (ESBLs. The objective of the present study was to evaluate the prevalence and antimicrobial susceptibility profile of ESBL-producing strains and to assess the evolution of antimicrobial drug resistance between 2007 and 2013 at the Hospital São Vicente de Paulo, Passo Fundo, State of Rio Grande do Sul, Brazil. METHODS: We conducted a descriptive, observational, cross-sectional study. Bacterial culture was performed from January to December 2013. The antimicrobial susceptibility profile of these cultures was determined using the disk diffusion method. Phenotypic screening for ESBL production was performed using the disk approximation method. RESULTS : We analyzed a total of 19,112 cultures, 11.5% of which were positive for Enterobacteriaceae. Of these, 30.3% of the isolates were positive for ESBL production, and the most prevalent species was Klebsiella sp. (37.5%. Over 95% of these isolates showed reduced susceptibility to all cephalosporins, aztreonam, and amoxicillin/clavulanic acid. The isolates also showed high sensitivity to the following antimicrobials: amikacin, meropenem, and piperacillin/tazobactam. Overall, the resistance rates among ESBL-producing Enterobacteriaceae decreased from 2007 to 2013. CONCLUSIONS : In our hospital, the increased sensitivity to certain antimicrobial agents seems to be directly related to the implementation of improvements in the methods to prevent and control nosocomial infections in addition to the natural development of other resistance mechanisms.

  6. Genomic dissection of travel-associated extended-spectrum-beta-lactamase-producing Salmonella enterica serovar typhi isolates originating from the Philippines: a one-off occurrence or a threat to effective treatment of typhoid fever?

    Science.gov (United States)

    Hendriksen, Rene S; Leekitcharoenphon, Pimlapas; Mikoleit, Matthew; Jensen, Jacob Dyring; Kaas, Rolf Sommer; Roer, Louise; Joshi, Heena B; Pornruangmong, Srirat; Pulsrikarn, Chaiwat; Gonzalez-Aviles, Gladys D; Reuland, E Ascelijn; Al Naiemi, Nashwan; Wester, Astrid Louise; Aarestrup, Frank M; Hasman, Henrik

    2015-02-01

    One unreported case of extended-spectrum-beta-lactamase (ESBL)-producing Salmonella enterica serovar Typhi was identified, whole-genome sequence typed, among other analyses, and compared to other available genomes of S. Typhi. The reported strain was similar to a previously published strain harboring blaSHV-12 from the Philippines and likely part of an undetected outbreak, the first of ESBL-producing S. Typhi.

  7. Rectal carriage of extended-spectrum beta-lactamase-producing gram-negative bacilli in community settings in Madagascar.

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    Perlinot Herindrainy

    Full Text Available BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacteria (ESBL-PE emerged at the end of the 1980s, causing nosocomial outbreaks and/or hyperendemic situations in hospitals and long-term care facilities. In recent years, community-acquired infections due to ESBL-PE have spread worldwide, especially across developing countries including Madagascar. OBJECTIVES: This study aimed to determine the prevalence and risk factors of intestinal carriage of ESBL-PE in the community of Antananarivo. METHODS: Non-hospitalized patients were recruited in three health centers in different socio economic settings. Fresh stool collected were immediately plated on Drigalski agar containing 3 mg/liter of ceftriaxone. Gram-negative bacilli species were identified and ESBL production was tested by a double disk diffusion (cefotaxime and ceftazidime +/- clavulanate assay. Characterization of ESBLs were perfomed by PCR and direct sequencing. Molecular epidemiology was analysed by Rep-PCR and ERIC-PCR. RESULTS: 484 patients were screened (sex ratio  =  1.03, median age 28 years. 53 ESBL-PE were isolated from 49 patients (carrier rate 10.1%. The isolates included Escherichia coli (31, Klebsiella pneumoniae (14, Enterobacter cloacae (3, Citrobacter freundii (3, Kluyvera spp. (1 and Pantoae sp. (1. In multivariate analysis, only the socioeconomic status of the head of household was independently associated with ESBL-PE carriage, poverty being the predominant risk factor. CONCLUSIONS: The prevalence of carriage of ESBL in the community of Antananarivo is one of the highest reported worldwide. This alarming spread of resistance genes should be stopped urgently by improving hygiene and streamlining the distribution and consumption of antibiotics.

  8. Epidemiology and molecular characterization of extended-spectrum beta-lactamase-producing Enterobacter spp., Pantoea agglomerans, and Serratia marcescens isolates from a Bulgarian hospital.

    Science.gov (United States)

    Markovska, Rumyana Donkova; Stoeva, Temenuga Jekova; Bojkova, Kalina Dineva; Mitov, Ivan Gergov

    2014-04-01

    Forty-two extended-spectrum beta-lactamase (ESBL)-producing isolates of Enterobacter aerogenes, Enterobacter cloacae, Pantoea agglomerans, and Serratia marcescens, collected consecutively during the period January-November 2011 from the University Hospital in Varna, Bulgaria, were studied to characterize their ESBLs by isoelectric focusing, group-specific PCR, and sequencing. The epidemiological relationship was evaluated by random amplified polymorphic DNA analysis (RAPD). Transferability of ESBL genes was determined by conjugation experiments. Plasmid analysis was done by replicon typing and PstI fingerprinting. The overall rate of ESBL production was 20%. The most widespread enzyme was CTX-M-3, found in 64%. It was dominant in E. aerogenes (100%) and S. marcescens (83%). SHV-12, CTX-M-3, and CTX-M-15 were found among E. cloacae isolates in 50%, 35%, and 45%, respectively. Three main CTX-M-3-producing epidemic clones of E. aerogenes and S. marcescens have been detected. Among E. cloacae isolates, six different RAPD profiles were discerned. The plasmids harboring blaCTX-M-3 belonged to IncL/M type and demonstrated similar PstI fingerprinting profiles. IncFII plasmids were detected in two CTX-M-15-producing E. cloacae isolates. Our results demonstrate wide intrahospital dissemination of clonal E. aerogenes and S. marcescens isolates, carrying IncL/M conjugative plasmids.

  9. Extended-spectrum beta-lactamase-producing bacteria in a tertiary care hospital in Madrid: epidemiology, risk factors and antimicrobial susceptibility patterns

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    Ines Rubio-Perez

    2012-07-01

    Full Text Available Introduction: Extended-spectrum beta-lactamase (ESBL producing bacteria have been increasingly reported as causal agents of nosocomial infection worldwide. Resistance patterns vary internationally, and even locally, from one institution to the other. We investigated the clinical isolates positive for ESBL-producing bacteria in our institution, a tertiary care hospital in Madrid (Spain, during a 2-year period (2007–2008. Methods: Clinical and microbiological data were retrospectively reviewed. Two hundred and nineteen patients were included in the study. Results: Advanced age, diabetes, use of catheters, previous hospitalization and previous antibiotic treatment were some of the risk factors found among patients. Escherichia coli was the most frequent isolate, and urinary tract the most common site of isolation. Internal Medicine, Intensive Care Unit (ICU and General Surgery presented the highest number of isolates. There were no outbreaks during the study period. Antibiotic patterns showed high resistance rates to quinolones in all isolates. There was 100% sensitivity to carbapenems. Conclusion: Carbapenems continue to be the treatment of choice for ESBL-producing bacteria. Infection control measures are of great importance to avoid the spread of these nosocomial infections.

  10. Metallo-beta-lactamase producing Pseudomonas aeruginosa strains isolated in hospitals in Recife, PE, Brazil Produção de metalo-beta-lactase de linhagens de Pseudomonas aeruginosa isoladas em hospitais do Recife, PE, Brasil

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    Vera Magalhães

    2005-06-01

    Full Text Available Out of 24 nosocomial strains of Pseudomonas aeruginosa from Recife, Brazil, 15 (62% were metallo-beta-lactamase producers. Such isolates were resistant to main antipseudomonas drugs, except polymixyn B and aztreonam. The enzyme responsible for the carbapenem-resistance belongs to SPM-1 class, and the gene involved, blaspm-1, is likely plasmid located.De 24 linhagens hospitalares de Pseudomonas aeruginosa provenientes de Recife, Brasil, 15 (62% produziram metalo-beta-lactamase. Tais isolados foram resistentes às principais drogas antipseudomonas, exceto polimixina B e aztreonam. A enzima responsável pela resistência aos carbapanêmicos pertence à classe SPM-1 e o gene envolvido, blaspm-1, provavelmente é plasmidial.

  11. Beta-lactamases in Enterobacteriaceae in broilers

    NARCIS (Netherlands)

    Dierikx, C.M.

    2013-01-01

    Resistance to cephalosprins due to the production of extended spectrum beta-lactamases (ESBLs) or plasmid mediated AmpC beta-lactamases is increasingly found in infections in humans outside the hospital. The genes encoding for these beta-lactamases are located on mobile DNA (plasmids), which can be

  12. Evaluation of MicroScan ESBL confirmation panel for Enterobacteriaceae-producing, extended-spectrum beta-lactamases isolated in Japan.

    Science.gov (United States)

    Komatsu, Masaru; Aihara, Masanori; Shimakawa, Kouichi; Iwasaki, Mizuho; Nagasaka, Yoko; Fukuda, Saori; Matsuo, Shuji; Iwatani, Yoshinori

    2003-06-01

    We assessed use of the MicroScan ESBL confirmation panel (Dade Behring, Tokyo, Japan) for the detection of eight Enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBL) species. Of 137 bacterial strains isolated from patients in 32 hospitals in the Kinki area of Japan, 91 produced ESBL and comprised 60 bacteria (of E. coli, K. oxytoca, and K. pneumoniae) targeted by the NCCLS ESBL test and 31 non-target bacteria such as chromosomal AmpC-producing bacteria (e.g., Serratia marcescens, Enterobacter spp.). Sensitivity and specificity of the MicroScan panel for the target bacteria were 92% and 93%, respectively; sensitivity and specificity for non-target bacteria were 52% and 100%, respectively. There were 20 ESBL-positive strains that were not inhibited by clavulanic acid in the MicroScan panel (3 of 32 ESBL-producing E. coli strains, 1 of 24 K. pneumoniae, 1 of 4 K. oxytoca, 8 of 13 E. cloacae, and 7 of 14 S. marcescens), and most of them were bacteria not targeted by the NCCLS test. In 19 of the 20 strains, the synergy effect of clavulanic acid was observed in the modified-double-disk synergy test using only the cefepime-disk. Because these strains had high MICs of > or = 16 microg/ml for cephamycins such as cefoxitin and cefmetazole, these strains might produce high levels of AmpC in addition to ESBL. The MicroScan ESBL confirmation panel showed excellent performance in detecting target, but not other bacteria. Addition of cefepime and clavulanic acid to the MicroScan panel may significantly improve detection of non-target bacteria.

  13. Detection of Healthcare-Related Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Transmission Events Using Combined Genetic and Phenotypic Epidemiology.

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    Anne F Voor In 't Holt

    Full Text Available Since the year 2000 there has been a sharp increase in the prevalence of healthcare-related infections caused by extended-spectrum beta-lactamase (ESBL-producing Escherichia coli. However, the high community prevalence of ESBL-producing E. coli isolates means that many E. coli typing techniques may not be suitable for detecting E. coli transmission events. Therefore, we investigated if High-throughput MultiLocus Sequence Typing (HiMLST and/or Raman spectroscopy were suitable techniques for detecting recent E. coli transmission events.This study was conducted from January until December 2010 at Erasmus University Medical Center, Rotterdam, the Netherlands. Isolates were typed using HiMLST and Raman spectroscopy. A genetic cluster was defined as two or more patients carrying identical isolates. We used predefined definitions for epidemiological relatedness to assess healthcare-related transmission.We included 194 patients; strains of 112 patients were typed using HiMLST and strains of 194 patients were typed using Raman spectroscopy. Raman spectroscopy identified 16 clusters while HiMLST identified 10 clusters. However, no healthcare-related transmission events were detected. When combining data from both typing techniques, we identified eight clusters (n = 34 patients, as well as 78 patients with a non-cluster isolate. However, we could not detect any healthcare-related transmission in these 8 clusters.Although clusters were genetically detected using HiMLST and Raman spectroscopy, no definite epidemiological relationships could be demonstrated which makes the possibility of healthcare-related transmission events highly unlikely. Our results suggest that typing of ESBL-producing E. coli using HiMLST and/or Raman spectroscopy is not helpful in detecting E. coli healthcare-related transmission events.

  14. Determination of antimicrobial resistance pattern and Extended-Spectrum Beta Lactamases producing Pseudomonas aeruginosa strains isolated from clinical specimens of Hajar and Kashani Hospitals,Shahrekord 1387

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    Mana Shojapour

    2011-09-01

    Full Text Available Background: Pseudomonas aeruginosa is one of the leading causes of hospital infections in patients hospitalized for a 10 day period or over. It is also considered to be the most important cause of the burn wound infection. Approximately 75% of deaths in burned patients are due to wound infection and the subsequent septicemia. Clinical use of antibiotics has increasingly led to the global distribution of P. aeruginosa isolates with multi-drug resistance. The study was launched to determine the antimicrobial susceptibility pattern and the presence of the extended-spectrum-beta lactamase (ESBL in P.aeruginosa strains isolated from clinical specimens. Methods: Totally, 175 P. aeruginosa strains were isolated from clinical samples and identified by standard methods. The pattern of antimicrobial resistance was then performed on the isolates using Disk Agar Diffusion (DAD according to CLSI Guideline. Primary screening test for ESBL producing strains was performed by ceftazidim antibiotic disk using disk diffusion method. Combined disk method was used to confirm ESBL producing bacteria. Results: The rate of antimicrobial resistance of P.aeruginosa isolates were 64% to ticarcillin, 52.2% to cefepime, 68.6% to ticarcillin/clavolanic acid, 68.6% to ceftazidime, 67.4% to amikacin, 68.6% to gentamicin, 48% to imipenem, 77.7% to ciprofloxacin and 5.1% to polymixcine B. In the primary screening test, 120 isolates of P.aeruginosa strains were resistant to ceftazidime. In the combined disk method, 66 isolates (55% were positive for ESBLs. Conclusion: Polymixcine B was found to be the most effective antimicrobial agent in this study. Bacteria carrying ESBL genes may increase mortality and morbidity. Thus, their accurate diagnosis is of extreme importance to prevent from the treatment failure resulted from improper antibiotic administration.

  15. A COMPARATIVE-STUDY OF CLASS-D BETA-LACTAMASES

    NARCIS (Netherlands)

    LEDENT, P; RAQUET, [No Value; JORIS, B; VANBEEUMEN, J; FRERE, JM

    1993-01-01

    Three class-D beta-lactamases (OXA2, OXA1 and PSE2) were produced and purified to protein homogeneity. 6beta-lodopenicillanate inactivated the OXA2 enzyme without detectable turnover. Labelling of the same beta-lactamase with 6beta-iodo[H-3]penicillanate allowed the identification of Ser-70 as the a

  16. Varying high levels of faecal carriage of extended-spectrum beta-lactamase producing Enterobacteriaceae in rural villages in Shandong, China: implications for global health.

    Science.gov (United States)

    Sun, Qiang; Tärnberg, Maria; Zhao, Lingbo; Stålsby Lundborg, Cecilia; Song, Yanyan; Grape, Malin; Nilsson, Maud; Tomson, Göran; Nilsson, Lennart E

    2014-01-01

    Antibiotic resistance is considered a major threat to global health and is affected by many factors, of which antibiotic use is probably one of the more important. Other factors include hygiene, crowding and travel. The rapid resistance spread in Gram-negative bacteria, in particular extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae (ESBL-E), is a global challenge, leading to increased mortality, morbidity and health systems costs worldwide. Knowledge about resistance in commensal flora is limited, including in China. Our aim was to establish the faecal carriage rates of ESBL-E and find its association with known and suspected risk factors in rural residents of all ages in three socio-economically different counties in the Shandong Province, China. Faecal samples and risk-factor information (questionnaire) were collected in 2012. ESBL-E carriage was screened using ChromID ESBL agar. Risk factors were analysed using standard statistical methods. Data from 1000 individuals from three counties and in total 18 villages showed a high and varying level of ESBL-E carriage. Overall, 42% were ESBL-E carriers. At county level the carriage rates were 49%, 45% and 31%, respectively, and when comparing individual villages (n = 18) the rate varied from 22% to 64%. The high level of ESBL-E carriage among rural residents in China is an indication of an exploding global challenge in the years to come as resistance spreads among bacteria and travels around the world with the movement of people and freight. A high carriage rate of ESBL-E increases the risk of infection with multi-resistant bacteria, and thus the need for usage of last resort antibiotics, such as carbapenems and colistin, in the treatment of common infections.

  17. Frequent use of colistin-based drug treatment to eliminate extended-spectrum beta-lactamase-producing Escherichia coli in backyard chicken farms in Thai Binh Province, Vietnam.

    Science.gov (United States)

    Nakayama, Tatsuya; Jinnai, Michio; Kawahara, Ryuji; Diep, Khong Thi; Thang, Nguyen Nam; Hoa, Tran Thi; Hanh, Le Kieu; Khai, Pham Ngoc; Sumimura, Yoshinori; Yamamoto, Yoshimasa

    2017-01-01

    Reports of livestock infections with extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-E) are increasing. Based on interviews conducted over a 6-month period, we found that veterinarians in the Vietnamese province of Thai Binh prefer to prescribe colistin-based drugs (CBD) in chicken farms. We aimed to clarify whether CBD use selects for strains of colistin-resistant ESBL-E. With the cooperation of seven local households, we detected ESBL-E in chickens' feces after treating chickens with CBD. Phylogenetic groupings and the presence of CTX-M/AmpC genes were determined, and the multi-antibiotic susceptibility of isolates was analyzed. Our results showed that ESBL-E presented in seven chickens' feces from two households. Seventy-two percent of ESBL-E isolates harbored CTX-M9 and the phylogenetic group A; the colistin minimum inhibitory concentration (MIC) of all isolated ESBL-E ranged from 0.064 to 1 μg mL(-1). Moreover, ESBL-E isolates were used to experimentally select for colistin resistance, and the effect of commercial CBD on ESBL-E was investigated. The results showed that an ESBL-E strain with a colistin MIC of 4 μg mL(-1) was able to grow in media with CBD. Although CBD treatment was effective, in vitro experiments demonstrated that ESBL-E can easily acquire colistin resistance. Therefore, restrictions on colistin use are necessary to prevent the emergence of colistin-resistant bacteria.

  18. CTX-M-Type Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae Isolated from Cases of Bovine Mastitis in Japan

    OpenAIRE

    2014-01-01

    ABSTRACT Three Klebsiella pneumoniae isolates producing extended-spectrum beta-lactamase (ESBL) were obtained from three dairy cows with clinical mastitis in two farms in western Japan. Two of the 3 isolates from cows in different farms were able to transfer plasmids carrying the bla CTX-M-2 gene to Escherichia coli recipient. Pulsed-field gel electrophoresis (PFGE) patterns of the 2 isolates were different from each other, although restricted-fragment patterns of the two conjugative plasmids...

  19. High prevalence of fecal carriage of extended spectrum beta-lactamase/AmpC-producing Enterobacteriaceae in cats and dogs

    NARCIS (Netherlands)

    Hordijk, J.; Schoormans, A.; Kwakernaak, M.; Duim, B.; Broens, E.; Dierikx, C.M.; Mevius, D.J.; Wagenaar, J.A.

    2013-01-01

    Extended-spectrum-ß-lactamase (ESBL)/AmpC producing Enterobacteriaceae have been reported worldwide amongst isolates obtained from humans, food-producing animals, companion animals, and environmental sources. However, data on prevalence of fecal carriage of ESBL/AmpC producing Enterobacteriaceae in

  20. Incidence of extended spectrum beta lactamase producing Escherichia coli among patients, healthy individuals and in the environment.

    Science.gov (United States)

    George, E A; Sankar, S; Jesudasan, M V; Sudandiradoss, C; Nandagopal, B

    2014-01-01

    We investigated the faecal carriage of extended spectrum β-lactamases (ESBL) producing Escherichia coli in different groups of human subjects and in the environment. A total of 363 E. coli strains were isolated from stool samples of patients (n = 77), healthy subjects (n = 170) and from different environmental samples (n = 116). A total of 124 ESBL producing E. coli strains were isolated in this study. The frequency of ESBL producing E. coli was found to be highest (60.3%) among the strains isolated from patients, followed by healthy individuals (38%) and the environment (10.5%). The environment was observed to have a very low number of ESBL producing E. coli.

  1. A Study on Infections Caused By Metallo Beta Lactamase Producing Gram Negative Bacteria in Intensive Care Unit Patients

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    Debasrita Chakraborty

    2010-01-01

    Full Text Available Problem statement: Metallo Beta Lactamse (MBL producing bacteria is gradually increasing throughout the globe. There is no report of MBL producing bacteria from the city of Kolkata so far although it is a very big metropolice city in India. Thus this study was aimed to investigate the impact of this highly virulent group of bacteria in this city. Approach: In this experiment we studied the prevalence, following standard methods of isolation and identification techniques of these bacteria from clinical materials and also studied some characteristics and clinical data in relation to MBL producing bacterial infections in this locality. Results: It was seen that a high prevalence of MBL producing bacteria was present in this city and there were many differences between MBL producing bacterial infection in comparison to the MBL non producing bacterial infection, particularly in relation to age distribution, sex predominance, mortality rate, hematological changes, nature of primary diseases in which infection occurred. There were also some electron microscopic morphological alterations in MBL positive bacterial isolates. Conclusion: This study confirmed significant occurrence of MBL producing bacterial infections in Kolkata showing distinct clinic microbial changes in this type of infection.

  2. Detection of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in Market-Ready Chickens in Zambia

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    K. Chishimba

    2016-01-01

    Full Text Available The frequent administering of antibiotics in the treatment of poultry diseases may contribute to emergence of antimicrobial-resistant strains. The objective of this study was to detect the presence of extended-spectrum β-lactamase- (ESBL- producing Escherichia coli in poultry in Zambia. A total of 384 poultry samples were collected and analyzed for ESBL-producing Escherichia coli. The cultured E. coli isolates were subjected to antimicrobial susceptibility tests and the polymerase chain reaction for detection of blaCTX-M, blaSHV, and blaTEM genes. Overall 20.1%, 77/384, (95% CI; 43.2–65.5% of total samples analyzed contained ESBL-producing Escherichia coli. The antimicrobial sensitivity test revealed that 85.7% (66/77; CI: 75.7–92 of ESBL-producing E. coli isolates conferred resistance to beta-lactam and other antimicrobial agents. These results indicate that poultry is a potential reservoir for ESBL-producing Escherichia coli. The presence of ESBL-producing Escherichia coli in poultry destined for human consumption requires strengthening of the antibiotic administering policy. This is important as antibiotic administration in food animals is gaining momentum for improved animal productivity in developing countries such as Zambia.

  3. Epidemiology and virulence of VIM-4 metallo-beta-lactamase-producing Pseudomonas aeruginosa isolated from burn patients in eastern Algeria.

    Science.gov (United States)

    Meradji, Samah; Barguigua, Abouddihaj; Bentakouk, Mohamed Cherif; Nayme, Kaotar; Zerouali, Khalid; Mazouz, Dekhil; Chettibi, Houria; Timinouni, Mohammed

    2016-06-01

    In this study, we investigated the prevalence of carbapenem-resistant Pseudomonas aeruginosa (CRPA) in burn patients from eastern Algeria, CRPA virulence factors and the molecular epidemiology of CRPA. The overall prevalence of CRPA was 48.38%. Seven (46.66%) isolates were metallo-β-lactamases (MBL) producers and contained the MBL genes blaVIM-4 (n=6) and blaVIM-2 (n=1). Risk factors for CRPA infection were urinary catheter use and intubation (p=0.008). A high percentage of virulence factors (86.6% of these isolates were able to produce protease; 73.3% of isolates has DNase; and 66.6% were haemolysin positive) was observed in CRPA isolates. Among the seven MBL-producing isolates, four had the same clonal profile. The class 1 integrons, which contained the aadA7 gene cassette, were detected in six isolates. The 16SrRNA methylase gene, rmtB, was detected in one strain. All CRPA isolates were biofilm formers. A study on the kinetics of biofilm production revealed that biofilm production increased when the concentration of imipenem or ciprofloxacin and the incubation time increased. This is the first study to report the presence of VIM-4-producing P. aeruginosa from North Africa and also of the high prevalence of CRPA isolates. Based on our study of burn unit patients, the high percentage of P. aeruginosa with virulence factors and multi-drug resistance is alarming.

  4. Detection and epidemiology of extended-spectrum beta-lactamases

    NARCIS (Netherlands)

    Platteel, T.N.

    2014-01-01

    The rising prevalence of extended-spectrum beta-lactamase (ESBL-)producing Enterobacteriaceae threatens public health, as treatment options in case of infections are reduced. Rapid detection of carriage or infection of ESBL-producing bacteria is crucial for appropriate infection control measures and

  5. Wild boars as reservoirs of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli of different phylogenetic groups.

    Science.gov (United States)

    Poeta, Patrícia; Radhouani, Hajer; Pinto, Luís; Martinho, António; Rego, Vítor; Rodrigues, Rogério; Gonçalves, Alexandre; Rodrigues, Jorge; Estepa, Vanesa; Torres, Carmen; Igrejas, Gilberto

    2009-12-01

    ESBL-producing E. coli isolates have been isolated from eight of seventy seven faecal samples (10.4%) of wild boars in Portugal. The ESBL types identified by PCR and sequencing were bla(CTX-M-1) (6 isolates) and bla(CTX-M-1) + bla(TEM1-b) (2 isolates). Further resistance genes detected included tet (A) or tet (B) (in three tetracycline-resistant isolates), aad A (in three streptomycin-resistant isolates), cml A (in one chloramphenicol-resistant isolate), sul 1 and/or sul 2 and/or sul 3 (in all sulfonamide-resistant isolates). The intI 1 gene encoding class 1 integrase was detected in all ESBL-producing E. coli isolates. One isolate also carried the intI 2 gene, encoding class 2 integrase. The ESBL-producing E. coli isolates could be assigned to phylogenetic groups B1 (3 isolates), B2 (3 isolates) or A (2 isolates). Amino acid change in GyrA protein (Ser83Leu or Asp87Tyr) was detected in three nalidixic acid-resistant and ciprofloxacin-susceptible isolates. Two amino acid changes in GyrA (Ser83Leu + Asp87Asn) and one in ParC (Ser80Ile) were identified in two nalidixic acid- and ciprofloxacin-resistant isolates. As evidenced by this study wild boars could be a reservoir of antimicrobial resistance genes.

  6. Molecular characterization of extended-spectrum-beta-lactamase-producing Escherichia coli isolates from red foxes in Portugal.

    Science.gov (United States)

    Radhouani, Hajer; Igrejas, Gilberto; Gonçalves, Alexandre; Estepa, Vanesa; Sargo, Roberto; Torres, Carmen; Poeta, Patrícia

    2013-02-01

    The presence of broad-spectrum-cephalosporin-resistant Escherichia coli isolates and the implicated mechanisms of resistance and virulence factor genes were investigated in red fox (Vulpes vulpes) in Portugal. Cefotaxime-resistant E. coli isolates were isolated from two of 52 fecal samples (4 %), being both ESBL producers. The β-lactamase genes found in the two isolates were bla(SHV-12) + bla(TEM-1b). The tet(A) and sul2 genes were also detected in these isolates, together with the non-classical class 1 integron (intI1-dfrA12-orfF-aadA2-cmlA1-aadA1-qacH-IS440-sul3) with the PcH1 promoter. The two isolates belonged to the phylogroup A. Amino acid changes in GyrA (S83L + D87G) and ParC (S80I) proteins were identified in our study. Concerning MLST typing, both isolates were assigned to ST1086, never found before in wild animals, and they presented closely related PFGE patterns. This study reveals the presence of ESBL-producing E. coli isolates, in a wild ecosystem, which could be disseminated through the environment to other niches.

  7. Extended spectrum beta-lactamase-producing Escherichia coli forms filaments as an initial response to cefotaxime treatment

    DEFF Research Database (Denmark)

    Kjeldsen, Thea S. B.; Sommer, Morten Otto Alexander; Olsen, John E.

    2015-01-01

    -producing E. coli to cefotaxime and to determine whether the response depended on the growth phase of the bacterium and the concentration of antibiotic. Results: Two antibiotic resistant strains carrying bla(CTX-M-1) on the chromosome and on an IncI1 plasmid and three sensitive strains were used...... in this study. The resistant strains displayed elongated cells when exposed to cefotaxime at sub-inhibitory as well as therapeutic concentrations (1 to 512 mg/L of cefotaxime) in both lag and early exponential phase, suggesting that the elongation was an initial response mechanism to the antibiotic. Normal...... sized cells were the dominant cell type in exponential and stationary growth phase. No elongated cells were seen in cultures without cefotaxime. In cultures with high concentrations of cefotaxime (128-512 mg/L), no growth other than initial filamentation was observed, but spheroplats appeared after 14...

  8. Epidemiology and Burden of Bloodstream Infections Caused by Extended-Spectrum Beta-Lactamase Producing Enterobacteriaceae in a Pediatric Hospital in Senegal.

    Directory of Open Access Journals (Sweden)

    Awa Ndir

    Full Text Available Severe bacterial infections are not considered as a leading cause of death in young children in sub-Saharan Africa. The worldwide emergence of extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E could change the paradigm, especially in neonates who are at high risk of developing healthcare-associated infections.To evaluate the epidemiology and the burden of ESBL-E bloodstream infections (BSI.A case-case-control study was conducted in patients admitted in a pediatric hospital during two consecutive years. Cases were patients with Enterobacteriaceae BSI and included ESBL-positive (cases 1 and ESBL-negative BSI (cases 2. Controls were patients with no BSI. Multivariate analysis using a stepwise logistic regression was performed to identify risk factors for ESBL acquisition and for fatal outcomes. A multistate model was used to estimate the excess length of hospital stay (LOS attributable to ESBL production while accounting for time of infection. Cox proportional hazards models were performed to assess the independent effect of ESBL-positive and negative BSI on LOS.The incidence rate of ESBL-E BSI was of 1.52 cases/1000 patient-days (95% CI: 1.2-5.6 cases per 1000 patient-days. Multivariate analysis showed that independent risk factors for ESBL-BSI acquisition were related to underlying comorbidities (sickle cell disease OR = 3.1 (95%CI: 2.3-4.9, malnutrition OR = 2.0 (95%CI: 1.7-2.6 and invasive procedures (mechanical ventilation OR = 3.5 (95%CI: 2.7-5.3. Neonates were also identified to be at risk for ESBL-E BSI. Inadequate initial antibiotic therapy was more frequent in ESBL-positive BSI than ESBL-negative BSI (94.2% versus 5.7%, p<0.0001. ESBL-positive BSI was associated with higher case-fatality rate than ESBL-negative BSI (54.8% versus 15.4%, p<0.001. Multistate modelling indicated an excess LOS attributable to ESBL production of 4.3 days. The adjusted end-of-LOS hazard ratio for ESBL-positive BSI was 0.07 (95%CI, 0

  9. Isolation of an NDM-5-producing ST16 Klebsiella pneumoniae from a Dutch patient without travel history abroad, August 2015.

    Science.gov (United States)

    Bathoorn, Erik; Rossen, John W; Lokate, Mariëtte; Friedrich, Alexander W; Hammerum, Anette M

    2015-01-01

    A New Delhi Metallo-beta-lactamase-5 (NDM-5)-producing ST16 Klebsiella pneumoniae strain was isolated from a Dutch patient in a long-term care facility without recent travel history abroad. Core genome multilocus sequence typing (cgMLST) revealed that the Dutch isolate was clonally related to isolates detected in four patients in Denmark in 2014. Public health experts and clinicians need to be informed; repetitive screening may be needed in patients without known risk factors for carbapenemases-producing Enterobacteriaceae who have undergone antibiotic treatment.

  10. A Multicenter Study of Beta-Lactamase Resistant Escherichia coli and Klebsiella pneumoniae Reveals High Level Chromosome Mediated Extended Spectrum β Lactamase Resistance in Ogun State, Nigeria

    Directory of Open Access Journals (Sweden)

    Folasoge A. Adeyankinnu

    2014-01-01

    Full Text Available As a result of the ever increasing problem of multiresistant bacteria, we instituted a surveillance program with the aim of identifying the basic molecular properties of ESBL in our environment. About 197 isolates of Escherichia coli and Klebsiella pneumoniae were selected and tested for ESBL production and antimicrobial susceptibility. Plasmid profiles were determined and curing ability was tested. ESBL prevalence was 26.4% for all isolates tested, with E. coli having a greater proportion. There was absolute resistance to ampicilin, tetracycline, and co-trimaxole among tested isolates. There was above average susceptibility to the 2nd and 3rd generation cephalosporins. Plasmid profiles of tested isolates ranged from 9 kbp to 26 kbp with average of 14.99±2.3 kbp for E. coli and 20.98±1.8 kbp K. pneumoniae, 9.6% of ESBL positive E. coli plasmids were cured, while 3.9% of K. pneumoniae plasmids were cured after treatment. The present study shows an upsurge in ESBL acquisition by gram negative bacteria and evidence of cocirculation of varying subtypes of ESBL with both plasmid transmissible and chromosome encoded subtypes. This calls for universal surveillance and more effort towards molecular epidemiology of this public health treatment.

  11. Interactions of ceftobiprole with beta-lactamases from molecular classes A to D.

    Science.gov (United States)

    Queenan, Anne Marie; Shang, Wenchi; Kania, Malgosia; Page, Malcolm G P; Bush, Karen

    2007-09-01

    The interactions of ceftobiprole with purified beta-lactamases from molecular classes A, B, C, and D were determined and compared with those of benzylpenicillin, cephaloridine, cefepime, and ceftazidime. Enzymes were selected from functional groups 1, 2a, 2b, 2be, 2d, 2e, and 3 to represent beta-lactamases from organisms within the antibacterial spectrum of ceftobiprole. Ceftobiprole was refractory to hydrolysis by the common staphylococcal PC1 beta-lactamase, the class A TEM-1 beta-lactamase, and the class C AmpC beta-lactamase but was labile to hydrolysis by class B, class D, and class A extended-spectrum beta-lactamases. Cefepime and ceftazidime followed similar patterns. In most cases, the hydrolytic stability of a substrate correlated with the MIC for the producing organism. Ceftobiprole and cefepime generally had lower MICs than ceftazidime for AmpC-producing organisms, particularly AmpC-overexpressing Enterobacter cloacae organisms. However, all three cephalosporins were hydrolyzed very slowly by AmpC cephalosporinases, suggesting that factors other than beta-lactamase stability contribute to lower ceftobiprole and cefepime MICs against many members of the family Enterobacteriaceae.

  12. [blaVIM-2 gene detection in metallo-beta-lactamase-producing Pseudomonas aeruginosa strains isolated in an intensive care unit in Ciudad Bolívar, Venezuela].

    Science.gov (United States)

    Guevara, Armando; de Waard, Jacobus; Araque, María

    2009-08-01

    Ten Pseudomonas aeruginosa strains with resistance to broad-spectrum cephalosporin and carbapenems were studied to determine the presence of genes that mediate the production of metallo-beta-lactamases. These strains were isolated from patients with nosocomial infection at the Intensive Care Unit of the Complejo Hospitalario "Ruiz y Paéz" of Ciudad Bolívar, Bolívar State, Venezuela, from 2003 to 2006. In all isolates a metallo-enzyme activity was detected by using the double disk synergism test. PCR amplification of genes encoding the families IMP, VIM and SPM metallo-beta-lactamases showed the presence of a blaVIM gene in all strains studied. DNA sequencing revealed that all isolates showed the presence of blaVIM-2. These results suggest that it is necessary to keep these strains under epidemiologic surveillance, establish laboratory strategies for opportune detection and the implementation of new policies to ensure the appropriate use of antibiotics in this institution.

  13. Improved detection of extended spectrum beta-lactamase (ESBL)-producing Escherichia coli in input and output samples of German biogas plants by a selective pre-enrichment procedure.

    Science.gov (United States)

    Schauss, Thorsten; Glaeser, Stefanie P; Gütschow, Alexandra; Dott, Wolfgang; Kämpfer, Peter

    2015-01-01

    The presence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was investigated in input (manure from livestock husbandry) and output samples of six German biogas plants in 2012 (one sampling per biogas plant) and two German biogas plants investigated in an annual cycle four times in 2013/2014. ESBL-producing Escherichia coli were cultured by direct plating on CHROMagar ESBL from input samples in the range of 100 to 104 colony forming units (CFU) per g dry weight but not from output sample. This initially indicated a complete elimination of ESBL-producing E. coli by the biogas plant process. Detected non target bacteria were assigned to the genera Acinetobacter, Pseudomonas, Bordetella, Achromobacter, Castellaniella, and Ochrobactrum. A selective pre-enrichment procedure increased the detection efficiency of ESBL-producing E. coli in input samples and enabled the detection in five of eight analyzed output samples. In total 119 ESBL-producing E. coli were isolated from input and 46 from output samples. Most of the E. coli isolates carried CTX-M-type and/or TEM-type beta lactamases (94%), few SHV-type beta lactamase (6%). Sixty-four blaCTX-M genes were characterized more detailed and assigned mainly to CTX-M-groups 1 (85%) and 9 (13%), and one to group 2. Phylogenetic grouping of 80 E. coli isolates showed that most were assigned to group A (71%) and B1 (27%), only one to group D (2%). Genomic fingerprinting and multilocus sequence typing (MLST) showed a high clonal diversity with 41 BOX-types and 19 ST-types. The two most common ST-types were ST410 and ST1210. Antimicrobial susceptibility testing of 46 selected ESBL-producing E. coli revealed that several isolates were additionally resistant to other veterinary relevant antibiotics and some grew on CHROMagar STEC but shiga-like toxine (SLT) genes were not detected. Resistance to carbapenems was not detected. In summary the study showed for the first time the presence of ESBL-producing E. coli in

  14. Improved detection of extended spectrum beta-lactamase (ESBL-producing Escherichia coli in input and output samples of German biogas plants by a selective pre-enrichment procedure.

    Directory of Open Access Journals (Sweden)

    Thorsten Schauss

    Full Text Available The presence of extended-spectrum beta-lactamase (ESBL-producing Escherichia coli was investigated in input (manure from livestock husbandry and output samples of six German biogas plants in 2012 (one sampling per biogas plant and two German biogas plants investigated in an annual cycle four times in 2013/2014. ESBL-producing Escherichia coli were cultured by direct plating on CHROMagar ESBL from input samples in the range of 100 to 104 colony forming units (CFU per g dry weight but not from output sample. This initially indicated a complete elimination of ESBL-producing E. coli by the biogas plant process. Detected non target bacteria were assigned to the genera Acinetobacter, Pseudomonas, Bordetella, Achromobacter, Castellaniella, and Ochrobactrum. A selective pre-enrichment procedure increased the detection efficiency of ESBL-producing E. coli in input samples and enabled the detection in five of eight analyzed output samples. In total 119 ESBL-producing E. coli were isolated from input and 46 from output samples. Most of the E. coli isolates carried CTX-M-type and/or TEM-type beta lactamases (94%, few SHV-type beta lactamase (6%. Sixty-four blaCTX-M genes were characterized more detailed and assigned mainly to CTX-M-groups 1 (85% and 9 (13%, and one to group 2. Phylogenetic grouping of 80 E. coli isolates showed that most were assigned to group A (71% and B1 (27%, only one to group D (2%. Genomic fingerprinting and multilocus sequence typing (MLST showed a high clonal diversity with 41 BOX-types and 19 ST-types. The two most common ST-types were ST410 and ST1210. Antimicrobial susceptibility testing of 46 selected ESBL-producing E. coli revealed that several isolates were additionally resistant to other veterinary relevant antibiotics and some grew on CHROMagar STEC but shiga-like toxine (SLT genes were not detected. Resistance to carbapenems was not detected. In summary the study showed for the first time the presence of ESBL-producing E

  15. Correlation between beta-lactamase production and MIC values against penicillin with coagulase negative staphylococci.

    Directory of Open Access Journals (Sweden)

    Narayani T

    1989-07-01

    Full Text Available Two hundred strains of coagulase negative staphylococci (CNS isolated from various clinical specimens (116 and healthy hospital personnel (84 were investigated for the production of beta-lactamases by means of three iodometric techniques and correlated with the minimum inhibitory concentration (MIC values of penicillin-G by agar dilution technique and disc diffusion technique. One hundred and fifty (75.0% of the 200 strains tested produced beta-lactamases. Seventy two per cent of the CNS were found to be beta-lactamase positive by the starch paper technique which was the most sensitive one in our study. The MIC values of penicillin against CNS ranged from less than or equal to 1.25 to greater than or equal to 2000 units. The present study indicated the higher prevalence of beta-lactamase producers with increased penicillin resistance among CNS strains isolated from healthy carriers and hospitalised patients.

  16. Métodos alternativos para detecção de betalactamase de espectro estendido em Escherichia coli e Klebsiella pneumoniae Alternative methods for the detection of extended-spectrum-beta-lactamase in Escherichia coli and Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    Alexsander Costa Martins

    2011-08-01

    Full Text Available INTRODUÇÃO: A resistência a antimicrobianos tem aumentado rapidamente nos últimos anos no Brasil e no mundo e, embora exista uma variedade de mecanismos de resistência, destaca-se a produção de betalactamase de espectro estendido (ESBL como um dos principais. Essas enzimas são mediadas por plasmídios, conferem resistência a vários antimicrobianos betalactâmicos e são inibidas por compostos, como ácido clavulânico, sulbactam e tazobactam. OBJETIVO: O objetivo deste estudo foi comparar metodologias alternativas à técnica padrão preconizada pelo Clinical and Laboratory Standards Institute (CLSI para detecção de ESBL. MATERIAL E MÉTODO: Foram realizados testes com 36 isolados (26 de E. coli e 10 de K. pneumoniae mediante disco combinado (CLSI e técnicas alternativas designadas meio disco (MD e substituição de discos (SD. CONCLUSÃO: As duas metodologias propostas apresentaram resultados satisfatórios com sensibilidade superior a 90% e custo inferior à técnica de referência (disco combinado, podendo ser utilizadas na pesquisa de ESBL.INTRODUCTION: Antimicrobial resistance has increased apace in Brazil and worldwide in the last years, even though there is a great variety of resistance mechanisms and extended spectrum beta-lactamases (ESBL is among the main ones. These enzymes are plasmid mediated, which causes resistance to some beta-lactam antimicrobials and are inhibited by compounds such as clavulanic acid, sulbactam and tazobactam. OBJECTIVE: The objective of this study was to compare alternative methods to the standard ESBL detection technique recommended by the Clinical and Laboratory Standards Institute (CLSI. MATERIAL AND METHOD: Tests with 36 isolates (26 E. coli and 10 K. pneumoniae were performed by means of CLSI disk diffusion method and alternative techniques designated as half disk (HD and disk substitution (SD. CONCLUSION: Both methods yielded satisfactory results with higher sensitivity (90% and lower costs

  17. Beta-lactamase Escherichia coli and Staphylococcus aureus isolated from chickens in Nigeria

    Directory of Open Access Journals (Sweden)

    Godwin Onyemaechi Egwu

    2010-06-01

    Full Text Available The occurrence of beta-lactamase-producing Escherichia coli and Staphylococcus aureus in chickens was investigated. Specimens (n = 1 300 were collected from 400 chickens and were streaked on MacConkey agar plates. From each plate, presumptive growths of organisms were picked and streaked on eosin methylene blue and Baird-Parker agars, respectively. Typical colonies of E. coli and S. aureus with similar morphologies were identified by biochemical tests. Isolates were tested for beta-lactamase production and antimicrobial susceptibilities. Results indicated that 805 E. coli isolates from which 89 (11% were beta-lactamase-positive and 660 S. aureus from which 58 (8.8% were beta-lactamase-positive. Both isolates showed a high level of resistance to all twelve antibiotics screened. The increased prevalence of antibiotic resistance amongst bacterial organisms is undoubtedly correlated with the discovery and characterisation of multiple, transferrable resistance determinants, such as beta-lactamases, corresponding to their respective phenotypes. The implications of this for humans when handling and/or consuming chickens and chicken products contaminated with strains of such isolates, is a risk of transferrable multi-drug resistance and a failure of treatment. The results of our study indicated that beta-lactamase-producing E. coli and S. aureus are prevalent in chickens in Nigeria.

  18. Community-acquired urinary tract infections by extended-spectrum beta-lactamase-producing Enterobacteriaceae in Zenica-Doboj Canton, Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    D. Saric

    2006-08-01

    Full Text Available The aim of this study was to determine the incidence and antimicrobial resistance of ESBL-producing strains in the community-acquired urinary tract infections (CAUTIs, which is necessary for antimicrobial therapy selection. From January 2003 to September 2004, 4,112 consecutive, non-duplicate coliform isolates from CAUTIs were analyzed. Antimicrobial susceptibility testing to fifteen antimicrobials was performed by disc-diffusion method. Double-disk synergy test (DDST with amoxicillin-clavulanat, cefotaxime, ceftazidime, ceftriaxone and aztreonam, and Etest strips with PM/PML (AB Biodisk was performed according to CLSI recommendation in order to detect the ESBL producers. The overall incidence of ESBL producing strains was 2.6% (108/4112, it was significantly higher in males, 8.4% (79/936 than in females, 0.9% (29/3176. The highest prevalence of ESBL producers was noted in the oldest and youngest age group: 4.8% (52/106 and 2.6% (27/1045, respectively. An increase from 2.2% (52/2402 to 3.3% (56/1710, and a shift of ESBL producers toward the age group 0-6 years (1.6% and 3.8%, respectively in this period was observed. The incidence of ESBL producing strains among isolated Klebsiella spp. were 7.8% (83/1060, E. coli 0.7% (18/2561, Citrobacter spp. 0.6% (1/156, Enterobacter spp. 7.7% (3/39 and Proteus spp. 1.0% ( 3/297. Among ESBL producing isolates Klebsiella spp. predominated, 76.9% (83/108, followed by E. coli 16.7% (18/108. ESBL producing strains showed significantly higher resistance rates to all tested antibiotics as compared to to non-ESBL-producers. The increase and shift toward the youngest age group of the ESBL producer incidences is of our concern. Further studies are required to detect ESBL types in terms of highly different geographical dissemination of these isolates.

  19. [Extended-spectrum-beta-lactamase-producing Proteus mirabilis: laboratory-based surveillance in cooperation with 12 clinical laboratories in the Kinki Region of Japan].

    Science.gov (United States)

    Nakamura, Tatsuya; Komatsu, Masaru; Shimakawa, Kouichi; Sueyoshi, Noriyuki; Satoh, Kaori; Toyokawa, Masahiro; Nishio, Hisaaki; Wada, Yasunao; Orita, Tamaki; Kofuku, Tomomi; Sakamoto, Masako; Okamoto, Kiyotaka; Akagi, Masahiro; Kinoshita, Shohiro

    2006-05-01

    We studied 247 strains of Proteus mirabilis collected during the 6 months from November 2003 to April 2004 from 12 clinical laboratories in the Kinki region of Japan for the production of extended-spectrum beta-lactamase (ESBL). Eighteen strains (7.3%) showed MICs for cefpodoxime of > or = 2 microg/mL and 13 strains (5.2%) were positive for the double-disk synergy test. Susceptibility depended on genotype. MICs for cefepime, cefozopran, and cefpirome were high (> or = 8 microg/mL), and that for ceftazidime was low (0.12-0.5 microg/mL). Meropenem showed the lowest MIC (ESBL genotype by the polymerase chain reaction showed that 12 of 13 strains were CTX-M2 types. CTX-M9 was detected in a single laboratory. The clinical background showed 5 strains in urine samples. Twelve of 13 strains were detected in patients with minimal devices use. No symptoms were found in most cases of established syndrome. Analysis of PCR fingerprint profiles of random amplified polymorphic DNA patterns showed that 6 of 7 strains from hospital 1 showed the same pattern, and 5 of 5 strains from hospital 13 showed the same pattern, suggesting the nosocomial spread of P. mirabilis in each hospital.

  20. Production of CTX-M-3 extended-spectrum beta-lactamase and IMP-1 metallo beta-lactamase by five Gram-negative bacilli: survey of clinical isolates from seven laboratories collected in 1998 and 2000, in the Kinki region of Japan.

    Science.gov (United States)

    Yamasaki, Katsutoshi; Komatsu, Masaru; Yamashita, Tomonari; Shimakawa, Koichi; Ura, Toshiro; Nishio, Hisaaki; Satoh, Kaori; Washidu, Ryoudou; Kinoshita, Shohiro; Aihara, Masanori

    2003-03-01

    The aim of this study was to research the distribution in the Kinki region of Japan of Enterobacteriaceae and Pseudomonas aeruginosa that produce extended-spectrum beta-lactamase (ESBL) and metallo beta-lactamase (MBL). One thousand isolates, 200 of each of four enterobacterial species (i.e. Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Serratia marcescens) and 200 of P. aeruginosa, were collected from seven different laboratories during two 2 month periods, one in 1998 and one in 2000. A double-disc synergy test (DDST) and 2-mercaptopropionic acid inhibition test (2-MPAT) were used to confirm beta-lactamase-producing isolates. The DDST was positive for one isolate of E. coli, five of K. pneumoniae, two of E. cloacae and 14 of S. marcescens. The 2-MPAT was positive for five isolates of S. marcescens and two of P. aeruginosa. We identified the beta-lactamase type of each isolate by molecular confirmatory tests (isoelectric focusing, PCR and DNA sequencing): CTX-M-3 ESBLs (three isolates of K. pneumoniae, two of E. cloacae and 13 of S. marcescens), CTX-M-2 ESBL (one isolate of K. pneumoniae), SHV-12 ESBLs (one isolate of E. coli and one of S. marcescens), CTX-M-3 and SHV-12 combination ESBL (one isolate of K. pneumoniae) and IMP-1 MBLs (five isolates of S. marcescens and two of P. aeruginosa). In conclusion, many species of Gram-negative bacilli that produce CTX-M-3 ESBLs and IMP-1 MBLs were disseminated widely in different hospitals of the Kinki region of Japan. Therefore, monitoring of laboratory bacterial ecology seems important to stop the spread of these strains through nosocomial outbreaks.

  1. Induction of beta-lactamase production in Pseudomonas aeruginosa biofilm

    DEFF Research Database (Denmark)

    Giwercman, B; Jensen, E T; Høiby, N;

    1991-01-01

    Imipenem induced high levels of beta-lactamase production in Pseudomonas aeruginosa biofilms. Piperacillin also induced beta-lactamase production in these biofilms but to a lesser degree. The combination of beta-lactamase production with other protective properties of the biofilm mode of growth...

  2. Multiple Renal Abscesses due to ESBL Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Causing Acute Pyelonephritis and Bacteremia: A Case Report with a Good Outcome (No Drainage Required)

    Science.gov (United States)

    Qurash, Musaad; Saleh, Asem; Ali, Rasha

    2016-01-01

    Extended-spectrum beta-lactamase-producing Enterobacteriaceae urinary tract infections are challenging infections with increased mortality, morbidity, and failure of therapy. A 44-year-old Saudi male diabetic patient was seen at the ER of IMC Hospital with features of acute pyelonephritis: fever, burning urine, and left flank pain for three days. He was treated for cystitis at the Endocrine Clinic two weeks prior to his ER visit with nitrofurantoin and levofloxacin orally according to urine culture and sensitivity result. The patient was admitted, received IV meropenem, and continued to be febrile for three days. His urine and blood culture at ER grew the same ESBL-producing E. coli as in his urine culture from the Endocrine Clinic. His abdomen CT scan showed two left renal abscesses at the upper and middle poles. His temperature resolved on the fourth day of IV therapy. Intravenous meropenem was continued for 4 weeks after inserting PICC line and the patient was followed up by home healthcare. He was feeling better with occasional left flank pain and repeated abdomen CT scan showed complete resolution of both renal abscesses. PMID:28018690

  3. Detection of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in vegetables, soil and water of the farm environment in Tunisia.

    Science.gov (United States)

    Ben Said, Leila; Jouini, Ahlem; Klibi, Naouel; Dziri, Raoudha; Alonso, Carla Andrea; Boudabous, Abdellatif; Ben Slama, Karim; Torres, Carmen

    2015-06-16

    One-hundred-nine samples of 18 different farms (49 of food-vegetables, 41 of soil and 19 of irrigation water) and 45 vegetable food samples of 13 markets were collected in Tunisia. These samples were inoculated in MacConkey agar plates supplemented with cefotaxime (2 μg/ml). ESBL-producing Enterobacteriaceae (ESBL-Eb) were detected in 10 of the 109 farm samples (vegetables, 8.2%; soil, 7.3%; water, 15.8%), and in 4 of 45 vegetables of markets (8.9%), recovering 15 ESBL-Eb. Isolates and ESBL genes detected were: Escherichia coli (n=8: 5 blaCTX-M-1, 2 blaCTX-M-15 and one blaCTX-M-14), Citrobacter freundii (n=4: 3 blaCTX-M-15 and one blaSHV-12), Enterobacter hormaechei (n=2: 2 blaCTX-M-15) and Klebsiella pneumoniae (n=1, blaCTX-M-15). The ISEcp1 sequence was found upstream of blaCTX-M genes in 13 of 14 strains (in three cases truncated by IS5), and orf477 or IS903 downstream. Class 1 integrons were detected in five strains and contained two gene cassette arrangements (dfrA17-aadA5 and aadA1). Most isolates tested showed a multiresistant phenotype. All blaCTX-M-15-positive strains carried the aac(6')-1b-cr gene, that affects to amikacin-tobramycin-kanamycin-ciprofloxacin. Five ESBL-Eb strains carried genes of the qnr family. The 8 ESBL-positive E. coli isolates were typed as: ST58/B1 (n=3) and ST117/D, ST131/B2, ST10/A, ST23/A, and the new ST3496/D (one strain, each). From 1-2 plasmids were detected in all ESBL-positive E. coli isolates (63-179 kb). The ESBL genes were transferred by conjugation in 4 blaCTX-M-1-positive E. coli strains, and transconjugants acquired a 97 kb IncI1 plasmid. ESBL-Eb isolates are frequently disseminated in vegetable farms and potentially could be transmitted to humans through the food chain.

  4. PREVALENCE OF EXTENDED SPECTRUM Β-LACTAMASE (ESBL PRODUCING ESCHERICHIA COLI AND KLEBSIELLA ISOLATED FROM VARIOUS IN PATIENT DEPARTMENT SAMPLES

    Directory of Open Access Journals (Sweden)

    Dasgupta Rubin

    2012-05-01

    Full Text Available The present study was focused to isolate ESBL (Extended Spectrum Beta Lactamase producing Escherichia coli and Klebseilla sp. from the IPD (In Patient Department and to determine the resistant profile of ESBL producers . The tests were carried out with the help of Double Disk Approximation test and Vitek ESBL test. About 70.4% of the E.coli isolates showed the ESBL positive while about 86.1% of the Klebsiella sp. showed positive result. The antibiotics against which the bacteria’s showed the maximum resistant are Penicillin, Fluoroquinolones, Cephalosporins and Monobactum, which was 100%. The least resistant was shown against Lepopeptides. Knowledge of resistance pattern of bacterial strains in geographical areas will help to guide the appropriate and judicious antibiotic use. While comparing the result of this study with the previous studies it was concluded that the rates of ESBL positive strain vary greatly worldwide and within geographic areas and are rapidly changing overtime.

  5. Distribution of CTX-M group I and group III β-lactamases produced by Escherichia coli and klebsiella pneumoniae in Lahore, Pakistan.

    Science.gov (United States)

    Abrar, Samyyia; Vajeeha, Ayesha; Ul-Ain, Noor; Riaz, Saba

    2017-02-01

    Extended-spectrum-lactamases (ESBLs) of the CTX-M type is worrisome issue in many countries of the world from past decade. But little is known about CTX-M beta-lactamase producing bacteria in Pakistan. Therefore, this study was carried out to investigate the distribution of CTX-M beta-lactamase producing E. coli and Klebsiella pneumoniae using phenotypic and molecular techniques. A total of 638 E. coli and 338 Klebsiella pneumoniae were isolated from patients attending two hospitals and one diagnostic Centre in Pakistan during 2013-2015. ESBL production was screened by double disc synergism, combination disc (cefotaxime and ceftazidime with clavulanic acid) and E-test. These strains were further characterized by PCR (CTX-M I, CTX-M III) and sequencing. After ribotyping of strains accession numbers were obtained. These isolates were highly resistant to cephalosporins, ceftazidime, cefotaxime, aztreonam, and cefuroxime but susceptible to carbapenems, sulfzone, amikacin and tazocin. Multiple antibiotic resistances index (MAR) revealed that 51% of E. coli strains fell in the range of 0.61-0.7 and 39% of Klebsiella pneumoniae strains fell in the range of 0.71-0.8. 64% Double disc synergism (DDS), 76.4% combination disc (CD), 74% E-test showed ESBL positivity in strains. In E. coli ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 212 (72.1%) and 25 (8.5%) respectively. In Klebsiella pneumoniae ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 89 (82.4%) and 10 (9.2%). Combination of both genes blaCTX-M-I and blaCTX-M-III were found in 16 (5.4%) of E. coli strains and 5 (4.6%) of Klebsiella pneumoniae strains. Sequencing revealed that CTXM-15 was predominately present in the CTX-M-I group. The prevalence of ESBL producing E. coli and Klebsiella pneumoniae isolates was high and the majority of them positive for blaCTX-M-I as compared to blaCTX-M-III. These findings highlight the need to further investigate the epidemiology of other CTX-M beta-lactamases

  6. The Class Antibiotic Cross Allergic Reaction Correlation Studies of 120 Cases of Patients Who Use Beta-lactamase-producing%120例患者使用β-内酰胺类抗生素交叉过敏反应相关性的研究

    Institute of Scientific and Technical Information of China (English)

    张洁; 欧阳爱军; 王鹏

    2012-01-01

      目的通过对各类β-内酰胺类药物相互交叉过敏反应相关性研究,找寻各类β-内酰胺类药物相互交叉过敏反应比率。为临床合理选择β-内酰胺类药物提供理论依据。方法通过对在2011年3月至5月期间住院的有β-内酰胺类抗生素过敏患者进行调查,对结果进行回顾性统计分析。结果青霉素与头孢类抗生素发生交叉过敏的的概率较低;头孢类抗生素与其他β-内酰胺类药物相互交叉过敏反应的概率相对较高。结论对于有青霉素过敏的患者且头孢皮试阴性的患者,使用头孢类抗生素是安全的。%  Objective Though the correlation studies of all kinds of beta beta-lactamase-producing drugs overlapping allergic reaction, to find all kinds of beta beta-lactamase-producing drugs overlapping allergic reaction ratio. For clinical rational choice beta beta-lactamase-producing provide theoretical basis of drugs. Methods Based on the march in 2011 to five months in the hospital there are beta beta-lactamase-producing class antibiotic allergy patients to survey, statistics and analysis results. Results With cephalosporin antibiotic penicillin allergies to the probability of happened cross low; Cephalosporin antibiotic and other beta beta-lactamase-producing drugs overlapping the probability of an allergic reaction are relatively high. Conclusion Patients with penicillin allergies and skin test negatie patient cephalosporins, use cephalosporin antibiotic is safe.

  7. Characterization of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients in the Zagreb region

    Directory of Open Access Journals (Sweden)

    Branka Bedenić,

    2010-02-01

    Full Text Available Aim To determine the prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients during a three-year period, to determine their antibiotic susceptibility, investigate the transfer of ESBL genes with cotransfer of resistance and to characterize isolated beta-lactamases. Methods Antimicrobial susceptibility was determined by disk diffusion and broth microdilution methods. The double-disk test was used for ESBL detection. Transfer of resistance was performed by broth mating method and characterization of isolated beta-lactamases by polymerase chain reaction. Results The prevalence of ESBL-producing E. coli was 1.5% and of K. pneumoniae 4.1% with its different distribution according to patients`age and gender. ESBL-producing K. pneumoniae showed high resistance rates to aminoglycosides, cotrimoxazole, nitrofurantoin and quinolones while ESBL-producing E. coli isolates, with exception of high aminoglycoside resistance, showed low resistance rates to other antibiotics. Successful conjugation of ESBL genes was obtained with 25% E. coli and 76.2% K. pneumoniae strains. Comparing to E. coli, K. pneumoniae strains showed higher rates of aminoglycosideand cotrimoxazole resistance cotransfer. Beta-lactamases of investigated strains belonged to TEM, SHV and CTX-M families.Conclusion The existence of multiple-resistant ESBL-producing E. coli and K. pneumoniae strains was confirmed in observed outpatient population. ESBL-producing K. pneumoniae isolates, in contrast toESBL-producing E. coli, showed higher resistance rates to non-beta-lactam antibiotics, probably caused by cotransfer of resistance genes located on the same plasmid as ESBL genes. It is important to monitor the prevalence of such strains and their possible spreading in the outpatient population of the Zagreb region

  8. Combined disc methods for the detection of KPC- and/or VIM-positive Klebsiella pneumoniae: improving reliability for the double carbapenemase producers.

    Science.gov (United States)

    Miriagou, V; Tzelepi, E; Kotsakis, S D; Daikos, G L; Bou Casals, J; Tzouvelekis, L S

    2013-09-01

    Klebsiella pneumoniae strains co-producing klebsiella pneumoniae carbapenemase (KPC) and verona integron-encoded metallo-beta-lactamase (VIM) are frequently isolated in Greece and have also occurred in other European countries. Conventional combined disc tests exhibit low sensitivity against these emerging pathogens. We have evaluated modifications of the KPC/Metallo-β-Lactamase Confirmation kit (ROSCO) exhibiting high diagnostic value against KPC, VIM and KPC + VIM producers. The key changes were the inclusion of additional combined tablets containing meropenem plus two inhibitors (dipicolinic acid (1000 μg per tablet) for metallo-β-lactamases and a boronic acid derivative for KPCs) and the replacement of aminophenylboronic acid by phenylboronic acid (400 μg per tablet).

  9. Antibodies against beta-lactamase can improve ceftazidime treatment of lung infection with beta-lactam-resistant Pseudomonas aeruginosa in a rat model of chronic lung infection

    DEFF Research Database (Denmark)

    Ciofu, Oana; Bagge, Niels; Høiby, Niels

    2002-01-01

    To test the hypothesis that antibodies against the chromosomal beta-lactamase of Pseudomonas aeruginosa (a beta ab) might act as beta-lactamase inhibitors in patients with cystic fibrosis and chronic lung infection with P. aeruginosa, we compared in a rat model of chronic lung infection...... the efficacy of treatment with ceftazidime in beta-lactamase-immunized (group I) and non-immunized (group II) rats. Chronic lung infection was established with alginate-embedded P. aeruginosa producing high amounts of beta-lactamase in 133 Lewis rats. Prior to infection, group I (66 rats) was immunized three...... times at 2-week intervals with purified beta-lactamase in incomplete Freund's adjuvant (IFA) and group II (67 rats) received IFA. Ceftazidime treatment was initiated after challenge and continued for 10 days, after which the rats were sacrificed and the lung bacteriology and pathology were analysed. Rat...

  10. Genome Sequence of Klebsiella pneumoniae Bacteriophage PMBT1 Isolated from Raw Sewage

    Science.gov (United States)

    Brinks, Erik; Fiedler, Gregor; Hüsing, Christina; Cho, Gyu-Sung; Hoeppner, Marc P.; Heller, Knut J.; Neve, Horst; Franz, Charles M. A. P.

    2017-01-01

    ABSTRACT A bacteriophage virulent for extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae strain 182 was isolated from sewage. The double-stranded DNA (dsDNA) genome showed high similarity to the genomes of other Klebsiella pneumoniae phages. It comprises 175,206 bp with a mol% G+C content of 41.9 and contains 276 putative open reading frames (ORFs) and one tRNA. PMID:28232430

  11. Prolonged colonisation with Escherichia coli O25:ST131 versus other extended-spectrum beta-lactamase-producing E. coli in a long-term care facility with high endemic level of rectal colonisation, the Netherlands, 2013 to 2014.

    Science.gov (United States)

    Overdevest, Ilse; Haverkate, Manon; Veenemans, Jacobien; Hendriks, Yvonne; Verhulst, Carlo; Mulders, Ans; Couprie, Willemijn; Bootsma, Martin; Johnson, James; Kluytmans, Jan

    2016-10-20

    The extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clone ST131 (ESBL-ST131) has spread in healthcare settings worldwide. The reasons for its successful spread are unknown, but might include more effective transmission and/or longer persistence. We evaluated the colonisation dynamics of ESBL-producing E. coli (ESBL-EC), including ESBL-ST131, in a long-term care facility (LTCF) with an unusually high prevalence of rectal ESBL-EC colonisation. During a 14-month period, rectal or faecal samples were obtained from 296 residents during six repetitive prevalence surveys, using ESBL-selective culture. Transmission rates, reproduction numbers, and durations of colonisation were compared for ESBL-ST131 vs other ESBL-EC. Furthermore, the likely time required for ESBL-ST131 to disappear from the LTCF was estimated. Over time, the endemic level of ESBL-ST131 remained elevated whereas other ESBL-EC returned to low-level prevalence, despite comparable transmission rates. Survival analysis showed a half-life of 13 months for ESBL-ST131 carriage, vs two to three months for other ESBL-EC (p < 0.001). Per-admission reproduction numbers were 0.66 for ESBL-ST131 vs 0.56 for other ESBL-EC, predicting a mean time of three to four years for ESBL-ST131 to disappear from the LTCF under current conditions. Transmission rates were comparable for ESBL-ST131 vs other ESBL-EC. Prolonged rectal carriage explained the persistence of ESBL-ST131 in the LTCF.

  12. Detection of extended spectrum beta-lactamases in gram negative bacilli from clinical specimens in a teaching hospital in South eastern Nigeria

    Directory of Open Access Journals (Sweden)

    C N Akujobi

    2010-01-01

    Full Text Available Antimicrobial drug resistance seen among many gram-negative bacteria, especially those expressing the extended-spectrum β- lactamase (ESBL enzymes that hydrolyze the expanded- spectrum cephalosporins has been on the increase. This has compromised treatment options and thus a threat to the containment of bacterial infections. To determine the existence of the extended-spectrum β-lactamase enzymes in Nnewi, 250 clinical isolates of members of the family Enterobacteriaceae and Pseudomonas species from Nnamdi Azikiwe University Teaching Hospital, Nnewi were identified by conventional methods. These include Klebsiella species (96, E. coli (90, Pseudomonas species (37, Enterobacter species (13, Proteus species (6, Citrobacter species (5 and Salmonella species (3. Antimicrobial drug susceptibility testing was carried out on all the isolates by the disc diffusion method. Extended Spectrum Beta- lactamases were detected by the double disc synergy test. High level of antimicrobial resistance was noted in test organisms against some of the antimicrobial drugs: Ampicillin + Cloxacillin (93.2%, Tetracycline (90.8%, Streptomycin (82.4%, and Nalidixic acid (62%, and low level of resistance was observed against Ofloxacin (26.4%, Cefotaxime (28.8% and Nitrofurantoin (28.8%. One hundred and forty four isolates (57.6% were suspected ESBL-producers judged by their resistance to any of the third generation cephalosporins used but 40 (16% actually produced the extended spectrum beta- lactamase enzymes. This shows the existence of Extended Spectrum Beta- Lactamase producing gram negative organisms in Nnewi. Considering the treatment difficulties, as well as the high cost of treatment associated with these organisms, concerted efforts are needed to contain their spread.

  13. 耐碳青霉烯类药物肺炎克雷伯菌β-内酰胺酶与膜孔蛋白编码基因以及KPC-ISKpn6连锁检测%Detection of beta-lactamase, porin-coding genes and linkage of KPC-ISKpn6 of the carbapenems-resistant Klebsiella pneumoniae

    Institute of Scientific and Technical Information of China (English)

    崔进; 冯旰珠; 王良梅; 赵水娣; 张扬; 高天明

    2012-01-01

    目的 探讨耐碳青霉烯类药物肺炎克雷伯菌的耐药机制.方法 对南京地区两家三甲综合性医院的耐碳青霉烯抗菌药物肺炎克雷伯菌临床分离株,采用PCR方法对其40种β-内酰胺酶基因、膜孔蛋白编码基因及KPC-ISKpn6连锁进行检测,PCR阳性产物进行测序,测序结果BLAST对比分析.结果 24株耐碳青霉烯类药物肺炎克雷伯菌的A类β-内酰胺酶编码基因TEM-1及SHV的阳性检出率为100% (24/24)、KPC-2的阳性检出率为95.8% (23/24)、LAP-2的阳性检出率为45.8% (11/24),C类β-内酰胺酶编码基因DHA的阳性检出率为4.2% (1/24),KPC-ISKpn6连锁检测阳性率为95.8% (23/24),膜孔蛋白编码基因ompK35与ompK36的突变率分别为95.8% (23/24)及100%(24/24).结论 本组肺炎克雷伯菌β-内酰胺酶TEM-1、SHV、KPC-2、LAP-2的携带率较高,其中KPC-2的高携带率及膜孔蛋白编码基因ompK35、ompK36的高突变率是本组肺炎克雷伯菌对碳青霉烯类抗菌药物耐药的主要机制;插入序列ISKpn6可能参与了KPC-2基因的介导.%Objective To investigate the resistance-mechanism of the carbapenems-resistant Klebsiella pneumoniae isolated from clinical.Methods The clinical isolates of carbapenems-resistant Klebsiella pneumoniae from top three comprehensive hospitals of Nanjing area were examined by 40 beta-lactamase,porin-coding genes and linkage of KPC-ISKpn6 using PCR method,the PCR positive results were picked out for sequencing and sequencing BLAST search for comparison analysis.Results Twenty-four strains of carbapenems-resistant Klebsiella pneumoniae were detected,the positive rate of A beta-lactamase TEM-1 and SHV was 100% (24/24),KPC-2 and LAP-2 was 95.8% (23/24),45.8% (11/24) respectively,and C beta-lactamase DHA was 4.2% (1/24).Meanwhile,the positive detection rates of KPC-ISKpn6 linkage was 95.8% (23/24),and the mutation rate of porin-coding genes ompK35 and ompK36 were up to 95.8% (23/24) and 100

  14. Clonal dissemination of multilocus sequence type ST15 KPC-2-producing Klebsiella pneumoniae in Bulgaria.

    Science.gov (United States)

    Markovska, Rumyana; Stoeva, Temenuga; Schneider, Ines; Boyanova, Lyudmila; Popova, Valentina; Dacheva, Daniela; Kaneva, Radka; Bauernfeind, Adolf; Mitev, Vanyo; Mitov, Ivan

    2015-10-01

    A total of 36 consecutive clinical and two fecal-screening carbapenem-resistant Klebsiella pneumoniae isolates from two Bulgarian university hospitals (Varna and Pleven) were investigated. Susceptibility testing, conjugation experiments, and plasmid replicon typing were carried out. Beta-lactamases were characterized by isoelectric focusing, PCR, and sequencing. Clonal relatedness was investigated by RAPD and multilocus sequence typing (MLST). Most of the isolates demonstrated multidrug resistance profile. Amikacin and tigecycline retained good activity with susceptibility rates of 95 and 87%, respectively. The resistance rate to colistin was 63%. Six RAPD- and MLST-types were identified: the dominating MLST-type was ST15 (27 isolates), followed by ST76 (six isolates), and ST1350 (two isolates). ST101, ST258, and ST151 were detected once. All except one of the K. pneumoniae produced KPC-2, mostly in combination with CTX-M-15, while for one isolate (ST101) the enzymes OXA-48 and CTX-M-14 were found. All KPC-2-producing transconjugants revealed the presence of IncFII plasmid. The OXA-48- and CTX-M-14-producing isolate showed the presence of L/M replicon type. The dissemination of KPC-2-producing K.pneumoniae in Bulgaria is mainly due to the sustained spread of successful ST15 clone and to a lesser extent of ST76 clone. This is the first report of OXA-48 producing ST101 K. pneumoniae in Bulgaria.

  15. Risk Factor Analysis of Ciprofloxacin-Resistant and Extended Spectrum Beta-Lactamases Pathogen-Induced Acute Bacterial Prostatitis in Korea.

    Science.gov (United States)

    Lee, Young; Lee, Dong Gi; Lee, Sang Hyub; Yoo, Koo Han

    2016-11-01

    The objectives of this study were to investigate risk factors and the incidence of ciprofloxacin resistance and extended-spectrum beta-lactamases (ESBL) in patients with acute bacterial prostatitis (ABP). We reviewed the medical records of 307 patients who were diagnosed with ABP between January 2006 and December 2015. The etiologic pathogens and risk factors for ciprofloxacin-resistant E. coli and ESBL-producing microbes, susceptibility to ciprofloxacin, and the incidence of ESBL in patients with ABP were described. History of prior urologic manipulation was an independent risk factor for ciprofloxacin-resistant (P = 0.005) and ESBL-producing microbes (P = 0.005). Advanced age (over 60 years) was an independent risk factor for ciprofloxacin-resistant microbes (P = 0.022). The ciprofloxacin susceptibility for Escherichia coli in groups without prior manipulation was documented 85.7%. For groups with prior manipulation, the susceptibility was 10.0%. Incidence of ESBL-producing microbes by pathogen was 3.8% for E. coli and 1.0% for Klebsiella pneumonia in the absence of manipulation group, and 20% and 33.3% in the presence of manipulation group, respectively. Initial treatment of ABP must consider patient's age and the possibility of prior manipulation to optimize patient treatment. With the high rate of resistance to fluoroquinolone, cephalosporins with amikacin, or carbapenems, or extended-spectrum penicillin with beta lactamase inhibitor should be considered as the preferred empirical ABP treatment in the patients with history of prior urologic manipulation.

  16. Antimicrobial Susceptibility and Distribution of TEM and CTX-M Genes among ESBL-producing Klebsiella pneumoniae and Pseudomonas aeruginosa Causing Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    Roya Alavi-Naini

    2014-04-01

    Full Text Available Background: Extended spectrum beta lactamases (ESBLs have been observed in nearly all the species of family Enterobacteriaceae. The enzymes are plasmid mediated and are derived from broad-spectrum beta lactamase TEM and CTX- M by a limited number of mutations. This study was undertaken to characterize ESBL producers among Klebsiella pneumoniae and Pseudomonas aeruginosa by PCR, which were initially screened by phenotypic method. Materials and Methods: A cross-sectional study was performed to evaluate 180 strains (30 K. pneumoniae and 150 P. aeruginosa isolated from urine culture of hospitalized patients (Amir Al-Momenin Hospital, Zabol, south-eastern Iran suffered from urinary tract infections during a period of six months. The prevalence of ESBL producing K. pneumoniae and P. aeruginosa was evaluated by disk diffusion test and polymerase chain reaction (PCR by detecting TEM and CTX-M gene. Results: The results of the study revealed that the prevalence of ESBL producing P. aeruginosa and K. pneumoniae by disk diffusion test was 13.3% for P. aeruginosa and 66.6% for K. pneumoniae. Seventy five percent and 65% of K. pneumoniae harboured the gene TEM and CTX-M, respectively. Forty five percent of P. aeruginosa isolates harboured the gene TEM but none of them demonstrated the gene CTX-M using PCR method. Conclusion: ESBL producing P. aeruginosa and K. pneumoniae isolates showed a high prevalence in this study. Therefore it seems that continuous surveillance is essential to monitor the ESBLs producing microorganisms in hospitals and community

  17. Trends in Extended Spectrum Beta-Lactamase (ESBL) Producing Enterobacteriaceae and ESBL Genes in a Dutch Teaching Hospital, Measured in 5 Yearly Point Prevalence Surveys (2010-2014)

    NARCIS (Netherlands)

    Willemsen, Ina; Oome, Stijn; Verhulst, Carlo; Pettersson, Annika; Verduin, Kees; Kluytmans, Jan

    2015-01-01

    This paper describes the trends in prevalence of ESBL producing Enterobacteriaceae (ESBL-E) and ESBL genes, measured in five consecutive yearly Point Prevalence Surveys (PPS). All patients present in the hospital and in a day-care clinic (including patients on dialysis) on the day of the survey, wer

  18. Prevalence and risk factors for extended-spectrum beta-lactamase or AmpC-producing Escherichia coli in organic dairy herds in the Netherlands

    NARCIS (Netherlands)

    Santman-Berends, I M G A; Gonggrijp, M A; Hage, J J; Heuvelink, A E; Velthuis, A; Lam, T J G M; van Schaik, G

    2016-01-01

    Extended-spectrum β-lactamase and AmpC-producing Escherichia coli (ESBL/AmpC) are an emerging problem and are hypothesized to be associated with antimicrobial use (AMU), and more specifically with the use of third- and fourth-generation cephalosporins. Whether ESBL/AmpC also occur in organic dairy h

  19. Clinical profiles of patients colonized or infected with extended-spectrum beta-lactamase producing Enterobacteriaceae isolates: a 20 month retrospective study at a Belgian University Hospital

    Directory of Open Access Journals (Sweden)

    Jamart Jacques

    2011-01-01

    Full Text Available Abstract Background Description of the clinical pictures of patients colonized or infected by ESBL-producing Enterobacteriaceae isolates and admitted to hospital are rather scarce in Europe. However, a better delineation of the clinical patterns associated with the carriage of ESBL-producing isolates may allow healthcare providers to identify more rapidly at risk patients. This matter is of particular concern because of the growing proportion of ESBL-producing Enterobacteriaceae species isolates worldwide. Methods We undertook a descriptive analysis of 114 consecutive patients in whom ESBL-producing Enterobacteriaceae isolates were collected from clinical specimens over a 20-month period. Clinical data were obtained through retrospective analysis of medical record charts. Microbiological cultures were carried out by standard laboratory methods. Results The proportion of ESBL-producing Enterobacteriaceae strains after exclusion of duplicate isolates was 4.5% and the incidence rate was 4.3 cases/1000 patients admitted. Healthcare-associated acquisition was important (n = 104 while community-acquisition was less frequently found (n = 10. Among the former group, two-thirds of the patients were aged over 65 years and 24% of these were living in nursing homes. Sixty-eight (65% of the patients with healthcare-associated ESBL, were considered clinically infected. In this group, the number and severity of co-morbidities was high, particularly including diabetes mellitus and chronic renal insufficiency. Other known risk factors for ESBL colonization or infection such as prior antibiotic exposure, urinary catheter or previous hospitalisation were also often found. The four main diagnostic categories were: urinary tract infections, lower respiratory tract infections, septicaemia and intra-abdominal infections. For hospitalized patients, the median hospital length of stay was 23 days and the average mortality rate during hospitalization was 13% (Confidence

  20. Rapid detection of enterobacteriaceae producing extended spectrum beta-lactamases directly from positive blood cultures by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

    Science.gov (United States)

    Oviaño, M; Fernández, B; Fernández, A; Barba, M J; Mouriño, C; Bou, G

    2014-11-01

    Bacteria that produce extended-spectrum β-lactamases (ESBLs) are an increasing healthcare problem and their rapid detection is a challenge that must be overcome in order to optimize antimicrobial treatment and patient care. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has been used to determine resistance to β-lactams, including carbapenems in Enterobacteriaceae, but the methodology has not been fully validated as it remains time-consuming. We aimed to assess whether MALDI-TOF can be used to detect ESBL-producing Enterobacteriaceae from positive blood culture bottles in clinical practice. In the assay, 141 blood cultures were tested, 13 of them were real bacteraemias and 128 corresponded to blood culture bottles seeded with bacterial clinical isolates. Bacteraemias were analysed by MALDI-TOF after a positive growth result and the 128 remaining blood cultures 24 h after the bacterial seeding. β-lactamase activity was determined through the profile of peaks associated with the antibiotics cefotaxime and ceftazidime and its hydrolyzed forms. Clavulanic acid was added to rule out the presence of non-ESBL mechanisms. Overall data show a 99% (103 out of 104) sensitivity in detecting ESBL in positive blood cultures. Data were obtained in 90 min (maximum 150 min). The proposed methodology has a great impact on the early detection of ESBL-producing Enterobacteriaceae from positive blood cultures, being a rapid and efficient method and allowing early administration of an appropriate antibiotic therapy.

  1. Characterization of multidrug-resistant and metallo-beta lactamase-producing Pseudomonas aeruginosa isolates from a paediatric clinic in China

    Institute of Scientific and Technical Information of China (English)

    DONG Fang; XU Xi-wei; SONG Wen-qi; LU Ping; YU Sang-jie; YANG Yong-hong; SHEN Xu-zhuang

    2008-01-01

    Background In the present study,we characterized multidrug-resistant Pseudomonas aeruginosa (MDRP) clinical isolates from a paediatric facility and investigated the types and features of the metallo-β-lactamases (MBLs) produced by carbapenem-resistant strains.Methods Four hundred and ninety-eight strains of Pseudomonas aeruginosa were isolated from patients at Beijing Children's Hospital between January 2005 and December 2006.The minimal inhibition concentrations (MICs) of the strains for 13 antibiotics were measured.A combination of the E test and PCR amplification/DNA sequencing was used to define the carbapenem-resistant strains.Results We found that 24.1% (120/498) of the isolates were MDRP.The frequencies of resistance to imipenem and meropenem were 34.2% and 35.8%,respectively,and the MIC50 and MIC50 values for the two antibiotics were identical at 4 μg/ml and 32 μg/ml,respectively.The detection rate for carbapenem resistance was 49.2% (59/120).Among the 59 carbapenem-resistant Pseudomonas aeruginosa strains,39 (66.1%) were positive for the MBL genotype;35 (89.7%)strains carded the blaIMP gene and 4 (10.3%) strains carried the blaVIM gene.Neither blaSPM nor blaa~M was amplified from any of the 59 isolates.DNA sequencing revealed that IMP-1 was present in 35 IMP-producing isolates and VIM-2 was detected in four VIM-producing isolates.Conclusions These MDRP isolates exhibited high frequencies of resistance to carbapenems among clinical isolates from a paediatric facility in Beijing,China.The production of MBL appears to be an important mechanism for carbapenem resistance in Pseudomonas aeruginosa.

  2. Carbapenems Versus Piperacillin-Tazobactam for Bloodstream Infections of Nonurinary Source Caused by Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae.

    Science.gov (United States)

    Ofer-Friedman, Hadas; Shefler, Coral; Sharma, Sarit; Tirosh, Amit; Tal-Jasper, Ruthy; Kandipalli, Deepthi; Sharma, Shruti; Bathina, Pradeep; Kaplansky, Tamir; Maskit, Moran; Azouri, Tal; Lazarovitch, Tsilia; Zaidenstein, Ronit; Kaye, Keith S; Marchaim, Dror

    2015-08-01

    A recent, frequently quoted study has suggested that for bloodstream infections (BSIs) due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL) Escherichia coli, treatment with β-lactam/β-lactamase inhibitors (BLBLIs) might be equivalent to treatment with carbapenems. However, the majority of BSIs originate from the urinary tract. A multicenter, multinational efficacy analysis was conducted from 2010 to 2012 to compare outcomes of patients with non-urinary ESBL BSIs who received a carbapenem (69 patients) vs those treated with piperacillin-tazobactam (10 patients). In multivariate analysis, therapy with piperacillin-tazobactam was associated with increased 90-day mortality (adjusted odds ratio, 7.9, P=.03). For ESBL BSIs of a non-urinary origin, carbapenems should be considered a superior treatment to BLBLIs.

  3. Trends in Extended Spectrum Beta-Lactamase (ESBL) Producing Enterobacteriaceae and ESBL Genes in a Dutch Teaching Hospital, Measured in 5 Yearly Point Prevalence Surveys (2010-2014).

    Science.gov (United States)

    Willemsen, Ina; Oome, Stijn; Verhulst, Carlo; Pettersson, Annika; Verduin, Kees; Kluytmans, Jan

    2015-01-01

    This paper describes the trends in prevalence of ESBL producing Enterobacteriaceae (ESBL-E) and ESBL genes, measured in five consecutive yearly Point Prevalence Surveys (PPS). All patients present in the hospital and in a day-care clinic (including patients on dialysis) on the day of the survey, were screened for perianal ESBL-E carriage. Perianal swabs were taken and cultured using an enrichment broth and a selective agar plate. Both phenotypic and genotypic methods were used to detect the production of ESBL, presence of ESBL-genes and clonal relatedness. Out of 2,695 patients, 135 (5.0%) were tested ESBL-E positive. The overall ESBL-E prevalence was stable over the years. Overall 5.2% of all ESBL-E were acquired by nosocomial transmission. A relative decrease of CTX-M-1-1-like ESBL genes (from 44 to 25%, p = 0.026) was observed, possibly related to the strong (>60%) decrease in antibiotic use in livestock in our country during the same period.

  4. Characterization of extended-spectrum beta-lactamase, carbapenemase, and plasmid quinolone determinants in Klebsiella pneumoniae isolates carrying distinct types of 16S rRNA methylase genes, and their association with mobile genetic elements.

    Science.gov (United States)

    Wei, Dan-Dan; Wan, La-Gen; Yu, Yang; Xu, Qun-Fei; Deng, Qiong; Cao, Xian-Wei; Liu, Yang

    2015-04-01

    Eighty-four multidrug-resistant Klebsiella pneumoniae (MDR-KP) isolates from a Chinese hospital from January to October 2012 were evaluated to characterize the coexistence of 16S rRNA methylase, extended-spectrum β-lactamase, carbapenemase, and plasmid-mediated quinolone resistance determinants and their association with mobile genetic elements. Among the 84 MDR-KP isolates studied, 19 isolates exhibited high-level resistance to amikacin mediated by the production of the 16S rRNA methylase. They carried 19 armA genes (22.9%) and three rmtB genes (3.6%). CTX-M genes were found in all of the isolates. Among these armA- or rmtB/CTX-M-producing K. pneumoniae isolates, 31.6% carried the carbapenemase genes (blaKPC-2 [26.3%], blaIMP-4 [10.5%], and blaNDM-1 [5.3%]), which made them resistant to imipenem (minimum inhibitory concentration [MIC] ≥16 mg/L). All positive strains possessed qnr-like genes (16 qnrA1, 10 qnrS1, and 7 qnrB4 genes) and 18 harbored an aac(6')-Ib-cr gene. Mobile elements ISEcp1, IS26, ISCR1, ISAba125, and sul-1 integrons were detected in 19/19 (100%), 16/19 (84.2%), 18/19 (94.7%), 9/19 (47.4%), and 18/19 (94.7%) isolates, respectively. The mobilizing elements occurred in different combinations in the study isolates. Majority of armA and qnr genes were in MDR-KP strains carrying integrons containing the ISCR1. Close to 80% of blaTEM-1 and blaSHV-12 were linked to IS26 while ≥90% of blaCTX-Ms and blaCMYs were linked to ISEcp1. ISAba125 was located upstream of blaNDM-1 and some blaCMY-2 genes. In addition, seven transconjugants were available for further analysis, and armA, qnrS1, acc(6')-Ib-cr, blaCTX-M-15, blaTEM-1, and blaNDM-1 were cotransferred. This study points to the dissemination of 16S rRNA methylase genes and the prevalence of selected elements implicated in evolution of resistance determinants in collection of clinical K. pneumoniae in China.

  5. Phenotypic and Genotypic Detection of Metallo-beta-lactamases among Imipenem-Resistant Gram Negative Isolates

    Directory of Open Access Journals (Sweden)

    Mohammad Mohammadzadeh

    2016-08-01

    Full Text Available Background:   Imipenem-resistant gram negative bacteria, resulting from metallo-beta-lactamase (MBLs-producing strains have been reported to be among the important causes of nosocomial infections and of serious therapeutic problem worldwide. Because of their broad range, potent carbapenemase activity and resistance to inhibitors, these enzymes can confer resistance to almost all beta-lactams. The prevalence of metallo-beta-lactamase among imipenem-resistant Acinetobacter spp., Pseudomonas spp. and Enerobacteriaceae isolates is determined.Methods:   In this descriptive study 864 clinical isolates of Acinetobacter spp., Pseudomonas spp. and Enterobacteriaceae, were initially tested for imipenem susceptibility. The metallo-beta-lactamase production was detected using combined disk diffusion, double disk synergy test, and Hodge test. Then all imipenem resistant isolates were tested by PCR for imp, vim and ndm genes. Results:   Among 864 isolates, 62 (7.17 % were imipenem-resistant. Positive phonetypic test for metallo-beta-lactamase was 40 (64.5%, of which 24 (17.1% and 16 (9.2% isolates were Acinetobacter spp. and Pseudomonas spp., respectively. By PCR method 30 (48.4% of imipenem resistant Acinetobacter, and Pseudomonas isolates were positive for MBL-producing genes. None of the Enterobacteriaceae isolates were positive for metallo-beta-lactamase activity. Conclusion:   The results of this study are indicative of the growing number of nosocomial infections associated with multidrug-resistant gram negative bacteria in this region leading to difficulties in antibiotic therapy. Thereby, using of phenotypic methods can be helpful for management of this problem.

  6. [Susceptibility of ESBL-producing Escherichia coli and Klebsiella pneumoniae to various antibacterial agents].

    Science.gov (United States)

    Nakamura, Tatsuya; Komatsu, Masaru

    2005-02-01

    With the increasing use of broad-spectrum antibacterial agents, the increase in various drug-resistant bacterial strains has become a concern in recent years. Especially, the development of drug-resistance by Enterobacteriaceae which significantly affects therapy and prognosis in sepsis and lower gastrointestinal post-operative infection. The extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae strains isolated in the Surveillance Program of Bacterial Resistance in Kinki region of Japan (SBRK) were supplied between November 2000 and March 2003. The susceptibilities of them to 16 kinds of antimicrobial agents were investigated. The number of them was 48 strains consisting of 36 Escherichia coli strains (75%) and 12 Klebsiella pneumoniae strains (25%). Our focus was on carbapenem and the new quinolone antibacterial agents. Among the 16 major antibacterial agents examined, carbapenem had low MIC50/90 values. Meropenem had a MIC50/90 of 0.03/0.06microg/ml, followed by biapenem (0.12/0.5), imipenem (0.25/0.5) and panipenem (0.25/0.5). Among cephem, ceftazidime had the lowest MIC50 at 4 microg/ml. All four of the cephem agents had a MIC90 of greater than 128microg/ml. Among beta-lactamase inhibitors, tazobactam/piperacillin had the lowest MIC50 at 4 microg/ml, and sulbactam/cefoperazone had a MIC50 of 32 microg/ml. Among the new quinolones, prulifloxacin had the lowest MIC50 at 1 microg/ml, and the other drugs had a MIC50 of 2 microg/ml. The resistance rate of ciprofloxacin was 61.1% in E. coli and 16.6% in K. pneumoniae. Comparison of drug-sensitivity to cephem by ESBL-gene type revealed that cefpirome, cefepime and cefozopran had higher MIC50/90 values against the CTX-M group with a MIC50 of greater than 128microg/ml. Ceftazidime and aztreonam had higher MIC50/90 values against the TEM/SHV group than those against the CTX-M group. In the CTX-M group, the MIC50 was 4 and 16microg/ml, respectively.

  7. Detection of OXA-48-like and NDM carbapenemases producing Klebsiella pneumoniae in Jordan: A pilot study.

    Science.gov (United States)

    Aqel, Amin A; Giakkoupi, Panagiota; Alzoubi, Hamed; Masalha, Ibrahim; Ellington, Matthew J; Vatopoulos, Alkiviadis

    Little is known of carbapenemase producing Klebsiella pneumoniae (CPK) in Jordan. This study aimed to determine the prevalence of CPK in a major hospital in Amman, Jordan in 2012-2013 and to characterize the isolates and detect the types of carbapenemase(s) they produced. For the 296 isolates investigated, species identification and antimicrobial susceptibilities were determined (Vitek II, bioMérieux). Isolates with decreased ertapenem susceptibility were tested for carbapenemase production using the Modified Hodge Test. Isolates with a carbapenemase-positive phenotype were characterized further via multiplex PCRs for extended-spectrum β-lactamase and carbapenemase genes and by Pulsed Field Gel Electrophoresis (PFGE). Seven of 296 K. pneumoniae isolated in 2012-2013 (2.4%) were carbapenemase producers, five produced class D carbapenemases (OXA-48-like) and two produced a NDM metallo-beta-lactamase. All seven isolates also encoded CTX-M enzymes; CTX-M-1-like enzymes were detected in five isolates (two co-producing NDM enzymes and three co-producing OXA-48-like enzymes), CTX-M-9 was found in the two remaining OXA-48-like producers. PFGE revealed five genetically distinct types amongst the seven carbapenemase producing K. pneumoniae, with two pairs of identical isolates associated with patients treated on the same wards. The emergence of OXA-48-like and NDM carbapenemases associated with multi-drug resistant (MDR) isolates in Jordan is concerning. The strict implementation of infection control practices will help to disrupt the spread of MDR carbapenemase producers in Jordanian hospitals.

  8. Design, synthesis, and evaluation of 2 beta-alkenyl penam sulfone acids as inhibitors of beta-lactamases.

    Science.gov (United States)

    Richter, H G; Angehrn, P; Hubschwerlen, C; Kania, M; Page, M G; Specklin, J L; Winkler, F K

    1996-09-13

    A general method for synthesis of 2 beta-alkenyl penam sulfones has been developed. The new compounds inhibited most of the common types of beta-lactamase. The level of activity depended very strongly on the nature of the substituent in the 2 beta-alkenyl group. The inhibited species formed with the beta-lactamase from Citrobacter freundii 1205 was sufficiently stable for X-ray crystallographic studies. These, together with UV absorption spectroscopy and studies of chemical degradation, suggested a novel reaction mechanism for the new inhibitors that might account for their broad spectrum of action. The (Z)-2 beta-acrylonitrile penam sulfone Ro 48-1220 was the most active inhibitor from this class of compound. The inhibitor enhanced the action of, for example, ceftriaxone against a broad selection of organisms producing beta-lactamases. The organisms included strains of Enterobacteriaceae that produce cephalosporinases, which is an exceptional activity for penam sulfones.

  9. PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY OF ESBL AND AMPC β-LACTAMASES PRODUCING ESCHERICHIA COLI AND KLEBSIELLA PNEUMONIAE FROM VARIOUS CLINICAL SAMPLES: AN EMERGING THREAT

    Directory of Open Access Journals (Sweden)

    Rajendra

    2016-04-01

    Full Text Available Resistance to broad spectrum β-lactams mediated by Extended Spectrum β-lactamases (ESBL and AmpC β-lactamases enzymes is a growing threat worldwide. AIM The aim of the study was to detect the prevalence and antimicrobial susceptibility of ESBL and AmpC β-lactamase producing Escherichia coli and Klebsiella pneumoniae isolated from various clinical samples. MATERIALS AND METHODS A total of 288 isolates comprising of 180 Escherichia coli and 108 Klebsiella pneumoniae isolated from various clinical samples were included. ESBL was detected by Phenotypic Confirmatory Disc Diffusion Test (PCDDT and Double Disk Synergy Test (DDST. AmpC detection was done by AmpC disk test. RESULTS Out of 180 Escherichia coli and 108 Klebsiella pneumoniae isolates 91 (50.5% and 63 (58.3% were confirmed to be ESBL producers by PCDDT and 81 (45% and 57 (52.7% by DDST respectively. AmpC was detected in 35 (19.4% of Escherichia coli and 33 (30.5% of Klebsiella pneumoniae isolates. Co-production of ESBL and AmpC was detected in 6 (3.3% Escherichia coli and 11 (10.2% of Klebsiella pneumoniae isolates. Majority of ESBL producers were from blood in both organisms. Multidrug resistance (MDR was seen in 79.1% of ESBL Escherichia coli and 63.5% of ESBL Klebsiella pneumoniae isolates. MDR was seen in 28 (96.5% of AmpC producing Escherichia coli and all AmpC producing Klebsiella pneumoniae isolates. CONCLUSION It is essential to report ESBL and AmpC beta lactamase production along with routine susceptibility, which will aid the clinicians in prescribing antibiotics. Strict adherence to the hospital antibiotic policy and good infection control practices would go a long way in curtailing the menace of drug resistance.

  10. Extended spectrum beta-lactamase detection in gram-negative bacilli of nosocomial origin

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    Dechen C Tsering

    2009-01-01

    Full Text Available Background: Resistance to third generation cephalosporins by acquisition and expression of extended spectrum beta lactamase (ESBL enzymes among gram-negative bacilli is on a rise. The presence of ESBL producing organisms significantly affects the course and outcome of an infection and poses a challenge to infection management worldwide. Materials and Methods: In the period from June 2007 to 2008, we collected 1489 samples from patients suspected of nosocomial infection. The isolates were identified based on colony morphology and biochemical reaction. Gram negative bacilli resistant to third generation cephalosporins were tested for ESBL by double disc synergy test (DDST- a screening test and then phenotypic confirmatory test. Antimicrobial susceptibility testing was done by modified Kirby Bauer disc diffusion method. Results: From the sample of 238 gram-negative bacilli, we isolated Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Citrobacter freundii, Proteus mirabilis, Morganella morganii and Enterobacter cloacae. Following both methods, 34% isolates were ESBL-positive. The ESBL producing isolates were significantly resistant (p < 0.01 to ampicillin, piperacillin, piperacillin/tazobactam, trimethoprim/sulfamethoxazole, tetracycline, ciprofloxacin and gentamicin as compared to non-ESBL producers. Multidrug resistance was significantly (p < 0.01 higher (69.14% in ESBL positive isolates than non-ESBL isolates (21.66%. Conclusion: High prevalence of ESBL in our hospital cannot be ignored. ESBL producers can be detected by DDST and phenotypic confirmatory test with equal efficacy. The sensitivity of screening test improved with the use of more than one antibiotic and addition of one or two antibiotics would not increase cost and labor. We recommend DDST using multiple antibiotics in all microbiology units as a routine screening test.

  11. Detection of genes mediating beta-lactamase production in isolates of enterobacteria recovered from wild pets in Saudi Arabia

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    Sabry A. Hassan

    2015-12-01

    Full Text Available Aim: To determine the genetic basis and types of beta-lactamase encountered among enterobacterial isolates of wild pets from the animal exhibit. Materials and Methods: A total of 17 beta-lactamase-producing enterobacteria recovered from fecal samples of wild pet animals were analyzed for a selected beta-lactamase gene by polymerase chain reaction. Results: Molecular analysis identified one or more β-lactamase-encoding genes in 14 enterobacterial isolates as a single or gene combination. The most frequent extended-spectrum β-lactamases types were transmission electron microscopy and CTX-M, and the most common AmpC enzymes were CMY-2 and DHA types. Conclusions: The study is the first in Saudi Arabia, have established the presence of β-lactamase-encoding genes in the fecal isolates of wild pets.

  12. Extended-spectrum beta-lactamase orthopedic wound infections in Nigeria

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    Olusolabomi J Idowu

    2011-01-01

    Full Text Available Background: Extended-spectrum beta-lactamase (ESBL-producing Gram-negative bacteria are emerging and impacting significantly on the management of patients and hospital costs. Besides, they are not being routinely sought after in diagnostic laboratories thus contributing to treatment failure. Materials and Methods: Bacterial isolates from wounds of 45 patients were identified using commercial identification kits and antibiotic susceptibility was evaluated by the Bauer-Kirby method. Screening and phenotypic confirmation of ESBL production were done as prescribed by the Clinical and Laboratory Standards Institute. The conjugation experiment was performed by the mating assay in broth between the ESBL producers and E. coli ATCC 25922 as the recipient. Results: Out of 102 Gram-negative bacteria isolated, 36 were positive for ESBL mainly of the Enterobacteriaceae family (33 and the rest were oxidase-positive bacilli (3. The predominant bacteria were Klebsiella spp. and E. coli. Others were Serratia rubidae, Citrobacter freundii, Morganella morgannii, Proteus spp., Providencia stuartii, and Enterobacter spp. There was a significant association between treatment with third-generation cephalosporins (3GCs and isolation of ESBLs ( p=0.0020 . The ESBL producers were multiply resistant and moderately sensitive to colistin. The conjugation experiment showed that the ESBL gene was transferred horizontally and tetracycline, cotrimoxazole, nitrofurantoin, gentamicin, and aztreonam resistance genes were co-transferred. No mortality was recorded but the mean length of stay in the hospital was 82 days. Conclusion: The development and spread of ESBL among Gram-negative bacteria and possible horizontal transfer calls for concern, especially in view of treatment failure, high treatment cost, and consequent discomfort to patients.

  13. CTX-M-type extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolated from cases of bovine mastitis in Japan.

    Science.gov (United States)

    Saishu, Nobukazu; Ozaki, Hiroichi; Murase, Toshiyuki

    2014-08-01

    Three Klebsiella pneumoniae isolates producing extended-spectrum beta-lactamase (ESBL) were obtained from three dairy cows with clinical mastitis in two farms in western Japan. Two of the 3 isolates from cows in different farms were able to transfer plasmids carrying the blaCTX-M-2 gene to Escherichia coli recipient. Pulsed-field gel electrophoresis (PFGE) patterns of the 2 isolates were different from each other, although restricted-fragment patterns of the two conjugative plasmids were similar to each other. Additionally, PCR-based replicon typing revealed that both the plasmids belonged to type Inc.T. These results suggest that ESBL-encoding genes can be distributed in bacteria on dairy farms through the plasmids.

  14. 快速筛查革兰阴性杆菌β内酰胺酶%Quick screening test of beta-lactamase in gram-negative bacilli

    Institute of Scientific and Technical Information of China (English)

    汪雅萍; 杨俊; 应春妹; 杜坤; 张灏旻; 郑冰

    2012-01-01

    目的 应用Cica-Beta-Test试剂盒快速筛查革兰阴性杆菌β内酰胺酶:超广谱β内酰胺酶(ESBLs)、金属β内酰胺酶(MBLs)和染色体介导头孢菌素酶(AmpC酶),为临床抗感染治疗提供耐药依据.方法 收集2010年1月至2011年3月上海交通大学医学院附属仁济医院临床分离革兰阴性杆菌共110株,其中头孢噻肟和(或)头孢他啶不敏感大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌各20株,多重耐药鲍曼不动杆菌20株和阴沟肠杆菌30株.其中大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌用美国CLSI推荐方法确证产ESBLs;对鲍曼不动杆菌用聚合酶链反应(PCR)法检测其MBLs和AmpC酶耐药基因;对阴沟肠杆菌用表型筛选法(三维试验法)检测其AmpC酶;对所有菌株应用Cica-Beta-Test试剂盒快速筛查ESBLs、MBLs和AmpC酶.根据检测结果对试剂盒进行评估.结果 应用Cica-Beta-Test试剂盒检测110株临床分离菌未发现假阳性,确诊试验总符合率为92.0%(92/100),其中与PCR法比较检测MBLs和AmpC酶结果符合率为100%;与CLSI推荐ESBLs双纸片确诊试验比较,符合率为86.7%(52/60).30株阴沟肠杆菌用AmpC酶表型筛选法比较符合率为86.7%(26/30).结论 Ciea-Beta-Test试剂盒可对各种革兰阴性杆菌产生的β内酰胺酶进行筛查及初步分型,简便、快速,灵敏度高,准确率高,尤其能对CLSI未推荐方法的耐药革兰阴性杆菌进行β内酰胺酶快速筛查意义更大.%Objective To screen and differentiate the various beta-lactamases produced by gram-negative bacilli using a novel kit (Cica-Beta Test) and to provide reference for clinical antimicrobial therapy. Methods A total of 110 clinical strains of gram-negative bacilli were collected from Renji Hospital from January 2010 to March 2011, of which there were 20 strains of Escherichia coli, Klebsiella pneumoniae and Proteus mirabiiis each. All of these strains were not sensitive to cefotaxime and

  15. Evaluation of Four Commercially Available Extended-Spectrum Beta-Lactamase Phenotypic Confirmation Tests

    OpenAIRE

    2005-01-01

    Extended-spectrum beta-lactamase (ESBL) production in members of the Enterobacteriaceae can confer resistance to extended-spectrum cephalosporins, aztreonam, and penicillin. As such, the accurate detection of ESBL producers is essential for the appropriate selection of antibiotic therapy. Twenty previously characterized isolates and 49 clinical isolates suspected of ESBL production were tested by four ESBL phenotypic confirmatory methods for accuracy and ease of use. The four ESBL phenotypic ...

  16. Contribution of OmpK36 to carbapenem susceptibility in KPC-producing Klebsiella pneumoniae.

    Science.gov (United States)

    Landman, David; Bratu, Simona; Quale, John

    2009-10-01

    Isolates of Klebsiella pneumoniae harbouring the carbapenemase KPC may have carbapenem MICs that remain in the susceptible range, and may therefore go unrecognized. To understand the mechanisms contributing to the variability in carbapenem MICs, 20 clinical isolates, all belonging to either of two clonal groups of KPC-possessing K. pneumoniae endemic to New York City, were examined. Expression of genes encoding KPC, the porins OmpK35 and OmpK36, and the efflux pump AcrAB was examined by real-time RT-PCR. Outer-membrane profiles of selected KPC-producing isolates were examined by SDS-PAGE, and proteins were identified by matrix-assisted laser desorption/ionization mass spectrometry. The identification of SHV and TEM beta-lactamases and the genomic sequences of ompK35 and ompK36 were determined by PCR and DNA sequencing, respectively. For one clonal group, carbapenem MICs increased with decreasing expression of ompK36. A second clonal group also had carbapenem MICs that correlated with ompK36 expression. However, all of the isolates in this latter group continued to produce OmpK36, suggesting that porin configuration may affect entry of carbapenems. For isolates that had the greatest expression of ompK36, carbapenem MICs tended to be lower when determined by the broth microdilution technique, and scattered colonies were seen around the Etest zones of inhibition. All of the KPC-producing isolates were highly resistant to ertapenem, regardless of ompK36 expression. In conclusion, isolates of KPC-possessing K. pneumoniae that express ompK36 tend to have lower MICs to carbapenems and therefore may be more difficult to detect by clinical laboratories. Regardless of ompK36 expression, all of the KPC producers were consistently resistant to ertapenem.

  17. Molecular characterization of extended-spectrum beta-lactamases and its correlation with clinical laboratory standards institute interpretive criteria for disk diffusion susceptibility testing in enterobacteriaceae isolates in Thaialnd.

    Science.gov (United States)

    Tangkoskul, Teerawit; Tiengrim, Surapee; Onsomang, Supiluck; Pati, Naratchaphan; Aswapokee, Nalinee; Thamlikitkul, Visanu; Chayakulkeeree, Methee

    2012-11-01

    We performed extended-spectrum beta-lactamase (ESBL) phenotypic testing and molecular characterization of three ESBL genes (TEM, SHV and CTX-M) and susceptibility testing by Clinical Laboratory Standards Institute (CLSI) disk diffusion method against three cephalosporins (ceftriaxone, ceftazidime, cefepime) and a cephamycin (cefoxitin) among 128 Thai Escherichia coli and 84 Thai Klebsiella pneumoniae clinical isolates. ESBL production was discovered in 62% of E. coli and 43% of K. pneumoniae isolates. All isolates susceptible to ceftriaxone were ESBL-negative. Nearly all isolates non-susceptible to ceftriaxone, ceftazidime and cefepime produced ESBL; the presence of CTX-M genes in the isolates correlated with a ceftriaxone non-susceptible phenotype. Thirty-nine of 83 isolates (47%) of ceftazidime-susceptible E. coli and 50 of 99 isolates (50.5%) of cefepime-susceptible E. coli were ESBL-producing. SHV-type beta-lactamase genes were more prevalent among K. pneumoniae than E. coli isolates. CTX-M was the major ESBL gene harbored by ESBL-producers in both E. coli and K. pneumoniae isolates. Non-CTX-M ESBL-producers were found only among K. pneumoniae isolates. This study reveals an increase in ESBL-producing Enterobacteriaceae among Thai isolates and demonstrates gaps in the current CLSI disk diffusion susceptibility guidelines; it indicates the results of ceftazidime and cefepime disk diffusion susceptibility testing using CLSI criteria should be interpreted with caution.

  18. Elaboration and evaluation of a new screening medium for detection and presumptive identification of extended-spectrum beta-lactamase-producing organisms (ESBL Elaboração e avaliação de um novo meio de triagem para a detecção e identificação presuntiva de enterobactérias produtoras de beta-lactamase de espectro estendido (ESBL

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Pessôa de Menezes e Silva

    2000-10-01

    Full Text Available The new ß-lactamases have arisen largely as a consequence of heavy use of new expanded spectrum ß-lactam antibiotics. Health professionals need to be aware of the resistance problems caused by the new enzymes, and know the correct procedures to detect, prevent and control such problems. In this study, a new screening medium called Ceftazidime-Inositol-Vancomycin-Amphotericin B Agar (CIVA was elaborated and the microbiological performance was evaluated for the detection and presumptive identification of ESBL-producing members of Enterobacteriaceae. It was performed in 126 stool samples from hospitalized patients at Santa Monica Hospital (Vila Velha, ES, Brazil, who had been heavily exposed to broad-spectrum antibiotic combinations. The bacteria were detected by the medium based on their colony colours (due to inositol fermentation. Additional tests were required for correct identification of these strains. No false positive rates were detected.As novas beta-lactamases têm aparecido, na maioria das vezes, como consequência do amplo uso de antibióticos beta-lactâmicos de largo espectro. Os profissionais de saúde precisam estar atentos acerca do problema da resistência bacteriana causado por estas novas enzimas e conhecer os corretos procedimentos para detectar, prevenir e controlar tais situações. Neste estudo, um novo meio de triagem foi desenvolvido no setor de Microbiologia do Marcos Daniel Laboratório - Vitória, ES (denominado CIVA - Ceftazidima-Inositol-Vancomicina-Anfotericina B e a sua performance microbiológica foi avaliada quanto à detecção e identificação presuntiva de enterobactérias produtoras de ESBL. Foram realizadas 126 culturas de amostras fecais de pacientes hospitalizados no Hospital Santa Monica (Vila Velha, ES, Brasil, previamente expostos a combinações de antibióticos de largo espectro. As bactérias foram detectadas pelo meio baseado nas cores das colônias desenvolvidas (devido à fermentação do

  19. Genetic structures at the origin of acquisition of the beta-lactamase bla KPC gene.

    Science.gov (United States)

    Naas, Thierry; Cuzon, Gaelle; Villegas, Maria-Virginia; Lartigue, Marie-Frédérique; Quinn, John P; Nordmann, Patrice

    2008-04-01

    Genetic structures surrounding the carbapenem-hydrolyzing Ambler class A bla KPC gene were characterized in several KPC-positive Klebsiella pneumoniae and Pseudomonas aeruginosa strains isolated from the United States, Colombia, and Greece. The bla KPC genes were associated in all cases with transposon-related structures. In the K. pneumoniae YC isolate from the United States, the beta-lactamase bla KPC-2 gene was located on a novel Tn3-based transposon, Tn4401. Tn4401 was 10 kb in size, was delimited by two 39-bp imperfect inverted repeat sequences, and harbored, in addition to the beta-lactamase bla KPC-2 gene, a transposase gene, a resolvase gene, and two novel insertion sequences, ISKpn6 and ISKpn7. Tn4401 has been identified in all isolates. However, two isoforms of this transposon were found: Tn4401a was found in K. pneumoniae YC and K. pneumoniae GR from the United States and Greece, respectively, and differed by a 100-bp deletion, located just upstream of the bla KPC-2 gene, compared to the sequence of Tn4401b, which was found in the Colombian isolates. In all isolates tested, Tn4401 was flanked by a 5-bp target site duplication, the signature of a recent transposition event, and was inserted in different open reading frames located on plasmids that varied in size and nature. Tn4401 is likely at the origin of carbapenem-hydrolyzing beta-lactamase KPC mobilization to plasmids and its further insertion into various-sized plasmids identified in nonclonally related K. pneumoniae and P. aeruginosa isolates.

  20. Detection of Beta-Lactamase and Extended-Spectrum Beta-Lactamase of Pathogens Isolated from Pig and Chicken and Their Antibiotic Susceptibility Test

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The antibacterial activity of beta-lactam antibiotics or their combinations with inhibitor sulbactum against non-lactamaseproducing strains, lactamase-producing and ESBLs-producing isolates was evaluated with twofold dilution method after pathogens isolated from pigs and chickens were detected, respectively, for beta-lactamase and extended-spectrum betalactamases (ESBLs). The results revealed that most of 43 clinically isolated strains could produce beta-lactamase and 3strains of shigella isolated from chicken samples produced ESBLs. All of 30 lactamase-producing strains isolated and only one of 16 non-lactamase-producing strains were resistant to amoxicillin and ampicillin. MICs of ampicillin against lactamaseproducing isolates decreased 10-40 and 10-20 times respectively, when it was conbined with sulbactam at ration of 1:2 and 1:4. All clinical isolates were susceptible to third-generation cephalosporins. The MICs of third-generation cephalosporins against lactamase-producing isolates did not change when they were conbined with sulbactam. MICs of ceftiofur and ceftriaxone against ESBLs-producing isolates decreased 2-4 times when they were conbined with sulbactam.

  1. 改良亚胺培南-EDTA纸片增效试验检测铜绿假单胞菌产金属酶表型%The phenotypic detection of metallo-beta-lactamase-producing Pseudomonas aeruginosa by modified imipenem-EDTA disk potentiation test

    Institute of Scientific and Technical Information of China (English)

    严育忠; 范惠清; 郑文龙; 杨焕章; 陆燕春; 石毅

    2014-01-01

    目的:评估改良亚胺培南-乙二胺四乙酸(EDTA)纸片增效试验在检测铜绿假单胞菌(PA)产金属酶表型中的应用价值。方法收集95株耐碳青霉烯类药物PA,采用琼脂稀释法测定所有菌株对亚胺培南和美罗培南的最低抑菌浓度(MIC)值,聚合酶链反应(PCR)和DNA测序鉴定金属酶基因型,亚胺培南-EDTA纸片增效试验常规法和改良法检测金属酶表型。结果95株耐碳青霉烯类药物PA对亚胺培南和美罗培南的耐药率分别为100.0%和71.6%;常规法敏感性、特异性、阳性预测值和阴性预测值分别是100.0%、96.6%、72.7%和100.0%,而改良法均为100.0%。结论改良亚胺培南-EDTA纸片增效试验可能是一种检测PA产金属酶表型的有效方法。%Objective To evaluate the modified imipenem-ethylene diamine tetraacetic acid (EDTA ) disk potentiation test for the phenotypic detection of metallo-beta-lactamase-producing Pseudomonas aeruginosa (PA ). Methods A total of 95 carbapenem-resistant PA were collected.The minimum inhibition concentrations(MIC)of imipenem and meropenem were determined by agar dilution method.Polymerase chain reaction (PCR ) and DNA sequencing were used for the identification of metallo-beta-lactamase genotypes.The phenotypic detection of metallo-beta-lactamase was done by conventional and modified imipenem-EDTA disk potentiation test.Results The resistance rates of imipenem and meropenem were 1 00.0%and 71 .6%among these 95 carbapenem-resistant PA.The sensitivity, specificity,positive predictive value and negative predictive value of conventional test were 1 00.0%,96.6%,72.7%and 1 00.0%,respectively.Those of modified test were all 1 00.0%.Conclusions The modified imipenem-EDTA disk potentiation test could be an effective method for the phenotypic detection of metallo-beta-lactamase-producing PA.

  2. National survey of colistin resistance among carbapenemase-producing Enterobacteriaceae and outbreak caused by colistin-resistant OXA-48-producing Klebsiella pneumoniae, France, 2014.

    Science.gov (United States)

    Jayol, Aurélie; Poirel, Laurent; Dortet, Laurent; Nordmann, Patrice

    2016-09-15

    From January 2014 to December 2014, 972 consecutive non-replicate carbapenemase-producing Enterobacteriaceae isolates from colonised or infected patients were collected at the Associated French National Reference Centre as part of the French national survey on antimicrobial resistance. It included 577 Klebsiella spp. (59%), 236 Escherichia coli (24%), 108 Enterobacter spp. (11%), 50 Citrobacter spp. (5%), and a single Salmonella spp. isolate (0.1%). Of 561 K. pneumoniae isolates, 35 were found to be resistant to colistin (6.2%). PFGE analysis revealed a clonal outbreak involving 15 K. pneumoniae isolates belonging to sequence type ST11, recovered in a single hospital in the Picardie region in northern France. Those clonally related isolates showed variable levels of resistance to colistin, ranging from 4 to 64 mg/L. They harboured the blaOXA-48 carbapenemase gene and the blaCTX-M-15 extended-spectrum beta-lactamase gene. Among the 91 Enterobacter cloacae isolates, seven were resistant to colistin and produced different types of carbapenemases. Surprisingly, none of the E. coli and Citrobacter spp. isolates showed resistance to colistin. This national survey including carbapenemase-producing isolates recovered in 2014 reported a high rate of colistin resistance in K. pneumoniae and E. cloacae (6.2% and 7.7%, respectively) in France.

  3. National survey of colistin resistance among carbapenemase-producing Enterobacteriaceae and outbreak caused by colistin-resistant OXA-48-producing Klebsiella pneumoniae, France, 2014

    Science.gov (United States)

    Jayol, Aurélie; Poirel, Laurent; Dortet, Laurent; Nordmann, Patrice

    2016-01-01

    From January 2014 to December 2014, 972 consecutive non-replicate carbapenemase-producing Enterobacteriaceae isolates from colonised or infected patients were collected at the Associated French National Reference Centre as part of the French national survey on antimicrobial resistance. It included 577 Klebsiella spp. (59%), 236 Escherichia coli (24%), 108 Enterobacter spp. (11%), 50 Citrobacter spp. (5%), and a single Salmonella spp. isolate (0.1%). Of 561 K. pneumoniae isolates, 35 were found to be resistant to colistin (6.2%). PFGE analysis revealed a clonal outbreak involving 15 K. pneumoniae isolates belonging to sequence type ST11, recovered in a single hospital in the Picardie region in northern France. Those clonally related isolates showed variable levels of resistance to colistin, ranging from 4 to 64 mg/L. They harboured the blaOXA-48 carbapenemase gene and the blaCTX-M-15 extended-spectrum beta-lactamase gene. Among the 91 Enterobacter cloacae isolates, seven were resistant to colistin and produced different types of carbapenemases. Surprisingly, none of the E. coli and Citrobacter spp. isolates showed resistance to colistin. This national survey including carbapenemase-producing isolates recovered in 2014 reported a high rate of colistin resistance in K. pneumoniae and E. cloacae (6.2% and 7.7%, respectively) in France. PMID:27685838

  4. Laboratory tests in the detection of extended spectrum beta-lactamase production: National Committee for Clinical Laboratory Standards (NCCLS screening test, the E-test, the double disk confirmatory test, and cefoxitin susceptibility testing

    Directory of Open Access Journals (Sweden)

    Pedro A. d'Azevedo

    2004-10-01

    Full Text Available Extended spectrum beta-lactamase (ESBL production by Klebsiella sp. and E. coli is an emerging problem. In this study, 107 clinical isolates (53 E. coli, 47 K. pneumoniae and 7 K. oxytoca screened as ESBL producers by the NCCLS disk diffusion procedure were submitted to a double disk confirmatory test (DDT and to the E-test double strip for confirmation of ESBL production by demonstration of clavulanic acid inhibition effect (CAIE. Only 72/107 (67% of the isolates were confirmed as ESBL producers by DDT, with diverse results among species. By the E-test, 58/107 (54% isolates were confirmed as ESBL producers, and 18/107 (17% were not determinable. Susceptibility to cefoxitin was found in 57/68 (83% of strains that did not show CAIE. ESBL detection remains a controversial issue and clinical laboratories are in need of a simple and effective way to recognize strains with this kind of resistance.

  5. OXA-18, a class D clavulanic acid-inhibited extended-spectrum beta-lactamase from Pseudomonas aeruginosa.

    Science.gov (United States)

    Philippon, L N; Naas, T; Bouthors, A T; Barakett, V; Nordmann, P

    1997-01-01

    Clinical isolate Pseudomonas aeruginosa Mus showed resistance both to extended-spectrum cephalosporins and to aztreonam. We detected a typical double-disk synergy image when ceftazidime or aztreonam was placed next to a clavulanic acid disk on an agar plate. This resistance phenotype suggested the presence of an extended-spectrum beta-lactamase. Isoelectric focusing revealed that this strain produced three beta-lactamases, of pI 5.5, 7.4, and 8.2. A 2.6-kb Sau3A fragment encoding the extended-spectrum beta-lactamase of pI 5.5 was cloned from P. aeruginosa Mus genomic DNA. This enzyme, named OXA-18, had a relative molecular mass of 30.6 kDa. OXA-18 has a broad substrate profile, hydrolyzing amoxicillin, ticarcillin, cephalothin, ceftazidime, cefotaxime, and aztreonam, but not imipenem or cephamycins. Its activity was totally inhibited by clavulanic acid at 2 microg/ml. Hydrolysis constants of OXA-18 (Vmax, Km) confirmed the MIC results. Cloxacillin and oxacillin hydrolysis was noticeable with the partially purified OXA-18. The blaOXA-18 gene encodes a 275-amino-acid protein which has weak identity with all class D beta-lactamases except OXA-9 and OXA-12 (45 and 42% amino acid identity, respectively). OXA-18 is likely to be chromosomally encoded since no plasmid was found in the strain and because attempts to transfer the resistance marker failed. OXA-18 is peculiar since it is a class D beta-lactamase which confers high resistance to extended-spectrum cephalosporins and seems to have unique hydrolytic properties among non-class A enzymes. PMID:9333046

  6. Pseudomonas aeruginosa chromosomal beta-lactamase in patients with cystic fibrosis and chronic lung infection. Mechanism of antibiotic resistance and target of the humoral immune response

    DEFF Research Database (Denmark)

    Ciofu, Oana

    2003-01-01

    of this therapeutic strategy and our results showed the development of resistance of P. aeruginosa to several antibiotics during 25 years of intensive antibiotic treatment. Our studies have been concentrating on the development of resistance to beta-lactam antibiotics. We have shown an association between...... the development of resistance to beta-lactam antibiotics and the occurrence of high beta-lactamase producing strains and between the MIC of the beta-lactams and the levels of beta-lactamase expression. Partially derepressed mutants, characterized by high basal levels of beta-lactamase with the possibility...... of induction to even higher levels during treatment with beta-lactam antibiotics, were the most frequent phenotype found among resistant Danish P. aeruginosa CF isolates. We have also shown that the high alginate producing P. aeruginosa isolates, that characterize the chronic lung infection in CF patients...

  7. Frequency of Klebsiella pneumoniae carbapenemase (KPC) and non-KPC-producing Klebsiella contamination of Healthcare workers and the environment

    Science.gov (United States)

    Rock, Clare; Thom, Kerri A.; Masnick, Max; Johnson, J. Kristie; Harris, Anthony D.; Morgan, Daniel J

    2014-01-01

    We examined contamination of healthcare worker (HCW) gown and gloves after caring for patients with Klebsiella Producing Carbapenemase-producing and non-KPC-producing Klebsiella as a proxy for horizontal transmission. Contamination rate with Klebsiella is similar to MRSA and VRE, with 14% (31/220) of HCW-patient interactions resulting in contamination of gloves and gowns. PMID:24602950

  8. Detection and analysis of the penicillin-binding protein 4 in the AmpC beta-lactamase producing Escherichia coli isolates%产AmpC酶的大肠埃希菌中PBP4的检测及分析

    Institute of Scientific and Technical Information of China (English)

    王欣慧; 蒋燕群

    2012-01-01

    Objective To detect the mRNA expression level of the nonessential penicillin-binding protein 4 (PBP4)dacB gene in AmpC beta-lactaraase producing Escherichia coli isolates, and investigate the effect of PBP4 in the resistant mechanism of AmpC beta-lactamase producing gram-negative isolates. Methods- A total of 34 AmpC beta-lactamase producing Escherichia coli isolates were collected in Shanghai Sixth People's Hospital from 2003 to 2010. The polymerase chain reaction (PCR)was used for the amplification of dacB gene and ampC gene, and the real-time quantitation PCR was used for the detection of the mRNA expression level of dacB. The isolates were classified into 2 groups: the high expression level group and the low expression level group. Real-time quantitation PCR was used for the detection of the mRNA expression level of ampC. The broth microdilution method was used for the detection of sensitivity. Results Among the 34 Escherichia coli,26 (76.47%)of 34 isolates had mRNA overexpression level of dacB,and the mRNA of ampC in the high expression level group was higher than that in the low expression level group (P < 0.05). Conclusions The overexpression of PBP4 may be helpful to introduce high-level resistance by triggering the overexpression of AmpC beta-lactamase among clinical isolates of Escherichia coli.%目的 检测产AmpC β-内酰胺酶(简称AmpC酶)的大肠埃希菌中编码非必需青霉素结合蛋白4( PBP4)的基因dacB mRNA表达水平,探讨PBP4在产AmpC酶的革兰阴性菌耐药机制中的作用.方法 收集上海市第六人民医院2003至2010年间部分产AmpC酶的大肠埃希菌34株,聚合酶链反应(PCR)扩增dacB基因和ampC基因,实时定量PCR检测dacB mRNA表达水平,并分为dacB mRNA表达上调组与dacB mRNA表达下调组,实时定量PCR方法检测ampC mRNA表达水平.微量肉汤稀释法药敏试验检测抗菌药物的敏感性.结果 34株大肠埃希菌中,26株(76.47%) dacB mRNA表达水平上调,dacB m

  9. A putative multi-replicon plasmid co-harboring beta-lactamase genes blaKPC-2, blaCTX-M-14 and blaTEM-1 and trimethoprim resistance gene dfrA25 from a Klebsiella pneumoniae sequence type (ST) 11 strain in China

    Science.gov (United States)

    Tang, Yu; Shen, Pinghua; Liang, Wei; Jin, Jialin; Jiang, Xiaofei

    2017-01-01

    The global emergence of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae poses a major public health threat requiring immediate and aggressive action. Some older generation antibiotics, such as trimethoprim, serve as alternatives for treatment of infections. Here, we determined the complete nucleotide sequence of plasmid pHS091147, which co-harbored the carbapenemase (blaKPC-2) and trimethoprim resistance genes (dfrA25) from a Klebsiella pneumoniae sequence type (ST) 11 clone recovered in Shanghai, China. pHS091147 had three replication genes, several plasmid-stability genes and an intact type IV secretion system gene cluster. Besides blaKPC-2 and dfrA25, pHS091147 carried several other resistance genes, including β-lactamase genes blaTEM-1 and blaCTX-M-14, sulphonamide resistance gene sul1, a quinolone resistance gene remnant (ΔqnrB2), and virulence associated gene iroN. Notably, the multidrug-resistance region was a chimeric structure composed of three subregions, which shared strong sequence homology with several plasmids previously assigned in Genbank. To our knowledge, this is the first report of the co-localization of blaKPC-2 and dfrA25 on a novel putative multi-replicon plasmid in a Klebsiella pneumoniae ST11 clone. PMID:28152085

  10. First report of TEM-104-, SHV-99-, SHV-108-, and SHV-110-producing Klebsiella pneumoniae from Iran

    Directory of Open Access Journals (Sweden)

    Shahram Shahraki-Zahedani

    Full Text Available Abstract: INTRODUCTION: Extended-spectrum beta-lactamases (ESBLs are bacterial enzymes capable of hydrolyzing beta-lactams. The aim of this study was to describe the prevalence of TEM- and SHV-type ESBL-producing Klebsiella pneumoniae strains in Zahedan, Southeast Iran. METHODS: A total of 170 non-repetitive K. pneumoniae strains were collected from patients referred to three teaching hospitals of Zahedan. Antibiotic susceptibility testing was determined for 17 antibiotics using the Kirby-Bauer disc diffusion method. The frequency of ESBL-producing strains was calculated, and minimum inhibitory concentrations of ESBL-producing strains were determined for cefotaxime, ceftazidime, ceftriaxone, and cefpodoxime. The presence of bla TEM and bla SHV genes was tested in all ESBL-producing strains using polymerase chain reaction and DNA sequencing. RESULTS: Among the 170 K. pneumoniae clinical isolates, 55 (32.4% were ESBL producers; 92.7% (n=51 and 72.7% (n=40 of the isolates carried the bla SHV and bla TEM genes, respectively, and 67.3% (n=37 carried both genes. The sequencing results showed that all bla TEM types were bla TEM-1, except for two isolates that were bla TEM-104. The bla SHV types were bla SHV-1, bla SHV-11, bla SHV-12, bla SHV-99, bla SHV-108, and bla SHV-110. CONCLUSIONS: The percentage of bla TEM and bla SHV among ESBL-producing K. pneumoniae isolates from Zahedan is relatively high, indicating the need for further surveillance and consideration in antibiotic use. To the best of our knowledge, this is the first report of TEM-104-, SHV-99-, SHV-108-, and SHV-110-type ESBLs among clinical isolates of K. pneumoniae from Iran, and TEM-1, SHV-1, SHV-11, and SHV-12 appear to be the dominant ESBLs in this region.

  11. Novel Insights Into The Mode of Inhibition of Class A SHV-1 Beta-Lactamases Revealed by Boronic Acid Transition State Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    W Ke; J Sampson; C Ori; F Prati; S Drawz; C Bethel; R Bonomo; F van den Akker

    2011-12-31

    Boronic acid transition state inhibitors (BATSIs) are potent class A and C {beta}-lactamase inactivators and are of particular interest due to their reversible nature mimicking the transition state. Here, we present structural and kinetic data describing the inhibition of the SHV-1 {beta}-lactamase, a clinically important enzyme found in Klebsiella pneumoniae, by BATSI compounds possessing the R1 side chains of ceftazidime and cefoperazone and designed variants of the latter, compounds 1 and 2. The ceftazidime and cefoperazone BATSI compounds inhibit the SHV-1 {beta}-lactamase with micromolar affinity that is considerably weaker than their inhibition of other {beta}-lactamases. The solved crystal structures of these two BATSIs in complex with SHV-1 reveal a possible reason for SHV-1's relative resistance to inhibition, as the BATSIs adopt a deacylation transition state conformation compared to the usual acylation transition state conformation when complexed to other {beta}-lactamases. Active-site comparison suggests that these conformational differences might be attributed to a subtle shift of residue A237 in SHV-1. The ceftazidime BATSI structure revealed that the carboxyl-dimethyl moiety is positioned in SHV-1's carboxyl binding pocket. In contrast, the cefoperazone BATSI has its R1 group pointing away from the active site such that its phenol moiety moves residue Y105 from the active site via end-on stacking interactions. To work toward improving the affinity of the cefoperazone BATSI, we synthesized two variants in which either one or two extra carbons were added to the phenol linker. Both variants yielded improved affinity against SHV-1, possibly as a consequence of releasing the strain of its interaction with the unusual Y105 conformation.

  12. Utility of the ceftazidime-imipenem antagonism test (CIAT to detect and confirm the presence of inducible AmpC beta-lactamases among enterobacteriaceae

    Directory of Open Access Journals (Sweden)

    Vlademir Vicente Cantarelli

    2007-04-01

    Full Text Available Detection of AmpC beta-lactamase production by enterobacteria has been problematic. Contrary to ESBLs, no specific guidelines are available for detection and confirmation of AmpC production by clinical relevant microorganisms. Moreover, some bacterial species may produce inducible AmpC beta-lactamases that can be easily overlooked by routine susceptibility tests. We reported here a new test based on the strong inducible effect of imipenem on AmpC genes and the consequent antagonism with ceftazidime. This test is very simple and proved to be helpful in detecting AmpC-inducible enzymes among several species of clinical isolates.

  13. Escherichia coli with extended-spectrum beta-lactamases or transferable AmpC beta-lactamases and Salmonella on meat imported into Sweden.

    Science.gov (United States)

    Egervärn, Maria; Börjesson, Stefan; Byfors, Sara; Finn, Maria; Kaipe, Caroline; Englund, Stina; Lindblad, Mats

    2014-02-01

    The presence of Enterobacteriaceae producing extended spectrum beta-lactamases (ESBL) or transferable AmpC beta-lactamases (pAmpC) is increasingly being reported in humans and animals world-wide. Their occurrence in food-producing animals suggests that meat is a possible link between the two populations. This study investigated the occurrence and characteristics of Salmonella and ESBL- or pAmpC-producing E. coli in 430 samples of beef, pork and broiler meat imported into Sweden, in order to provide data required for assessing the potential public health risk of these bacteria in food. Depending on region of origin, ESBL/pAmpC-producing E. coli were found in 0-8% of beef samples, 2-13% of pork samples and 15-95% of broiler meat samples. The highest prevalence was in South American broiler meat (95%), followed by broiler meat from Europe (excluding Denmark) (61%) and from Denmark (15%). Isolates from meat outside Scandinavia were generally defined as multiresistant. A majority of the ESBL/pAmpC genes were transferable by conjugation. Bla(CTX-M-2) and bla(CTX-M-8) were the dominant genes in E. coli from South American broiler meat, whereas bla(CMY-2) and bla(CTX-M-1) dominated in European meat. The majority of bla(CMY-2) and bla(CTX-M-1) were situated on plasmids of replicon type incK and incI1, respectively. The same combinations of ESBL/pAmpC genes and plasmids have been described previously in clinical human isolates. Salmonella was found in five samples tested, from European pork and broiler meat. No Salmonella isolate was resistant to third-generation cephalosporins. In conclusion, meat imported into Sweden, broiler meat in particular, is a potential source of human exposure to ESBL- and pAmpC-producing E. coli.

  14. Usefulness of phenotypic and genotypic methods for metallo-beta-lactamases detection in carbapenem-resistant Acinetobacter baumannii strains

    OpenAIRE

    2013-01-01

    Background Acinetobacter baumannii is an opportunistic microorganism with an increasing role in nosocomial outbreaks. For the last 2 decades, a growing number of carbapenem-resistant A. baumannii strains have been identified, including the metallo-beta-lactamases (MBLs) producers. The study aimed to investigate the genetic relatedness of, and MBLs production among, a collection of A. baumannii isolates from Poland. Material/Methods This study involved 78 clinical isolates of carbapenem-resist...

  15. Screening of some medicinal plants from cameroon for beta-lactamase inhibitory activity.

    Science.gov (United States)

    Gangoué-Piéboji, Joseph; Baurin, Stéphane; Frère, Jean-Marie; Ngassam, Pierre; Ngameni, Bathelemy; Azebaze, Anatole; Pegnyemb, Dieudonné Emmanuel; Watchueng, Jean; Goffin, Colette; Galleni, Moreno

    2007-03-01

    In efforts to find new bioactive beta-lactamase inhibitors, this study investigated 16 Cameroonian plants belonging to 10 families which were evaluated for anti-beta-lactamase activity. The investigation showed that extracts 2, 6, 3 and 5 of the 16 plants investigated presented interesting in vitro beta-lactamase inhibition (over 90%), respectively, of the beta-lactamases TEM-1, OXA-10, IMP-1 and P99. These extracts were from Mammea africana (all beta-lactamases), Garcinia lucida, G. kola (OXA-10, IMP-1 and P99), Bridelia micrantha (OXA-10, P99), Ochna afzelii (OXA-10, P99), Prunus africana (IMP-1) and Adenia lobata (TEM-1). After elimination of tannins (according to the European Pharmacopoeia) the extracts from B. micrantha, G. lucida and M. africana were tested further for their anti-beta-lactamase activity. The extracts from B. micrantha and G. lucida exhibited potent inhibitory activity, respectively, of beta-lactamase OXA-10 (IC(50) = 0.02 mg/mL) and P99 (IC(50) = 0.01 mg/mL). The anti-beta-lactamase activity of M. africana extract was weak. The isolation and the structural elucidation of the active constituents of G. lucida and B. micrantha will provide useful leads in the development of beta-lactamase inhibitors.

  16. Purification and properties of inducible penicillin beta-lactamase isolated from Pseudomonas maltophilia.

    OpenAIRE

    Saino, Y; Kobayashi, F; Inoue, M.; Mitsuhashi, S

    1982-01-01

    Two types of beta-lactamase were found in the cell-free extract from Pseudomonas maltophilia GN12873. One was an inducible penicillin beta-lactamase, and the other was an inducible cephalosporin beta-lactamase. The purified penicillin beta-lactamase gave a single protein band on polyacrylamide gel electrophoresis. The isoelectric point was 6.9, and the approximate molecular weight was 118,000 by gel filtration and 26,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting...

  17. Beta-lactamase induction and cell wall metabolism in Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Ximin eZeng

    2013-05-01

    Full Text Available Production of beta-lactamases, the enzymes that degrade beta-lactam antibiotics, is the most widespread and threatening mechanism of antibiotic resistance. In the past, extensive research has focused on the structure, function, and ecology of beta-lactamases while limited efforts were placed on the regulatory mechanisms of beta-lactamases. Recently, increasing evidence demonstrate a direct link between beta-lactamase induction and cell wall metabolism in Gram-negative bacteria. Specifically, expression of beta-lactamase could be induced by the liberated murein fragments, such as muropeptides. This article summarizes current knowledge on cell wall metabolism, beta-lactam, and beta lactamases. In particular, we comprehensively reviewed recent studies on the beta-lactamase induction by muropeptides via two major molecular mechanisms (the AmpG-AmpR-AmpC pathway and BlrAB-like two-component regulatory system in Gram-negative bacteria. The signaling pathways for beta-lactamase induction offer a broad array of promising targets for the discovery of new antibacterial drugs used for combination therapies. Therefore, to develop effective mitigation strategies against the widespread beta-lactam resistance, examination of the molecular basis of beta-lactamase induction by cell wall fragment is highly warranted.

  18. Prevalence, characterization and clinical significance of Klebsiella pneumoniae carbapenemase (KPC producing Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    : Sarita Nayak, Suman Singh, Soeb Jankhwala, Riddhi Pradhan

    2014-11-01

    Full Text Available Klebsiella peumoniae, a capsulated gram negative bacillus is responsible for causing life threatening infections in humans. Carbapenems are the drug of choice for serious infection caused by multidrug resistant Klebsiella pneumoniae. The emergence of carbapenem resistance has made it extremely difficult to treat such infections resulting in significant morbidity and mortality. Aims: To study the prevalence of carbapenem resistance using ertapenem as a marker and to detect Klebsiella pneumoniae Carbapenemase (KPC producing Klebsiella pneumoniae as a mechanism of resistance. Material and Methods: The study included 102 patients from which Klebsiella pneumoniae isolated. Identification and antibiotic susceptibility testing of Klebsiella pneumoniae was performed on miniAPI (Analytical Profile Index, Semiautomated bacterial identification system according to Clinical and Laboratory Standards Institute (CLSI guidelines of 2011. The modified Hodge test was performed for detection of Carbapenemase production. Patient’s clinical and demographic details along with risk factors and co-morbid conditions, type of response to antimicrobial therapy and mortality were collected. Results: The prevalence of carbapenem resistance was found to be 30.41% with 16.6% KPC producing Klebsiella pneumoniae. The co-morbid conditions like immunocompromised state (p =0.042, prior antibiotics therapy (p=0.047, previous hospitalization (p =0.021, intensive care unit stay (p=0.047 and use of indwelling devices (p =0.013 were found to be significantly associated with carbapenem resistance. Adverse clinical outcomes (death or worsening among patients infected with ertapenem resistant patients was found to be statistically significant than ertapenem sensitive strains (p =0.008. Conclusions: A high degree of carbapenem resistance in present study is alarming and poses therapeutic dilemmas for clinicians. Initiating timely and appropriate infection control measures along with a

  19. Constitutive high expression of chromosomal beta-lactamase in Pseudomonas aeruginosa caused by a new insertion sequence (IS1669) located in ampD

    DEFF Research Database (Denmark)

    Bagge, N.; Ciofu, O.; Hentzer, Morten;

    2002-01-01

    resistant, constitutive beta-lactamase-producing variant contained no mutations in ampD, but a point mutation was observed in ampR, resulting in an Asp-135-->Asn change. An identical mutation of AmpR in Enterobacter cloacae has been reported to cause a 450-fold higher AmpC expression. However, in many...

  20. Influence of beta-lactamase inhibitors on the activity of oxacillin against methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Chang, S C; Hsieh, W C; Luh, K T

    1995-02-01

    We studied the in vitro susceptibility to oxacillin of 46 isolates of methicillin-resistant Staphylococcus aureus (MRSA) isolates with a minimum inhibitory concentration (MIC) > 8 micrograms/ml of oxacillin, with and without adding clavulanic acid, sulbactam, or tazobactam in three different concentrations (2, 4, and 8 micrograms/ml). All 46 strains were found by the rapid chromogenic cephalosporin method to be beta-lactamase producers. For those strains with low-level resistance (MIC of 16 or 32 micrograms/ml), the MICs of oxacillin decreased four- to 32-fold and two- to 32-fold after adding sulbactam and tazobactam, respectively. For those with high-level resistance (MIC of > or = 64 micrograms/ml), the MICs either did not change or decreased only two-fold after we added one of three beta-lactamase inhibitors. The results suggest that beta-lactamase production probably plays a role in resistance to oxacillin in those MRSA strains of low-level oxacillin resistance.

  1. Nanomolar Inhibitors of AmpC [beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Morandi, Federica; Caselli, Emilia; Morandi, Stefania; Focia, Pamela J.; Blazquez, Jesus; Shoichet, Brian K.; Prati, Fabio (Degali); (NIH); (NWU); (UCSF)

    2010-03-08

    {beta}-lactamases are the most widespread resistance mechanism to {beta}-lactam antibiotics, such as the penicillins and the cephalosporins. In an effort to combat these enzymes, a combination of stereoselective organic synthesis, enzymology, microbiology, and X-ray crystallography was used to design and evaluate new carboxyphenyl-glycylboronic acid transition-state analogue inhibitors of the class C {beta}-lactamase AmpC. The new compounds improve inhibition by over 2 orders of magnitude compared to analogous glycylboronic acids, with K{sub i} values as low as 1 nM. On the basis of the differential binding of different analogues, the introduced carboxylate alone contributes about 2.1 kcal/mol in affinity. This carboxylate corresponds to the ubiquitous C3(4)' carboxylate of {beta}-lactams, and this energy represents the first thermodynamic measurement of the importance of this group in molecular recognition by class C {beta}-lactamases. The structures of AmpC in complex with two of these inhibitors were determined by X-ray crystallography at 1.72 and 1.83 {angstrom} resolution. These structures suggest a structural basis for the high affinity of the new compounds and provide templates for further design. The highest affinity inhibitor was 5 orders of magnitude more selective for AmpC than for characteristic serine proteases, such as chymotrypsin. This inhibitor reversed the resistance of clinical pathogens to the third generation cephalosporin ceftazidime; it may serve as a lead compound for drug discovery to combat bacterial resistance to {beta}-lactam antibiotics.

  2. Constitutive high expression of chromosomal beta-lactamase in Pseudomonas aeruginosa caused by a new insertion sequence (IS1669) located in ampD

    DEFF Research Database (Denmark)

    Bagge, Niels; Ciofu, Oana; Hentzer, Morten

    2002-01-01

    The expression of chromosomal AmpC beta-lactamase in Pseudomonas aeruginosa is negatively regulated by the activity of an amidase, AmpD. In the present study we examined resistant clinical P. aeruginosa strains and several resistant variants isolated from in vivo and in vitro biofilms for mutations...... in the expression of high levels of AmpC beta-lactamase. Complementation of these isolates with ampD from the reference P. aeruginosa strain PAO1 caused a dramatic decrease in the expression of AmpC beta-lactamase and a parallel decrease of the MIC of ceftazidime to a level comparable to that of PAO1. One highly...... resistant, constitutive beta-lactamase-producing variant contained no mutations in ampD, but a point mutation was observed in ampR, resulting in an Asp-135-->Asn change. An identical mutation of AmpR in Enterobacter cloacae has been reported to cause a 450-fold higher AmpC expression. However, in many...

  3. Antibiogram Studies and Extended Spectrum Beta-lactamase Activity Profile of Salmonella-like Species Isolated from Poultry Soil of the University of Uyo, Nigeria

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    Ikpeme, E. M.

    2012-01-01

    Full Text Available Aims: The contribution of beta-lactamase activity of various bacterial species to the increased antimicrobial resistance being experienced worldwide is very scanty in the literature. This study was undertaken to investigate the antibiotic resistance pattern (antibiogram of Salmonella-like bacterial species against some antibiotics, and the role beta-lactamase assumably produced by the Salmonella-like species, played in producing resistance.Methodology and Results: The antimicrobial sensitivity test and the beta-lactamase test of the Salmonella-like species were carried out using the methods of Kirby Bauer sensitivity test and the Double Disk Synergy test respectively, following isolation and identification of the organisms from poultry soil. Results revealed that Salmonella-like species were most highly resistant to Nalidixic acid (20, 66.66%, followed by Tetracycline (19, 63.33%, Cotrimoxazole, Amoxicillin and Augmentin (18, 60%, while the least was Ofloxacin (8, 26.66%. Multiple resistance of 4 or more antibiotics among the isolates from the soil outside the broilers enclosure was observed, while there was a significant difference (P <0.05 between poultry soil and control soil. This implied that the antibiotics with the highest resistance were most often applied to the birds, the droppings of which contaminated the soil. The resistant pattern of the isolates from the control soil is lower than that from the poultry soil. Extended Spectrum Beta-lactamase activity was expressed by all the isolates against Cefotazime, while the least resistance was against mostly Cefotazime.Conclusion, significance and impact of study: It is concluded that there is a widespread Beta-lactamase activity causing antibiotic resistance by many species of bacteria as well as poultry Salmonella, thus exacerbating the global problem of antibiotic resistance and a serious health related implication for antibiotic use in poultry.

  4. The metallo-. beta. -lactamases of Bacillus cereus 5/B/6: Expression in Echierichia coli, purification, and characterization of the purified recombinant enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, R.W.; Clark, S.D.; Hilliard, N.P.; Harman, J.G. (Texas Tech Univ., Lubbock (United States))

    1991-03-11

    The gene for the B. cereus 5/B/6 metallo-{beta}-lactamase was subcloned into the E. coli expression vector pRE-2. The resultant recombinants displayed a low level of enzyme activity. Generation of a site-directed mutant of the {beta}-lactamase gene containing both a Nde I site and an initiator codon allowed us to separate the {beta}-lactamase structural gene from its leader sequence. When only the structural gene was cloned into pRE-2, the B. cereus {beta}-lactamase activity was increased 9.8-fold. Purification of the recombinant enzyme from E. coli by ultracentrifugation, gel filtration, anion and cation exchange chromatography allowed the enzyme to be purified to homogeneity with an overall yield of 87%. The properties of the recombinant enzyme were identical to those of the B. cereus enzyme; e.g., the electrophoretic mobilities of the purified recombinant enzyme and the purified B. cereus enzyme were identical in both native and SDS gel electrophoresis As with the B. cereus enzyme, K{sub m} and V{sub max} for the recombinant enzyme are 0.39 mM and 1,333 units/mg protein, respectively. Likewise, the Co(II)-reconstituted recombinant enzyme has electronic spectra with maxima at 347, 551, 617 and 646 nm and extinction coefficients of 900, 250, 173 and 150 M{sup {minus}1} cm{sup {minus}1}, respectively. This heterologous construct and purification scheme will be used to produce and purify site-directed mutant proteins for use in exploring the reaction mechanisms of B. cereus metallo-{beta}-lactamases.

  5. Emergence of DHA-1-producing Klebsiella spp. in the Parisian region: genetic organization of the ampC and ampR genes originating from Morganella morganii.

    Science.gov (United States)

    Verdet, Charlotte; Benzerara, Yahia; Gautier, Valérie; Adam, Olivier; Ould-Hocine, Zahia; Arlet, Guillaume

    2006-02-01

    Eleven Klebsiella pneumoniae clinical isolates and one Klebsiella oxytoca clinical isolate showing various pulsed-field gel electrophoresis types and producing an inducible DHA-1 class C beta-lactamase were isolated in the Parisian region between 1998 and 2003. The aim of this study was to compare the genetic organization of the bla(DHA-1) genes in this collection of clinical isolates. In four isolates, the Morganella morganii-derived genomic region containing bla(DHA-1) was inserted in an entire complex sul1-type integron, including a region common to In6-In7 (CR1), as previously described in a bla(DHA-1)-producing Salmonella enterica serovar Enteritidis KF92 isolate from Saudi Arabia in 1992. Different gene cassette arrays were characterized in each of these integrons. In two of them, an additional 10-kb fragment was inserted between the CR1 and the M. morganii-derived region and was similar to the sap (ABC transporter family) and psp (phage shock protein) operons originated from Salmonella enterica serovar Typhimurium. The length of the M. morganii region was variable, suggesting that several independent recombination events have occurred and that open reading frame orf513 encodes a recombinase involved in the mobilization of the resistance genes. The genetic organization of bla(DHA-1) was identical in the eight other isolates. This structure is likely derived from a complex integron following the insertion of IS26, leading to the deletion of the first part of integron. The horizontal transfer of one plasmid carrying that truncated integron was shown for seven of these isolates.

  6. STUDY OF URINARY ISOLATES WITH REFERENCE TO EXTENDE D SPECTRUM BETA LACTAMASES DETECTION AND ANTIBIOGRAM

    Directory of Open Access Journals (Sweden)

    Abhijit

    2013-03-01

    Full Text Available ABSTRACT: BACKGROUND: Extended spectrum beta lactamases continue to be ma jor problem in clinical setups world over, conferring resistance to extended spectrum cephalosporins and are associated with significant morbidity and morta lity. Urinary tract infections (UTIs are one of the most common infectious diseases encountered in the clinical practice. Extended spectrum beta lactamases (ESBLs production in gram negative bacteria, have emerged as a major problem in hospitalized as well as community based pat ients. ESBLs producing bacteria may not be detected by routine disc diffusion susceptibility test, leading to inappropriate use of antibiotics and treatment failure. The objective of this study was to determine the resistance patterns of the micro-organisms isolated from cases of UTI and to detect ESBLs production in gram negative bacteria. METHODS: Urinary isolates from symptomatic UTI cases (both i n patients and out patients attending the, Kesarsal Me dical College and Hospital Ahmadabad were identified by conventional methods. Antimicrob ial susceptibility testing was performed by Kirby Bauer's disc diffusion method gram negative i solates resistant to third generation cephalosporins were tested for ESBL production by two methods. RESULTS: Number of urinary isolates from patients with symptomatic UTI was 350 o ver a study period of one year. E.coli was the predominant isolate (57.7% both in IPD and OPD patients. A total of 171 gram negative isolates resistant to third generation cephalosporins were tested for ESBL production by two methods- Modified Double Disc Synergy Test (CLSI P henotypic Confirmatory Test (PCT. ESBL production was seen in 36 (21.05% isolates. Maximum ESBL production was seen in K. pneumoniae (22.41% isolates followed by E.coli (13.26%. CONCLUSION: This study showed E.coli to be the predominant urinary pathogen isolate d from UTI cases. Overall incidence of ESBL producing microorganisms was 21.05%.

  7. Thermodynamic Cycle Analysis and Inhibitor Design against Beta-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Tomer A.; Minasov, George; Morandi, Stefania; Prati, Fabio; Shoichet, Brian K. (Degali); (UCSF)

    2010-03-08

    {beta}-Lactamases are the most widespread resistance mechanism to {beta}-lactam antibiotics, such as the penicillins and cephalosporins. Transition-state analogues that bind to the enzymes with nanomolar affinities have been introduced in an effort to reverse the resistance conferred by these enzymes. To understand the origins of this affinity, and to guide design of future inhibitors, double-mutant thermodynamic cycle experiments were undertaken. An unexpected hydrogen bond between the nonconserved Asn289 and a key inhibitor carboxylate was observed in the X-ray crystal structure of a 1 nM inhibitor (compound 1) in complex with AmpC {beta}-lactamase. To investigate the energy of this hydrogen bond, the mutant enzyme N289A was made, as was an analogue of 1 that lacked the carboxylate (compound 2). The differential affinity of the four different protein and analogue complexes indicates that the carboxylate-amide hydrogen bond contributes 1.7 kcal/mol to overall binding affinity. Synthesis of an analogue of 1 where the carboxylate was replaced with an aldehyde led to an inhibitor that lost all this hydrogen bond energy, consistent with the importance of the ionic nature of this hydrogen bond. To investigate the structural bases of these energies, X-ray crystal structures of N289A/1 and N289A/2 were determined to 1.49 and 1.39 {angstrom}, respectively. These structures suggest that no significant rearrangement occurs in the mutant versus the wild-type complexes with both compounds. The mutant enzymes L119A and L293A were made to investigate the interaction between a phenyl ring in 1 and these residues. Whereas deletion of the phenyl itself diminishes affinity by 5-fold, the double-mutant cycles suggest that this energy does not come through interaction with the leucines, despite the close contact in the structure. The energies of these interactions provide key information for the design of improved inhibitors against {beta}-lactamases. The high magnitude of the ion

  8. Characterization of Extended spectrum beta-lactamases (ESBL)-producing Escherichia coli obtained from Danish pigs, pig farmers and their families from farms with high or no consumption of 3rd or 4th generation cephalosporins

    DEFF Research Database (Denmark)

    Hammerum, Anette M.; Larsen, Jesper; Dalhoff Andersen, Vibe;

    2014-01-01

    Objectives: To compare and characterize extended-spectrum b-lactamase (ESBL)-producing Escherichia coli from pigsties, pig farmers and their families on farms with previous high or no use of third- or fourth-generation cephalosporins. Methods: Twenty farms with no third- or fourth-generation ceph...

  9. Pharmacodynamics of Finafloxacin, Ciprofloxacin and Levofloxacin in Serum and Urine against TEM- and SHV-type Extended-Spectrum Beta-Lactamase Producing Enterobacteriaceae Isolated from Patients with Urinary Tract Infections.

    Science.gov (United States)

    Dalhoff, A; Schubert, S; Vente, A

    2017-02-13

    Background: Pharmacodynamics of finafloxacin, ciprofloxacin and levofloxacin against ESBL-producing Enterobacteriaceae were compared. As quinolones loose activity in acidic media and in particular in urine, their activities were tested in parallel under conventional conditions and in acidic artificial urine.Methods: TEM- and SHV-type ESBL-producing E. coli and K. pneumoniae and their wild-type counterparts were exposed in a modified Grasso model to serum- and urine-concentrations following oral doses of finafloxacin 800mg qd, immediate- release ciprofloxacin 500mg bid, extended release ciprofloxacin-XR 1000mg qd, levofloxacin 500mg qd, or levofloxacin 750mg qd. Urine-concentrations were fitted by compartmental modeling. Bacteria were cultivated in Mueller-Hinton-Broth (MHB) pH 7.2 or 5.8 or in artificial urine pH 5.8. Bacteria were counted two-hourly till 10h and at 24h; the areas under the bacterial count versus time curves were calculated.Results: Finafloxacin eliminated all strains within 2h under any of the conditions studied. Any of the ciprofloxacin or levofloxacin doses was highly active against wild-type strains in MHB, pH 7.2 but lost activity at pH 5.8 and in particular in urine. Viable counts of ESBL-producers were reduced for 6-8h by 3 log10 titers but bacteria regrew thereafter. Ciprofloxacin and levofloxacin were almost inactive against the SVH-producer grown in artificial urine.Conclusions: The use of artificial urine but not conventional media in pharmacodynamic models may mirror the physiology of UTIs more closely. In contrast to ciprofloxacin and levofloxacin, finafloxacin gained activity in this model at an acidic pH and maintained activity in artificial urine and was active against TEM- and SHV-producers.

  10. Docking and scoring of metallo-beta-lactamases inhibitors

    DEFF Research Database (Denmark)

    Olsen, Lars; Pettersson, Ingrid; Hemmingsen, Lars

    2004-01-01

    The performance of the AutoDock, GOLD and FlexX docking programs was evaluated for docking of dicarboxylic acid inhibitors into metallo-beta-lactamases (MBLs). GOLD provided the best overall performance, with RMSDs between experimental and docked structures of 1.8-2.6 A and a good correlation...... between the experimentally determined MBL-inhibitor affinities and the GOLD scores. GOLD was selected for a test including a broad spectrum of inhibitors for which experimental MBL-inhibitor binding affinities are available. This study revealed that (1) for most compound classes (dicarboxylic acids...... and descriptors associated with binding of the IMP-1 inhibitors to the enzyme. The external Q2 for the test set is 0.73. This final model for prediction of IMP-1 MBL-inhibitor affinity handled all known classes of MBL-inhibitors, except small sulphur compounds....

  11. KPC-producing Klebsiella pneumoniae, finally targeting Turkey

    Directory of Open Access Journals (Sweden)

    J. Labarca

    2014-03-01

    Full Text Available We report here the first identification of the worldwide spread of Klebsiella pneumoniae carbapenemase-2-producing and carbapenem-resistant K. pneumoniae clone ST258 in Turkey, a country where the distantly-related carbapenemase OXA-48 is known to be endemic. Worryingly, this isolate was also resistant to colistin, now considered to be the last-resort antibiotic for carbapenem-resistant isolates.

  12. Determinants of binding affinity and specificity for the interaction of TEM-1 and SME-1 beta-lactamase with beta-lactamase inhibitory protein.

    Science.gov (United States)

    Zhang, Zhen; Palzkill, Timothy

    2003-11-14

    The hydrolysis of beta-lactam antibiotics by class A beta-lactamases is a common cause of bacterial resistance to these agents. The beta-lactamase inhibitory protein (BLIP) is able to bind and inhibit several class A beta-lactamases, including TEM-1 beta-lactamase and SME-1 beta-lactamase. Although the TEM-1 and SME-1 enzymes share 33% amino acid sequence identity and a similar fold, they differ substantially in surface electrostatic properties and the conformation of a loop-helix region that BLIP binds. Alanine-scanning mutagenesis was performed to identify the residues on BLIP that contribute to its binding affinity for each of these enzymes. The results indicate that the sequence requirements for binding are similar for both enzymes with most of the binding free energy provided by two patches of aromatic residues on the surface of BLIP. Polar residues such as several serines in the interface do not make significant contributions to affinity for either enzyme. In addition, the specificity of binding is significantly altered by mutation of two charged residues, Glu73 and Lys74, that are buried in the structure of the TEM-1.BLIP complex as well as by residues located on two loops that insert into the active site pocket. Based on the results, a E73A/Y50A double mutant was constructed that exhibited a 220,000-fold change in binding specificity for the TEM-1 versus SME-1 enzymes.

  13. Klebsiella pneumoniae produces no histamine: Raoultella planticola and Raoultella ornithinolytica strains are histamine producers.

    Science.gov (United States)

    Kanki, Masashi; Yoda, Tomoko; Tsukamoto, Teizo; Shibata, Tadayoshi

    2002-07-01

    Histamine fish poisoning is caused by histamine-producing bacteria (HPB). Klebsiella pneumoniae and Klebsiella oxytoca are the best-known HPB in fish. However, 22 strains of HPB from fish first identified as K. pneumoniae or K. oxytoca by commercialized systems were later correctly identified as Raoultella planticola (formerly Klebsiella planticola) by additional tests. Similarly, five strains of Raoultella ornithinolytica (formerly Klebsiella ornithinolytica) were isolated from fish as new HPB. R. planticola and R. ornithinolytica strains were equal in their histamine-producing capabilities and were determined to possess the hdc genes, encoding histidine decarboxylase. On the other hand, a collection of 61 strains of K. pneumoniae and 18 strains of K. oxytoca produced no histamine.

  14. Extended-spectrum beta-lactamases among Enterobacteriaceae isolated in a public hospital in Brazil Beta-lactamases de espectro estendido em Enterobacteriaceae isoladas de Hospital Público no Brasil

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    Milena Dropa

    2009-08-01

    Full Text Available Extended-spectrum β-lactamases (ESBL in enterobacteria are recognized worldwide as a great hospital problem. In this study, 127 ESBL-producing Enterobacteriaceae isolated in one year from inpatients and outpatients at a public teaching hospital at São Paulo, Brazil, were submitted to analysis by PCR with specific primers for blaSHV, blaTEM and blaCTX-M genes. From the 127 isolates, 96 (75.6% Klebsiella pneumoniae, 12 (9.3% Escherichia coli, 8 (6.2% Morganella morganii, 3 (2.3% Proteus mirabilis, 2 (1.6% Klebsiella oxytoca, 2 (1.6% Providencia rettgeri, 2 (1.6% Providencia stuartti, 1 (0.8% Enterobacter aerogenes and 1 (0.8% Enterobacter cloacae were identified as ESBL producers. BlaSHV, blaTEM and blaCTX-M were detected in 63%, 17.3% and 33.9% strains, respectively. Pulsed field gel eletrophoresis genotyping of K. pneumoniae revealed four main molecular patterns and 29 unrelated profiles. PCR results showed a high variety of ESBL groups among strains, in nine different species. The results suggest the spread of resistance genes among genetically different strains of ESBL-producing K. pneumoniae in some hospital wards, and also that some strongly related strains were identified in different hospital wards, suggesting clonal spread in the institutional environment.Beta-lactamases de espectro estendido (ESBL em enterobactérias são reconhecidas mundialmente como um grande problema hospitalar. Neste estudo, 127 Enterobacteriaceae produtoras de ESBL isoladas por um ano, de pacientes internados e ambulatoriais de um hospital público de ensino em São Paulo, Brasil, foram submetidas à análise pela PCR com iniciadores específicos para os genes blaSHV, blaTEM e blaCTX-M. Dos 127 isolados, 96 (75,6% K. pneumoniae, 12 (9,3% E. coli, 8 (6,2% M. morganii, 3 (2,3% Proteus mirabilis, 2 (1,6% Klebsiella oxytoca, 2 (1,6% Providencia rettgeri, 2 (1,6% Providencia stuartti, 1 (0,8% Enterobacter aerogenes e 1 (0,8% Enterobacter cloacae foram identificados

  15. Accumulation of plasmid-mediated fluoroquinolone resistance genes, qepA and qnrS1, in Enterobacter aerogenes co-producing RmtB and class A beta-lactamase LAP-1.

    Science.gov (United States)

    Park, Yeon-Joon; Yu, Jin Kyung; Kim, Sang-Il; Lee, Kyungwon; Arakawa, Yoshichika

    2009-01-01

    A new plasmid-mediated fluoroquinolone efflux pump gene, qepA, is known to be associated with the rmtB gene, which confers high-level resistance to aminoglycosides. We investigated the qepA gene in 573 AmpC-producing Enterobacteriaceae including one Citrobacter freundii known to harbor rmtB. Of them, two clonally unrelated E. aerogenes harbored qepA. Both isolates co-harbored rmtB, qnrS1, qepA, and bla(LAP-1) on an IncFI type plasmid. The qepA was flanked by two copies of IS26 containing ISCR3C, tnpA, tnpR, bla(TEM), and rmtB. The qnrS1 and bla(LAP-1) were located upstream of qepA. All the resistance determinants (qepA, qnrS1, rmtB, and bla(LAP-1)) were co-transferred to E. coli J53 by filter mating from both isolates. Although the prevalence of qepA is currently low, considering the presence of ISCR3C and the possibility of co-selection and co-transferability of plasmids, more active surveillance for these multi-drug resistant bacteria and prudent use of antimicrobials are needed.

  16. SME-type carbapenem-hydrolyzing class A beta-lactamases from geographically diverse Serratia marcescens strains.

    Science.gov (United States)

    Queenan, A M; Torres-Viera, C; Gold, H S; Carmeli, Y; Eliopoulos, G M; Moellering, R C; Quinn, J P; Hindler, J; Medeiros, A A; Bush, K

    2000-11-01

    Three sets of carbapenem-resistant Serratia marcescens isolates have been identified in the United States: 1 isolate in Minnesota in 1985 (before approval of carbapenems for clinical use), 5 isolates in Los Angeles (University of California at Los Angeles [UCLA]) in 1992, and 19 isolates in Boston from 1994 to 1999. All isolates tested produced two beta-lactamases, an AmpC-type enzyme with pI values of 8.6 to 9.0 and one with a pI value of approximately 9.5. The enzyme with the higher pI in each strain hydrolyzed carbapenems and was not inhibited by EDTA, similar to the chromosomal class A SME-1 beta-lactamase isolated from the 1982 London strain S. marcescens S6. The genes encoding the carbapenem-hydrolyzing enzymes were cloned in Escherichia coli and sequenced. The enzyme from the Minnesota isolate had an amino acid sequence identical to that of SME-1. The isolates from Boston and UCLA produced SME-2, an enzyme with a single amino acid change relative to SME-1, a substitution from valine to glutamine at position 207. Purified SME enzymes from the U. S. isolates had beta-lactam hydrolysis profiles similar to that of the London SME-1 enzyme. Pulsed-field gel electrophoresis analysis revealed that the isolates showed some similarity but differed by at least three genetic events. In conclusion, a family of rare class A carbapenem-hydrolyzing beta-lactamases first described in London has now been identified in S. marcescens isolates across the United States.

  17. Prevalence PER and VEB beta-lactamase Genes among Acinetobacter baumannii Isolated from Patients in Tehran by PCR

    Directory of Open Access Journals (Sweden)

    Abbas Nazari Monazam

    2014-12-01

    Full Text Available Background and Aim: According to numerous reports of infections caused by spectrum beta lactamases (ESBLs producing Acinetobacter baumannii in our country in recent years, this study was performed to define the antibiotic susceptibility patterns and detect the prevalence PER  and VEB beta-lactamase genes among  A.baumannii isolated from patients in Tehran by PCR. Materials and Methods: 100 A.baumannii clinical isolates collected from various hospitals in Tehran during a year, using special culture media and biochemical tests were identified. The antibiograms of the isolates against 11 antibiotics by disk diffusion method (Disk diffusion according to Clinical and Laboratory Standards Institute (CLSI guidelines was performed. Then minimum inhibitory concentrations (MIC was determined for cefepime and ceftazidime and for the identification of ESBL-producing strains was used in combination disk method, and finally to assess the prevalence of PER and VEB beta-lactamase genes using specific primers PCR was performed. Results: Antibiograms results showed that the greatest resistance to the antibiotics amikacin, cefepime, and less resistance to polymyxin B were obtained. Rates of multi-drug resistant strains of about 70% was achieved. Of the isolates studied, the MIC of ceftazidime in 84% and for cefepime in 91% were ≥ 128 μg/ml. The results of the combined-disk test demonstrated that 20% of samples were ESBL positive. The PCR results showed that 47% and 32% of our isolates had PER and VEB genes respectively. Conclusions: Regarding to existence of PER and VEB genes in this bacterium and possibility of transformation of these genes to the other bacteria, reconsideration in antibiotics consumption patterns and more attention to nosocomial infections control criteria are inevitable.

  18. TLA-1: a new plasmid-mediated extended-spectrum beta-lactamase from Escherichia coli.

    Science.gov (United States)

    Silva, J; Aguilar, C; Ayala, G; Estrada, M A; Garza-Ramos, U; Lara-Lemus, R; Ledezma, L

    2000-04-01

    Escherichia coli R170, isolated from the urine of an infected patient, was resistant to expanded-spectrum cephalosporins, aztreonam, ciprofloxacin, and ofloxacin but was susceptible to amikacin, cefotetan, and imipenem. This particular strain contained three different plasmids that encoded two beta-lactamases with pIs of 7.0 and 9.0. Resistance to cefotaxime, ceftazidime, aztreonam, trimethoprim, and sulfamethoxazole was transferred by conjugation from E. coli R170 to E. coli J53-2. The transferred plasmid, RZA92, which encoded a single beta-lactamase, was 150 kb in length. The cefotaxime resistance gene that encodes the TLA-1 beta-lactamase (pI 9.0) was cloned from the transconjugant by transformation to E. coli DH5alpha. Sequencing of the bla(TLA-1) gene revealed an open reading frame of 906 bp, which corresponded to 301 amino acid residues, including motifs common to class A beta-lactamases: (70)SXXK, (130)SDN, and (234)KTG. The amino acid sequence of TLA-1 shared 50% identity with the CME-1 chromosomal class A beta-lactamase from Chryseobacterium (Flavobacterium) meningosepticum; 48.8% identity with the VEB-1 class A beta-lactamase from E. coli; 40 to 42% identity with CblA of Bacteroides uniformis, PER-1 of Pseudomonas aeruginosa, and PER-2 of Salmonella typhimurium; and 39% identity with CepA of Bacteroides fragilis. The partially purified TLA-1 beta-lactamase had a molecular mass of 31.4 kDa and a pI of 9.0 and preferentially hydrolyzed cephaloridine, cefotaxime, cephalothin, benzylpenicillin, and ceftazidime. The enzyme was markedly inhibited by sulbactam, tazobactam, and clavulanic acid. TLA-1 is a new extended-spectrum beta-lactamase of Ambler class A.

  19. 产CTX-M型ESBLS大肠埃希菌传播的分子机制研究%Study on the molecular mechanism of the dissemination of a novel CTX-M-like extended spectrum beta-lactamase-producing Escherichia coil

    Institute of Scientific and Technical Information of China (English)

    江洁华; 廖伟娇; 易建云; 陈涛; 苏秀馨; 李翊泉; 徐韫健

    2008-01-01

    Objective To investigate the distribution of the CTX-M- extended spectrum beta-lactamase (ESBLs) producing Esche- richia coli(ECO) and the molecular mechanism of dissemination. Methods To analyze the drug resistance of the 43 isolates, Kirby-Bauer susceptibility method was used. Multiple polymeraso chain reaction (PCR) was used to amplify the gene of ESBLs, AmpC, full length of blaCTX-M-like gene, insertion sequence (IS) ISEcp1B, IS903 , IS26 and integron I. NEST-PCR was used to detect if the beta-lactamase gene lo- cated in the integron I. The product of full length of bla-CTX-M like gone amplified by PCR was sequenced. Results Susceptibility test showed the resistance from high to low in turn was Ampicillin (97.68%), Coftriaxone (67.44 % ), piperacillin(65.12 % ), Cefotaxime (62.79 % ) ,Coftasidime(58.14% ), Cofasolin(55.81% ), Cofepime (53.49%), Cefexitin(51.16%), ciprofloxacin (44. 19% ), Aztreo- nam(41.86% ), Cefoperasone/Sulbactam ( 20.93% ), Amikacin (0% ), Imipenem (0% ), respectively. ECO was susceptive to Imipenem. CTX-M-G1 was found in 25 strains of ECO , TEM, SHV, CTX-M-G1, ISEcp1B, and integron I were found in the nine isolates. IS903 were found in ECO 3 and 5, and IS26 was found in ECO 3. In ECO 3 and 5, blaCTX-M-like was flanked upstream by ISEcp1B element that provided -35 and -10 promoter sequences and a right inverted repeat (IRR) recognized by transposase, downstream by IS903 provided an inverted re- peat, ISEcp1 B and IS903 composed the complex transpeson. Conclusion ISEcplB may drive the expression and dissemination of blaCTX-M-like gene at a high level.%目的 了解CTX-M型超广谱β-内酰胺酶(ESBLs)在大肠埃希菌中的分布及传播的分子机制.方法 用Kirby-Bauer(K-B)药敏法分析43株大肠埃希菌的耐药性;用多重聚合酶链式反应(PCR)扩增ESBLs、AmpC、ISEcp1 B、IS903、IS26等插入序列及I类整合子;用套式PCR在I类整合子寻找β-内酰胺酶基因盒,扩增CTX-M型ESBLs全序列并测序.结果

  20. A ten-year surveillance study of carbapenemase-producing Klebsiella pneumoniae in a tertiary care Greek university hospital: predominance of KPC- over VIM- or NDM-producing isolates.

    Science.gov (United States)

    Spyropoulou, Aikaterini; Papadimitriou-Olivgeris, Matthaios; Bartzavali, Christina; Vamvakopoulou, Sophia; Marangos, Markos; Spiliopoulou, Iris; Anastassiou, Evangelos D; Christofidou, Myrto

    2016-03-01

    Resistance patterns and carbapenemase gene presence among Klebsiella pneumoniae isolates from the University General Hospital of Patras, Greece during a ten-year period were analysed under a surveillance programme for multi-drug-resistant bacteria. From 2005 to 2014, K. pneumoniae isolates from clinically significant specimens were identified by the Vitek 2 Advanced Expert System. Antibiotic susceptibility testing was performed by the agar disc diffusion method and Etest. The strains were tested for the presence of blaVIM, blaIMP, blaKPC, blaNDM and blaOXA-48 genes by PCR. PFGE of chromosomal Xbal DNA digests was performed. A total of 3449 K. pneumoniae isolates were recovered during the last decade. Among them, 1668 (48 %) were carbapenemase-producing: 1333 (80%) K. pneumoniae carbapenemase (KPC)-, 286 (17%) Verona imipenemase (VIM), 45 (3%) KPC- and VIM-, and four New Delhi metallo-beta-lactamase (NDM)-producing. Their resistance rates to gentamicin, colistin and tigecycline were 41%, 23% and 16%, respectively. VIM-producing K. pneumoniae were isolated in 2005 and since 2008 have been endemic. KPC-producing K. pneumoniae (KPC-Kp) isolates were introduced in 2008 and until now represent the predominant carbapenemase-producing K. pneumoniae in our institution. PFGE of 97 KPC-Kp strains identified three types: A, 84 (87%); B, 11 (11%); and E, two (2%). Eleven co-producing KPC and VIM K. pneumoniae isolates belonged to PFGE B. The four NDM-positives were classified to type F. The number of K. pneumoniae bacteraemias increased during the study period, which may be solely attributed to the increase of carbapenemase-producing isolates. The threat of carbapenemase-producing K. pneumoniae emphasizes the urgent need for implementation of infection control measures and budgetary allocations to infection control.

  1. [Infectious diseases caused by carbapenemase-producing Enterobacteriaceae--a particular challenge for antibacterial therapy].

    Science.gov (United States)

    Stock, Ingo

    2014-05-01

    Enterobacteriaceae species such as Escherichia coli and Klebsiella pneumoniae are among the most common human pathogens. They are responsible for a wide range of community-acquired and nosocomial diseases. Many of the illnesses caused by these bacteria could be treated with beta-lactams for several decades. The increasing use of carbapenems for the treatment of diseases caused by Enterobacteriaceae expressing extended spectrum beta-lactamases, however, lead to the selection and spread of carbapenemase-producing pathogens. Such bacteria are not only resistant to virtually all beta-lactams, but also to numerous other antibiotics such as quinolones, co-trimoxazole, nitrofurantoin, tetracyclines and most aminoglycosides. During the last years, carbapenemase-producing Enterobacteriaceae have spread into almost all regions of the world. Klebsiella pneumoniae carbapenemases (KPC, belonging to Ambler class A), OXA-48 enzymes and their derivatives (belonging to Ambler class D) as well as some metallo-beta-lactamases (Ambler class B) such as NDM, VIM and IMP are the most important carbapenemases produced by Enterobacteriaceae strains. In Germany, the metallo-carbapenemase GIM-1, which has never been proven in bacteria outside Germany, is also of clinical significance. There is no established antibacterial therapy for these difficult-to-treat diseases. For the treatment of severe diseases caused by carbapenemase-producing bacteria, fosfomycin, gentamicin and tigecycline, polymyxins such as polymyxin B or colistin as well as carbapenems, are frequently applied. Combination antibiotic treatment may be more effective than monotherapy for severe ill patients with serious diseases. The most promising new treatment options arise with the development of avibactam. This non-beta-lactam beta-lactamase inhibitor shows good activity against (nearly) all class A and class C beta-lactamases (including strains expressing class A carbapenemases and/or derepressed AmpC enzymes) as well as

  2. Prevalence and clonality of extended-spectrum beta-lactamases in Asia.

    Science.gov (United States)

    Hawkey, P M

    2008-01-01

    Asia is almost certainly a part of the world in which extended-spectrum beta-lactamases (ESBLs) have emerged de novo, with some early antimicrobial resistance studies showing high levels of the ESBL phenotype, particularly among Klebsiella, and most notably in China, Korea, Japan and India. There is a lack of genotyping studies but work from the late 1990s suggests that SHV-5 and SHV-12 were most common then, with only very rare reports of TEM-related ESBL genes. As in other parts of the world, quite marked differences have since been seen in the pattern of ESBL genes, particularly in relation to the CTX-M family. The early emergence of TOHO CTX-M-2 in Japan contrasted with CTX-M-3 and -14 in China and many other parts of the Far East, suggesting the separate transfer of genes from the genome of Kluyvera spp. to mobile genetic elements in human-associated Enterobacteriaceae. ESBL production rates are now very high compared with Europe. In most countries, there are mixtures of CTX-M types, with VEB appearing significantly in Vietnam and Thailand, and ESBL isolates from India being completely dominated by the presence of bla(CTX-M-15) alone, with no other CTX-M types reported. With the total population of India and China being c. 2.4 billion and with faecal carriage rates of, probably, c. 10%, these countries represent major reservoirs of bla(CTX-M) genes. Increasing international travel and trade will lead to the movement of many of these ESBL genes. The high prevalence of ESBL genes in Asia means that the empirical treatment of serious infections with beta-lactam antibiotics, except carbapenems, is seriously compromised.

  3. Beta-Lactamases among extended-spectrum (beta)-lactamase (ESBL)-resistant Salmonella from poultry, poultry products and human patients in The Netherlands

    NARCIS (Netherlands)

    Hasman, H.; Mevius, D.J.; Veldman, K.T.; Olesen, I.; Aarestrup, F.M.

    2005-01-01

    Objectives: The purpose of this work was to study the genetic determinants responsible for extended-spectrum beta-lactamase (ESBL) resistance of Salmonella isolated from Dutch poultry, poultry meat and hospitalized humans. Methods: Thirty-four ESBL-resistant Salmonella isolates from The Netherlands

  4. Version 2000: the new beta-lactamases of Gram-negative bacteria at the dawn of the new millennium.

    Science.gov (United States)

    Thomson, K S; Smith Moland, E

    2000-08-01

    beta-lactamases of Gram-negative bacteria are evolving dynamically. New developments include the production of enzymes with novel substrate profiles, reduced susceptibility to beta-lactamase inhibitors, and the simultaneous production of multiple types of beta-lactamases. The changes represent evolutionary upgrades which provide modern pathogens with a greater potential to resist beta-lactam antibiotics and cause formidable therapeutic, infection control, and diagnostic challenges. This review is a clinically oriented outline of recent developments in the beta-lactamase production of Gram-negative bacteria.

  5. Structure-Based Design of Potent and Ligand-Efficient Inhibitors of CTX-M Class A [beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, Derek A.; Jaishankar, Priyadarshini; Larson, Wayne; Smith, Emmanuel; Liu, Guoqing; Beyrouthy, Racha; Bonnet, Richard; Renslo, Adam R.; Chen, Yu (USF); (UCSF); (Clermont)

    2012-07-11

    The emergence of CTX-M class A extended-spectrum {beta}-lactamases poses a serious health threat to the public. We have applied structure-based design to improve the potency of a novel noncovalent tetrazole-containing CTX-M inhibitor (K{sub i} = 21 {mu}M) more than 200-fold via structural modifications targeting two binding hot spots, a hydrophobic shelf formed by Pro167 and a polar site anchored by Asp240. Functional groups contacting each binding hot spot independently in initial designs were later combined to produce analogues with submicromolar potencies, including 6-trifluoromethyl-3H-benzoimidazole-4-carboxylic acid [3-(1H-tetrazol-5-yl)-phenyl]-amide, which had a K{sub i} value of 89 nM and reduced the MIC of cefotaxime by 64-fold in CTX-M-9 expressing Escherichia coli. The in vitro potency gains were accompanied by improvements in ligand efficiency (from 0.30 to 0.39) and LipE (from 1.37 to 3.86). These new analogues represent the first nM-affinity noncovalent inhibitors of a class A {beta}-lactamase. Their complex crystal structures provide valuable information about ligand binding for future inhibitor design.

  6. High Prevalence of Extended-Spectrum Beta Lactamases among Salmonella enterica Typhimurium Isolates from Pediatric Patients with Diarrhea in China

    Science.gov (United States)

    Yu, Fangyou; Chen, Qiang; Yu, Xiaojun; Li, Qiaoqiao; Ding, Baixing; Yang, Lehe; Chen, Cong; Qin, Zhiqiang; Parsons, Chris; Zhang, Xueqing; Huang, Jinwei; Luo, Yun; Wang, Liangxing; Pan, Jingye

    2011-01-01

    We investigated the extended-spectrum beta lactamases among 62 Salmonella enterica Typhimurium isolates recovered from children with diarrhea in a Chinese pediatric hospital. A large proportion of S. enterica Typhimurium isolates were resistant to multiple antimicrobial agents, including ampicillin (90.3%), tetracycline (80.6%), trimethoprim/sulfamethoxazole (74.2%), chloramphenicol (66.1%), cefotaxime (27.4%). Forty-nine (79.0%) of S. enterica Typhimurium isolates were positive for blaTEM-1b and resistant to ampicillin. Thirteen S. enterica Typhimurium isolates (21.0%) were positive for blaCTX-M-1-group and blaCTX-M-9-group, and all isolates harboring blaCTX-M genes were positive for ISEcp1. Two main clones (PFGE type A and D) accounted for nearly 70% of S. enterica Typhimurium isolates, and 7 CTX-M-producing isolates belonged to PFGE type D. Collectively, our data reveal multi-drug resistance and a high prevalence of extended spectrum beta lactamases among S. enterica Typhimurium isolates from children in China. In addition, we report the first identification of blaCTX-M-55 within Salmonella spp. Our data also suggest that clonal spread is responsible for the dissemination of S. enterica Typhimurium isolates. PMID:21390297

  7. High prevalence of extended-spectrum beta lactamases among Salmonella enterica Typhimurium isolates from pediatric patients with diarrhea in China.

    Directory of Open Access Journals (Sweden)

    Fangyou Yu

    Full Text Available We investigated the extended-spectrum beta lactamases among 62 Salmonella enterica Typhimurium isolates recovered from children with diarrhea in a Chinese pediatric hospital. A large proportion of S. enterica Typhimurium isolates were resistant to multiple antimicrobial agents, including ampicillin (90.3%, tetracycline (80.6%, trimethoprim/sulfamethoxazole (74.2%, chloramphenicol (66.1%, cefotaxime (27.4%. Forty-nine (79.0% of S. enterica Typhimurium isolates were positive for bla(TEM-1b and resistant to ampicillin. Thirteen S. enterica Typhimurium isolates (21.0% were positive for bla(CTX-M-1-group and bla(CTX-M-9-group, and all isolates harboring bla(CTX-M genes were positive for ISEcp1. Two main clones (PFGE type A and D accounted for nearly 70% of S. enterica Typhimurium isolates, and 7 CTX-M-producing isolates belonged to PFGE type D. Collectively, our data reveal multi-drug resistance and a high prevalence of extended spectrum beta lactamases among S. enterica Typhimurium isolates from children in China. In addition, we report the first identification of bla(CTX-M-55 within Salmonella spp. Our data also suggest that clonal spread is responsible for the dissemination of S. enterica Typhimurium isolates.

  8. Host-Specific Patterns of Genetic Diversity among IncI1-I gamma and IncK Plasmids Encoding CMY-2 beta-Lactamase in Escherichia coli Isolates from Humans, Poultry Meat, Poultry, and Dogs in Denmark

    DEFF Research Database (Denmark)

    Hansen, Katrine Hartung; Bortolaia, Valeria; Nielsen, Christine Ahl

    2016-01-01

    CMY-2 is the most common plasmid-mediated AmpC beta-lactamase in Escherichia coli isolates of human and animal origin. The aim of this study was to elucidate the epidemiology of CMY-2-producing E. coli in Denmark. Strain and plasmid relatedness was studied in 93 CMY-2-producing clinical and comme......CMY-2 is the most common plasmid-mediated AmpC beta-lactamase in Escherichia coli isolates of human and animal origin. The aim of this study was to elucidate the epidemiology of CMY-2-producing E. coli in Denmark. Strain and plasmid relatedness was studied in 93 CMY-2-producing clinical....... These baseline data will be useful to assess the consequences of the increasing human exposure to CMY-2-producing E. coli via animal sources.IMPORTANCECMY-2 is the most common plasmid-mediated AmpC beta-lactamase in Escherichia coli. This beta-lactamase is poorly inhibited by clavulanic acid and confers...

  9. Detecção de metalo-beta-lactamase em Pseudomonas aeruginosa isoladas de pacientes hospitalizados em Goiânia, Estado de Goiás Detection of metallo-beta-lactamase in Pseudomonas aeruginosa isolated from hospitalized patients in Goiânia, State of Goiás

    Directory of Open Access Journals (Sweden)

    Diana Christina Pereira Santos Gonçalves

    2009-08-01

    Full Text Available Pseudomonas aeruginosa é uma bactéria frequentemente isolada no ambiente hospitalar. Este estudo teve como objetivo avaliar o perfil de suscetibilidade de Pseudomonas aeruginosa previamente isoladas de pacientes internados em um hospital de Goiânia (Goiás-Brasil; realizar a triagem fenotípica para a produção de metalo-beta-lactamase e detectar os genes das mesmas pela técnica de "Polimerase Chain Reaction". Foram avaliadas 75 Pseudomonas aeruginosa isoladas no período de janeiro de 2005 a janeiro de 2007. A identificação bioquímica foi realizada pelo sistema API 20E® e o antibiograma pelo método de Kirby-Bauer. Entre os 62 isolados que foram resistentes ao imipenem e à ceftazidima, 35 (56,4% apresentaram produção de metalo-beta-lactamase e em 26 (74,3% destes, foi detectado o gene blaSPM-1. A frequência de Pseudomonas aeruginosa produtoras de metalo-beta-lactamase sugere um maior controle da disseminação de resistência no ambiente hospitalar.Pseudomonas aeruginosa is a bacterium frequently isolated from hospital environments. This study had the aims of evaluating the susceptibility profile of Pseudomonas aeruginosa previously isolated from patients in a hospital in Goiânia (Goiás, Brazil, performing phenotypic screening for metallo-beta-lactamase production and detecting its genes using the polymerase chain reaction technique. Seventy-five 75 Pseudomonas aeruginosa isolates were evaluated between January 2005 and January 2007. Biochemical identification was performed using the API 20E® system and an antibiogram was produced using the Kirby-Bauer method. Among the 62 isolates that were resistant to imipenem and ceftazidime, 35 (56.4% produced metallo-beta-lactamase, while 26 (74.3% showed the blaSPM-1 gene. The frequency of Pseudomonas aeruginosa that produces metallo-beta-lactamase suggests that greater control over the dissemination of resistance in hospital environments is needed.

  10. Structure of GES-1 at Atomic Resolution: Insights Into the Evolution of Carbapenamase Activity in the Class a Extended-Spectrum Beta-Lactamases

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.A.; /SLAC, SSRL; Caccamo, M.; /Notre Dame U.; Kantardjieff, K.A.; /Cal State, Fullerton; Vakulenko, S.; /Notre Dame U.

    2007-10-08

    The structure of the class A extended-spectrum {beta}-lactamase GES-1 from Klebsiella pneumoniae has been determined to 1.1 Angstrom resolution. GES-1 has the characteristic active-site disulfide bond of the carbapenemase family of {beta}-lactamases and has a structure that is very similar to those of other known carbapenemases, including NMC-A, SME-1 and KPC-2. Most residues implicated in the catalytic mechanism of this class of enzyme are present in the GES-1 active site, including Ser70, which forms a covalent bond with the carbonyl C atom of the {beta}-lactam ring of the substrate during the formation of an acyl-enzyme intermediate, Glu166, which is implicated as both the acylation and deacylation base, and Lys73, which is also implicated as the acylation base. A water molecule crucial to catalysis is observed in an identical location as in other class A {beta}-lactamases, interacting with the side chains of Ser70 and Glu166. One important residue, Asn170, also normally a ligand for the hydrolytic water, is missing from the GES-1 active site. This residue is a glycine in GES-1 and the enzyme is unable to hydrolyze imipenem. This points to this residue as being critically important in the hydrolysis of this class of {beta}-lactam substrate. This is further supported by flexible-docking studies of imipenem with in silico-generated Gly170Asn and Gly170Ser mutant GES-1 enzymes designed to mimic the active sites of imipenem-hydrolyzing point mutants GES-2 and GES-5.

  11. An efficient heat-inducible Bacillus subtilis bacteriophage 105 expression and secretion system for the production of the Streptomyces clavuligerus beta-lactamase inhibitory protein (BLIP).

    Science.gov (United States)

    Liu, Hong-Bing; Chui, Ka-Shun; Chan, Chi-Leong; Tsang, Chun-Wai; Leung, Yun-Chung

    2004-03-18

    The Streptomyces clavuligerus beta-lactamase inhibitory protein (BLIP) has been shown to be a potent inhibitor of class A beta-lactamases including the Escherichia coli TEM-1 beta-lactamase (Ki = 0.6 nM). A heat-inducible BLIP expression system was constructed based on a derivative of Bacillus subtilis phage phi105. The recombinant BLIP produced by this system was secreted to the culture medium, purified to homogeneity, and fully active. We have shown that the signal peptide of BLIP functions well in B. subtilis to secrete BLIP out of the cells, which facilitates purification. The absence of a His-tag also avoids the activity and structure of BLIP being altered. An unprecedented high yield of recoverable protein in culture supernatant (3.6mg of >95% pure BLIP/l culture) was achieved by a simple purification protocol. We have developed an efficient production process in which the culture time before heat-induction was 3-4h and the culture supernatant could be collected 5h after induction. This total time of 8-9h is considered to be very short compared to that of the native S. clavuligerus culturing (60-70h). We achieved a very efficient BLIP production rate of 0.8-0.9mg/l/h. Heterologous gene expression was tightly controlled and no production of BLIP was observed before heat-induction, suggesting that cell density can be further increased to improve enzyme yield.

  12. Involvement of a Novel Class C Beta-Lactamase in the Transglutaminase Mediated Cross-Linking Cascade of Streptomyces mobaraensis DSM 40847.

    Directory of Open Access Journals (Sweden)

    Stephan Zindel

    Full Text Available Streptomyces mobaraensis DSM 40847 secretes transglutaminase that cross-links proteins via γ-glutamyl-ε-lysine isopeptide bonds. Characterized substrates are inhibitory proteins acting against various serine, cysteine and metalloproteases. In the present study, the bacterial secretome was examined to uncover additional transglutaminase substrates. Fractional ethanol precipitation of the exported proteins at various times of culture growth, electrophoresis of the precipitated proteins, and sequencing of a 39 kDa protein by mass spectrometry revealed the novel beta-lactamase Sml-1. As indicated by biotinylated probes, Sml-1, produced in E. coli, exhibits glutamine and lysine residues accessible for transglutaminase. The chromogenic cephalosporin analogue, nitrocefin, was hydrolyzed by Sml-1 with low velocity. The obtained Km and kcat values of the recombinant enzyme were 94.3±1.8 μM and 0.39±0.03 s(-1, respectively. Penicillin G and ampicillin proved to be weak inhibitors of nitrocefin hydrolysis (Ki of 0.1 mM and 0.18 mM. Negligible influence of metals on β-lactamase activity ruled out that Sml-1 is a Zn2+-dependent class B beta-lactamase. Rather, sequence motifs such as SITK, YSN, and HDG forming the active core in a hypothetical structure may be typical for class C beta-lactamases. Based on the results, we assume that the novel transglutaminase substrate ensures undisturbed growth of aerial hyphae in Streptomyces mobaraensis by trapping and inactivating hostile beta-lactam antibiotics.

  13. First Description of KPC-2-Producing Escherichia coli and ST15 OXA-48-Positive Klebsiella pneumoniae in Tunisia.

    Science.gov (United States)

    Ben Tanfous, Farah; Alonso, Carla Andrea; Achour, Wafa; Ruiz-Ripa, Laura; Torres, Carmen; Ben Hassen, Assia

    2016-10-18

    The aim of this study was to investigate the molecular features among Klebsiella pneumoniae and Escherichia coli strains showing a resistant/intermediate-resistant phenotype to ertapenem (R/IR-ERT), implicated in colonization/infection in patients of the Hematology and Graft Units of the National Bone Marrow Transplant Center of Tunisia (3-year period, 2011-2014). The major carbapenemase, extended-spectrum beta-lactamase, and plasmidic AmpC beta-lactamase genes were analyzed and characterized by PCR and sequencing. Genetic relatedness was determined by pulsed-field gel electrophoresis (PFGE) using XbaI and multilocus sequencing typing. The blaOXA-48 and blaKPC carbapenemase genes were detected among R/IR-ERT isolates. All R/IR-ERT K. pneumoniae strains (n = 19) had blaOXA-48 gene, and 14/19 strains also harbored the blaCTX-M-15 gene. Eight different PFGE patterns were detected among these K. pneumoniae isolates, and they showed eight different sequences types, ST11 and ST15 being the most prevalent ones. Two out of three R/IR-ERT E. coli isolates carried blaOXA-48 and one coproduced the blaCTX-M-15 gene. One E. coli strain, ascribed to the new sequence type ST5700, harbored the blaKPC-2 gene. E. coli isolates were not clonally related and belonged to different sequence types (ST5700, ST227, and ST58). To our knowledge, this is the first report in Tunisia of either KPC-2 carbapenemase in E. coli or OXA-48 carbapenemase in K. pneumoniae of lineage ST15.

  14. Assessment of AmpC Beta-Lactamase Genes among Clinical Escherichia coli Isolates

    Directory of Open Access Journals (Sweden)

    HedrooshaMolla Agha-Mirzaeie

    2015-11-01

    Full Text Available Background: AmpC bta lactamases play a significant role in creating resistance to third generation cephalosporins worldwide. They mostly express on chromosome of Enterobacteriaceae especially Escherichia coli and cause consequential problem inclinical treatment and lead to failure in diagnosis and phenotypic test recommended byClinical and Laboratory Standards Institute.Methods:Totally 200 E. coli isolates from different hospitals of Tehran were collected. The isolates were screened by disk diffusion method according to the CLSI guidelines. The profiles and prevalence surveys of AmpC (Dha, CITM, Mox and FOX-type β-lactamase genes in clinical isolates of E. coli by phenotypic and molecular methods.  Results:Out of 200 Ecoli isolated, 115 (89.8% and 13 (10.2% isolates were identified as ESBL- and AmpC- beta-lactamase producers, respectively. Among mpC producers, 13 (100% and 5 (38.5% isolates was reported by PCR assay as bla-CITM and Dha respectively. Mox and FOX genes were not detected in any sample.Conclusions:Our results highlight the importance of using molecular detection methods to identify β-lactamase-producer that have resistance to antibiotics. 

  15. Automatic phylogenetic classification of bacterial beta-lactamase sequences including structural and antibiotic substrate preference information.

    Science.gov (United States)

    Ma, Jianmin; Eisenhaber, Frank; Maurer-Stroh, Sebastian

    2013-12-01

    Beta lactams comprise the largest and still most effective group of antibiotics, but bacteria can gain resistance through different beta lactamases that can degrade these antibiotics. We developed a user friendly tree building web server that allows users to assign beta lactamase sequences to their respective molecular classes and subclasses. Further clinically relevant information includes if the gene is typically chromosomal or transferable through plasmids as well as listing the antibiotics which the most closely related reference sequences are known to target and cause resistance against. This web server can automatically build three phylogenetic trees: the first tree with closely related sequences from a Tachyon search against the NCBI nr database, the second tree with curated reference beta lactamase sequences, and the third tree built specifically from substrate binding pocket residues of the curated reference beta lactamase sequences. We show that the latter is better suited to recover antibiotic substrate assignments through nearest neighbor annotation transfer. The users can also choose to build a structural model for the query sequence and view the binding pocket residues of their query relative to other beta lactamases in the sequence alignment as well as in the 3D structure relative to bound antibiotics. This web server is freely available at http://blac.bii.a-star.edu.sg/.

  16. Recognition and Resistance in TEM [superscript beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun; Minasov, George; Blazquez, Jesus; Caselli, Emilia; Prati, Fabio; Shoichet, Brian K. (Degli); (UCSF)

    2010-03-08

    Developing antimicrobials that are less likely to engender resistance has become an important design criterion as more and more drugs fall victim to resistance mutations. One hypothesis is that the more closely an inhibitor resembles a substrate, the more difficult it will be to develop resistant mutations that can at once disfavor the inhibitor and still recognize the substrate. To investigate this hypothesis, 10 transition-state analogues, of greater or lesser similarity to substrates, were tested for inhibition of TEM-1 beta-lactamase, the most widespread resistance enzyme to penicillin antibiotics. The inhibitors were also tested against four characteristic mutant enzymes: TEM-30, TEM-32, TEM-52, and TEM-64. The inhibitor most similar to the substrate, compound 10, was the most potent inhibitor of the WT enzyme, with a K(i) value of 64 nM. Conversely, compound 10 was the most susceptible to the TEM-30 (R244S) mutant, for which inhibition dropped by over 100-fold. The other inhibitors were relatively impervious to the TEM-30 mutant enzyme. To understand recognition and resistance to these transition-state analogues, the structures of four of these inhibitors in complex with TEM-1 were determined by X-ray crystallography. These structures suggest a structural basis for distinguishing inhibitors that mimic the acylation transition state and those that mimic the deacylation transition state; they also suggest how TEM-30 reduces the affinity of compound 10. In cell culture, this inhibitor reversed the resistance of bacteria to ampicillin, reducing minimum inhibitory concentrations of this penicillin by between 4- and 64-fold, depending on the strain of bacteria. Notwithstanding this activity, the resistance of TEM-30, which is already extant in the clinic, suggests that there can be resistance liabilities with substrate-based design.

  17. Diversity of Capsular Polysaccharide Gene Clusters in Kpc-Producing Klebsiella pneumoniae Clinical Isolates of Sequence Type 258 Involved in the Italian Epidemic

    Science.gov (United States)

    D’Andrea, Marco Maria; Amisano, Francesco; Giani, Tommaso; Conte, Viola; Ciacci, Nagaia; Ambretti, Simone; Santoriello, Luisa; Rossolini, Gian Maria

    2014-01-01

    Strains of Klebsiella pneumoniae producing KPC-type beta-lactamases (KPC-Kp) are broadly disseminating worldwide and constitute a major healthcare threat given their extensively drug resistant phenotypes and ability to rapidly disseminate in healthcare settings. In this work we report on the characterization of two different capsular polysaccharide (CPS) gene clusters, named cpsBO-4 and cps207-2, from two KPC-Kp clinical strains from Italy belonging in sequence type (ST) 258, which is one of the most successful ST of KPC-Kp spreading worldwide. While cpsBO-4 was different from known 78 K-types according to the recently proposed typing schemes based on the wzi or wzc gene sequences, cps207-2 was classified as K41 by one of these methods. Bioinformatic analysis revealed that they were represented in the genomic sequences of KPC-Kp from strains of ST258 from different countries, and cpsBO-4 was also detected in a KPC-Kp strain of ST442 from Brazil. Investigation of a collection of 46 ST258 and ST512 (a single locus variant of ST258) clinical strains representative of the recent Italian epidemic of KPC-Kp by means of a multiplex PCR typing approach revealed that cpsBO-4 was the most prevalent type, being detected both in ST258 and ST512 strains with a countrywide distribution, while cps207-2 was only detected in ST258 strains with a more restricted distribution. PMID:24823690

  18. Diversity of capsular polysaccharide gene clusters in Kpc-producing Klebsiella pneumoniae clinical isolates of sequence type 258 involved in the Italian epidemic.

    Directory of Open Access Journals (Sweden)

    Marco Maria D'Andrea

    Full Text Available Strains of Klebsiella pneumoniae producing KPC-type beta-lactamases (KPC-Kp are broadly disseminating worldwide and constitute a major healthcare threat given their extensively drug resistant phenotypes and ability to rapidly disseminate in healthcare settings. In this work we report on the characterization of two different capsular polysaccharide (CPS gene clusters, named cpsBO-4 and cps207-2, from two KPC-Kp clinical strains from Italy belonging in sequence type (ST 258, which is one of the most successful ST of KPC-Kp spreading worldwide. While cpsBO-4 was different from known 78 K-types according to the recently proposed typing schemes based on the wzi or wzc gene sequences, cps207-2 was classified as K41 by one of these methods. Bioinformatic analysis revealed that they were represented in the genomic sequences of KPC-Kp from strains of ST258 from different countries, and cpsBO-4 was also detected in a KPC-Kp strain of ST442 from Brazil. Investigation of a collection of 46 ST258 and ST512 (a single locus variant of ST258 clinical strains representative of the recent Italian epidemic of KPC-Kp by means of a multiplex PCR typing approach revealed that cpsBO-4 was the most prevalent type, being detected both in ST258 and ST512 strains with a countrywide distribution, while cps207-2 was only detected in ST258 strains with a more restricted distribution.

  19. Diversity of capsular polysaccharide gene clusters in Kpc-producing Klebsiella pneumoniae clinical isolates of sequence type 258 involved in the Italian epidemic.

    Science.gov (United States)

    D'Andrea, Marco Maria; Amisano, Francesco; Giani, Tommaso; Conte, Viola; Ciacci, Nagaia; Ambretti, Simone; Santoriello, Luisa; Rossolini, Gian Maria

    2014-01-01

    Strains of Klebsiella pneumoniae producing KPC-type beta-lactamases (KPC-Kp) are broadly disseminating worldwide and constitute a major healthcare threat given their extensively drug resistant phenotypes and ability to rapidly disseminate in healthcare settings. In this work we report on the characterization of two different capsular polysaccharide (CPS) gene clusters, named cpsBO-4 and cps207-2, from two KPC-Kp clinical strains from Italy belonging in sequence type (ST) 258, which is one of the most successful ST of KPC-Kp spreading worldwide. While cpsBO-4 was different from known 78 K-types according to the recently proposed typing schemes based on the wzi or wzc gene sequences, cps207-2 was classified as K41 by one of these methods. Bioinformatic analysis revealed that they were represented in the genomic sequences of KPC-Kp from strains of ST258 from different countries, and cpsBO-4 was also detected in a KPC-Kp strain of ST442 from Brazil. Investigation of a collection of 46 ST258 and ST512 (a single locus variant of ST258) clinical strains representative of the recent Italian epidemic of KPC-Kp by means of a multiplex PCR typing approach revealed that cpsBO-4 was the most prevalent type, being detected both in ST258 and ST512 strains with a countrywide distribution, while cps207-2 was only detected in ST258 strains with a more restricted distribution.

  20. Concomitant detection of biofilm and metallo-beta-lactamases production in gram-negative bacilli

    Directory of Open Access Journals (Sweden)

    Monil Singhai

    2013-01-01

    Full Text Available Carbapenems are mainstay of treating serious multidrug resistant gram-negative biofilm-based infections. However, recent emergence of metallo-beta-lactamases (MbL producing gram-negative bacilli in different parts of world may be related to gain of virulence factors associated with biofilm production. Objectives: To explore the association of MbL and biofilm production in various gram-negative bacilli. Materials and Methods: In this study, 110 non-repetitive ceftazidime resistant gram-negative bacilli were evaluated for biofilm and MβL production. Biofilm forming ability of isolates obtained from various specimens was tested by the tube method. Disks of ceftazidime (30 μg and ceftazidime with ethylenediaminetetraacetic acid (30 μg + 750 μg, prepared in house for MβL detection were used. Chi-square test was used to study the association between biofilm and MβL production. P value <0.05 was considered significant. Results: 88 (80% bacilli had shown biofilm producing ability. The association of biofilm and MβL was significant in cases of non-fermenters as compared to enterobacteriaceae members. Conclusion: The particular combination of virulence factors (biofilm and MβL in bacteria may be a species specific effect which needs to be investigated at molecular level in detail. This may help in designing newer therapies based on interference with biofilm formation and thus countering clinical episodes of antibiotic resistance.

  1. Evaluation of different methods for detection of metallo-beta-lactamases in Pseudomonas aeruginosa clinical isolates.

    Science.gov (United States)

    Bogiel, Tomasz; Deptuła, Aleksander; Gospodarek, Eugenia

    2010-01-01

    Metallo-beta-lactamases (MBLs) produced by Pseudomnonas aeruginosa are a serious threat due to their ability to be transmitted between the same as well as different bacterial species. Different methods are applied in the clinical laboratory to detect MBLs. The aim of this study was to compare 4 phenotypic methods and a PCR assay for their ability to detect MBLs in clinical isolates of carbapenem-resistant P. aeruginosa strains. The study embraced a total of 70 carbapenem-resistant P. aeruginosa strains isolated in The Department of Microbiology of Dr. A. Jurasz University Hospital in Bydgoszcz. The highest percentage (42.9%) of the strains were isolated from Intensive Care Unit patients, mainly from urine samples (31.4%). Methods used in this study were: double-disc synergy tests in two combinations: using ceftazidime with 2-mercaptopropionic acid and imipenem with EDTA, differences in inhibition zone diameters between discs with imipenem/EDTA and imipenem, Etest MBL (AB Biodisk) and molecular amplification of bla(IMP) and bla(VIM) genes responsible for producing MBLs, using PCR assay. The lowest percentage (1.4%) of positive results in detection of MBLs was obtained using PCR assay, the highest (72.9%) by double-disc synergy tests with imipenem and EDTA, but the specificity of this method may be low.

  2. Using steric hindrance to design new inhibitors of class C beta-lactamases

    Energy Technology Data Exchange (ETDEWEB)

    Trehan, Indi; Morandi, F.; Blaszczak, L.C.; Shoichet, Brian K. (NWU)

    2010-03-08

    {beta}-lactamases confer resistance to {beta}-lactam antibiotics such as penicillins and cephalosporins. However, {beta}-lactams that form an acyl-intermediate with the enzyme but subsequently are hindered from forming a catalytically competent conformation seem to be inhibitors of {beta}-lactamases. This inhibition may be imparted by specific groups on the ubiquitous R1 side chain of {beta}-lactams, such as the 2-amino-4-thiazolyl methoxyimino (ATMO) group common among third-generation cephalosporins. Using steric hindrance of deacylation as a design guide, penicillin and carbacephem substrates were converted into effective {beta}-lactamase inhibitors and antiresistance antibiotics. To investigate the structural bases of inhibition, the crystal structures of the acyl-adducts of the penicillin substrate amoxicillin and the new analogous inhibitor ATMO-penicillin were determined. ATMO-penicillin binds in a catalytically incompetent conformation resembling that adopted by third-generation cephalosporins, demonstrating the transferability of such sterically hindered groups in inhibitor design.

  3. INSILICO MODELING AND DOCKING STUDIES OF NEW DELHI METALLO BETA LACTAMASE-1 (SUPER BUG

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    DR. JAYASREE GANUGAPATI,

    2011-03-01

    Full Text Available New Delhi Metallo Beta Lactamase-1 (NDM-1 is a novel beta -lactamase enzyme that is ubiquitously found in Escherichia coli. This enzyme belongs to a B1 subclass of Metallo Beta Lactamases and is known to induce resistance to standard intravenous antibiotics. The tertiary structure of NDM-1 was predicted using Modeller9v7, based on the structural homology of the x-ray crystallographic structures of VIM-2 & VIM- 4 (Verona imipenemase-2 & -4 proteins from Pseudomonas aeruginosa. Further refinement of the structure was done using the loop modeling. Docking Analysis of NDM-1 with flavonoids was then performed using, GOLD, Auto Dock and Argus Lab. The analysis of the results of all three docking softwares suggested that Quercetin may be a potential inhibitor of NDM-1. Further analysis in the wet labmay provide us more information regarding inhibiting of NDM-1.

  4. Cephalosporin resistance in Pseudomonas aeruginosa, with special reference to the proposed trapping of antibiotics by beta-lactamase.

    Science.gov (United States)

    Livermore, D M; Williams, J D; Davy, K W

    1985-02-01

    Resistance of Pseudomonas aeruginosa strains to newer cephalosporins is often associated with stable derepression of synthesis of the chromosomal beta-lactamase. Similar resistance is developed by enzyme inducible (i.e. normal) strains in response to beta-lactamase inducers. By comparing the responses of otherwise isogenic P. aeruginosa beta-lactamase inducibility mutants to antipseudomonal cephalosporins alone or in combination with potent beta-lactamase inducers we confirmed that resistance to cefotaxime, ceftriaxone, cefoperazone, and ceftazidime and latamoxef was caused by beta-lactamase action. The low-level resistance to carbenicillin and cefsulodin which was exhibited by some fully beta-lactamase derepressed strains was not confirmed to be beta-lactamase determined and may have reflected concurrent target or permeability changes. The mechanism whereby the enzyme protected the cell against cefotaxime and ceftriaxone was also investigated. These agents are reportedly stable to the enzyme and some workers have suggested that resistance entails their being trapped rather than hydrolysed. However, the use of a novel model of cellular beta-lactamase function indicated that a hydrolytic resistance mechanism remained likely.

  5. Ceftazidime/avibactam: a novel cephalosporin/nonbeta-lactam beta-lactamase inhibitor for the treatment of complicated urinary tract infections and complicated intra-abdominal infections

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    Hidalgo JA

    2016-07-01

    Full Text Available Jose A Hidalgo,1,2 Celeste M Vinluan,1–3 Nishaal Antony3 1UTEP/UT Austin Cooperative Pharmacy Program, College of Health Sciences, University of Texas at El Paso, El Paso, 2Department of Pharmacy, College of Pharmacy, The University of Texas at Austin, Austin, 3Department of Internal Medicine, Texas Tech University Health Sciences Center, El Paso, TX, USA Abstract: There has been greater interest in developing additional antimicrobial agents due to the increasing health care costs and resistance resulting from bacterial pathogens to currently available treatment options. Gram-negative organisms including Enterobacteriaceae and Pseudomonas aeruginosa are some of the most concerning threats due to their resistance mechanisms: extended-spectrum beta-lactamase production and Klebsiella pneumoniae carbapenemase enzymes. Ceftazidime is a third-generation broad-spectrum cephalosporin with activity against P. aeruginosa and avibactam is a novel nonbeta-lactam beta-lactamase inhibitor. Avycaz®, the trade name for this new combination antibiotic, restores the activity of ceftazidime against some of the previously resistant pathogens. Avycaz was approved in 2015 for the treatment of complicated urinary tract infections, including pyelonephritis, and complicated intra-abdominal infections with the addition of metronidazole in patients with little to no other treatment options. This review article assesses the clinical trials and data that led to the approval of this antibiotic, in addition to its spectrum of activity and limitations. Keywords: ceftazidime/avibactam, Avycaz, complicated urinary tract infections, complicated intra-abdominal infections

  6. Structural Aspects for Evolution of [beta]-Lactamases from Penicillin-Binding Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Meroueh, Samy O.; Minasov, George; Lee, Wenlin; Shoichet, Brian K.; Mobashery, Shahriar (NWU); (UCSF); (Notre)

    2010-03-08

    Penicillin-binding proteins (PBPs), biosynthetic enzymes of bacterial cell wall assembly, and {beta}-lactamases, resistance enzymes to {beta}-lactam antibiotics, are related to each other from an evolutionary point of view. Massova and Mobashery (Antimicrob. Agents Chemother. 1998, 42, 1-17) have proposed that for {beta}-lactamases to have become effective at their function as antibiotic resistance enzymes, they would have had to undergo structure alterations such that they would not interact with the peptidoglycan, which is the substrate for PBPs. A cephalosporin analogue, 7{beta}-[N-Acetyl-L-alanyl-{gamma}-D-glutamyl-L-lysine]-3-acetoxymethyl-3-cephem-carboxylic acid (compound 6), was conceived and synthesized to test this notion. The X-ray structure of the complex of this cephalosporin bound to the active site of the deacylation-deficient Q120L/Y150E variant of the class C AmpC {beta}-lactamase from Escherichia coli was solved at 1.71 {angstrom} resolution. This complex revealed that the surface for interaction with the strand of peptidoglycan that acylates the active site, which is present in PBPs, is absent in the {beta}-lactamase active site. Furthermore, insertion of a peptide in the {beta}-lactamase active site at a location where the second strand of peptidoglycan in some PBPs binds has effectively abolished the possibility for such interaction with the {beta}-lactamase. A 2.6 ns dynamics simulation was carried out for the complex, which revealed that the peptidoglycan surrogate (i.e., the active-site-bound ligand) undergoes substantial motion and is not stabilized for binding within the active site. These factors taken together disclose the set of structure modifications in the antibiotic resistance enzyme that prevent it from interacting with the peptidoglycan, en route to achieving catalytic proficiency for their intended function.

  7. Energetic, Structural, and Antimicrobial Analyses of [beta]-Lactam Side Chain Recognition by [beta]-Lactamases

    Energy Technology Data Exchange (ETDEWEB)

    Caselli, E.; Powers, R.A.; Blaszczak, L.C.; Wu, C.Y.E.; Prati, F.; Shoichet, B.K. (NWU)

    2010-03-05

    Penicillins and cephalosporins are among the most widely used and successful antibiotics. The emergence of resistance to these {beta}-lactams, most often through bacterial expression of {beta}-lactamases, threatens public health. To understand how {beta}-lactamases recognize their substrates, it would be helpful to know their binding energies. Unfortunately, these have been difficult to measure because {beta}-lactams form covalent adducts with {beta}-lactamases. This has complicated functional analyses and inhibitor design. To investigate the contribution to interaction energy of the key amide (R1) side chain of {beta}-lactam antibiotics, eight acylglycineboronic acids that bear the side chains of characteristic penicillins and cephalosporins, as well as four other analogs, were synthesized. These transition-state analogs form reversible adducts with serine {beta}-lactamases. Therefore, binding energies can be calculated directly from K{sub i} values. The K{sub i} values measured span four orders of magnitude against the Group I {beta}-lactamase AmpC and three orders of magnitude against the Group II {beta}-lactamase TEM-1. The acylglycineboronic acids have K{sub i} values as low as 20 nM against AmpC and as low as 390 nM against TEM-1. The inhibitors showed little activity against serine proteases, such as chymotrypsin. R1 side chains characteristic of {beta}-lactam inhibitors did not have better affinity for AmpC than did side chains characteristic of {beta}-lactam substrates. Two of the inhibitors reversed the resistance of pathogenic bacteria to {beta}-lactams in cell culture. Structures of two inhibitors in their complexes with AmpC were determined by X-ray crystallography to 1.90 {angstrom} and 1.75 {angstrom} resolution; these structures suggest interactions that are important to the affinity of the inhibitors. Acylglycineboronic acids allow us to begin to dissect interaction energies between {beta}-lactam side chains and {beta}-lactamases. Surprisingly

  8. Inhibition of AmpC beta-lactamase through a destabilizing interaction in the active site

    Energy Technology Data Exchange (ETDEWEB)

    Trehan, I.; Beadle, B.M.; Shoichet, B.K. (NWU)

    2010-03-08

    {beta}-Lactamases hydrolyze {beta}-lactam antibiotics, including penicillins and cephalosporins; these enzymes are the most widespread resistance mechanism to these drugs and pose a growing threat to public health. {beta}-Lactams that contain a bulky 6(7){alpha} substituent, such as imipenem and moxalactam, actually inhibit serine {beta}-lactamases and are widely used for this reason. Although mutant serine {beta}-lactamases have arisen that hydrolyze {beta}-lactamase resistant {beta}-lactams (e.g., ceftazidime) or avoid mechanism-based inhibitors (e.g., clavulanate), mutant serine {beta}-lactamases have not yet arisen in the clinic with imipenemase or moxalactamase activity. Structural and thermodynamic studies suggest that the 6(7){alpha} substituents of these inhibitors form destabilizing contacts within the covalent adduct with the conserved Asn152 in class C {beta}-lactamases (Asn132 in class A {beta}-lactamases). This unfavorable interaction may be crucial to inhibition. To test this destabilization hypothesis, we replaced Asn152 with Ala in the class C {beta}-lactamase AmpC from Escherichia coli and examined the mutant enzyme's thermodynamic stability in complex with imipenem and moxalactam. Consistent with the hypothesis, the Asn152 {yields} Ala substitution relieved 0.44 and 1.10 kcal/mol of strain introduced by imipenem and moxalactam, respectively, relative to the wild-type complexes. However, the kinetic efficiency of AmpC N152A was reduced by 6300-fold relative to that of the wild-type enzyme. To further investigate the inhibitor's interaction with the mutant enzyme, the X-ray crystal structure of moxalactam in complex with N152A was determined to a resolution of 1.83 {angstrom}. Moxalactam in the mutant complex is significantly displaced from its orientation in the wild-type complex; however, moxalactam does not adopt an orientation that would restore competence for hydrolysis. Although Asn152 forces {beta}-lactams with 6(7){alpha

  9. Dissemination and Molecular Epidemiology of KPC-Producing Klebsiella pneumoniae Collected in Puerto Rico Medical Center Hospitals during a 1-Year Period

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    Iraida E. Robledo

    2011-01-01

    Full Text Available During a 2003-2004 PCR-based surveillance study conducted in 6 Puerto Rico Medical Center hospitals, 27/92 multi-beta-lactam-resistant Klebsiella pneumoniae strains were identified as carbapenemase (KPC positive in 4 hospitals. The objectives of this study were to identify the KPC variants, their genetic relatedness, and any other beta-lactamases present. Susceptibility testing, pulsed field gel electrophoresis (PFGE, isoelectric focusing, PCR, and DNA sequencing were performed. KPC variants -2, -3, -4, and -6 were identified. Additional beta-lactamases detected were TEM, DHA, OXA-9 and -30. Antimicrobial susceptibility to carbapenems varied depending on the KPC variant. Five PFGE genetically related groups were identified in 15 isolates and 12 unrelated types. PFGE profiles suggested that both clonal and horizontal transfer are contributing to the dissemination of these isolates among the various hospitals. Comparison of the 2003 and a 2009 surveillance studies showed a significant increase in the KPC-positive K. pneumoniae isolates in the latter.

  10. [Investigation of OXA type beta-lactamases and PFGE patterns in Acinetobacter baumannii strains resistant to carbapenems].

    Science.gov (United States)

    Keyik, Serafettin; Arslan, Uğur; Türk Dağı, Hatice; Seyhan, Tuba; Fındık, Duygu

    2014-10-01

    Acinetobacter baumannii is an important opportunistic and multidrug-resistant pathogen leading to nosocomial infections. Over the last 10 years, a significant and threatening increase in resistance to carbapenems, mainly due to the dissemination of class D beta-lactamases, has been reported in A.baumannii worldwide. The most common types of beta-lactamases causing carbapenem resistance in A.baumannii are the OXA-23, OXA-24, OXA-40, OXA-58 and OXA-143 type serine beta-lactamases. The aim of this study was to investigate the presence of OXA type beta-lactamases in carbapenem-resistant A.baumannii strains and the clonal relationship between the strains. A total of 105 non-duplicate carbapenem-resistant A.baumannii strains isolated from various clinical samples (68 blood, 18 bronchoalveolar lavage, 13 drainage, 3 urine, 2 cerebrospinal fluid and 1 catheter samples) in the Microbiology Laboratories of Selcuk University, Meram (2009-2012) and Selcuklu (2007-2008) Medical School Hospitals, were included in the study. The isolates were identified by conventional methods and Phoenix 100 BD (BD Diagnostic, USA) and Vitek II (bioMerieux, France) automated systems. Carbapenem susceptibility test was performed by Kirby-Bauer disk diffusion method according to the CLSI standards. bla(OXA 23-like), bla(OXA 24-like), bla(OXA 58-like) and bla(OXA 51-like) genes were amplified by multiplex PCR assay and clonal relatedness was investigated by pulsed-field gel electrophoresis (PFGE) using ApaI enzyme. The bla(OXA 51-like) gene was determined in all carbapenem-resistant A.baumannii isolates, while the bla(OXA 23-like) and bla(OXA 58-like) genes were detected in 46.6% and 53.3% of isolates, respectively. However bla(OXA 24-like) gene was not demonstrated in any isolates. bla(OXA 23-like) gene was determined in both Meram and Selcuklu Medical School hospitals, but bla(OXA 58-like) gene was detected only in Meram Medical School hospital. PFGE analysis of the isolates revealed 32 different

  11. Biochemical Characterization of SFC-1, a class A carbapenem-hydrolyzing beta-lactamase.

    Science.gov (United States)

    Fonseca, Fátima; Sarmento, Ana Cristina; Henriques, Isabel; Samyn, Bart; van Beeumen, Jozef; Domingues, Pedro; Domingues, Maria Rosário; Saavedra, Maria José; Correia, António

    2007-12-01

    The carbapenem-hydrolyzing beta-lactamase SFC-1 from Serratia fonticola UTAD54 was overexpressed in Escherichia coli, purified, and characterized. The enzyme exhibited an apparent molecular mass of 30.5 kDa, determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. SFC-1 hydrolyzes penicillins, cephalosporins, aztreonam, and carbapenems and is inhibited by clavulanic acid, sulbactam, and tazobactam.

  12. New leads of metallo-beta-lactamase inhibitors from structure-based pharmacophore design

    DEFF Research Database (Denmark)

    Olsen, Lars; Jost, Sandra; Adolph, Hans-Werner

    2006-01-01

    , phosphonic and sulfonic acid derivatives, and mercapto-carboxylic acids. All hits were docked into different metallo-beta-lactamases (from classes B1 and B3) using the GOLD docking program. A selection scheme based on the GOLD scores, the Catalyst fit and shape values, and the size of the compounds...

  13. Emergence of OXA-48-Producing Klebsiella pneumoniae in Taiwan.

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    Ling Ma

    Full Text Available The isolation of OXA-48-producing Enterobacteriaceae has increased dramatically in Mediterranean countries in the past 10 years, and has recently emerged in Asia. Between January 2012 and May 2014, a total of 760 carbapenem non-susceptible Klebsiella pneumoniae (CnSKP isolates were collected during a Taiwan national surveillance. Carbapenemases were detected in 210 CnSKP isolates (27.6%, including 162 KPC-2 (n = 1, KPC-3, KPC-17, and NDM-1 (n = 1 each, OXA-48 (n = 4, IMP-8 (n = 18, and VIM-1 (n = 24. The four blaOXA-48 CnSKP isolates were detected in late 2013. Herein we report the emergence OXA-48-producing K. pneumoniae isolates in Taiwan. PFGE analysis revealed that the four isolates belonged to three different pulsotypes. Three isolates harboured blaCTX-M genes and belonged to MLST type ST11. In addition, the plasmids belonged to the incompatibility group, IncA/C. One isolate belonged to ST116 and the plasmid incompatibility group was non-typeable. The sequence upstream of the blaOXA-48 gene in all four isolates was identical to pKPOXA-48N1, a blaOXA-48-carrying plasmid. This is the first report of OXA-48-producing Enterobacteriaceae in Taiwan and the second report to identify blaOXA-48 on an IncA/C plasmid in K. pneumoniae. Given that three isolates belong to the same pandemic clone (ST11 and possess the IncA/C plasmid and similar plasmid digestion profile that indicated the role of clonal spread or plasmid for dissemination of blaOXA-48 gene, the emergence of OXA-48-producing K. pneumoniae in Taiwan is of great concern.

  14. The Survey of Genes Encoding Beta-Lactamases, in Escherichia Coli Resistant to Beta-Lactam and Non-Beta-Lactam Antibiotics

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    Fereshteh Shahcheraghi

    2010-01-01

    Full Text Available Resistance to the new generation of cephalosporins which is mediated by Extended-Spectrum beta-lactamases (ESBLs has been found amongEscherichia coli isolates throughout the world. These resistance genes and their producers, the micro-organisms carrying beta-lactamases, are responsible for serious clinical and therapeutic problems among inpatients and it is necessary to pay more attention to detection of ESBLs producing organisms.Materiasl and MethodsCollectively 260 isolates of E. coli were obtained from 6 hospitals in Tehran (Iran during April-2006 to April-2007. The antibiotic susceptibility patterns of isolates were determined by disk diffusion method. phenotypic confirmatory test (PCT was carried out for screening of ESBLs. Microbroth dilution assay was used to determine the minimum inhibitory concentration (MIC of ceftazidime. Isolates showing MIC≥2 μg/ml were subjected to polymerase chain reaction (PCR targeting blaTEM, blaSHV, blaCTX and blaPER genes. ResultsThe PCT showed that 48.08% of isolates are ESBL producers (125 of 260. The majority of cefotaxime resistant (90.8% and ceftazidime resistant (92.5% isolates were ESBL producers. The obtained results by PCR revealed that 5.77% (n=15 of 260 and 24.23 (n=63 of isolates can produce SHV and TEM type enzymes respectively. blaCTX was detected in 20.38% of isolates (n=53 and none of them could produce blaPER type beta-lactamases. ConclusionThe results of our study showed that the ESBL genes have high prevalence among clinical isolates of E. coli. Such high dissemination of ESBLs is a serious problem for public health and therefore, it's necessary to seek a program for monitoring ESBLs in hospitals.

  15. Structure of the imipenem-hydrolyzing class A beta-lactamase SME-1 from Serratia marcescens.

    Science.gov (United States)

    Sougakoff, Wladimir; L'Hermite, Guillaume; Pernot, Lucile; Naas, Thierry; Guillet, Valérie; Nordmann, Patrice; Jarlier, Vincent; Delettré, Jean

    2002-02-01

    The structure of the beta-lactamase SME-1 from Serratia marcescens, a class A enzyme characterized by its significant activity against imipenem, has been determined to 2.13 A resolution. The overall structure of SME-1 is similar to that of other class A beta-lactamases. In the active-site cavity, most of the residues found in SME-1 are conserved among class A beta-lactamases, except at positions 104, 105 and 237, where a tyrosine, a histidine and a serine are found, respectively, and at position 238, which is occupied by a cysteine forming a disulfide bridge with the other cysteine residue located at position 69. The crucial role played by this disulfide bridge in SME-1 was confirmed by site-directed mutagenesis of Cys69 to Ala, which resulted in a mutant unable to confer resistance to imipenem and all other beta-lactam antibiotics tested. Another striking structural feature found in SME-1 was the short distance separating the side chains of the active serine residue at position 70 and the strictly conserved glutamate at position 166, which is up to 1.4 A shorter in SME-1 compared with other class A beta-lactamases. Consequently, the SME-1 structure cannot accommodate the essential catalytic water molecule found between Ser70 and Glu166 in the other class A beta-lactamases described so far, suggesting that a significant conformational change may be necessary in SME-1 to properly position the hydrolytic water molecule involved in the hydrolysis of the acyl-enzyme intermediate.

  16. Biochemical and molecular characterization of three new variants of AmpC beta-lactamases from Morganella morganii.

    Science.gov (United States)

    Power, Pablo; Galleni, Moreno; Ayala, Juan A; Gutkind, Gabriel

    2006-03-01

    Morganella morganii produces an inducible, chromosomally encoded AmpC beta-lactamase. We describe in this study three new variants of AmpC within this species with apparent pIs of 6.6 (M19 from M. morganii strain PP19), 7.4 (M29 from M. morganii strain PP29), and 7.8 (M37 from M. morganii strain PP37). After gene sequencing, deduced amino acid sequences displayed one to six substitutions when compared to the available Morganella AmpC sequences. An AmpR-encoding gene was also found upstream of ampC, including the LysR regulators' helix-turn-helix DNA-binding domain and the putative T-N11-A-protected region in the ampR-ampC intercistronic sequence. All three AmpC variants were purified from in vitro-generated derepressed mutants and showed overall similar kinetic parameters. None of the observed amino acid changes, occurring at the surface of the protein, appear to have a major influence in their catalytic properties. Morganella AmpCs exhibit the highest catalytic efficiencies (k(cat)/K(m)) on classical penicillins, cefoxitin, narrow-spectrum cephalosporins, and cefotaxime. Cefotaxime was more effectively hydrolyzed than other oxyimino-cephalosporins, whereas cefepime was 3 log-fold less efficiently hydrolyzed than other cephalosporins such as cephalothin. Several differences with other AmpC beta-lactamases were found. Ampicillin was more efficiently hydrolyzed than benzylpenicillin. High k(cat)/K(m) values were observed for oxacillin and piperacillin, which are usually poor substrates for AmpC. A fairly efficient hydrolysis of imipenem was detected as well. Aztreonam, carbenicillin, and tazobactam were effective transient inactivators of these variants.

  17. Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase

    Directory of Open Access Journals (Sweden)

    Adriano Martison Ferreira

    Full Text Available Abstract Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28 mm (penicillin resistant and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29 mm, 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%, followed by MIC determination (85.5%, but the specificity of the former was low (40.0%. The nitrocefin test was the least sensitive (28.9%. However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%. The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

  18. Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase.

    Science.gov (United States)

    Ferreira, Adriano Martison; Martins, Katheryne Benini; Silva, Vanessa Rocha da; Mondelli, Alessandro Lia; Cunha, Maria de Lourdes Ribeiro de Souza da

    Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28mm (penicillin resistant) and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29mm), 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%), followed by MIC determination (85.5%), but the specificity of the former was low (40.0%). The nitrocefin test was the least sensitive (28.9%). However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%). The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

  19. Synthesis, spectral and extended spectrum beta-lactamase studies of transition metal tetraaza macrocyclic complexes.

    Science.gov (United States)

    Kumar, Dinesh; Sharma, Nutan; Nair, Manjula

    2017-01-18

    Urinary tract infections commonly occur in humans due to microbial pathogens invading the urinary tract, which can bring about a range of clinical symptoms and potentially fatal sequelae. The present study is aimed at addressing the development of a new antimicrobial agent against extended spectrum beta lactamase (ESBL) producing E. coli bacteria. We have synthesised some biologically potent (NNNN) donor macrocycles (L 1  = dibenzo[f,n]dipyrido[3,4-b:4',3'-j][1,4,9,12]tetraazacyclohexadecine-6,11,18,23(5H,12H, 7H, 24H)-tetraone, and L 2  = 6,12,19,25-tetraoxo-4,6,11,12,16,18,23,24-octahydrotetrabenzo [b,g,k,p][1,5,10,14]tetra azacyclooctadecine-2,13-dicarboxylic acid) and their Ti and Zr metal complexes in alcoholic media using microwave protocol. Macrocyclic ligands were synthesised by incorporating of 3,5-diaminobenzoic acid, phthalic acid and 3,4-diaminopyridine in 1:1:1 molar ratio. The macrocyclic ligands and their metal complexes have been characterised by elemental analysis, conductance measurement, magnetic measurement and their structure configurations have been determined by various spectroscopic (FTIR, (1)H/(13)C NMR, UV-Vis, LC-MS mass, XRD and TGA) techniques. [ZrL2Cl2]Cl2 metal complex shows excellent antibacterial activity against ESBLs. A zone of inhibition and minimum inhibitory concentration was determined by McFarland and the dilution method, respectively. The spectral studies confirm the binding sites of the nitrogen atom of the macrocycles. An octahedral geometry has been assigned to the metal complexes based on the findings.

  20. Myxococcus xanthus, a gram-negative bacterium, contains a transmembrane protein serine/threonine kinase that blocks the secretion of beta-lactamase by phosphorylation.

    Science.gov (United States)

    Udo, H; Munoz-Dorado, J; Inouye, M; Inouye, S

    1995-04-15

    A gene, pkn2, encoding a Myxococcus xanthus protein with significant similarities to eukaryotic protein serine/threonine kinases, was cloned using the polymerase chain reaction. The open reading frame for the protein, beginning with a GUG initiation codon, consists of 830 amino acids. The amino-terminal 279 residues show 37% identity to catalytic domain of Pkn1, another protein serine/threonine kinase expressed during the development at the onset of sporulation. The catalytic domain of Pkn2 contains 27% and 25% identity to rat Ca2+/calmodulin-dependent protein kinase and Bos taurus rhodopsin kinase, respectively. In the middle of the carboxy-terminal regulatory domain, there is a typical transmembrane domain consisting of 18 hydrophobic residues. The gene product, Pkn2, produced in Escherichia coli under a T7 promoter was phosphorylated at both serine and threonine residues. TEM-beta-lactamase produced in E. coli was found to serve as an effective substrate for Pkn2, phosphorylated only at threonine residues, shifting its apparent molecular mass from 29 to 44 kD. The phosphorylated beta-lactamase was unable to be secreted into the periplasmic space and localized in the cytoplasmic and membrane fractions. Analysis of phoA fusions with pkn2 demonstrated that Pkn2 is a transmembrane protein with the kinase domain in the cytoplasm and the 207-residue carboxy-terminal domain outside the cytoplasmic membrane. Disruption of pkn2 showed no effect on vegetative growth but reduced the yield of myxospores by 30%-50%. On the basis of the present results, we propose that Pkn2 is a transmembrane protein serine/threonine kinase that regulates the activity of endogenous beta-lactamase or related enzymes in response to an external signal yet to be identified.

  1. Evaluation of a DNA microarray, the check-points ESBL/KPC array, for rapid detection of TEM, SHV, and CTX-M extended-spectrum beta-lactamases and KPC carbapenemases.

    Science.gov (United States)

    Naas, T; Cuzon, G; Truong, H; Bernabeu, S; Nordmann, P

    2010-08-01

    Extended-spectrum beta-lactamases (ESBLs) and Klebsiella pneumoniae carbapenemases (KPC carbepenemases) have rapidly emerged worldwide and require rapid identification. The Check-Points ESBL/KPC array, a new commercial system based on genetic profiling for the direct identification of ESBL producers (SHV, TEM, and CTX-M) and of KPC producers, was evaluated. Well-characterized Gram-negative rods (Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii) expressing various ss-lactamases (KPC-2, SHV, TEM, and CTX-M types) were used as well as wild-type reference strains and isolates harboring ss-lactamase genes not detected by the assay. In addition, phenotypically confirmed ESBL producers isolated in clinical samples over a 3-month period at the Bicetre hospital were analyzed using the Check-Points ESBL/KPC array and by standard PCR. The Check-Points ESBL/KPC array allowed fast detection of all TEM, SHV, and CTX-M ESBL genes and of the KPC-2 gene. The assay allowed easy differentiation between non-ESBL TEM and SHV and their ESBL derivatives. None of the other tested ss-lactamase genes were detected, underlining its high specificity. The technique is suited for Enterobacteriaceae but also for P. aeruginosa and A. baumannii. However, for nonfermenters, especially P. aeruginosa, a 1:10 dilution of the total DNA was necessary to detect KPC-2 and SHV-2a genes reliably. The Check-Points ESBL/KPC array is a powerful high-throughput tool for rapid identification of ESBLs and KPC producers in cultures. It provided definitive results within the same working day, allowing rapid implementation of isolation measures and appropriate antibiotic treatment. It showed an interesting potential for routine laboratory testing.

  2. First identification of class A carbapenemase-producing Klebsiella pneumoniae in the Republic of Ireland.

    LENUS (Irish Health Repository)

    Roche, C

    2009-04-02

    The Klebsiella pneumoniae carbapenemase (KPC) was detected in a carbapenem-resistant respiratory isolate of Klebsiella pneumoniae in an Irish hospital. This is the first report of a KPC-producing isolate in the Republic of Ireland. The isolate was resistant to all beta-lactams. Furthermore, it had reduced susceptibility to three other classes of non-beta-lactam antibiotics. The isolate was not associated with travel abroad. Detection of KPC-producing bacteria has important infection control and public health implications.

  3. Beta-lactamases among Extended spectrum Beta-lactamase resistant (ESBL) Salmonella from poultry, poultry products and human patients in The Netherlands

    DEFF Research Database (Denmark)

    Hasman, Henrik; Mevius, D.; Veldman, K.

    2006-01-01

    Objectives: The purpose of this work was to study the genetic determinants responsible for extended-spectrum beta-lactamase (ESBL) resistance of Salmonella isolated from Dutch poultry, poultry meat and hospitalized humans. Methods: Thirty-four ESBL-resistant Salmonella isolates from The Netherlands...... were tested towards 21 antimicrobial agents. PCR and sequencing were used to determine the underlying genetic determinants responsible for the ESBL phenotypes. The transferability of the ESBL phenotypes was tested by conjugation to a susceptible Salmonella enterica serovar Dublin and plasmid...

  4. beta-Lactamases among extended-spectrum beta-lactamase (ESBL)-resistant Salmonella from poultry, poultry products and human patients in The Netherlands

    DEFF Research Database (Denmark)

    Hasman, Henrik; Mevius, D.; Veldman, K.

    2005-01-01

    Objectives: The purpose of this work was to study the genetic determinants responsible for extended-spectrum beta-lactamase (ESBL) resistance of Salmonella isolated from Dutch poultry, poultry meat and hospitalized humans. Methods: Thirty-four ESBL-resistant Salmonella isolates from The Netherlands...... were tested towards 21 antimicrobial agents. PCR and sequencing were used to determine the underlying genetic determinants responsible for the ESBL phenotypes. The transferability of the ESBL phenotypes was tested by conjugation to a susceptible Salmonella enterica serovar Dublin and plasmid...

  5. High beta-Lactamase Levels Change the Pharmacodynamics of beta-Lactam Antibiotics in Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Wang, Hengzhuang; Ciofu, Oana; Yang, Liang

    2013-01-01

    Resistance to beta-lactam antibiotics is a frequent problem in Pseudomonas aeruginosa lung infection of cystic fibrosis (CF) patients. This resistance is mainly due to the hyperproduction of chromosomally encoded beta-lactamase and biofilm formation. The purpose of this study was to investigate...... the role of beta-lactamase in the pharmacokinetics (PK) and pharmacodynamics (PD) of ceftazidime and imipenem on P. aeruginosa biofilms. P. aeruginosa PAO1 and its corresponding beta-lactamase-overproducing mutant, PA Delta DDh2Dh3, were used in this study. Biofilms of these two strains in flow chambers...... activity of ceftazidime was observed for beta-lactamase-overproducing biofilms of P. aeruginosa in all three models. Ceftazidime showed time-dependent killing on planktonic PAO1 and PA Delta DDh2Dh3. This difference is probably due to the special distribution and accumulation in the biofilm matrix of beta...

  6. SME-3, a novel member of the Serratia marcescens SME family of carbapenem-hydrolyzing beta-lactamases.

    Science.gov (United States)

    Queenan, Anne Marie; Shang, Wenchi; Schreckenberger, Paul; Lolans, Karen; Bush, Karen; Quinn, John

    2006-10-01

    Imipenem-resistant Serratia marcescens isolates were cultured from a lung transplant patient given multiple antibiotics over several months. The strains expressed SME-3, a beta-lactamase of the rare SME carbapenem-hydrolyzing family. SME-3 differed from SME-1 by a single amino acid substitution of tyrosine for histidine at position 105, but the two beta-lactamases displayed similar hydrolytic profiles.

  7. An outbreak of colistin-resistant Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae in the Netherlands (July to December 2013), with inter-institutional spread

    NARCIS (Netherlands)

    Weterings, V; Zhou, K; Rossen, J W; van Stenis, D; Thewessen, E; Kluytmans, J; Veenemans, J

    2015-01-01

    We describe an outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-KP) ST258 that occurred in two institutions (a hospital and a nursing home) in the Netherlands between July and December 2013. In total, six patients were found to be positive for KPC-KP. All is

  8. Horizontol dissemination of TEM- and SHV-typr beta-lactamase genes-carrying resistance plasmids amongst clonical isolates of Enterobacteriaceae Disseminação horizontal de plasmídios de resistência contendo genes de beta-lactamase dos tipos TEM e SHV entre isolados clínicos de Enterobacteriaceae

    Directory of Open Access Journals (Sweden)

    Osman Birol Ozgumus

    2008-12-01

    Full Text Available The extended-spectrum β-lactamase (ESBL-producing bacteria have been isolated at increasing frequency worldwide. Expression of ESBL is often associated with multidrug resistance and dissemination by resistance plasmids. During a two-month period in 2000, 133 clinical isolates of enterobacterial strains were randomly collected from outpatients and inpatients at a university hospital in Turkey. The ESBL producing strains were determined by double-disk synergy (DDS testing. Twenty ESBL producing strains (15% including Escherichia coli (n = 9, Klebsiella pneumoniae (n = 7, Klebsiella oxytoca (n = 2 and Enterobacter aerogenes (n = 2 were detected and further analyzed for their resistance transfer features, plasmid profile and nature of the resistance genes. Plasmid transfer assays were performed using broth mating techniques. TEM- and SHV- genes were analyzed by polymerase chain reaction (PCR and hybridization using specific probes. EcoRI restriction enzyme analyses of R plasmids were used in the detection of epidemic plasmids. Fourteen plasmid profiles (A, B1, B2, C1, and C2 to L were obtained with EcoRI restriction enzyme analysis. Most of these plasmids were detected to carry both TEM- and SHV-derived genes by PCR, and confirmed by localizing each gene by hybridization assay. Epidemiological evidence indicated that there was an apparent horizontal dissemination of conjugative R plasmids among multidrug-resistant enterobacterial genera and species in this hospitalO isolamento de bactérias produtoras de beta-lactamases de espectro expandido (ESBL está aumentando no mundo todo. Freqüentemente, a expressão de ESBL está associada com resistência a múltiplas drogas e disseminação por plasmídios de resistência. Durante um período de dois meses em 2000, 133 isolados clínicos de cepas de enterobactérias foram obtidos aleatoriamente de pacientes internos e externos de um hospital universitário na Turquia. As cepas produtoras de ESBL foram

  9. Lactam hydrolysis catalyzed by mononuclear metallo-beta-lactamases: A density functional study

    DEFF Research Database (Denmark)

    Hemmingsen, Lars Bo Stegeager; Olsen, L.; Antony, J.

    2003-01-01

    . For most studied systems, the tetrahedral structure is a stable intermediate. Moreover, the C-N bond in the lactam ring is intact in this intermediate, as well as in the following transition state-its cleavage is induced by proton transfer to the nitrogen atom in the lactam ring. However, for the model...... with Asp as a proton shuttle, attack of the zinc-bond hydroxide ion seems to be concerted with the proton transfer. We have also studied the effect of replacing one of the histidine ligands by an asparagine or glutamine residue, giving a zinc site representative of other subclasses of metallo......Two central steps in the hydrolysis of lactam antibiotics catalyzed by mononuclear metallo-beta-lactamases, formation of the tetrahedral intermediate and its breakdown by proton transfer, are studied for model systems using the density functional B3LYP method. Metallo-beta-lactamases have two metal...

  10. Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions.

    Science.gov (United States)

    Wolters, Manuel; Zobiak, Bernd; Nauth, Theresa; Aepfelbacher, Martin

    2015-10-13

    Many gram-negative bacteria including pathogenic Yersinia spp. employ type III secretion systems to translocate effector proteins into eukaryotic target cells. Inside the host cell the effector proteins manipulate cellular functions to the benefit of the bacteria. To better understand the control of type III secretion during host cell interaction, sensitive and accurate assays to measure translocation are required. We here describe the application of an assay based on the fusion of a Yersinia enterocolitica effector protein fragment (Yersinia outer protein; YopE) with TEM-1 beta-lactamase for quantitative analysis of translocation. The assay relies on cleavage of a cell permeant FRET dye (CCF4/AM) by translocated beta-lactamase fusion. After cleavage of the cephalosporin core of CCF4 by the beta-lactamase, FRET from coumarin to fluorescein is disrupted and excitation of the coumarin moiety leads to blue fluorescence emission. Different applications of this method have been described in the literature highlighting its versatility. The method allows for analysis of translocation in vitro and also in in vivo, e.g., in a mouse model. Detection of the fluorescence signals can be performed using plate readers, FACS analysis or fluorescence microscopy. In the setup described here, in vitro translocation of effector fusions into HeLa cells by different Yersinia mutants is monitored by laser scanning microscopy. Recording intracellular conversion of the FRET reporter by the beta-lactamase effector fusion in real-time provides robust quantitative results. We here show exemplary data, demonstrating increased translocation by a Y. enterocolitica YopE mutant compared to the wild type strain.

  11. Surveillance and Detection of Inhibitor-Resistant Beta-Lactamases in Clinical Isolates of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Carl Urban

    2007-06-01

    Full Text Available In recent years, resistance to beta-lactam antibiotics, such as the widely-used cephalosporins and penicillins, has become a major challenge for disease therapy, particularly in common hospital-acquired infections. In the search for the mechanisms behind this increasingly prevalent form of resistance, microbiologists have identified a new type of beta-lactamase enzyme, called inhibitor-resistant TEMs (IRTs, which can withstand the effects of beta-lactamase inhibitor compounds, further reducing the arsenal of drugs available to physicians facing resistant bacteria. In this study, we examined the enzymatic and genetic basis of Escherichia coli isolates demonstrating such resistance to beta-lactam/beta-lactamase inhibitor combinations. Susceptibility trials played a major role in composing the experimental cohort for this project (n=50; each isolate was thoroughly tested to ensure that it was resistant to ampicillin-sulbactam, an inhibitor combination, but susceptible to the third-generation cephalosporin ceftazidime. Subsequently, a number of samples were subjected to assay by pulsed-field gel electrophoresis (n=18 and polymerase chain reaction (n=3 so that their genetic composition and relatedness might be known. In particular, the presence of genes coding for TEM-type beta-lactamases was investigated for each of the 3 isolates sequenced. Even though it was anticipated that the isolates would possess resistance to inhibitor combinations due to an IRT gene, this was not found to be the case. Instead, the mechanism of resistance turned out to be over-expression of a gene coding for a normal TEM enzyme. The results of these experiments have implications for ensuring successful therapy of bacterial infections and for preventing the spread of antimicrobial resistance.

  12. Amino acid residues that contribute to substrate specificity of class A beta-lactamase SME-1.

    Science.gov (United States)

    Majiduddin, Fahd K; Palzkill, Timothy

    2005-08-01

    Carbapenem antibiotics are used as antibiotics of last resort because they possess a broad spectrum of antimicrobial activity and are not easily hydrolyzed by beta-lactamases. Recently, class A enzymes, such as the SME-1, NMC-A, and IMI-1 beta-lactamases, have been identified with the capacity to hydrolyze carbapenem antibiotics. Traditional class A beta-lactamases, such as TEM-1 and SHV-1, are unable to hydrolyze carbapenem antibiotics and exhibit some differences in sequence from those that are able to hydrolyze carbapenem antibiotics. The positions that differ may contribute to the unique substrate specificity of the class A carbapenemase SME-1. Codons in the SME-1 gene representing residues 104, 105, 132, 167, 237, and 241 were randomized by site-directed mutagenesis, and functional mutants were selected for the ability to hydrolyze imipenem, ampicillin, or cefotaxime. Although several positions are important for hydrolysis of beta-lactam antibiotics, no single position was found to uniquely contribute to carbapenem hydrolysis. The results of this study support a model whereby the carbapenemase activity of SME-1 is due to a highly distributed set of interactions that subtly alter the structure of the active-site pocket.

  13. A fitness cost associated with the antibiotic resistance enzyme SME-1 beta-lactamase.

    Science.gov (United States)

    Marciano, David C; Karkouti, Omid Y; Palzkill, Timothy

    2007-08-01

    The bla(TEM-1) beta-lactamase gene has become widespread due to the selective pressure of beta-lactam use and its stable maintenance on transferable DNA elements. In contrast, bla(SME-1) is rarely isolated and is confined to the chromosome of carbapenem-resistant Serratia marcescens strains. Dissemination of bla(SME-1) via transfer to a mobile DNA element could hinder the use of carbapenems. In this study, bla(SME-1) was determined to impart a fitness cost upon Escherichia coli in multiple genetic contexts and assays. Genetic screens and designed SME-1 mutants were utilized to identify the source of this fitness cost. These experiments established that the SME-1 protein was required for the fitness cost but also that the enzyme activity of SME-1 was not associated with the fitness cost. The genetic screens suggested that the SME-1 signal sequence was involved in the fitness cost. Consistent with these findings, exchange of the SME-1 signal sequence for the TEM-1 signal sequence alleviated the fitness cost while replacing the TEM-1 signal sequence with the SME-1 signal sequence imparted a fitness cost to TEM-1 beta-lactamase. Taken together, these results suggest that fitness costs associated with some beta-lactamases may limit their dissemination.

  14. A detailed kinetic study of Mox-1, a plasmid-encoded class C beta-lactamase.

    Science.gov (United States)

    Alba, Jimena; Bauvois, Cedric; Ishii, Yoshikazu; Galleni, Moreno; Masuda, Katsuyoshi; Ishiguro, Masaji; Ito, Masahiko; Frere, Jean-Marie; Yamaguchi, Keizo

    2003-08-29

    Surveys of beta-lactamases in different parts of the world show an important increase in class C beta-lactamases, thus the study of these enzymes is becoming an important issue. We created an overproduction system for Mox-1, a plasmid class C beta-lactamase, by cloning the gene encoding this enzyme, and placing it under the control of a T7 promoter, using vector pET 28a. The enzyme, purified by ion exchange chromatography, was used to obtain the molecular mass (38246), the N-terminal sequence (GEASPVDPLRPVV), and pI (8.9), and to perform a detailed kinetic study. Cephalotin was used as reporter substrate in the case of poor substrates. The kinetic study showed that benzylpenicillin, cephalotin, cefcapene and moxalactam were good substrates for Mox-1 (k(cat)/K(m) values >2.5 x 10(6) M(-1) s(-1)). On the other hand, ceftazidime and cefepime were poor substrates for this enzyme (K(m) values >200 microM). Clavulanic acid had no inhibitory effect on Mox-1 (K(m)=30.2 mM), however aztreonam behaved as an inhibitor of Mox-1 (K(i)=2.85 microM).

  15. First Report of Group CTX-M-9 Extended Spectrum Beta-Lactamases in Escherichia coli Isolates from Pediatric Patients in Mexico

    Science.gov (United States)

    Merida-Vieyra, Jocelin; De Colsa, Agustin; Calderon Castañeda, Yair; Arzate Barbosa, Patricia; Aquino Andrade, Alejandra

    2016-01-01

    The aim of this study was to identify the presence of group CTX-M-9 extended spectrum beta-lactamases (ESBL) in clinical Escherichia coli isolates from pediatric patients. A total of 404 non-repeated positive ESBL E. coli isolates were collected from documented clinical infections in pediatric patients over a 2-year period. The identification and susceptibility profiles were determined using an automated system. Isolates that suggested ESBL production based on their resistance profiles to third and fourth generation cephalosporin and monobactam were selected. ESBL production was phenotypically confirmed using a diffusion method with cefotaxime and ceftazidime discs alone and in combination with clavulanic acid. blaESBL gene identification was performed through PCR amplification and sequencing. Pulsed Field Gel Electrophoresis (PFGE) and Multilocus Sequence Typing (MLST) were performed to establish the clonal relationships of the E. coli isolates. CTX-M-9-type ESBLs were detected in 2.5% of the isolates. The subtypes corresponded to blaCTX-M-14 (n = 4) and blaCTX-M-27 (n = 6). Additionally, coexistence with other beta-lactamases was observed. A clonal relationship was established in three isolates; the rest were classified as non-related. We found seven different sequence type (ST) in CTX-M-9- producing E. coli isolates. ST38 was the most frequent. This study is the first report in Mexico to document the presence of group CTX-M-9 ESBLs in E. coli isolates from pediatric patients. PMID:27992527

  16. Study on the Genotype of Extended-spectrum Beta-lactamases Mediated by Plasmid in Southern China

    Institute of Scientific and Technical Information of China (English)

    陆坚; 唐英春; 文丽霞; 张扣兴; 张天托; 朱家馨; 谈淑卿

    2004-01-01

    To investigate the prevalence and genotype of extended spectrum beta-lactamases (ESBLs) mediated by plasmid in Gram-negative bacteria found in southern China, a total of 1184 clinical isolates of non-repetitive strains of Gram-negative bacteria were collected in 2001 from 5 different cities in southern China. The ESBLs-producing isolates were distinguished by means of the phenotype confimatory test based on the NCCLS criteria and were subjected to plasmid conjugation and electroporation experiments. Those clinical isolates succeeded in plasmid transfers had undergone plasmid conjugation and electro-transformation, plasmid DNA extraction and Pst Ⅰ digest linger-printing analysis, as well as the tmiversal primer PCR amplification of the TEM, SHV, CTX-M, VEB, PER and SFO genes and the DNA sequencing in order to determine the genotypes of ESBLs and their plasmid locations. It was found that the incidence of the ESBLs-producing strains of Gram-negative bacteria was 14.6% (173/1184) with 67 strains of transconjugants and 11 strains of electro-transformants, in which CTX-M-14 type was 33.3% (26/78); CTX-M-3 type was 23.1% (18/78); CTX-M-9 type was 14.1% (11/78); CTX-M-5 type was 6.4% (5/78); CTX-M-13 type was 2.6% (2/78); SHV-5 type was 7.7% (6/78); SHV-12 type was 5.1% (4/78), SHV-2a type was 2.6% (2/78) and unidentified type was 5.1% (4/78). 29.5% of the wild strains also carried broad-spectrum beta-lactamases TEM-1 and SHV-1 types. The above mentioned ESBLs genes were located on transferable plasmids with variable sizes (from 35 to 190 kb). The CTX-M type ESBLs was characterized by high-level of resistance to cefotaxime. It concluded that the CTX-M-type was the most prevalent genotype in clinical isolates of Gram-negative bacteria in southern China, and the SHVtype ranks in the second place. TEM-, VEB-, Toho- and PER-types were not found in these isolates.

  17. Antibiotic combinatorial approach utilized against extended spectrum beta-lactamase (ESBL bacteria isolates from Enugu, South Eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Ruth A. Afunwa

    2014-04-01

    Full Text Available Introduction: Antibiotic options in the treatment of extended spectrum beta-lactamase (ESBL producing bacteria are very limited. The purpose of this study was to analyze several commonly applied antibiotics in quite various novel combinations for use against ESBL-producing bacteria isolates.Methods: Total of 460 samples of urine, throat and anal swab were collected from volunteers and patients from nursery, primary and secondary schools and from other individuals in the community. Hospital and community isolates comprised of 65% and 35% respectively. The identification and characterization of the isolates were done by standard culturing and in vitro antibiotic sensitivity procedures.Results: The antibiotic combination studies showed that the combination of gentamicin with the other antibiotics had predominantly synergistic effects. The percentage synergistic effect for the combinations of gentamicin/pefloxacin was 69%, gentamicin/[Amoxicillin and clavulanic acid] 72%, gentamicin/ceftriaxone 68%, gentamicin/cefuroxime 81.9%, and gentamicin/ciprofloxacin 80.6%, against the community and hospital derived ESBL producing organisms of both Enterobacteriaceae and Pseudomonas species.Conclusion: Good antimicrobial monitoring exercise and corresponding antimicrobial screening activities should work towards a dynamic approach to generate effective treatment options using combination therapy.

  18. Genomic Characterization of Two KPC-Producing Klebsiella Isolates Collected in 1997 in New York City.

    Science.gov (United States)

    Eilertson, Brandon; Chen, Liang; Chavda, Kalyan D; Kreiswirth, Barry N

    2017-04-01

    Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae have now become a global public health threat. However, the origin of this pandemic and the characterization of pre-2003 blaKPC-harboring plasmids remain unknown. Here we used next-generation sequencing to characterize two KPC-2-producing K. pneumoniae and Kmichiganensis isolates collected from a New York City hospital in 1997. Although identified in two different Klebsiella species, the blaKPC-2 gene was harbored by Tn4401b transposons on two highly similar IncN plasmids.

  19. The KPC type beta-lactamases: new enzymes that confer resistance to carbapenems in Gram-negative bacilli.

    Directory of Open Access Journals (Sweden)

    Piotr Wieczorek

    2010-05-01

    Full Text Available Antimicrobial resistance due to the continuous selective pressure from widespread use of antimicrobials in humans, animals and agriculture has been a growing problem for last decades. KPC beta-lactamases hydrolyzed beta-lactams of all classes. Especially, carbapenem antibiotics are hydrolyzed more efficiency than other beta-lactam antibiotics. The KPC enzymes are found most often in Enterobacteriaceae. Recently, these enzymes have been found in isolates of Pseudomonas aeruginosa and Acinetobacter spp. The observations of blaKPC genes isolated from different species in other countries indicate that these genes from common but unknown ancestor may have been mobilized in these areas or that blaKPC-carrying bacteria may have been passively by many vectors. The emergence of carbapenem resistance in Gram-negative bacteria is worrisome because the carbapenem resistance often may be associated with resistance to many beta-lactam and non-beta-lactam antibiotics. Treatment of infections caused by KPC-producing bacteria is extremely difficult because of their multidrug resistance, which results in high mortality rates. Therapeutic options to treat infections caused by multiresistant Gram-negative bacteria producing KPC-carbapenemases could be used polymyxin B or tigecycline.

  20. Evolution of CTX-M-type beta-lactamases in isolates of Escherichia coli infecting hospital and community patients.

    Science.gov (United States)

    Brigante, Gioconda; Luzzaro, Francesco; Perilli, Mariagrazia; Lombardi, Gianluigi; Colì, Alessandra; Rossolini, Gian Maria; Amicosante, Gianfranco; Toniolo, Antonio

    2005-02-01

    Escherichia coli isolates collected at our Institution from 1999 to 2003 (n=20,258) were studied to evaluate the production of CTX-M-type extended-spectrum beta-lactamases (ESBL). Isolates suspected of producing CTX-M enzymes were analyzed by the double-disk synergy test, hybridization with specific probes, PCR and direct DNA sequencing. Overall, 53 ESBL-positive isolates were found to carry CTX-M-type genes (blaCTX-M-1, n=51; blaCTX-M-15, n=2). The isolation of CTX-M-positive strains increased from 1 per year (1999) to 26 per year (2003). The first isolate carrying the blaCTX-M-15 gene appeared in 2003 and was obtained from a patient previously treated with ceftazidime. CTX-M-positive isolates were characterized by multi-drug resistance and were obtained both from inpatients (n=29) and outpatients (n=24). Most patients were over 60-year-old (n=45), had underlying chronic diseases (n=32), and had been hospitalized more than once (n=33). Strains were frequently isolated from the urinary tract, often after recurrent infections. Our study demonstrates that CTX-M-producing isolates are increasing among E. coli strains. Adequate laboratory detection may help in choosing appropriate treatment and in limiting the spread of this resistance trait.

  1. The Deacylation Mechanism of AmpC [beta]-Lactamase at Ultrahigh Resolution

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu; Minasov, George; Roth, Tomer A.; Prati, Fabio; Shoichet, Brian K. (Degli); (NWU); (UCSF)

    2010-03-05

    {beta}-Lactamases confer bacterial resistance to {beta}-lactam antibiotics, such as penicillins. The characteristic class C {beta}-lactamase AmpC catalyzes the reaction with several key residues including Ser64, Tyr150, and Lys67. Here, we describe a 1.07 {angstrom} X-ray crystallographic structure of AmpC {beta}-lactamase in complex with a boronic acid deacylation transition-state analogue. The high quality of the electron density map allows the determination of many proton positions. The proton on the Tyr150 hydroxyl group is clearly visible and is donated to the boronic oxygen mimicking the deacylation water. Meanwhile, Lys67 hydrogen bonds with Ser64O{gamma}, Asn152O{delta}1, and the backbone oxygen of Ala220. This suggests that this residue is positively charged and has relinquished the hydrogen bond with Tyr150 observed in acyl-enzyme complex structures. Together with previous biochemical and NMR studies, these observations indicate that Tyr150 is protonated throughout the reaction coordinate, disfavoring mechanisms that involve a stable tyrosinate as the general base for deacylation. Rather, the hydroxyl of Tyr150 appears to be well positioned to electrostatically stabilize the negative charge buildup in the tetrahedral high-energy intermediate. This structure, in itself, appears consistent with a mechanism involving either Tyr150 acting as a transient catalytic base in conjunction with a neutral Lys67 or the lactam nitrogen as the general base. Whereas mutagenesis studies suggest that Lys67 may be replaced by an arginine, disfavoring the conjugate base mechanism, distinguishing between these two hypotheses may ultimately depend on direct determination of the pKa of Lys67 along the reaction coordinate.

  2. Structural Basis for Imipenim Inhibition of Class C [beta]-Lactamases

    Energy Technology Data Exchange (ETDEWEB)

    Beadle, Beth M.; Shoichet, Brian K. (NWU)

    2010-03-05

    To determine how imipenem inhibits the class C {beta}-lactamase AmpC, the X-ray crystal structure of the acyl-enzyme complex was determined to a resolution of 1.80 {angstrom}. In the complex, the lactam carbonyl oxygen of imipenem has flipped by approximately 180{sup o} compared to its expected position; the electrophilic acyl center is thus displaced from the point of hydrolytic attack. This conformation resembles that of imipenem bound to the class A enzyme TEM-1 but is different from that of moxalactam bound to AmpC.

  3. Expression, purification, crystallization and preliminary X-ray analysis of Aeromonas hydrophilia metallo-[beta]-lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, N.; Toney, J.H.; Fitzgerald, P.M.D. (Merck)

    2010-07-20

    The CphA metallo-{beta}-lactamase from Aeromonas hydrophilia has been expressed, purified and crystallized by the hanging-drop vapor-diffusion method using ammonium sulfate as the precipitant. The crystals exhibit orthorhombic symmetry (P2{sub 1}2{sub 1}2), with unit-cell parameters a = 40.75, b = 42.05, c = 128.88 {angstrom}. There is one monomer in the asymmetric unit and the solvent content is estimated to be 44% by volume. A data set extending to 1.8 {angstrom} has been measured.

  4. Emergence of pan-resistance in KPC-2 carbapenemase-producing Klebsiella pneumoniae in Crete, Greece : a close call

    NARCIS (Netherlands)

    Bathoorn, E.; Tsioutis, C.; Voorham, J. M. da Silva; Scoulica, E. V.; Ioannidou, E.; Zhou, K.; Rossen, J. W.; Gikas, A.; Friedrich, A. W.; Grundmann, H.

    2016-01-01

    Molecular resistance markers for pan-resistant isolates of KPC-producing Klebsiella pneumoniae were identified and showed core-genome MLST to be a promising tool for tracking outbreaks and transmission pathways.KPC-2-producing Klebsiella pneumoniae (KPC-KP) ST258 has been rapidly expanding and is of

  5. Vibrio cholerae MARTX toxin heterologous translocation of beta-lactamase and roles of individual effector domains on cytoskeleton dynamics.

    Science.gov (United States)

    Dolores, Jazel S; Agarwal, Shivani; Egerer, Martina; Satchell, Karla J F

    2015-02-01

    The Vibrio cholerae MARTXVc toxin delivers three effector domains to eukaryotic cells. To study toxin delivery and function of individual domains, the rtxA gene was modified to encode toxin with an in-frame beta-lactamase (Bla) fusion. The hybrid RtxA::Bla toxin was Type I secreted from bacteria; and then Bla was translocated into eukaryotic cells and delivered by autoprocessing, demonstrating that the MARTXVc toxin is capable of heterologous protein transfer. Strains that produce hybrid RtxA::Bla toxins that carry one effector domain in addition to Bla were found to more efficiently translocate Bla. In cell biological assays, the actin cross-linking domain (ACD) and Rho-inactivation domain (RID) are found to cross-link actin and inactivate RhoA, respectively, when other effector domains are absent, with toxin autoprocessing required for high efficiency. The previously unstudied alpha-beta hydrolase domain (ABH) is shown here to activate CDC42, although the effect is ameliorated when RID is also present. Despite all effector domains acting on cytoskeleton assembly, the ACD was sufficient to rapidly inhibit macrophage phagocytosis. Both the ACD and RID independently disrupted polarized epithelial tight junction integrity. The sufficiency of ACD but strong selection for retention of RID and ABH suggests these two domains may primarily function by modulating cell signaling.

  6. Genomic Sequence of Klebsiella pneumoniae IIEMP-3, a Vitamin B12-Producing Strain from Indonesian Tempeh.

    Science.gov (United States)

    Yulandi, Adi; Sugiokto, Febri Gunawan; Febrilina; Suwanto, Antonius

    2016-02-25

    Klebsiella pneumoniae strain IIEMP-3, isolated from Indonesian tempeh, is a vitamin B12-producing strain that exhibited a different genetic profile from pathogenic isolates. Here we report the draft genome sequence of strain IIEMP-3, which may provide insights on the nature of fermentation, nutrition, and immunological function of Indonesian tempeh.

  7. Research advancement in the molecular regulation mechanism on the expression of chromosomally-mediated AmpC beta-lactamase%染色体介导 AmpC β-内酰胺酶表达的分子调控机制的研究进展

    Institute of Scientific and Technical Information of China (English)

    赵付菊(综述); 赵虎(审校)

    2014-01-01

    细菌产生β-内酰胺酶引起临床抗感染治疗的失败已成为全球性的医疗保健问题,AmpC β-内酰胺酶(简称 AmpC 酶)是其中重要的一种,有关其诱导表达的分子机制的研究日渐更新,现就 AmpC 酶染色体介导的调控机制的研究现状进行综述。%Bacterial resistance to beta-lactamase antibiotics through producing beta-lactamase has become a worldwide healthy care problem.AmpC beta-lactamase (AmpC)is a major one of beta-lactamases.Extensive research has focused on the molecular regulation mechanism pertaining to induction.The recent researches on the regulation mechanism about the expression of chromosomally-mediated AmpC are reviewed.

  8. Environmental persistence of OXA-48-producing Klebsiella pneumoniae in a French intensive care unit.

    Science.gov (United States)

    Pantel, Alix; Richaud-Morel, Brigitte; Cazaban, Michel; Bouziges, Nicole; Sotto, Albert; Lavigne, Jean-Philippe

    2016-03-01

    The spread of carbapenemase-producing Gram-negative rods is an emerging global problem. This study describes the epidemiologic features of an outbreak caused by an environmental reservoir of OXA-48-producing Klebsiella pneumoniae caused by persistence of the bacteria during 20 months in an intensive care unit in France. This report emphasizes the importance of early environmental screening to interrupt the transmission of carbapenemase-producingEnterobacteriaceae.

  9. Nosocomial acquisition of methicillin-resistant Staphyloccocus aureus (MRSA and extended-spectrum beta-lactamase (ESBL Enterobacteriaceae in hospitalised patients: a prospective multicenter study

    Directory of Open Access Journals (Sweden)

    De Angelis Giulia

    2012-03-01

    Full Text Available Abstract Background The risk of acquisition of antibiotic resistant-bacteria during or shortly after antibiotic therapy is still unclear and it is often confounded by scarce data on antibiotic usage. Primary objective of the study is to compare rates of acquisition of methicillin-resistant Staphylococcus aureus and extended spectrum beta-lactamase-producing Enterobacteriaceae in hospitalised patients, after starting antibiotic therapy. Methods/Design The study, running in three European hospitals, is a multicenter, prospective, longitudinal, observational cohort study funded from the European Community's Seventh Framework Programme [FP7/2007-2013] within the project 'Impact of Specific Antibiotic Therapies on the prevalence of hUman host ResistaNt bacteria' (acronym SATURN. Nasal and rectal screening for methicillin-resistant Staphylococcus aureus and extended spectrum beta-lactamase-producing Enterobacteriaceae will be obtained at hospital admission, discharge, at antibiotic start (t0, within one hour and at the following intervals: day 3 (t1, 7 (t2, 15 (t3, and 30 (t4. Two nested case-control studies will be performed. The objective of the first study will be to define individual level of risk related to specific antibiotics. Patients acquiring methicillin-resistant Staphylococcus aureus and extended spectrum beta-lactamase-producing Enterobacteriaceae (cases will be compared with patients not acquiring antibiotic-resistant strains after starting antibiotic therapy (controls; ratio 1:4. To define the impact of antibiotics on new acquisition of target antibiotic-resistant bacteria, a second nested case-control study will be done (ratio 1:4. Control group will be selected among patients not receiving antibiotics, admitted in the same ward on the day of the corresponding case, with negative cultures at admission. Epidemiological, clinical and microbiological data will be prospective collected. Discussion The rationale of this study is to better

  10. Rapid discrimination of Klebsiella pneumoniae carbapenemase 2-producing and non-producing Klebsiella pneumoniae strains using near-infrared spectroscopy (NIRS) and multivariate analysis.

    Science.gov (United States)

    Marques, Aline S; Moraes, Edgar P; Júnior, Miguel A A; Moura, Andrew D; Neto, Valter F A; Neto, Renato M; Lima, Kássio M G

    2015-03-01

    Klebsiella pneumoniae Carbapenemase (KPC-2)-producing and non-producing Klebsiella pneumoniae (KP) have rapidly disseminated worldwide, challenging the diagnostics of Gram-negative infections. We evaluate the potential of a novel non-destructive and rapid method based on Near-Infrared Spectroscopic (NIRS) and multivariate analysis for distinguishing KPC-2-producing and non-producing KP. Thirty-nine NIRS spectra (24 KPC-2-producing KP, 15 KPC-2 non-producing KP) were acquired; different pre-processing methods such as baseline correction, derivative and Savitzky-Golay smoothing were performed. A spectral region fingerprint was achieved after using genetic algorithm-linear discriminant analysis (GA-LDA) and successive projection algorithm (SPA-LDA) algorithms for variable selection. The variables selected were then used for discriminating the microorganisms.Accuracy test results including sensitivity and specificity were determined. Sensitivity in KPC-2 producing and non-producing KP categories was 66.7% and 75%, respectively, using a SPA-LDA model with 66 wavenumbers. The resulting GA-LDA model successfully classified both microorganisms with respect to their "fingerprints" using only 39 wavelengths. Sensitivity in KPC-2 producing category was moderate(≈66.7%) using a GA-LDA model. However, sensitivity in KPC-2 non-producing category using GA-LDA accurately predicted the correct class (with 100% accuracy). As100% accuracy was achieved, this novel approach identifies potential biochemical markers that may have a relation with microbial functional roles and means of rapid identification of KPC-2 producing and non-producing KP strains.

  11. Perianal Abscess and Proctitis by Klebsiella pneumoniae.

    Science.gov (United States)

    Jeong, Woo Shin; Choi, Sung Youn; Jeong, Eun Haeng; Bang, Ki Bae; Park, Seung Sik; Lee, Dae Sung; Park, Dong Il; Jung, Yoon Suk

    2015-01-01

    Klebsiella pneumoniae (K. pneumoniae) can at times cause invasive infections, especially in patients with diabetes mellitus and a history of alcohol abuse. A 61-year-old man with diabetes mellitus and a history of alcohol abuse presented with abdominal and anal pain for two weeks. After admission, he underwent sigmoidoscopy, which revealed multiple ulcerations with yellowish exudate in the rectum and sigmoid colon. The patient was treated with ciprofloxacin and metronidazole. After one week, follow up sigmoidoscopy was performed owing to sustained fever and diarrhea. The lesions were aggravated and seemed webbed in appearance because of damage to the rectal mucosa. Abdominal computed tomography and rectal magnetic resonance imaging were performed, and showed a perianal and perirectal abscess. The patient underwent laparoscopic sigmoid colostomy and perirectal abscess incision and drainage. Extended-spectrum beta-lactamase-producing K. pneumoniae was identified in pus culture. The antibiotics were switched to ertapenem. He improved after surgery and was discharged. K. pneumoniae can cause rapid invasive infection in patients with diabetes and a history of alcohol abuse. We report the first rare case of proctitis and perianal abscess caused by invasive K. pneumoniae infection.

  12. Influence of the bacterial phenotypes on the clinical manifestations in Klebsiella pneumoniae bacteremia patients: A retrospective cohort study.

    Science.gov (United States)

    Togawa, Atsushi; Toh, Hiromi; Onozawa, Kyoko; Yoshimura, Michinobu; Tokushige, Chiemi; Shimono, Nobuyuki; Takata, Tohru; Tamura, Kazuo

    2015-07-01

    Ninety-four episodes of Klebsiella pneumoniae bloodstream infection were identified at a university hospital in Japan. After excluding extended-spectrum beta lactamase-producing strains, 83 blood isolates from these patients were assayed in terms of their bacterial phenotypes such as the mucoid and hypermucoviscosity phenotypes. Bacterial phenotypes were correlated with the patients' clinical manifestations. The hypermucoviscosity phenotype was significantly associated with septic shock at the onset of infections (odds ratio, 15.92; 95% confidence interval, 1.27-468.12), but was not associated with liver abscess formation. Mortality was determined by the presence of septic shock. RmpA gene was associated with the induction of the hypermucoviscosity phenotype. These results reveal unique roles of bacterial phenotypes on the patient's clinical condition in K. pneumoniae bacteremia.

  13. First Isolate of KPC-2-Producing Klebsiella pneumonaie Sequence Type 23 from the Americas

    Science.gov (United States)

    Cejas, Daniela; Fernández Canigia, Liliana; Rincón Cruz, Giovanna; Elena, Alan X.; Maldonado, Ivana; Gutkind, Gabriel O.

    2014-01-01

    KPC-2-producing Klebsiella pneumoniae isolates mainly correspond to clonal complex 258 (CC258); however, we describe KPC-2-producing K. pneumoniae isolates belonging to invasive sequence type 23 (ST23). KPC-2 has scarcely been reported to occur in ST23, and this report describes the first isolation of this pathogen in the Americas. Acquisition of resistant markers in virulent clones could mark an evolutionary step toward the establishment of these clones as major nosocomial pathogens. PMID:25031447

  14. Presence of ESBL/AmpC-producing Escherichia coli in the broiler production pyramid: a descriptive study.

    NARCIS (Netherlands)

    Dierikx, C.M.; Goot, van der J.A.; Smith, H.E.; Kant, A.; Mevius, D.J.

    2013-01-01

    Broilers and broiler meat products are highly contaminated with extended spectrum beta-lactamase (ESBL) or plasmid-mediated AmpC beta-lactamase producing Escherichia coli and are considered to be a source for human infections. Both horizontal and vertical transmission might play a role in the presen

  15. Expression, purification, crystallization, and preliminary X-ray crystallographic analysis of OXA-17, an extended-spectrum {beta}-lactamase conferring severe antibiotic resistance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. H., E-mail: msgjhlee@mju.ac.kr; Sohn, S. G., E-mail: sgsohn@mju.ac.kr; Jung, H. I., E-mail: jhinumber1@hanmail.net; An, Y. J., E-mail: anyj0120@hanmail.net; Lee, S. H., E-mail: sangheelee@mju.ac.kr [Myongji University, Drug Resistance Proteomics Laboratory, Department of Biological Sciences (Korea, Republic of)

    2013-07-15

    OXA-17, an extended-spectrum {beta}-lactamase (ESBL) conferring severe antibiotic resistance, hydrolytically inactivates {beta}-lactam antibiotics, inducing a lack of eradication of pathogenic bacteria by oxyimino {beta}-lactams and not helping hospital infection control. Thus, the enzyme is a potential target for developing antimicrobial agents against pathogens producing ESBLs. OXA-17 was purified and crystallized at 298 K. X-ray diffraction data from OXA-17 crystal have been collected to 1.85 A resolution using synchrotron radiation. The crystal of OXA-17 belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 48.37, b = 101.12, and c = 126.07 A. Analysis of the packing density shows that the asymmetric unit probably contains two molecules with a solvent content of 54.6%.

  16. Molecular characterization of a carbapenem-hydrolyzing class A beta-lactamase, SFC-1, from Serratia fonticola UTAD54.

    Science.gov (United States)

    Henriques, Isabel; Moura, Alexandra; Alves, Artur; Saavedra, Maria José; Correia, António

    2004-06-01

    An environmental isolate of Serratia fonticola resistant to carbapenems contains a gene encoding a class A beta-lactamase with carbapenemase activity. The enzyme was designated SFC-1. The bla(SFC-I) gene is contained in the chromosome of S. fonticola UTAD54 and is absent from other S. fonticola strains.

  17. Method for phenotypic detection of extended-spectrum beta-lactamases in enterobacter species in the routine clinical setting

    NARCIS (Netherlands)

    Stuart, J.C.; Diederen, B.; Al Naiemi, N.; Fluit, A.; Arents, N.; Thijsen, S.; Vlaminckx, B.; Mouton, J.W.; Leverstein-van Hall, M.

    2011-01-01

    In 271 Enterobacter blood culture isolates from 12 hospitals, extended-spectrum beta-lactamase (ESBL) prevalence varied between 0% and 30% per hospital. High prevalence was associated with dissemination, indicating the potential relevance of infection control measures. Screening with cefepime or Vit

  18. Studies of Antibiotic Resistance of Beta-Lactamase Bacteria under Different Nutrition Limitations at the Single-Cell Level.

    Science.gov (United States)

    Wang, Ying; Ran, Min; Wang, Jun; Ouyang, Qi; Luo, Chunxiong

    2015-01-01

    Drug resistance involves many biological processes, including cell growth, cell communication, and cell cooperation. In the last few decades, bacterial drug resistance studies have made substantial progress. However, a major limitation of the traditional resistance study still exists: most of the studies have concentrated on the average behavior of enormous amounts of cells rather than surveying single cells with different phenotypes or genotypes. Here, we report our study of beta-lactamase bacterial drug resistance in a well-designed microfluidic device, which allows us to conduct more controllable experiments, such as controlling the nutrient concentration, switching the culture media, performing parallel experiments, observing single cells, and acquiring time-lapse images. By using GFP as a beta-lactamase indicator and acquiring time-lapse images at the single-cell level, we observed correlations between the bacterial heterogeneous phenotypes and their behavior in different culture media. The feedback loop between the growth rate and the beta-lactamase production suggests that the beta-lactamase bacteria are more resistant in a rich medium than in a relatively poor medium. In the poorest medium, the proportion of dormant cells may increase, which causes a lower death rate in the same generation. Our work may contribute to assaying the antibiotic resistance of pathogenic bacteria in heterogeneous complex media.

  19. Pseudomonas aeruginosa biofilms exposed to imipenem exhibit changes in global gene expression and beta-lactamase and alginate production

    DEFF Research Database (Denmark)

    Bagge, N.; Schuster, M.; Hentzer, Morten

    2004-01-01

    . As expected, the most strongly induced gene was ampC, which codes for chromosomal beta-lactamase. We also found that genes coding for alginate biosynthesis were induced by exposure to imipenem. Alginate production is correlated to the development of impaired lung function, and P. aeruginosa strains isolated...

  20. Evaluation of phenotypic tests for the detection of AmpC beta-lactamase in clinical isolates of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Deepika Handa

    2013-01-01

    Full Text Available Background: AmpC beta lactamases are cephalosporinases that confer resistance to a wide range of beta lactam drugs thereby causing serious therapeautic problem. As there are no CLSI guidelines for detection of AmpC mediated resistance in Gram negative clinical isolates and it may pose a problem due to misleading results, especially so in phenotypic tests. Although cefoxitin resistance is used as a screening test, it does not reliably indicate AmpC production. Materials and Methods: We planned a study to determine the occurrence of AmpC beta lactamase in hospital and community, clinical isolates of Escherichia coli and simultaneously evaluate different phenotypic methods for detection of AmpC beta lactamases. Results: It was observed that 82.76% isolates were ESBL positive and 59% were cefoxitin screen positive. Using phenotypic confirmatory tests the occurrence of Amp C beta lactamases was found to be 40% and 39% by inhibitor based method using boronic acid (IBM and modified three dimensional test (M3D respectively. Conclusion: Both the test showed concordant result. Co-production was observed in 84.62% isolates Screening of ESBL and Amp C can be done in routine clinical microbiology laboratory using aztreonam and IBM respectively as it is a simple, rapid and technically less demanding procedure which can be used in all clinical laboratories.

  1. Diversity of CTX-M beta-lactamases and their promoter regions from Enterobacteriaceae isolated in three Parisian hospitals.

    Science.gov (United States)

    Saladin, Michèle; Cao, Van Thi Bao; Lambert, Thierry; Donay, Jean-Luc; Herrmann, Jean-Louis; Ould-Hocine, Zahia; Verdet, Charlotte; Delisle, Françoise; Philippon, Alain; Arlet, Guillaume

    2002-04-01

    Nine clinical isolates of Enterobacteriaceae (six Escherichia coli and three Proteus mirabilis) isolated in three Parisian hospitals between 1989 and 2000 showed a particular extended-spectrum cephalosporin-resistance profile characterized by resistance to cefotaxime and aztreonam but not to ceftazidime. CTX-M-1, CTX-M-2, CTX-M-9, CTX-M-14 and two novel plasmid-mediated CTX-M beta-lactamases (CTX-M-20, and CTX-M-21) were identified by polymerase chain reaction and isoelectric focusing (pI>8) and were associated in eight cases with TEM-1 (pI=5.4) or TEM-2 (pI=5.6) beta-lactamases. We used internal ISEcp1 and IS26 forward primers and the CTX-M consensus reverse primer to characterize the CTX-M beta-lactamase promoter regions and showed their high degree of structure diversity. We found upstream of some bla(CTX-M) genes, a 266-bp sequence 100% identical to the sequence upstream of the Kluyvera ascorbata beta-lactamase gene, suggesting that this chromosomal enzyme is the progenitor of the CTX-M-2/5 cluster.

  2. Detection of Extended Spectrum Beta-Lactamases Resistance Genes among Bacteria Isolated from Selected Drinking Water Distribution Channels in Southwestern Nigeria

    Science.gov (United States)

    Ogunjobi, Adeniyi A.

    2016-01-01

    Extended Spectrum Beta-Lactamases (ESBL) provide high level resistance to beta-lactam antibiotics among bacteria. In this study, previously described multidrug resistant bacteria from raw, treated, and municipal taps of DWDS from selected dams in southwestern Nigeria were assessed for the presence of ESBL resistance genes which include blaTEM, blaSHV, and blaCTX by PCR amplification. A total of 164 bacteria spread across treated (33), raw (66), and municipal taps (68), belonging to α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Flavobacteriia, Bacilli, and Actinobacteria group, were selected for this study. Among these bacteria, the most commonly observed resistance was for ampicillin and amoxicillin/clavulanic acid (61 isolates). Sixty-one isolates carried at least one of the targeted ESBL genes with blaTEM being the most abundant (50/61) and blaCTX being detected least (3/61). Klebsiella was the most frequently identified genus (18.03%) to harbour ESBL gene followed by Proteus (14.75%). Moreover, combinations of two ESBL genes, blaSHV + blaTEM or blaCTX + blaTEM, were observed in 11 and 1 isolate, respectively. In conclusion, classic blaTEM ESBL gene was present in multiple bacterial strains that were isolated from DWDS sources in Nigeria. These environments may serve as foci exchange of genetic traits in a diversity of Gram-negative bacteria. PMID:27563674

  3. Ventilator-associated pneumonia caused by carbapenem-resistant Enterobacteriaceae carrying multiple metallo-beta-lactamase genes

    Directory of Open Access Journals (Sweden)

    Dwivedi Mayank

    2009-07-01

    Full Text Available Context: Ventilator-associated pneumonia (VAP is a leading nosocomial infection in the intensive care unit (ICU. Members of Enterobacteriaceae are the most common causative agents and carbapenems are the most commonly used antibiotics. Metallo-beta-lactamase (MBL production leading to treatment failure may go unnoticed by routine disc diffusion susceptibility testing. Moreover, there is not much information on association of MBL-producing Enterobacteriaceae with ICU-acquired VAP. Therefore, a study was undertaken to find out the association of MBL-producing Enterobacteriaceae with VAP. Settings: This study was conducted in a large tertiary care hospital of North India with an eight-bed critical care unit. Materials and Methods: The respiratory samples (bronchoalveolar lavage, protected brush catheter specimens and endotracheal or transtracheal aspirates obtained from VAP patients (during January 2005-December 2006 were processed, isolated bacteria identified and their antibiotic susceptibilities tested as per standard protocols. The isolates of Enterobacteriaceae resistant to carbapenem were subjected to phenotypic and genotypic tests for the detection of MBLs. Results: Twelve of 64 isolates of Enterobacteriaceae were detected as MBL producers, bla IMP being the most prevalent gene. Additionally, in three strains, simultaneous coexistence of multiple MBL genes was detected. Conclusion: The coexistence of multiple MBL genes in Enterobacteriaceae is an alarming situation. As MBL genes are associated with integrons that can be embedded in transposons, which in turn can be accommodated on plasmids thereby resulting in a highly mobile genetic apparatus, the further spread of these genes in different pathogens is likely to occur.

  4. Transfer of a gonococcal beta-lactamase plasmid to conjugation-deficient Neisseria cinerea strains by transformation.

    Science.gov (United States)

    Genco, C A; Clark, V L

    1988-12-01

    We have previously shown that some strains of Neisseria cinerea can serve as recipients in conjugation (Con+) with Neisseria gonorrhoeae while others cannot (Con-). To determine if a replication defect contributes to the inability of certain strains of N. cinerea to serve as recipients in conjugation, we attempted to introduce a naturally occurring gonococcal beta-lactamase plasmid into N. cinerea by transformation. Various methods were employed, and all proved unsuccessful. Since specific sequences are required for DNA uptake in transformation of N. gonorrhoeae, we constructed a number of hybrid plasmids containing N. cinerea chromosomal DNA inserted into the N. gonorrhoeae/Escherichia coli beta-lactamase shuttle vector, pLES2. When nine randomly selected plasmids with inserts were used to transform an N. cinerea strain which did not accept the gonococcal beta-lactamase plasmid by conjugation, transformants were observed with four of the hybrid plasmids. The presence of one of the hybrid plasmids, pCAG9, in transformants was confirmed by agarose gel electrophoresis, Southern hybridization, and beta-lactamase production. When an N. gonorrhoeae donor strain containing pCAG9 was used in conjugation with several N. cinerea strains, only those strains that were previously shown to act as recipients could accept and maintain pCAG9. The ability of pCAG9 and the other three hybrid plasmids to transform Con- strains demonstrates that the beta-lactamase plasmid can replicate in Con- strains, and, therefore, the Con- phenotype is due to a block in some other stage of the conjugation process.

  5. Ligand-Dependent Disorder of Loop Observed in Extended-Spectrum SHV-Type beta-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    J Sampson; W Ke; C Bethel; S Pagadala; M Nottingham; R Bonomo; J Buynak; F van den Akker

    2011-12-31

    Among Gram-negative bacteria, resistance to {beta}-lactams is mediated primarily by {beta}-lactamases (EC 3.2.6.5), periplasmic enzymes that inactivate {beta}-lactam antibiotics. Substitutions at critical amino acid positions in the class A {beta}-lactamase families result in enzymes that can hydrolyze extended-spectrum cephalosporins, thus demonstrating an 'extended-spectrum' {beta}-lactamase (ESBL) phenotype. Using SHV ESBLs with substitutions in the {Omega} loop (R164H and R164S) as target enzymes to understand this enhanced biochemical capability and to serve as a basis for novel {beta}-lactamase inhibitor development, we determined the spectra of activity and crystal structures of these variants. We also studied the inactivation of the R164H and R164S mutants with tazobactam and SA2-13, a unique {beta}-lactamase inhibitor that undergoes a distinctive reaction chemistry in the active site. We noted that the reduced K{sub i} values for the R164H and R164S mutants with SA2-13 are comparable to those with tazobactam (submicromolar). The apo enzyme crystal structures of the R164H and R164S SHV variants revealed an ordered {Omega} loop architecture that became disordered when SA2-13 was bound. Important structural alterations that result from the binding of SA2-13 explain the enhanced susceptibility of these ESBL enzymes to this inhibitor and highlight ligand-dependent {Omega} loop flexibility as a mechanism for accommodating and hydrolyzing {beta}-lactam substrates.

  6. Community-Acquired Pyelonephritis in Pregnancy Caused by KPC-Producing Klebsiella pneumoniae

    Science.gov (United States)

    Khatri, Asma; Naeger Murphy, Nina; Wiest, Peter; Osborn, Melissa; Garber, Kathleen; Hecker, Michelle; Hurless, Kelly; Rudin, Susan D.; Jacobs, Michael R.; Kalayjian, Robert C.; Salata, Robert A.; van Duin, David; Harris, Patrick N. A.

    2015-01-01

    Carbapenem-resistant Enterobacteriaceae (CRE) usually infect patients with significant comorbidities and health care exposures. We present a case of a pregnant woman who developed community-acquired pyelonephritis caused by KPC-producing Klebsiella pneumoniae. Despite antibiotic treatment, she experienced spontaneous prolonged rupture of membranes, with eventual delivery of a healthy infant. This report demonstrates the challenge that CRE may pose to the effective treatment of common infections in obstetric patients, with potentially harmful consequences to maternal and neonatal health. PMID:26185273

  7. Mother-To-Child Transmission of KPC Carbapenemase-Producing Klebsiella Pneumoniae at Birth.

    Science.gov (United States)

    Bonfanti, Paolo; Bellù, Roberto; Principe, Luigi; Caramma, Ilaria; Condò, Manuela; Giani, Tommaso; Rossolini, Gian Maria; Luzzaro, Francesco

    2017-02-01

    We report on a mother-to-child transmission of KPC carbapenemase-producing Klebsiella pneumoniae at birth followed by subsequent cases in the neonatal intensive care unit. Molecular analysis of isolates showed production of KPC-3 enzyme. The only potential risk factor identified for the mother was previous activity as a caregiver. Present findings suggest consideration of proactive surveillance in pregnant women with risk factors for colonization.

  8. Emergence of co-production of plasmid-mediated AmpC beta-lactamase and ESBL in cefoxitin-resistant uropathogenic Escherichia coli.

    Science.gov (United States)

    Ghosh, B; Mukherjee, M

    2016-09-01

    Plasmid-mediated AmpC (pAmpC) and ESBL co-production was detected in Escherichia coli a major etiologic agent of urinary tract infection. Isolates resistant to cefoxitin by CLSI methodology were tested for pAmpC beta-lactamase using phenylboronic acid and ESBLs by combined disk diffusion method. pAmpC/ESBL genes were characterized by PCR and sequencing. Transconjugation experiments were done to study the transfer of pAmpC and ESBL production from clinical isolates as donor to E. coli J53 AziR as recipient. Incompatibility groups of transmissible plasmids were classified by PCR-based replicon typing (PBRT). Among 148 urine culture positive isolates, E. coli was reported in 39.86 % (59/148), with 93.22 % (55/59) of cefoxitin resistance. pAmpC production was detected in 25, with varied distribution of blaCMY-2 and blaDHA-1type genes alone (n = 13 and 7 respectively) or in combination (n = 5). ESBL co-production was observed in 88 % (22/25) of pAmpC producing isolates with predominance of blaTEM (n = 20). Twenty-three transconjugants showed transmission of pAmpC-and ESBL-resistant genes with co-carriage of blaCMY-2 and blaTEM (n = 15) in plasmids of IncF type (n = 9) being predominant, followed by IncI1 (n = 4) and IncH1 (n = 2) in combination. All clinical isolates were clonally diverse. Resistance against different beta-lactams in uropathogenic E. coli has been an emerging concern in resource- poor countries such as India. Knowledge on the occurrence of AmpC beta-lactamases and ESBL amongst this pathogen and its transmission dynamics may aid in hospital infection control.

  9. Caracterização de beta-lactamases em Serratia fonticola

    OpenAIRE

    Henriques, Isabel

    2001-01-01

    A estirpe Serratia fonticola UTAD54 foi isolada no âmbito de um estudo realizado com o objectivo de analisar a presença e disseminação de genes de resistência a antibióticos, em bactérias de águas de consumo. Verificou-se que esta estirpe é resistente a diversos antibióticos do grupo dos beta-lactâmicos, nomeadamente às penicilinas e aos carbapenemos. No âmbito deste estudo foi detectada a produção de uma metalo-beta-lactamase denominada SfhI, responsável pelo fenótipo de re...

  10. Vers l'évolution d'une DD-peptidase en beta-lactamase

    OpenAIRE

    Labarbe, Carole

    2006-01-01

    Les DD-peptidases sont des enzymes impliquées dans la synthèse de la paroi bactérienne. Elles sont aussi appelées "Penicillin Binding Proteins" (PBPs) car elles forment des acyl-enzymes stables avec des antibiotiques de type beta-lactames comme la pénicilline, la stabilité de ces complexes étant à l'origine de l'effet antibiotique. Certaines bactéries sont résistantes aux b-lactames grâce à la production de beta-lactamases, capables d'hydrolyser ces antibiotiques jusqu'à 10E8 fois plus rapide...

  11. Dynamics and spatial distribution of beta-lactamase expression in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Bagge, N.; Hentzer, Morten; Andersen, Jens Bo

    2004-01-01

    The development of resistance to beta-lactam antibiotics is a problem in the treatment of chronic Pseudomonas aeruginosa infection in the lungs of patients with cystic fibrosis. The main resistance mechanism is high-level expression of the chromosomally encoded AmpC beta-lactamase of P. aeruginosa...... cells growing in biofilms. Several genes have been shown to influence the level of ampC expression, but little is known about the regulation of ampC expression in P. aeruginosa biofilms. To study the expression of ampC in P. aeruginosa biofilms, we constructed a reporter that consisted of the fusion...... of the ampC promoter to gfp(ASV) encoding an unstable version of the green fluorescent protein. In vitro biofilms of P. aeruginosa were exposed to the beta-lactam antibiotics imipenem and ceftazidime. Sub-MICs of imipenem significantly induced the monitor system of the biofilm bacteria in the peripheries...

  12. Carbapenemase-Producing Klebsiella pneumoniae in Romania: A Six-Month Survey.

    Science.gov (United States)

    Lixandru, Brandusa Elena; Cotar, Ani Ioana; Straut, Monica; Usein, Codruta Romanita; Cristea, Dana; Ciontea, Simona; Tatu-Chitoiu, Dorina; Codita, Irina; Rafila, Alexandru; Nica, Maria; Buzea, Mariana; Baicus, Anda; Ghita, Mihaela Camelia; Nistor, Irina; Tuchiluş, Cristina; Indreas, Marina; Antohe, Felicia; Glasner, Corinna; Grundmann, Hajo; Jasir, Aftab; Damian, Maria

    2015-01-01

    This study presents the first characterization of carbapenem-non-susceptible Klebsiella pneumoniae isolates by means of a structured six-month survey performed in Romania as part of an Europe-wide investigation. Klebsiella pneumoniae clinical isolates from different anatomical sites were tested for antibiotic susceptibility by phenotypic methods and confirmed by PCR for the presence of four carbapenemase genes. Genome macrorestriction fingerprinting with XbaI was used to analyze the relatedness of carbapenemase-producing Klebsiella pneumoniae isolates collected from eight hospitals. Among 75 non-susceptible isolates, 65 were carbapenemase producers. The most frequently identified genotype was OXA-48 (n = 51 isolates), eight isolates were positive for blaNDM-1 gene, four had the blaKPC-2 gene, whereas two were positive for blaVIM-1. The analysis of PFGE profiles of OXA-48 and NDM-1 producing K. pneumoniae suggests inter-hospitals and regional transmission of epidemic clones. This study presents the first description of K. pneumoniae strains harbouring blaKPC-2 and blaVIM-1 genes in Romania. The results of this study highlight the urgent need for the strengthening of hospital infection control measures in Romania in order to curb the further spread of the antibiotic resistance.

  13. 产I型新德里金属β-内酰胺酶耐药菌的研究概况及应对措施%Introduction and Fighting Tactics of Produce New Delhi Metallo-beta-lactamase (NDM-1) Multi-drug Resistant Bacteria

    Institute of Scientific and Technical Information of China (English)

    林雯; 周光泉; 汪莉; 李巧玲; 邓建平

    2011-01-01

    The New Delhi Metallo-β-lactamase 1 (NDM 1) has been initially identified in multidrug-resistant Escherichia coli and Klebsiella pneumoniae isolates in 2008. Today it could be found in India ,UK ,USA ,Canada ,the Netherlands ,Australia and China. There was one case of NDM-1 positive bacteria at least which was resistant to all known antibiotics so far. This paper briefly discussed the discovery ,development,drug resistance, genetic character of NDM 1 bacteria and the corresponding strategies to precaution and control the NDM-1 positive bacteria.%2008年首次在大肠埃希菌和肺炎克雷伯菌中确认了Ⅰ型新德里金属β-内酰胺酶(New Delhi Metalloβ-lactamase 1,NDM-1).目前产NDM-1酶细菌在印度、英国、美国、加拿大、荷兰、澳大利亚以及中国等国均有报道.研究发现至少一例NDM-1阳性菌对所有已知的抗生素具有耐药性.该文简要介绍了NDM-1耐药菌的发现、发展过程及其耐药性情况,基因特点以及NDM-1阳性菌的应对措施.

  14. Bioflocculant Produced by Klebsiella sp. MYC and Its Application in the Treatment of Oil-field Produced Water

    Institute of Scientific and Technical Information of China (English)

    YUE Lixi; MA Chunling; CHI Zhenming

    2006-01-01

    Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20gL 1, KH2PO4 2gL-1, K2HPO4 5gL-1, (NH4)2SO4 0.2gL-1, urea 0.5gL-1 and yeast extract 0.5gL 1, the initial pH being 5.5. When the suspension of kaolin clay was treated with0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0 % in the presence of 500 mg L-1 CaCl2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0 - 9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environm ent-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment.

  15. Isolation of NDM-1-producing Klebsiella pnemoniae in Ireland, July 2011.

    LENUS (Irish Health Repository)

    McDermott, H

    2012-01-01

    We report the identification of New Delhi metallo-betalactamase 1 (NDM-1)-producing Klebsiella pnemoniae in Ireland. The organism was resistant to multiple antibiotic classes, including carbapenems, and PCR and sequencing confirmed the presence of the blaNDM-1 gene, carried on a 98 kb plasmid. The organism was isolated from an infant, who was born in India and moved to Ireland at the age of four months. This is the first reported isolation of an NDM-1-producing Enterobacteriaceae strain in Ireland.

  16. Antibacterial activity and PK/PD of ceftriaxone against penicillin-resistant Streptococcus pneumoniae and beta-lactamase-negative ampicillin-resistant Haemophilus influenzae isolates from patients with community-acquired pneumonia.

    Science.gov (United States)

    Ohno, Akira; Ishii, Yoshikazu; Kobayashi, Intetsu; Yamaguchi, Keizo

    2007-10-01

    The suitability of ceftriaxone for penicillin-resistant Streptococcus pneumoniae (PRSP) and ampicillin-resistant Haemophilus influenzae (especially beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae) and the relationship between in vitro antimicrobial activities and pharmacokinetic parameters were evaluated. The values for percentage of time above the MIC (%T>MIC) for ceftriaxone, cefotiam, flomoxef, sulbactam/cefoperazone, sulbactam/ampicillin, and meropenem, using 400 S. pneumoniae isolates and 430 H. influenzae isolates from patients with community-acquired pneumonia (CAP) from more than 100 geographically diverse medical centers during January to July of 2005, were calculated by measuring the MIC for each isolate and by using patameters of pharmacokinetics. A broth microdilution method was used to determine the MIC, using the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Meropenem showed the lowest MIC against penicillin-susceptible S. pneumoniae, followed by sulbactam/cefoperazone and ceftriaxone. Ceftriaxone had the best activity against penicillin-resistant S. pneumoniae and beta-lactamase-negative and beta-lactamase-producing ampicillin-resistant H. influenzae. Ceftriaxone was unique, showing a long elimination half-life and low MIC values where its serum level duration time was above the MIC for longer than other cephalosporins. Accordingly, the %T>MIC of ceftriaxone for a once-daily administration greatly exceeded the efficacy levels of those for the other antibacterial agents tested. Ceftriaxone has an excellent balance between in vitro antimicrobial activities and pharmacokinetic profiles; and therefore remains effective as a therapeutic agent against PRSP and BLNAR H. influenzae in CAP.

  17. Early onset Morganella morganii sepsis in a newborn infant with emergence of cephalosporin resistance caused by depression of AMPC beta-lactamase production..

    Science.gov (United States)

    Sinha, Ajay K; Kempley, Stephen T; Price, Elizabeth; Sharma, Bal K; Livermore, David M

    2006-04-01

    A preterm infant with early onset Morganella morganii sepsis was treated with cefotaxime and gentamicin after confirmation of antimicrobial susceptibility. The infant developed persistent ventriculitis caused by the emergence of a cefotaxime-resistant Morganella variant with derepression of its AmpC beta-lactamase. When choosing antibiotic therapy, the risk of development of resistance to cephalosporins should be considered in infections caused by M. morganii and other Gram-negative organisms with inducible AmpC beta-lactamases.

  18. Analysis of plasmid-mediated multidrug resistance in Escherichia coli and Klebsiella oxytoca isolates from clinical specimens in Japan.

    Science.gov (United States)

    Ode, Takashi; Saito, Ryoichi; Kumita, Wakako; Sato, Kenya; Okugawa, Shu; Moriya, Kyoji; Koike, Kazuhiko; Okamura, Noboru

    2009-10-01

    This study investigated the relationship of plasmid-mediated quinolone resistance (PMQR) and aminoglycoside resistance among oxyimino-cephalosporin-resistant Escherichia coli (n=46) and Klebsiella oxytoca (n=28) clinical isolates in Japan. Seventy-three isolates appeared to produce an extended-spectrum beta-lactamase (ESBL) and one K. oxytoca isolate produced IMP-1 metallo-beta-lactamase (MBL). Polymerase chain reaction (PCR) and sequencing confirmed that eight CTX-M-9/SHV-12-producing isolates, one IMP-1-producing K. oxytoca isolate, and six ESBL-positive E. coli isolates respectively possessed PMQR genes qnrA1, qnrB6, and aac(6')-Ib-cr. All qnr-positive isolates also carried either aac(6')-Ib or aac(6')-IIc aminoglycoside acetyltransferase genes. Resistance determinants to beta-lactams, quinolones and aminoglycosides were co-transferred with a plasmid of ca. 140 kb. The qnrA1 gene was located downstream of insertion sequence ISCR1 in complex class 1 integrons. A novel qnrA1-carrying class 1 integron with the cassette arrangement aac(6')-IIc-aadA2 as well as a unique class 1 integron with bla(IMP-1)-aac(6')-IIc cassettes on the plasmid carrying qnrB6 were found in K. oxytoca isolates. We describe the identification of qnrB6 and aac(6')-Ib-cr and the close association of qnr with aac(6')-Ib and aac(6')-IIc for the first time in clinical isolates producing ESBL or MBL in Japan.

  19. [Clinical assessment of novel ChromID ESBL agar plates for detection of ESBL producers in the family Enterobacteriaceae].

    Science.gov (United States)

    Kasuga, Eriko; Matsumoto, Takehisa; Hidaka, Eiko; Oguchi, Harumi; Kanai, Shinichiro; Oana, Kozue; Yamauchi, Kazuyoshi; Honda, Takayuki; Kawakami, Yoshiyuki

    2009-01-01

    Extended-Spectrum beta-Lactamase (ESBL)-producers in the family Enterobacteriaceae are recognized worldwide as nosocomial pathogens, however it is difficult to screen them in the routine laboratory processing. ChromID ESBL agar newly developed for screening ESBL-producing Enterobacteriaceae was released in Japan in April, 2007. We evaluated the clinical assessment of ChromID ESBL agar in routine microbiology laboratory. The 47 strains investigated were clinical isolates belonging to the family Enterobacteriaceae with the MICs of cefpodoxime greater than 2 mug/ml. The 27 ESBL-producers examined were comprising of 19 Escherichia coli, 3 Klebsiella oxytoca, 1 Citrobacter freundii, 3 Enterobacter cloacae, and 1 S. marcescens (ESBL group) and 20 ESBL non-producers consiating of 5 K. oxytoca, 1 Proteus mirabilis, 1 P. vlugaris, 2 Serratia marcescens, 8 C. freundii, 2 Enterobacter cloacae, and 1 E. aerogenes (non-ESBL group). Characterization of beta-lactamase genes was carried out by use of polymerase chain reaction. As the results, the sensitivity and the specificity of ChromID ESBL agar plates after incubation for 18 hours was 100% and 20%, respectively. It should be noted that the values of specificity was extremely low compared with those of the sensitivity. These findings clearly suggested that in cases of utilizing ChromID ESBL agar plates, it should be important to consider its characteristic properties, as even the ESBL-non-producers could grow on these media only when they were resistant to CPDX.

  20. STUDY ON SURGICAL SITE INFECTIONS CAUSED BY ESBL PRODUCING GRAM NEGATIVE BACTERIA

    Directory of Open Access Journals (Sweden)

    Rambabu

    2015-09-01

    Full Text Available Surgical site infections have been a major problem, because of the emergence of drug resistant bacteria, in particular B - lactamase producing bacteria. Extended spectrum beta lactamase producing gram negative organisms pose a great challenge in treatment o f SSI present study is aimed at determining multiple drug resistance in gram negative bacteria & to find out ESBL producers, in correlation with treatment outcome. A total of 120 wound infected cases were studied. Staphylococcus aureus was predominant bact erium - 20.Among gram negative bacteria, Pseudomonas species is predominant (14 followed by Escherichia coli (13 , Klebsiella species (12 , Proteus (9 Citrobacter (4 Providencia (2 & Acinetobacter species (2 . Out of 56 gramnegative bacteria isolated, 20 were i dentified as ESBL producers, which was statistically significant. Delay in wound healing correlated with infection by ESBL producers, which alarms the need of abstinence from antibiotic abuse

  1. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...

  2. Occurrence of extended-spectrum beta-lactamases in Enterobacteriaceae isolated from hospitalized patients in Curitiba, southern Brazil

    OpenAIRE

    Keite da Silva Nogueira; Ilma Hiroko Higuti; Agnaldo José do Nascimento; Larissa Bail Terasawa; Simone Oliveira; Adriana Pereira Matos; Helena Aguilar Peres Homem de Mello de Souza; Laura Lúcia Cogo; Libera Maria Dalla Costa

    2006-01-01

    Production of extended-spectrum beta-lactamases (ESBL) by enterobacteria is an important resistance mechanism against antimicrobial beta-lactamics. We tested 498 bacterial strains isolated from two tertiary-care teaching hospitals for ESBL production, using screening breakpoints for aztreonam and third generation cephalosporins, according to CLSI recommendations. Among these isolates, 155 were positive for the ESBL screening test, and 121 (78%) were confirmed by the clavulanic acid combinatio...

  3. The 1.4 Å Crystal Structure of the Class D [beta]-Lactamase OXA-1 Complexed with Doripenem

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Kyle D.; Karpen, Mary E.; Bonomo, Robert A.; Leonard, David A.; Powers, Rachel A.; (Grand Valley); (Case Western U.-Med)

    2010-01-12

    The clinical efficacy of carbapenem antibiotics depends on their resistance to the hydrolytic action of {beta}-lactamase enzymes. The structure of the class D {beta}-lactamase OXA-1 as an acyl complex with the carbapenem doripenem was determined to 1.4 {angstrom} resolution. Unlike most class A and class C carbapenem complexes, the acyl carbonyl oxygen in the OXA-1-doripenem complex is bound in the oxyanion hole. Interestingly, no water molecules were observed in the vicinity of the acyl linkage, providing an explanation for why carbapenems inhibit OXA-1. The side chain amine of K70 remains fully carboxylated in the acyl structure, and the resulting carbamate group forms a hydrogen bond to the alcohol of the 6{alpha}-hydroxyethyl moiety of doripenem. The carboxylate attached to the {beta}-lactam ring of doripenem is stabilized by a salt bridge to K212 and a hydrogen bond with T213, in lieu of the interaction with an arginine side chain found in most other {beta}-lactamase-{beta}-lactam complexes (e.g., R244 in the class A member TEM-1). This novel set of interactions with the carboxylate results in a major shift of the carbapenem's pyrroline ring compared to the structure of the same ring in meropenem bound to OXA-13. Additionally, bond angles of the pyrroline ring suggest that after acylation, doripenem adopts the {Delta}{sup 1} tautomer. These findings provide important insights into the role that carbapenems may have in the inactivation process of class D {beta}-lactamases.

  4. Commensal Enterobacteriaceae as reservoirs of extended-spectrum beta-lactamases, integrons and sul genes in Portugal

    Directory of Open Access Journals (Sweden)

    Elisabete eMachado

    2013-04-01

    Full Text Available Bacteria colonizing the human intestine have a relevant role in the spread of antimicrobial resistance. We investigated the faecal carriage of extended-spectrum beta-lactamase (ESBL-producing Enterobacteriaceae in healthy humans from Portugal and analysed the distribution of sul genes and class 1 and 2 integrons. Faecal samples (n=113 were recovered from healthy persons (North/Centre of Portugal, 2001-04 and plated on MacConkey agar with and without ceftazidime (1mg/L or cefotaxime (1mg/L. Isolates representing different morphotypes/plate and antibiotic susceptibility patterns (n=201 were selected. Isolates resistant to sulfonamides and/or streptomycin, gentamicin and trimethoprim were screened (PCR, sequencing for sul genes (sul1, sul2, sul3 and class 1 and 2 integrons. Presence of ESBLs was inferred using the DDST and further confirmed by PCR and sequencing. ESBL producers were selected for clonal analysis, plasmid characterization and conjugation assays by standard methods. ESBL-producing isolates were found in 1.8% (2/113 of samples, corresponding to Escherichia coli of phylogroups A (n=1 and B1 (n=1 carrying transferable blaCTX-M-14 and the new blaTEM-153, respectively. A 80kb IncK-blaCTX-M-14 was found, being highly related to that widely spread among CTX-M-14 producers of humans and animals from Portugal and other European countries. sul genes were found in 88% (22/25;sul2-60%, sul1-48%, sul3-4% of the sulfonamide resistant isolates. Class 1 integrons were more frequently found than class 2 (7% vs 3%. Interestingly, gene cassette arrangements within these platforms were identical to those commonly observed among Enterobacteriaceae from Portuguese food-producing animals, although aadA13 is here firstly described in Morganella morganii. These results reinforce the relevance of human commensal flora as reservoir of clinically relevant antibiotic resistance genes including blaESBLs, and highly transferable genetic platforms as IncK epidemic

  5. Noncovalent Interaction Energies in Covalent Complexes: TEM-1 beta-Lactamase and beta-Lactams

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun; Minasov, George; Shoichet, Brian K. (NWU)

    2010-03-08

    The class A {beta}-lactamase TEM-1 is a key bacterial resistance enzyme against {beta}-lactam antibiotics, but little is known about the energetic bases for complementarity between TEM-1 and its inhibitors. Most inhibitors form a covalent adduct with the catalytic Ser70, making the measurement of equilibriumconstants, and hence interaction energies, technically difficult. This study evaluates noncovalent interactions withincovalent complexes by examining the differential stability of TEM-1 and its inhibitor adducts. The thermal denaturation of TEM-1 follows a two-state, reversible model with a melting temperature (T{sub m}) of 51.6 C and a van't Hoff enthalpy of unfolding ({Delta}H{sub VH}) of 146.2 kcal/mol at pH 7.0. The stability of the enzyme changes on forming an inhibitor adduct. As expected, some inhibitors stabilize TEM-1; transition-state analogues increase the T{sub m} by up to 3.7 C(1.7 kcal/mol). Surprisingly, all {beta}-lactam covalent acyl-enzyme complexes tested destabilize TEM-1 significantly relative to the apoenzyme. For instance, the clinically used inhibitor clavulanic acid and the {beta}-lactamase-resistant {beta}-lactams moxalactam and imipenem destabilize TEM-1 by over 2.6 C (1.2 kcal/mol) in their covalent adducts. Based on the structure of the TEM-1/imipenem complex (Maveyraud et al., J Am Chem Soc 1998;120:9748-52), destabilization by moxalactam and imipenem is thought to be caused by a steric clash between the side-chain of Asn132 and the 6(7)-{alpha} group of these {beta}-lactams. To test this hypothesis, the mutant enzyme N132A was made. In contrast with wild-type, the covalent complexes between N132A and both imipenem and moxalactam stabilize the enzyme, consistent with the hypothesis. To investigate the structural bases of this dramatic change instability, the structure of N132A/imipenem was determined by X-ray crystallography. In the complex with N132A, imipenemadopts a very different conformation from that observed in the wild

  6. Isolation of KPC 3-producing Enterobacter aerogenes in a patient colonized by MDR Klebsiella pneumoniae.

    Science.gov (United States)

    Venditti, Carolina; Villa, Laura; Capone, Alessandro; Fortini, Daniela; D'Arezzo, Silvia; Nisii, Carla; Bordi, Eugenio; Puro, Vincenzo; Antonini, Mario; Carattoli, Alessandra; Cataldo, Maria Adriana; Petrosillo, Nicola; Di Caro, Antonino

    2016-10-01

    We describe the interspecies transmission of the plasmid-mediated blaKPC-3 gene, which confers carbapenem resistance, between clinically relevant gram-negative bacteria in a single patient. A KPC-3 producing Enterobacter aerogenes was isolated from a hospitalized patient previously colonized and then infected by a Klebsiella pneumoniae ST101 carrying the blaKPC-3 gene. The strains showed identical plasmids. Since intense horizontal exchanges among bacteria can occur in the gut, clinicians should be aware that patients colonized by carbapenem-resistant K. pneumoniae could become carriers of other carbapenem-resistant Enterobacteriaceae.

  7. SHV-type extended-spectrum beta-lactamase (ESBL) are encoded in related plasmids from enterobacteria clinical isolates from Mexico beta-Lactamasas de espectro extendido (BLEE) tipo SHV están codificadas en plásmidos relacionados en aislamientos clínicos de enterobacterias en México

    OpenAIRE

    Ulises Garza-Ramos; Esperanza Martínez-Romero; Jesús Silva-Sánchez

    2007-01-01

    OBJECTIVE: In this work we report the molecular characterization of beta-lactam antibiotics resistance conferred by genes contained in plasmids from enterobacteria producing extended-spectrum beta-lactamases (ESBL). MATERIAL AND METHODS: Fourteen enterobacterial clinical isolates selected from a group of strains obtained from seven different hospitals in Mexico during 1990-1992 and 1996-1998 were analyzed at the Bacterial Resistance Laboratory (National Institute Public Health, Cuernavaca). M...

  8. Investigation of klebsiella pneumoniae-producing metallo-β-lactamases IMP-4%产金属β-内酰胺酶IMP-4肺炎克雷伯菌调查分析

    Institute of Scientific and Technical Information of China (English)

    韩秀峰; 苏旭; 井良义; 刘广文; 董杰; 王志锐; 朱韬; 穆祥弟

    2011-01-01

    OBJECTIVE To analyze production of metallo-β-1actamases (MBLs) and carbapenemase in one imipenem-resistant Klebsiella pneumoniae isolate. METHODS Two strains of K. pneumoniae were isolated from samples of urine and sputum respectively from female inpatient admitted to Tianjin Hongqiao hospital in Apr,2010. MIC method was used to perform the in vitro antimicrobial susceptibility testing for the isolates, and extended-spectrum beta-lactamase (ESBLs) production was tested for the isolates according to CLSI criteria. PCR were used to amplify MBLs genes, blaIMP and blaVIM, and KPC gene. PCR products were sequenced and analyzed. RESULTS The isolates showed multi-drug resistance. The isolate from urine (HQU) was resistant to imipenem and the isolate from sputum was not. Both of the isolates were producing ESBLs. K. pneumoniae HQU was carrying blaIMP-4 located in plasmid. The blaVIM and KPC genes were not detected out. CONCLUSION The presence of MBLs, IMP-4, in K. pneumoniae HQU highlights the continued spread of resistance determinants. It emphasizes the importance of surveillance programs and strict medication.%目的 对1株耐亚胺培南肺炎克雷伯菌(KPN)进行产金属β-内酰胺酶(MBLs)和产碳青霉烯酶(KPC)分析.方法 2010年4月2株KPN分别分离自天津市红桥医院1例住院患者的尿标本和痰标本,MIC法对分离菌株进行药物敏感试验,ESBLs确证试验检测其是否产ESBLs,PCR扩增blaIMP、blaVIM和KPC基因,扩增产物进行测序和分析.结果 2株KPN均为多药耐药菌,其中从尿中分离的KPN(HQU)对亚胺培南耐药,从痰中分离的KPN对亚胺培南敏感,均产ESBLs;从尿中分离的KPN携带MBLs基因blaIMP-4,且定位于质粒上;未检出blaVIM和KPC基因.结论产blaIMP-4型MBLs KPN的出现提示耐药性传播广泛,临床应加强耐药监测和严格药物使用.

  9. KPC-2-producing Klebsiella pneumoniae in a hospital in the Midwest region of Brazil

    Directory of Open Access Journals (Sweden)

    Camila Arguelo Biberg

    2015-06-01

    Full Text Available The emergence of β-lactamase-producing Enterobacteriaceae in the last few decades has become major challenge faced by hospitals. In this study, isolates of Klebsiella pneumoniae carbapenemase-2 (KPC-2-producing K. pneumoniae from a tertiary hospital in Mato Grosso do Sul, Brazil, were characterized. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF; Bruker Daltonics, Germany mass spectrometry. The minimum inhibitory concentrations of carbapenems were determined using the agar dilution method as recommended by the Clinical Laboratory Standards Institute guidelines. Carbapenemase production was detected using the modified Hodge test (MHT and polymerase chain reaction (PCR, followed by DNA sequencing. Of 360 (12.2% K. pneumoniae isolates obtained between May 2009 and May 2010, 44 (12.2% were carbapenem nonsusceptible. Of these 44 isolates, thirty-six K. pneumoniae isolates that were positive by MHT and PCR carried the blaKPC-2 gene. Thus, KPC-2producing Klebsiella pneumoniae has been present in a Brazilian hospital located in the Midwest region since at least 2009.

  10. KPC-2-producing Klebsiella pneumoniae in a hospital in the Midwest region of Brazil

    Science.gov (United States)

    Biberg, Camila Arguelo; Rodrigues, Ana Claudia Souza; do Carmo, Sidiane Ferreira; Chaves, Claudia Elizabeth Volpe; Gales, Ana Cristina; Chang, Marilene Rodrigues

    2015-01-01

    The emergence of β-lactamase-producing Enterobacteriaceae in the last few decades has become major challenge faced by hospitals. In this study, isolates of Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae from a tertiary hospital in Mato Grosso do Sul, Brazil, were characterized. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF; Bruker Daltonics, Germany) mass spectrometry. The minimum inhibitory concentrations of carbapenems were determined using the agar dilution method as recommended by the Clinical Laboratory Standards Institute guidelines. Carbapenemase production was detected using the modified Hodge test (MHT) and polymerase chain reaction (PCR), followed by DNA sequencing. Of 360 (12.2%) K. pneumoniae isolates obtained between May 2009 and May 2010, 44 (12.2%) were carbapenem nonsusceptible. Of these 44 isolates, thirty-six K. pneumoniae isolates that were positive by MHT and PCR carried the bla KPC-2 gene. Thus, KPC-2producing Klebsiella pneumoniae has been present in a Brazilian hospital located in the Midwest region since at least 2009. PMID:26273265

  11. KPC-2-producing Klebsiella pneumoniae in a hospital in the Midwest region of Brazil.

    Science.gov (United States)

    Biberg, Camila Arguelo; Rodrigues, Ana Claudia Souza; do Carmo, Sidiane Ferreira; Chaves, Claudia Elizabeth Volpe; Gales, Ana Cristina; Chang, Marilene Rodrigues

    2015-06-01

    The emergence of β-lactamase-producing Enterobacteriaceae in the last few decades has become major challenge faced by hospitals. In this study, isolates of Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae from a tertiary hospital in Mato Grosso do Sul, Brazil, were characterized. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF; Bruker Daltonics, Germany) mass spectrometry. The minimum inhibitory concentrations of carbapenems were determined using the agar dilution method as recommended by the Clinical Laboratory Standards Institute guidelines. Carbapenemase production was detected using the modified Hodge test (MHT) and polymerase chain reaction (PCR), followed by DNA sequencing. Of 360 (12.2%) K. pneumoniae isolates obtained between May 2009 and May 2010, 44 (12.2%) were carbapenem nonsusceptible. Of these 44 isolates, thirty-six K. pneumoniae isolates that were positive by MHT and PCR carried the bla KPC-2 gene. Thus, KPC-2producing Klebsiella pneumoniae has been present in a Brazilian hospital located in the Midwest region since at least 2009.

  12. Antimicrobial susceptibility and extended-spectrum beta-lactamase rates in aerobic gram-negative bacteria causing intra-abdominal infections in Vietnam: report from the Study for Monitoring Antimicrobial Resistance Trends (SMART 2009-2011).

    Science.gov (United States)

    Biedenbach, Douglas J; Bouchillon, Samuel K; Hoban, Daryl J; Hackel, Meredith; Phuong, Doan Mai; Nga, Tran Thi Thanh; Phuong, Nguyen Tran My; Phuong, Tran Thi Lan; Badal, Robert E

    2014-08-01

    Treatment options for multidrug-resistant pathogens remain problematic in many regions and individual countries, warranting ongoing surveillance and analysis. Limited antimicrobial susceptibility information is available for pathogens from Vietnam. This study determined the bacterial susceptibility of aerobic gram-negative pathogens of intra-abdominal infections among patients in Vietnam during 2009-2011. A total of 905 isolates were collected from 4 medical centers in this investigation as part of the Study for Monitoring Antimicrobial Resistance Trends. Antimicrobial susceptibility and extended-spectrum beta-lactamase (ESBL) rates among the appropriate species were determined by a central laboratory using Clinical and Laboratory Standards Institute methods. Among the species collected, Escherichia coli (48.1% ESBL-positive) and Klebsiella pneumoniae (39.5% ESBL-positive) represented the majority (46.4%) of the isolates submitted for this study. Ertapenem MIC90 values were lowest for these 2 species at 0.12 and 0.25μg/mL and remained unchanged for ESBL-positive isolates. Imipenem MIC90 values were also the same for all isolates and ESBL-positive strains at 0.25 and 0.5μg/mL, respectively. Ertapenem MIC90 values for additional species with sufficient numbers for analysis, including Enterobacter cloacae, Proteus mirabilis, Acinetobacter baumannii, and Pseudomonas aeruginosa, were 1, 0.06, >4, and >4μg/mL, respectively. Analysis of beta-lactamases in a subset of 132 phenotypically ESBL-positive Enterobacteriaceae demonstrated that CTX-M variants, particularly CTX-M-27 and CTX-M-15, were the predominant enzymes. High resistance rates in Vietnam hospitals dictate continuous monitoring as antimicrobial inactivating enzymes continue to spread throughout Asia and globally.

  13. New Delhi Metallo-beta-lactamase around the world: an eReview using Google Maps.

    Science.gov (United States)

    Berrazeg, M; Diene, Sm; Medjahed, L; Parola, P; Drissi, M; Raoult, D; Rolain, Jm

    2014-01-01

    Gram-negative carbapenem-resistant bacteria, in particular those producing New Delhi Metallo-betalactamase-1 (NDM-1), are a major global health problem. To inform the scientific and medical community in real time about worldwide dissemination of isolates of NDM-1-producing bacteria, we used the PubMed database to review all available publications from the first description in 2009 up to 31 December 2012, and created a regularly updated worldwide dissemination map using a web-based mapping application. We retrieved 33 reviews, and 136 case reports describing 950 isolates of NDM-1-producing bacteria. Klebsiella pneumoniae (n= 359) and Escherichia coli (n=268) were the most commonly reported bacteria producing NDM-1 enzyme. Several case reports of infections due to imported NDM-1 producing bacteria have been reported in a number of countries, including the United Kingdom, Italy, and Oman. In most cases (132/153, 86.3%), patients had connections with the Indian subcontinent or Balkan countries. Those infected were originally from these areas, had either spent time and/or been hospitalised there, or were potentially linked to other patients who had been hospitalised in these regions. By using Google Maps, we were able to trace spread of NDM-1-producing bacteria. We strongly encourage epidemiologists to use these types of interactive tools for surveillance purposes and use the information to prevent the spread and outbreaks of such bacteria.

  14. Spectroscopic Signature of a Ubiquitous Metal Binding Site in the Metallo-beta-lactamase Superfamily

    Energy Technology Data Exchange (ETDEWEB)

    V Campos-Bermudez; J Gonzalez; D Tierney; A Vila

    2011-12-31

    The metallo-{beta}-lactamase (M{beta}L) superfamily is a functionally diverse group of metalloproteins sharing a distinctive {alpha}{beta}/{alpha}{beta} fold and a characteristic metal binding motif. A large number of open reading frames identified in genomic sequencing efforts have been annotated as members of this superfamily through sequence comparisons. However, structural and functional studies performed on purified proteins are normally needed to unequivocally include a newly discovered protein in the M{beta}L superfamily. Here we report the spectroscopic characterization of recombinant YcbL, a gene product annotated as a member of the M{beta}L superfamily whose function in vivo remains unknown. By taking advantage of the structural features characterizing the M{beta}L superfamily metal binding motif, we performed spectroscopic studies on Zn(II)- and Co(II)-substituted YcbL to structurally interrogate the metal binding site. The dinuclear center in Co(II)-YcbL was shown to display characteristic electronic absorption features in the visible region, which were also observed in an engineered M{beta}L aimed at mimicking this metal site. Thus, the spectroscopic features reported herein can be employed as a signature to readily identify and characterize the presence of these ubiquitous metal binding sites.

  15. Covalent docking of selected boron-based serine beta-lactamase inhibitors

    Science.gov (United States)

    Sgrignani, Jacopo; Novati, Beatrice; Colombo, Giorgio; Grazioso, Giovanni

    2015-05-01

    AmpC β-lactamase is a hydrolytic enzyme conferring resistance to β-lactam antibiotics in multiple Gram-negative bacteria. Therefore, identification of non-β-lactam compounds able to inhibit the enzyme is crucial for the development of novel antibacterial therapies. In general, AmpC inhibitors have to engage the highly solvent-exposed catalytic site of the enzyme. Therefore, understanding the implications of ligand-protein induced-fit and water-mediated interactions behind the inhibitor-enzyme recognition process is fundamental for undertaking structure-based drug design process. Here, we focus on boronic acids, a promising class of beta-lactamase covalent inhibitors. First, we optimized a docking protocol able to reproduce the experimentally determined binding mode of AmpC inhibitors bearing a boronic group. This goal was pursued (1) performing rigid and flexible docking calculations aiming to establish the role of the side chain conformations; and (2) investigating the role of specific water molecules in shaping the enzyme active site and mediating ligand protein interactions. Our calculations showed that some water molecules, conserved in the majority of the considered X-ray structures, are needed to correctly predict the binding pose of known covalent AmpC inhibitors. On this basis, we formalized our findings in a docking and scoring protocol that could be useful for the structure-based design of new boronic acid AmpC inhibitors.

  16. Engineering allosteric regulation into the hinge region of a circularly permuted TEM-1 beta-lactamase.

    Science.gov (United States)

    Mathieu, Valéry; Fastrez, Jacques; Soumillion, Patrice

    2010-09-01

    In nature, the activity of many enzymes involved in important biochemical pathways is controlled by binding a ligand in a site remote from the active site. The allosteric sites are frequently located in hinge regulatory subunits, in which a conformational change can occur and propagate to the active site. The enzymatic activity is then enhanced or decreased depending on the type of effectors. Many artificial binding sites have been created to engineer an allosteric regulation. Generally, these sites were engineered near the active site in loops or at the surface of contiguous helices or strands but rarely in hinge regions. This work aims at exploring the possibility of regulating a monomeric enzyme whose active site is located at the interface between two domains. We anticipated that binding of a ligand in the hinge region linking the domains would modify their positioning and, consequently, modulate the activity. Here, we describe the design of two mutants in a circularly permuted TEM-1 (cpTEM-1) beta-lactamase. The first one, cpTEM-1-His(3) was created by a rational design. It shows little regulation upon metal ion binding except for a weak activation with Zn(2+). The second one, cpTEM-1-3M-His(2), was selected by a directed evolution strategy. It is allosterically down-regulated by Zn(2+), Ni(2+) and Co(2+) with binding affinities around 300 microM.

  17. Plasmid-mediated quinolone resistance among extended spectrum beta lactase producing Enterobacteriaceae from bloodstream infections.

    Science.gov (United States)

    Domokos, Judit; Kristóf, Katalin; Szabó, Dóra

    2016-09-01

    The purpose of this study was to determine prevalence and molecular characterization of plasmid-mediated quinolone resistance (PMQR) genes [qnrA, qnrB, qnrC, qnrD, qnrS, aac(6')-Ib-cr, qepA, and oqxAB] among extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella spp. isolates from bloodcultures in Hungary. A total of 103 isolates were tested for quinolone susceptibility by microdilution method and PMQR genes were detected by polymerase chain reaction. About 40 ESBL-producing E. coli (39%) and 50 ESBL-producing Klebsiella spp. strains (48%) were resistant to ciprofloxacin; 40 ESBL-producing E. coli (39%) and 47 ESBL-producing Klebsiella spp. strains (45%) were resistant to levofloxacin; and 88 strains including 40 ESBL-producing E. coli (39%) and 48 (47%) ESBL-producing Klebsiella spp. were resistant to moxifloxacin. Among the 103 ESBL-producing isolates, 77 (75%) isolates (30 E. coli and 47 Klebsiella spp.) harbored PMQR genes. The most commonly detected gene was aac(6')-Ib-cr (65%). The occurrence of qnrS gene was 6%. Interestingly, qnrA, qnrB, qnrC, qnrD, and qepA were not found in any isolates. Among 77 PMQR-positive isolates, 27 (35.1%) and 1 (1.3%) carried two and three different PMQR genes, respectively. Only Klebsiella spp. harbored more than one PMQR genes. Observing prevalence of PMQR genes in the last 8 years, the increasing incidence of aac(6')-Ib-cr and oqxAB can be seen. Our results highlight high frequency of PMQR genes among ESBL-producing Klebsiella pneumoniae and E. coli isolates with an increasing dynamics in Hungary.

  18. Acquired resistance of Nocardia brasiliensis to clavulanic acid related to a change in beta-lactamase following therapy with amoxicillin-clavulanic acid.

    Science.gov (United States)

    Steingrube, V A; Wallace, R J; Brown, B A; Pang, Y; Zeluff, B; Steele, L C; Zhang, Y

    1991-01-01

    Previous studies have demonstrated that Nocardia brasiliensis is susceptible to amoxicillin-clavulanic acid and that its beta-lactamases are inhibited in vitro by clavulanic acid. A cardiac transplant patient with disseminated infection caused by N. brasiliensis was treated with this drug combination with good response, but relapsed while still on therapy. The relapse isolate was found to be identical to the initial isolate by using genomic DNA restriction fragment patterns obtained by pulsed field gel electrophoresis, but it was resistant to amoxicillin-clavulanic acid. On isoelectric focusing, the beta-lactamase from the relapse isolate exhibited a shift in the isoelectric point (pI) of its major band from 5.10 to 5.04 compared with the enzyme from the pretreatment isolate. As determined by using values of the amount of beta-lactamase inhibitor necessary to give 50 +/- 5% inhibition of beta-lactamase-mediated hydrolysis of 50 microM nitrocefin, the beta-lactamase of the relapse isolate was also 200-fold more resistant than the enzyme from the pretreatment isolate to clavulanic acid and was more resistant to sulbactam, tazobactam, cloxacillin, and imipenem. The beta-lactamase of the relapse isolate exhibited a 10-fold decrease in hydrolytic activity for cephaloridine and other hydrolyzable cephalosporins compared with that for nitrocefin. Acquired resistance to amoxicillin-clavulanic acid in this isolate of N. brasiliensis appears to have resulted from a mutational change affecting the inhibitor and active site(s) in the beta-lactamase. Images PMID:2039203

  19. Development of a multiplex real-time PCR for the rapid detection of the predominant beta-lactamase genes CTX-M, SHV, TEM and CIT-type AmpCs in Enterobacteriaceae.

    Directory of Open Access Journals (Sweden)

    Nicole Roschanski

    Full Text Available Beta-lactamase resistant bacteria and especially ESBL producing Enterobacteriaceae are an increasing problem worldwide. For this reason a major interest in efficient and reliable methods for rapid screening of high sample numbers is recognizable. Therefore, a multiplex real-time PCR was developed to detect the predominant class A beta-lactamase genes blaCTX-M, blaSHV, blaTEM and CIT-type AmpCs in a one-step reaction. A set of 114 Enterobacteriaceae containing previously identified resistance gene subtypes and in addition 20 undefined animal and environmental isolates were used for the validation of this assay. To confirm the accessibility in variable settings, the real-time runs were performed analogous in two different laboratories using different real-time cyclers. The obtained results showed complete accordance between the real-time data and the predetermined genotypes. Even if sequence analyses are further necessary for a comprehensive characterization, this method was proofed to be reliable for rapid screening of high sample numbers and therefore could be an important tool for e. g. epidemiological purposes or support infection control measures.

  20. Contaminated Handwashing Sinks as the Source of a Clonal Outbreak of KPC-2-Producing Klebsiella oxytoca on a Hematology Ward

    Science.gov (United States)

    Leitner, Eva; Zarfel, Gernot; Luxner, Josefa; Herzog, Kathrin; Pekard-Amenitsch, Shiva; Hoenigl, Martin; Valentin, Thomas; Feierl, Gebhard; Grisold, Andrea J.; Högenauer, Christoph; Sill, Heinz; Krause, Robert

    2014-01-01

    We investigated sinks as possible sources of a prolonged Klebsiella pneumonia carbapenemase (KPC)-producing Klebsiella oxytoca outbreak. Seven carbapenem-resistant K. oxytoca isolates were identified in sink drains in 4 patient rooms and in the medication room. Investigations for resistance genes and genetic relatedness of patient and environmental isolates revealed that all the isolates harbored the blaKPC-2 and blaTEM-1 genes and were genetically indistinguishable. We describe here a clonal outbreak caused by KPC-2-producing K. oxytoca, and handwashing sinks were a possible reservoir. PMID:25348541

  1. Whole-genome multilocus sequence typing of extended-spectrum-beta-lactamase-producing enterobacteriaceae

    NARCIS (Netherlands)

    Kluytmans-Van Den Bergh, Marjolein F Q; Rossen, John W A; Bruijning-Verhagen, Patricia C J; Bonten, Marc J M; Friedrich, Alexander W.; Vandenbroucke-Grauls, Christina M J E; Willems, Rob J L; Kluytmans, Jan A.J.W.

    2016-01-01

    Molecular typing has become indispensable in the detection of nosocomial transmission of bacterial pathogens and the identification of sources and routes of transmission in outbreak settings, but current methods are labor-intensive, are difficult to standardize, or have limited resolution. Whole-gen

  2. Whole-Genome Multilocus Sequence Typing of Extended-Spectrum-Beta-Lactamase-Producing Enterobacteriaceae

    NARCIS (Netherlands)

    Kluytmans-van den Bergh, Marjolein F. Q.; Rossen, John W. A.; Bruijning-Verhagen, Patricia C. J.; Bonten, Marc J. M.; Friedrich, Alexander W.; Vandenbroucke-Grauls, Christina M. J. E.; Willems, Rob J. L.; Kluytmans, Jan A. J. W.

    2016-01-01

    Molecular typing has become indispensable in the detection of nosocomial transmission of bacterial pathogens and the identification of sources and routes of transmission in outbreak settings, but current methods are labor-intensive, are difficult to standardize, or have limited resolution. Whole-gen

  3. Audouin's gull, a potential vehicle of an extended spectrum beta-lactamase producing Salmonella Agona

    DEFF Research Database (Denmark)

    Antilles, Noelia; Garcia-Migura, Lourdes; Joensen, Katrine Grimstrup;

    2015-01-01

    The genome of a multidrug-resistant Salmonella Agona isolated from Larus audouinii (Audouin's gull) in Spain was examined. The isolate showed high levels of resistance to different antimicrobials, including third generation cephalosporins and fluoroquinolones, which is a public health concern...

  4. Extended Spectrum Beta Lactamase producing Cephalosporin resistant Salmonella Typhi, reported from Rawalpindi, Pakistan.

    Science.gov (United States)

    Munir, Tehmina; Lodhi, Munir; Ansari, Jawad Khaliq; Andleeb, Saadia; Ahmed, Mushtaq

    2016-08-01

    Typhoid is endemic in many parts of southeast Asia. Due to the resistance of the organism to first line of antibiotics (ampicillin, chloramphenicol, cotrimoxazole) as well as to fluoroquinolones, third generation cephalosporins have been in use for the empiric treatment of typhoid for years. However an increasing incidence of Salmonella Typhi is being reported sporadically from various regions. We report a case of typhoid due to Salmonella Typhi which was non-responsive to treatment with a cephalosporin, was found to be multidrug resistant and resistant to ciprofloxacin and third generation cephalosporin as well. The patient was finally treated successfully with intravenous administration of a carbapenem.

  5. Carriage of beta-lactamase-producing Enterobacteriaceae among nursing home residents in north Lebanon

    Directory of Open Access Journals (Sweden)

    Iman Dandachi

    2016-04-01

    Conclusions: The high prevalence of MDR Enterobacteriaceae detected in this study and the emergence of carbapenem resistance is alarming. Efficient infection control measures and antibiotic stewardship programs are urgently needed in these settings in order to limit the spread of resistant strains.

  6. Emergence of VIM-2 metallo-beta-lactamase producing Ralstonia pickettii clinical isolate in India

    Directory of Open Access Journals (Sweden)

    A Khajuria

    2014-01-01

    Full Text Available A multidrug-resistant clinical isolate of Ralstonia pickettii from a woman was analysed. Modified Hodge test was positive for carbapenemase production. Conjugation experiment revealed the presence of conjugative plasmid of >140 Kb size typed as IncN type. This is the first report of emergence blaVIM-2 in R. pickettii in India.

  7. Diversity of genotypes in CTX-M-producing Klebsiella pneumoniae isolated in different hospitals in Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Pavoni Gomes Chagas

    2011-10-01

    Full Text Available OBJECTIVE: The present study was undertaken to characterize CTX-M ESBL-producing Klebsiella pneumoniae collected from hospitals in different cities of Brazil. MATERIAL AND METHODS: Eighty-five K. pneumoniae strains isolated from hospitalized patients in six different hospitals of three cities of Brazil were analyzed. ESBL production was confirmed by the standard double-disk synergy test and the Etest®. The MIC50 and MIC90 for ESBL-producing isolates were determined by the Etest® method. The antimicrobial susceptibilities of bacterial isolates were determined using the agar diffusion method according to the CLSI. Screening for blaTEM, blaSHV, blaCTX-M genes and class 1 integron was performed by PCR amplification. To determine the genomic diversity of CTX-M-producers, isolates were analyzed by macrorestriction profile analysis following PFGE. RESULTS AND DISCUSSION: Seventy-one K. pneumoniae isolates were ESBL-producing. PCR and sequencing experiments detected 38 CTX-M-producing K. pneumoniae belonged to groups CTX-M 1, CTX-M 2, CTX-M 8 and CTX-M 9. The association of different types ESBL (CTX-M, SHV and TEM was frequent. All K. pneumoniae isolates carried class 1 integron. PFGE analysis revealed thirty-one clonal types among CTX-M-producing isolates. The data presented herein illustrate the diversity of genotypes of CTX-M producing K. pneumoniae among Brazilians hospitals.

  8. Rapid Induction of High-Level Carbapenem Resistance in Heteroresistant KPC-Producing Klebsiella pneumoniae

    Science.gov (United States)

    Adams-Sapper, Sheila; Nolen, Shantell; Donzelli, Grace Fox; Lal, Mallika; Chen, Kunihiko; Justo da Silva, Livia Helena; Moreira, Beatriz M.

    2015-01-01

    Enterobacteriaceae strains producing the Klebsiella pneumoniae carbapenemase (KPC) have disseminated worldwide, causing an urgent threat to public health. KPC-producing strains often exhibit low-level carbapenem resistance, which may be missed by automated clinical detection systems. In this study, eight Klebsiella pneumoniae strains with heterogeneous resistance to imipenem were used to elucidate the factors leading from imipenem susceptibility to high-level resistance as defined by clinical laboratory testing standards. Time-kill analysis with an inoculum as low as 3 × 106 CFU/ml and concentrations of imipenem 8- and 16-fold higher than the MIC resulted in the initial killing of 99.9% of the population. However, full recovery of the population occurred by 20 h of incubation in the same drug concentrations. Population profiles showed that recovery was mediated by a heteroresistant subpopulation at a frequency of 2 × 10−7 to 3 × 10−6. Samples selected 2 h after exposure to imipenem were as susceptible as the unexposed parental strain and produced the major outer membrane porin OmpK36. However, between 4 to 8 h after exposure, OmpK36 became absent, and the imipenem MIC increased at least 32-fold. Individual colonies isolated from cultures after 20 h of exposure revealed both susceptible and resistant subpopulations. Once induced, however, the high-level imipenem resistance was maintained, and OmpK36 remained unexpressed even without continued carbapenem exposure. This study demonstrates the essential coordination between blaKPC and ompK36 expression mediating high-level imipenem resistance from a population of bacteria that initially exhibits a carbapenem-susceptibility phenotype. PMID:25801565

  9. Emergence of carbapenemase-producing Klebsiella pneumoniae of sequence type 258 in Michigan, USA

    Directory of Open Access Journals (Sweden)

    Ruchika Jain

    2013-03-01

    Full Text Available The prevalence of carbapenemase-producing Enterobacteriaceae (CPE in our hospital increased beginning in 2009. We aimed to study the clinical and molecular epidemiology of these emerging isolates. We performed a retrospective review of all adult patients with clinical cultures confirmed as CPE by positive modified Hodge test from 5/2009-5/2010 at the University of Michigan Health System (UMHS. Clinical information was obtained from electronic medical records. Available CPE isolates were analyzed by polymerase chain reaction (PCR and sequencing of the 16S rRNA encoding gene and blaKPC locus. Multilocus sequence typing (MLST was used to characterize Klebsiella pneumoniae isolates. Twenty six unique CPE isolates were obtained from 25 adult patients. The majority were Klebsiella pneumoniae (n=17. Other isolates included K. oxytoca (n=3, Citrobacter freundii (n=2, Enterobacter cloacae (n=2, Enterobacter aerogenes (n=1 and Escherichia coli (n=1. Molecular characterization of 19 available CPE isolates showed that 13 (68% carried the KPC-3 allele and 6 (32% carried the KPC-2 allele. Among 14 available K. pneumoniae strains, 12 (86% carried the KPC-3 allele and belonged to a common lineage, sequence type (ST 258. The other 2 (14% K. pneumoniae isolates carried the KPC-2 allele and belonged to two unique STs. Among these ST 258 strains, 67% were isolated from patients with prior exposures to health care settings outside of our institution. In contrast, all CPE isolates carrying the KPC-2 allele and all non ST 258 CPE isolates had acquisition attributable to our hospital. Molecular epidemiology of carbapenemase producing K. pneumoniae suggests that KPC-3 producing K. pneumoniae isolates of a common lineage, sequence type (ST 258, are emerging in our hospital. While ST 258 is a dominant sequence type throughout the United States, this study is the first to report its presence in Michigan.

  10. Effect of a Metalloantibiotic Produced by Pseudomonas aeruginosa on Klebsiella pneumoniae Carbapenemase (KPC)-producing K. pneumoniae.

    Science.gov (United States)

    Kerbauy, Gilselena; Vivan, Ana C P; Simões, Glenda C; Simionato, Ane S; Pelisson, Marsileni; Vespero, Eliana C; Costa, Silvia F; Andrade, Celia G T de J; Barbieri, Daiane M; Mello, João C P; Morey, Alexandre T; Yamauchi, Lucy M; Yamada-Ogatta, Sueli F; de Oliveira, Admilton G; Andrade, Galdino

    2016-01-01

    Multidrug-resistant organisms (MDRO) are a great problem in hospitals, where thousands of people are infected daily, with the occurrence of high mortality rates, especially in infections caused by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-producing Kpn). The challenge is to find new compounds that can control KPC producing-Kpn infections. The aim of this study was to evaluate the antibiotic activity of the F3d fraction produced by the Pseudomonas aeruginosa LV strain against clinical isolates of KPC-producing Kpn. The results showed that the minimum inhibitory concentration of F3d (62.5 µg mL(-1)), containing an organic metallic compound, killed planktonic cells of KPC-producing Kpn strains after 30 min of incubation. At the same concentration, this fraction also showed an inhibitory effect against biofilm of these bacteria after 24 h of incubation. Treatment with the F3d fraction caused pronounced morphological alterations in both planktonic and biofilm cells of the bacteria. The inhibitory effect of the F3d fraction seems to be more selective for the bacteria than the host cells, indicating its potential in the development of new drugs for the treatment of infections caused by KPC-producing Kpn and other MDRO.

  11. Imaging tuberculosis with endogenous beta-lactamase reporter enzyme fluorescence in live mice.

    Science.gov (United States)

    Kong, Ying; Yao, Hequan; Ren, Hongjun; Subbian, Selvakumar; Cirillo, Suat L G; Sacchettini, James C; Rao, Jianghong; Cirillo, Jeffrey D

    2010-07-06

    The slow growth rate and genetic intractability of tubercle bacilli has hindered progress toward understanding tuberculosis, one of the most frequent causes of death worldwide. We overcame this roadblock through development of near-infrared (NIR) fluorogenic substrates for beta-lactamase, an enzyme expressed by tubercle bacilli, but not by their eukaryotic hosts, to allow real-time imaging of pulmonary infections and rapid quantification of bacteria in living animals by a strategy called reporter enzyme fluorescence (REF). This strategy has a detection limit of 6 +/- 2 x 10(2) colony-forming units (CFU) of bacteria with the NIR substrate CNIR5 in only 24 h of incubation in vitro, and as few as 10(4) CFU in the lungs of live mice. REF can also be used to differentiate infected from uninfected macrophages by using confocal microscopy and fluorescence activated cell sorting. Mycobacterium tuberculosis and the bacillus Calmette-Guérin can be tracked directly in the lungs of living mice without sacrificing the animals. Therapeutic efficacy can also be evaluated through loss of REF signal within 24 h posttreatment by using in vitro whole-bacteria assays directly in living mice. We expect that rapid quantification of bacteria within tissues of a living host and in the laboratory is potentially transformative for tuberculosis virulence studies, evaluation of therapeutics, and efficacy of vaccine candidates. This is a unique use of an endogenous bacterial enzyme probe to detect and image tubercle bacilli that demonstrates REF is likely to be useful for the study of many bacterial infections.

  12. Multicentre investigation of carbapenemase-producing Escherichia coli and Klebsiella pneumoniae in German hospitals.

    Science.gov (United States)

    Kaase, Martin; Schimanski, Sven; Schiller, Reinhold; Beyreiß, Bettina; Thürmer, Alexander; Steinmann, Jörg; Kempf, Volkhard A; Hess, Christina; Sobottka, Ingo; Fenner, Ines; Ziesing, Stefan; Burckhardt, Irene; von Müller, Lutz; Hamprecht, Axel; Tammer, Ina; Wantia, Nina; Becker, Karsten; Holzmann, Thomas; Furitsch, Martina; Volmer, Gabriele; Gatermann, Sören G

    2016-09-01

    Aim of this study was to determine the incidence and molecular epidemiology of carbapenemase-producing Escherichia coli and Klebsiella pneumoniae in Germany. E. coli and K. pneumoniae isolates from clinical samples which were non-susceptible to carbapenems were collected in laboratories serving 20 hospitals throughout Germany from November 2013 to April 2014. The isolates were tested for the presence of carbapenemases by PCR and phenotypic methods and typed by multilocus sequence typing. Risk factors including a previous hospitalization abroad were analysed. Carbapenemases were detected in 24 isolates from 22 patients out of 464,514 admissions. Carbapenemases included OXA-48 (n=14), KPC-2 (n=8) and NDM-1 (n=2). Except for two K. pneumoniae isolates with ST101, all OXA-48 producing strains belonged to different clones. In contrast, half of KPC-2 producing K. pneumoniae were of ST258 and both NDM-1 producing strains were of ST11. Compared to carbapenem-susceptible controls, patients with carbapenemase-producing strains differed by a significantly higher proportion of males, a higher proportion of isolates from wound samples and a more frequent previous stay abroad in univariate analysis. This multicentre study demonstrated an incidence of carbapenemase-producing E. coli and K. pneumoniae from clinical samples in Germany of 0.047 cases per 1000 admissions. OXA-48 was more frequent than KPC-2 and NDM-1 and showed a multiclonal background.

  13. First Report of KPC-2 Carbapenemase-Producing Klebsiella pneumoniae in Japan

    Science.gov (United States)

    Takahashi, Rieko; Sawabe, Etsuko; Koyano, Saho; Takahashi, Yutaka; Shima, Mari; Ushizawa, Hiroto; Fujie, Toshihide; Tosaka, Naoki; Kato, Yuko; Moriya, Kyoji; Tohda, Shuji; Tojo, Naoko; Koike, Ryuji; Kubota, Tetsuo

    2014-01-01

    We investigated a novel Japanese isolate of sequence type 11 (ST11), the Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae strain Kp3018, which was previously obtained from a patient treated at a Brazilian hospital. This strain was resistant to various antibiotic classes, including carbapenems, and harbored the gene blaKPC-2, which was present on the transferable plasmid of ca. 190 kb, in addition to the blaCTX-M-15 gene. Furthermore, the ca. 2.3-kb sequences (ISKpn8-blaKPC-2–ISKpn6-like), encompassing blaKPC-2, were found to be similar to those of K. pneumoniae strains from China. PMID:24566171

  14. Detection of metallo β-lactamase producing Klebsiella pneumoniae in a neonatal septicemia

    Institute of Scientific and Technical Information of China (English)

    Debasmita Dubey; Rachita Sarangi; Nagen K Debata; Rabindra N Padhy

    2013-01-01

    A 10-day old preterm neonate, appropriate for the date, was admitted for lethargy and feeding intolerance. By culturing its blood, the antibiogram of the causative bacterium was ascertained by both Kirby-Bauer disc diffusion method and the Vitek2 system. Due clinical steps were taken for survival of the baby. The baby was suffering from septicemia. The causative bacterium was Klebsiella pneumoniae (K. pneumoniae). The isolated strain was found resistant to a total of 17 antibiotics; the strain was positive for extended spectrum β-lactamase production and resistant to two carbapenems, imipenem and meropenem. The baby could not survive. The baby was infected with an appalling strain of K. pneumoniae with a capacity to produce metalloβ-lactamase overriding carbapenems, which is found to present in the state of Odisha, India.

  15. Molecular Characterization of Klebsiella pneumoniae Carbapenemase (KPC)-Producing Enterobacteriaceae in Ontario, Canada, 2008-2011

    Science.gov (United States)

    Tijet, Nathalie; Sheth, Prameet M.; Lastovetska, Olga; Chung, Catherine; Patel, Samir N.; Melano, Roberto G.

    2014-01-01

    Due to the lack of detailed reports of Klebsiella pneumoniae carbapenemase (KPC)-producing enterobacteria in Ontario, Canada, we perform a molecular characterization of KPC-producing Enterobacteriaceae submitted to the provincial reference laboratory from 2008 to 2011. Susceptibility profiles were accessed by E-test. Molecular types of isolates were determined by pulse-field gel electrophoresis (PFGE) and multilocus sequence typing. Screening of ß-lactamase genes was performed by multiplex PCR and alleles were identified by DNA sequencing. The genetic platform of blaKPC gene was analyzed by PCR. Plasmid replicons were typed using PCR-based typing approach. KPC-plasmids were also evaluated by S1 nuclease-PFGE and Southern blot. Thirty unique clinical isolates (26 Klebsiella pneumoniae, 2 Enterobacter cloacae, 1 Citrobacter freundii and 1 Raoultella ornithinolytica) were identified as blaKPC positive: 4 in 2008, 3 in 2009, 10 in 2010 and 13 in 2011. The majority exhibited resistance to carbapenems, cephalosporins and fluoroquinolones and two isolates were also resistant to colistin. The isolates harbored blaKPC-2 (n = 23) or blaKPC-3 (n = 7). blaTEM-1 (n = 27) was commonly detected and occasionally blaOXA-1 (n = 3) and blaCTX-M-15 (n = 1). As expected, all K. pneumoniae isolates carried blaSHV-11. blaKPC genes were identified on Tn4401a (n = 20) or b (n = 10) isoforms, on plasmids of different sizes belonging to the incompatibility groups IncFIIA (n = 19), IncN (n = 3), IncI2 (n = 3), IncFrep (n = 2) and IncA/C (n = 1). The occurrence of KPC ß-lactamase in Ontario was mainly associated with the spread of the K. pneumoniae clone ST258. PMID:25549365

  16. Molecular characterization of Klebsiella pneumoniae carbapenemase (KPC-producing Enterobacteriaceae in Ontario, Canada, 2008-2011.

    Directory of Open Access Journals (Sweden)

    Nathalie Tijet

    Full Text Available Due to the lack of detailed reports of Klebsiella pneumoniae carbapenemase (KPC-producing enterobacteria in Ontario, Canada, we perform a molecular characterization of KPC-producing Enterobacteriaceae submitted to the provincial reference laboratory from 2008 to 2011. Susceptibility profiles were accessed by E-test. Molecular types of isolates were determined by pulse-field gel electrophoresis (PFGE and multilocus sequence typing. Screening of ß-lactamase genes was performed by multiplex PCR and alleles were identified by DNA sequencing. The genetic platform of blaKPC gene was analyzed by PCR. Plasmid replicons were typed using PCR-based typing approach. KPC-plasmids were also evaluated by S1 nuclease-PFGE and Southern blot. Thirty unique clinical isolates (26 Klebsiella pneumoniae, 2 Enterobacter cloacae, 1 Citrobacter freundii and 1 Raoultella ornithinolytica were identified as blaKPC positive: 4 in 2008, 3 in 2009, 10 in 2010 and 13 in 2011. The majority exhibited resistance to carbapenems, cephalosporins and fluoroquinolones and two isolates were also resistant to colistin. The isolates harbored blaKPC-2 (n = 23 or blaKPC-3 (n = 7. blaTEM-1 (n = 27 was commonly detected and occasionally blaOXA-1 (n = 3 and blaCTX-M-15 (n = 1. As expected, all K. pneumoniae isolates carried blaSHV-11. blaKPC genes were identified on Tn4401a (n = 20 or b (n = 10 isoforms, on plasmids of different sizes belonging to the incompatibility groups IncFIIA (n = 19, IncN (n = 3, IncI2 (n = 3, IncFrep (n = 2 and IncA/C (n = 1. The occurrence of KPC ß-lactamase in Ontario was mainly associated with the spread of the K. pneumoniae clone ST258.

  17. Emergence of Multi-drug Resistant ESBL Producing Strains among Enterobacteriaceae Members Isolated from Patients Blood Samples in South of Iran.

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    Jalal Mardaneh

    2015-11-01

    Full Text Available Background: Extended-spectrum beta-lactamases (ESBLs have emerged as important mechanism of resistance among enterobacteriaceae family. These ESBL positive strains are major problem in hospitalized patients. The goal of this study was the survey emergence of multi-drug resistant ESBL producing strains among enterobacteriaceae members isolated from patients blood samples using BACTEC 9240 automatic system in south of Iran. Materials & Methods: In this cross-sectional study, 4825 blood samples were collected from hospitalized patients, and positive samples were detected by BACTEC automatic system. Positive blood cultures removed from BACTEC and subculture was performed on microbiological media including blood agar, chocolate agar and MacConkey agar. The isolates were identified based on biochemical tests embedded in the API-20E system. Susceptibility testing (disc diffusion was performed according clinical and laboratory standards institute (CLSI, 2013 guidelines. Phenotypic detection of extended spectrum beta-lactamase producing isolates was performed by double disk synergy test (DDST. Results: Total 1145 (24% blood cultures were positive that among them 248 (21.5% belonged to the enterobacteriaceae family. The most common isolates in this family were Escherichia coli (46.5%, Klebsiella spp. (28%, Enterobacter spp. (13.5%. Among enterobacteriaceae family, ampicillin was most effective drug against Salmonella isolates. Escherichia coli was the most common ESBL-producing isolate (58% of isolates were ESBL positive. Respectively, polymyxin B, colistin, imipenem were the most effective drugs against ESBL-positive Klebsiella strains. The ESBL-positive Enterobacter strains showed lowest resistance to imipenem (7.7%. All ESBL positive Serratia isolates were sensitive to chloramphenicol, co-trimoxazole and imipenem. Conclusion: Results showed unfortunately betalactam antibiotics are not effective against more than 40% of bacteremia caused by Escherichia

  18. Duration of Colonization With Klebsiella pneumoniae Carbapenemase-Producing Bacteria at Long-Term Acute Care Hospitals in Chicago, Illinois

    NARCIS (Netherlands)

    Haverkate, Manon R; Weiner, Shayna; Lolans, Karen; Moore, Nicholas M; Weinstein, Robert A; Bonten, Marc J M; Hayden, Mary K; Bootsma, Martin C J

    2016-01-01

    Background.  High prevalence of Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae has been reported in long-term acute care hospitals (LTACHs), in part because of frequent readmissions of colonized patients. Knowledge of the duration of colonization with KPC is essential to iden

  19. Molecular characterization of DHA-1-producing Klebsiella pneumoniae isolates collected during a 4-year period in an intensive care unit.

    Science.gov (United States)

    Compain, Fabrice; Decré, Dominique; Fulgencio, Jean-Pierre; Berraho, Sfia; Arlet, Guillaume; Verdet, Charlotte

    2014-10-01

    Seventeen Klebsiella pneumoniae isolates producing DHA-1 β-lactamase were collected in an intensive care unit between 2006 and 2010. Molecular analysis revealed the predominance of ST48 and ST1263 clones of K. pneumoniae and the spread of DHA-1-encoding plasmids belonging to incompatibility group IncL/M or IncHI2.

  20. Emergence of Klebsiella pneumoniae clinical isolates producing KPC-2 carbapenemase in Cuba

    Science.gov (United States)

    Quiñones, D; Hart, M; Espinosa, F; Garcia, S; Carmona, Y; Ghosh, S; Urushibara, N; Kawaguchiya, M; Kobayashi, N

    2014-01-01

    The emergence of Klebsiella pneumoniae producing carbapenemase (KPC) has now become a global concern. As a part of a nationwide multicentre surveillance study in Cuba, three K. pneumoniae clinical isolates resistant to carbapenems were detected for a 1-month period (September to October 2011). PCR and sequence analysis revealed that the three strains harboured blaKPC-2. They showed resistance or intermediate susceptibility to expanded-spectrum cephalosporins, other β-lactams, a β-lactam/β-lactamase inhibitor combination, and gentamicin. Two strains were susceptible only to colistin, whereas the other strain showing colistin resistance was susceptible to fluoroquinolones. These blaKPC-2-positive K. pneumoniae strains were classified into ST1271 (CC29), a novel clone harbouring blaKPC-2, and were revealed to be genetically identical by PCR-based DNA fingerprinting. The three patients infected with the KPC-producing K. pneumoniae had common risk factors, and had no overseas travel experience outside Cuba, suggesting local acquisition of the resistant pathogen. This is the first report of a KPC-producing K. pneumoniae in Cuba. Although detection of KPC in Enterobacteriaceae is still rare in Cuba, our finding indicated that KPC-producing bacteria are a global concern and highlighted the need to identify these microorganisms in clinical laboratories. PMID:25356357

  1. Emergence of Klebsiella pneumoniae clinical isolates producing KPC-2 carbapenemase in Cuba

    Directory of Open Access Journals (Sweden)

    D. Quinones

    2014-07-01

    Full Text Available The emergence of Klebsiella pneumoniae producing carbapenemase (KPC has now become a global concern. As a part of a nationwide multicentre surveillance study in Cuba, three K. pneumoniae clinical isolates resistant to carbapenems were detected for a 1-month period (September to October 2011. PCR and sequence analysis revealed that the three strains harboured blaKPC-2. They showed resistance or intermediate susceptibility to expanded-spectrum cephalosporins, other ß-lactams, a ß-lactam/ß-lactamase inhibitor combination, and gentamicin. Two strains were susceptible only to colistin, whereas the other strain showing colistin resistance was susceptible to fluoroquinolones. These blaKPC-2-positive K. pneumoniae strains were classified into ST1271 (CC29, a novel clone harbouring blaKPC-2, and were revealed to be genetically identical by PCR-based DNA fingerprinting. The three patients infected with the KPC-producing K. pneumoniae had common risk factors, and had no overseas travel experience outside Cuba, suggesting local acquisition of the resistant pathogen. This is the first report of a KPC-producing K. pneumoniae in Cuba. Although detection of KPC in Enterobacteriaceae is still rare in Cuba, our finding indicated that KPC-producing bacteria are a global concern and highlighted the need to identify these microorganisms in clinical laboratories.

  2. Nosocomial emerging of (VIM1 carbapenemase-producing isolates of Klebsiella pneumoniae in North of Iran

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    Ramazan Rajabnia

    2015-10-01

    Full Text Available Background and Objectives: The rapid emergence and dissemination of carbapenemase-producing Klebsiella pneumoniae strains and other members of the Enterobacteriaceae poses a considerable threat to the care of hospitalized patients and to public health. The aim of this study was to determine the frequency of metallo-β-lactamases (MBL and VIM-1 gene inmultidrug-resistant strains of K. pneumoniae.Methods: 50 isolates of non – duplicated K. pneumoniae cultured from patients at intensive care units were tested for their susceptibilities to 13 different antibiotics using microbroth dilution assay. Isolates showing resistance to at least one of the carbapenems were checked for production of metallo-β-lactamase (MBLs using imipenem–EDTA synergy tests. PCR was used to detect the gene encoding VIM-1 metallo-β-lactamase (MBL.Results: Of 50 clinical isolates, 26 (52% were resistant to imipenem in disk diffusion method. Using imipenem–EDTA synergy tests, production of MBL was detected in 15 (30% isolates. PCR assay showed that 15 isolates were positive for VIM and these included 10 and 5 isolates showing positive and negative results in phenotypic method of MBL detection testrespectively. Amikacin was found as the most effective antibiotic against the MBL producers in this study.Conclusion: The emergence of bla(VIM-1 producing K. pneumoniae in North of Iran is concerning. Microorganisms producing bla(VIM-1 constitute the prevalent multidrug-resistant population of K. pneumoniae in that region.

  3. A novel beta-lactamase activity from a penicillin-binding protein of Treponema pallidum and why syphilis is still treatable with penicillin.

    Science.gov (United States)

    Cha, Joo Young; Ishiwata, Akihiro; Mobashery, Shahriar

    2004-04-09

    Treponema pallidum, the causative agent of syphilis, is sensitive to penicillins. Yet, an abundant membrane-bound protein of this organism, Tp47, turns over penicillins. It is shown herein that the turnover process is a hydrolytic reaction that results in the corresponding penicilloates, products that have their beta-lactam bonds hydrolyzed. This is the reaction of beta-lactamases, bona fide resistance enzymes to beta-lactam antibiotics. Remarkably, the x-ray structure of Tp47 bears no resemblance to any other beta-lactamases or the related penicillin-binding proteins. Furthermore, evidence is presented that the reaction of Tp47 takes place in the absence of the zinc ion and does not involve intermediary acyl enzyme species. Hence, the beta-lactamase activity of Tp47 is the fifth known mechanism for turnover of beta-lactam antibiotics. Tp47 also exhibits a penicillin binding reaction, in the process of which the enzyme is covalently modified in the active site. The two reactions take place in two different active sites, and the events of the beta-lactamase activity are over 2,000-fold more rapid than the penicillin binding reaction. The level of beta-lactamase activity is high and is held back only by a strong product-inhibition component to the catalytic process. If natural selection would result in a mutant variant of Tp47 that overcomes product inhibition for the beta-lactamase activity, a novel bona fide resistance to penicillins will emerge in Treponema, which will be a disconcerting clinical development. The physiological functions of Tp47 are not known, but it is likely that this is at least a bifunctional enzyme involved in the processing of the Treponema peptidoglycan as a substrate.

  4. Beta-lactamase characterization in Escherichia coli isolates with diminished susceptibility or resistance to extended-spectrum cephalosporins recovered from sick animals in Spain.

    Science.gov (United States)

    Briñas, Laura; Moreno, Miguel Angel; Teshager, Tirushet; Zarazaga, Myriam; Sáenz, Yolanda; Porrero, Concepción; Dominguez, Lucas; Torres, Carmen

    2003-01-01

    A total of 1439 Escherichia coli isolates from sick animals were received from the Spanish Network of Veterinary Antimicrobial Resistance Surveillance (VAV) from 1997 to 2001. Antimicrobial susceptibility tests were performed and diminished susceptibility to cefotaxime and ceftazidime was identified in 2.5% and 2.8% of the isolates, respectively. Beta-lactamase characterization was carried out in the group of 20 E. coli isolates with both characteristics. The MIC ranges of different beta-lactams showed by these 20 isolates were as follows (in microg/ml): ampicillin (64-->256), amoxicillin-clavulanic acid (4-64), ticarcillin (8-->128), cefazolin (32-->256), cefoxitin (4-->128), cefotaxime (1-64), ceftazidime (2-->64), ceftriaxone (0.5-64), imipenem (32). TEM, SHV, CMY, and FOX beta-lactamase genes were analyzed by PCR and sequencing. The beta-lactamase genes detected were the following ones (number of isolates): bla(TEM-1b) (3), bla(TEM-1a) (1), bla(TEM-30f) (2), bla(TEM-1b) + bla(CMY-2) (2), and bla(SHV-12) (1). Sequences of the promoter and/or attenuator region of the chromosomal ampC gene were studied in all the 20 isolates. Mutations at position -42 or -32 were detected in 16 isolates and these mutations were associated with the presence of a TEM type beta-lactamase in 6 isolates. Besides, a high variety of plasmidic beta-lactamases was detected including TEM-30 and CMY-2. To our knowledge, this is the first time that TEM-30 beta-lactamase has been detected in E. coli isolates of animal origin.

  5. “UROPATHOGENS”: PREVALENCE AND ANTIBIOGRAM OF GRAM NEGATIVE BACILLI WITH SPECIAL REFERENCE TO EXTEN DED SPECTRUM BETA LACTAMASE PRODUCTION

    Directory of Open Access Journals (Sweden)

    Vandana

    2012-12-01

    Full Text Available ABSTRACT: This study was performed on culture and sensitivit y of 6,951 urine samples, received in the Department of Microbiology, Christia n Medical College & Hospital, Ludhiana from out patients and in patients having urinary tra ct infection (UTI .A total of 2,276 samples were found out to be culture positive, out of which 1,727 samples yielded gram negative organisms. Various isolates included 1,237 Escheric hia coli (E. coli, 262 Klebsiella pneumoniae,47 Acinetobacter lwoffi, 39 Proteus mirab ilis,39 Enterobacter aerogenes and 03 Pseudomonas aeruginosa. Extended spectrum beta lacta mase (ESBL production was studied in multidrug resistant E. coli. And Klebsiella pneumoni ae, out of which 28.29% E.coli and 30.53% Klebsiella pneumoniae yielded positive results. Our r esults suggest that the physician should be aware of high prevalence of ESBL producing E.coli and Klebsiella pneumonia which are the two common uropathogens, and should plan their therapy re gime accordingly. However, Acinetobacter species were mainly associate d with nosocomial UTI whereas Enterobacter species were isolated mostly from out pa tients. Various uropathogens causing community acquired as well as nosocomial UTI showed poor response to cephalexin whereas resistant strains from both types of UTI exhibited g ood susceptibility to piperacillin/tazobactum combination.

  6. Carbapenemase-Producing Klebsiella pneumoniae in Romania : A Six-Month Survey

    NARCIS (Netherlands)

    Lixandru, Brandusa Elena; Cotar, Ani Ioana; Straut, Monica; Usein, Codruta Romanita; Cristea, Dana; Ciontea, Simona; Tatu-Chitoiu, Dorina; Codita, Irina; Rafila, Alexandru; Nica, Maria; Buzea, Mariana; Baicus, Anda; Ghita, Mihaela Camelia; Nistor, Irina; Tuchilus, Cristina; Indreas, Marina; Antohe, Felicia; Glasner, Corinna; Grundmann, Hajo; Jasir, Aftab; Damian, Maria

    2015-01-01

    This study presents the first characterization of carbapenem-non-susceptible Klebsiella pneumoniae isolates by means of a structured six-month survey performed in Romania as part of an Europe-wide investigation. Klebsiella pneumoniae clinical isolates from different anatomical sites were tested for

  7. Emergence of KPC-producing Klebsiella pneumoniae ST512 isolated from cerebrospinal fluid of a child in Algeria

    Science.gov (United States)

    Bakour, S.; Sahli, F.; Touati, A.; Rolain, J.-M.

    2014-01-01

    We report class A carbapenemase (KPC)-3-producing Klebsiella pneumoniae meningitis in a 6-month-old child in Algeria. Multilocus sequence typing showed that the sequence type obtained corresponded to ST512, an allelic single-locus variant of the pandemic ST258 widely distributed in KPC producers from Europe. To our knowledge, this is the first report of KPC-3-producing K. pneumoniae ST512 in a North African country. PMID:25755890

  8. Emergence of KPC-producing Klebsiella pneumoniae ST512 isolated from cerebrospinal fluid of a child in Algeria

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    S. Bakour

    2015-01-01

    Full Text Available We report class A carbapenemase (KPC-3-producing Klebsiella pneumoniae meningitis in a 6-month-old child in Algeria. Multilocus sequence typing showed that the sequence type obtained corresponded to ST512, an allelic single-locus variant of the pandemic ST258 widely distributed in KPC producers from Europe. To our knowledge, this is the first report of KPC-3-producing K. pneumoniae ST512 in a North African country.

  9. Antibodies against Pseudomonas aeruginosa chromosomal beta-lactamase inpatients with cystic fibrosis are markers of the development of resistance of P. aeruginosa to beta-lactams

    DEFF Research Database (Denmark)

    Ciofu, O; Giwercman, B; Walter-Rasmussen, J

    1995-01-01

    Chromosomal beta-lactamase production is considered to be the most important resistance mechanism of Pseudomonas aeruginosa against beta-lactams. Recently we have detected serum and sputum antibodies against P. aeruginosa chromosomal beta-lactamase (a beta ab), using immunoblotting techniques...... infection and was significantly higher (P beta-lactam courses. A 14 fold increase in a beta ab...... levels occurred during the 14 year period covered by the longitudinal study. The results of this study show that a beta ab to P. aeruginosa is a specific marker for resistance development of P. aeruginosa to beta-lactams....

  10. Biochemical and Structural Characterization of Mycobacterium tuberculosis beta-Lactamase with the Carbapenems Ertapenem and Doripenem

    Energy Technology Data Exchange (ETDEWEB)

    L Tremblay; F Fan; J Blanchard

    2011-12-31

    Despite the enormous success of {beta}-lactams as broad-spectrum antibacterials, they have never been widely used for the treatment of tuberculosis (TB) due to intrinsic resistance that is caused by the presence of a chromosomally encoded gene (blaC) in Mycobacterium tuberculosis. Our previous studies of TB BlaC revealed that this enzyme is an extremely broad-spectrum {beta}-lactamase hydrolyzing all {beta}-lactam classes. Carbapenems are slow substrates that acylate the enzyme but are only slowly deacylated and can therefore act also as potent inhibitors of BlaC. We conducted the in vitro characterization of doripenem and ertapenem with BlaC. A steady-state kinetic burst was observed with both compounds with magnitudes proportional to the concentration of BlaC used. The results provide apparent K{sub m} and k{sub cat} values of 0.18 {micro}M and 0.016 min{sup -1} for doripenem and 0.18 {micro}M and 0.017 min{sup -1} for ertapenem, respectively. FTICR mass spectrometry demonstrated that the doripenem and ertapenem acyl-enzyme complexes remain stable over a time period of 90 min. The BlaC-doripenem covalent complex obtained after a 90 min soak was determined to 2.2 {angstrom}, while the BlaC-ertapenem complex obtained after a 90 min soak was determined to 2.0 {angstrom}. The 1.3 {angstrom} diffraction data from a 10 min ertapenem-soaked crystal revealed an isomerization occurring in the BlaC-ertapenem adduct in which the original {Delta}2-pyrroline ring was tautomerized to generate the {Delta}1-pyrroline ring. The isomerization leads to the flipping of the carbapenem hydroxyethyl group to hydrogen bond to carboxyl O2 of Glu166. The hydroxyethyl flip results in both the decreased basicity of Glu166 and a significant increase in the distance between carboxyl O2 of Glu166 and the catalytic water molecule, slowing hydrolysis.

  11. Evolutionary Trajectories of Beta-Lactamase CTX-M-1 Cluster Enzymes: Predicting Antibiotic Resistance

    Science.gov (United States)

    Novais, Ângela; Comas, Iñaki; Baquero, Fernando; Cantón, Rafael; Coque, Teresa M.; Moya, Andrés; González-Candelas, Fernando; Galán, Juan-Carlos

    2010-01-01

    Extended-spectrum beta-lactamases (ESBL) constitute a key antibiotic-resistance mechanism affecting Gram-negative bacteria, and also an excellent model for studying evolution in real time. A shift in the epidemiology of ESBLs is being observed, which is characterized by the explosive diversification and increase in frequency of the CTX-M-type β-lactamases in different settings. This provides a unique opportunity for studying a protein evolutionary radiation by the sequential acquisition of specific mutations enhancing protein efficiency and fitness concomitantly. The existence of driver antibiotic molecules favoring protein divergence has been investigated by combining evolutionary analyses and experimental site-specific mutagenesis. Phylogenetic reconstruction with all the CTX-M variants described so far provided a hypothetical evolutionary scenario showing at least three diversification events. CTX-M-3 was likely the enzyme at the origin of the diversification in the CTX-M-1 cluster, which was coincident with positive selection acting on several amino acid positions. Sixty-three CTX-M-3 derivatives containing all combinations of mutations under positively selected positions were constructed, and their phenotypic efficiency was evaluated. The CTX-M-3 diversification process can only be explained in a complex selective landscape with at least two antibiotics (cefotaxime and ceftazidime), indicating the need to invoke mixtures of selective drivers in order to understand the final evolutionary outcome. Under this hypothesis, we found congruent results between the in silico and in vitro analyses of evolutionary trajectories. Three pathways driving the diversification of CTX-M-3 towards the most complex and efficient variants were identified. Whereas the P167S pathway has limited possibilities of further diversification, the D240G route shows a robust diversification network. In the third route, drift may have played a role in the early stages of CTX-M-3 evolution

  12. Metallo-beta-lactamases of Pseudomonas aeruginosa--a novel mechanism resistance to beta-lactam antibiotics.

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    Dorota Olszańska

    2008-06-01

    Full Text Available Since about twenty years, following the introduction into therapeutic of news beta-lactam antibiotics (broad-spectrum cephalosporins, monobactams and carbapenems, a very significant number of new beta-lactamases appeared. These enzymes confer to the bacteria which put them, the means of resisting new molecules. The genetic events involved in this evolution are of two types: evolution of old enzymes by mutation and especially appearance of new genes coming for some, from bacteria of the environment. Numerous mechanisms of enzymatic resistance to the carbapenems have been described in Pseudomonas aeruginosa. The important mechanism of inactivation carbapenems is production variety of b-lactam hydrolysing enzymes associated to carbapenemases. The metallo-beta-enzymes (IMP, VIM, SPM, GIM types are the most clinically significant carbapenemases. P. aeruginosa posses MBLs and seem to have acquired them through transmissible genetic elements (plasmids or transposons associated with integron and can be transmission to other bacteria. They have reported worldwide but mostly from South East Asia and Europe. The enzymes, belonging to the molecular class B family, are the most worrisome of all beta-lactamases because they confer resistance to carbapenems and all the beta-lactams (with the exception of aztreonam and usually to aminoglycosides and quinolones. The dissemination of MBLs genes is thought to be driven by regional consumption of extended--spectrum antibiotics (e.g. cephalosporins and carbapenems, and therefore care must be taken that these drugs are not used unnecessarily.

  13. Conjugation of plasmids of Neisseria gonorrhoeae to other Neisseria species: potential reservoirs for the beta-lactamase plasmid.

    Science.gov (United States)

    Genco, C A; Knapp, J S; Clark, V L

    1984-09-01

    The discovery that penicillinase production in Neisseria gonorrhoeae was plasmid mediated and the spread of the beta-lactamase encoding plasmids in gonococcal isolates since 1976, raise the possibility that a nonpathogenic indigenous bacterium could serve as a reservoir for these plasmids. We initiated studies to define the ability of commensal Neisseria species and Branhamella catarrhalis strains, as well as strains of the pathogen Neisseria meningitidis, to serve as recipients in conjugation with Neisseria gonorrhoeae. We found that with N. gonorrhoeae as the donor, 3 of 5 Neisseria cinerea, 2 of 5 Neisseria flava, 0 of 1 Neisseria flavescens, 1 of 3 Neisseria subflava, 0 of 6 B. catarrhalis, 0 of 7 Neisseria lactamica, 1 of 5 Neisseria mucosa, 1 of 7 Neisseria perflava/sicca, and 0 of 13 N. meningitidis strains gave detectable conjugation frequencies (greater than 10(-8). N. cinerea was the only species found to maintain the gonococcal conjugal plasmid (pLE2451). A N. cinerea transconjugant containing pLE2451 was observed to transfer both the beta-lactamase plasmid and pLE2451 to N. gonorrhoeae at high frequency.

  14. Growing Menace of Antibacterial Resistance in Clinical Isolates of Pseudomonas aeruginosa in Nepal: An Insight of Beta-Lactamase Production

    Directory of Open Access Journals (Sweden)

    Shamshul Ansari

    2016-01-01

    Full Text Available Introduction. Pseudomonas aeruginosa is the most frequently isolated organism as it acts as the opportunistic pathogen and can cause infections in immunosuppressed patients. The production of different types of beta-lactamases renders this organism resistant to many commonly used antimicrobials. Therefore, the aim of this study was to document the antibiotic resistance rate in Pseudomonas aeruginosa isolated from different clinical specimens. Methods. Pseudomonas aeruginosa recovered was identified by standard microbiological methods. Antibiotic susceptibility testing was performed by modified Kirby-Bauer disc diffusion method following Clinical and Laboratory Standard Institute (CLSI guidelines and all the suspected isolates were tested for the production of ESBLs, MBLs, and AmpC. Results. Out of total (178 isolates, 83.1% were recovered from the inpatient department (IPD. Majority of the isolates mediated resistance towards the beta-lactam antibiotics, while nearly half of the isolates were resistant to ciprofloxacin. Most of the aminoglycosides used showed resistance rate up to 75% but amikacin proved to be better option. No resistance to polymyxin was observed. ESBLs, MBLs, and AmpC mediated resistance was seen in 33.1%, 30.9%, and 15.7% isolates, respectively. Conclusions. Antibiotic resistance rate and beta-lactamase mediated resistance were high. Thus, regular surveillance of drug resistance is of utmost importance.

  15. Interhospital spread of NDM-7-producing Klebsiella pneumoniae belonging to ST437 in Spain.

    Science.gov (United States)

    Seara, Nieves; Oteo, Jesús; Carrillo, Raquel; Pérez-Blanco, Verónica; Mingorance, Jesús; Gómez-Gil, Rosa; Herruzo, Rafael; Pérez-Vázquez, María; Astray, Jenaro; García-Rodríguez, Julio; Ruiz-Velasco, Luis Moisés; Campos, José; de Burgos, Carmen; Ruiz-Carrascoso, Guillermo

    2015-08-01

    This study describes an interhospital spread of carbapenem-resistant Klebsiella pneumoniae (CRKP) producing NDM-7 carbapenemase that started in December 2013 in Madrid, Spain. NDM-7-producing CRKP were isolated from urine, rectal swabs or blood samples from seven patients admitted to three different hospitals (Hospital Universitario La Paz, Hospital de Cantoblanco and Hospital Central de la Cruz Roja). The isolates were resistant to all antimicrobials tested except colistin and fosfomycin. One blood isolate was susceptible to minocycline and tigecycline but was resistant to fosfomycin. All isolates were closely related by pulsed-field gel electrophoresis (PFGE) and DiversiLab(®) analysis and belonged to multilocus sequence typing (MLST) sequence type 437. In addition, blaNDM-7, blaTEM-1, blaCTX-M-15 and aac(3)-IIa were identified. Family contacts of the index case were negative for NDM-producing bacteria. The outbreak occurred in two separate waves and the cases associated with Hospital de Cantoblanco had been admitted to the same room. Environmental samples from the trap of a sink and a shower in this room were positive for NDM-7-producing CRKP. To our knowledge, this is the first reported worldwide outbreak of NDM-7-producing CRKP. No relationship with the Indian continent, the Balkans or the Middle East could be established. Frequent transfer of aged or chronically ill patients between the facilities involved may have favoured the spread of NDM-7-producing CRKP. The spread of the second wave in Hospital de Cantoblanco probably occurred as a result of transmission from an environmental reservoir.

  16. Outbreak of KPC-3-producing ST15 and ST348 Klebsiella pneumoniae in a Portuguese hospital.

    Science.gov (United States)

    Vubil, D; Figueiredo, R; Reis, T; Canha, C; Boaventura, L; DA Silva, G J

    2017-02-01

    To date, only a few sporadic cases of infections due to Klebsiella pneumoniae carbapenemase (KPC) producers have been reported in Portugal. Here, we report for the first time an outbreak of K. pneumoniae KPC-3 producers in a tertiary-care hospital during 2013. Twenty-seven ertapenem-resistant K. pneumoniae were identified in patients at a tertiary-care hospital during 2013 isolated predominantly from urine (48·1%) and blood (25·9%) cultures. All isolates were highly resistant to β-lactam antibiotics and most showed intermediate resistance to imipenem. The more frequent β-lactamases were TEM- (77·7%), CTX-M- (70·3%) and KPC-type (66·6%). KPC-3 was identified by sequencing. The bla KPC-3 gene was associated with an IncF plasmid, and efficiently transferred to E. coli J53. Pulsed-field gel electrophoresis typing revealed three clusters of isolates which were further characterized by multi-locus sequence typing as ST11, ST15 and ST348. Ertapenem-resistant ST15 was already in circulation in the hospital, related to expression of OmpK36 modified porin, but the other two sequence types had not been previously found in the hospital. We conclude that the IncF plasmid mediated transfer of KPC-3 in the outbreak and that implementation of carbapenemase gene screening in isolates from patients on admission to hospital is advisable in order to control dissemination of these antimicrobial resistance elements.

  17. Double-carbapenem combination as salvage therapy for untreatable infections by KPC-2-producing Klebsiella pneumoniae.

    Science.gov (United States)

    Souli, M; Karaiskos, I; Masgala, A; Galani, L; Barmpouti, E; Giamarellou, H

    2017-02-16

    We report our experience using the double-carbapenem combination as salvage therapy for patients with untreatable infections caused by KPC-2- producing Klebsiella pneumoniae. A total of 27 patients in two institutions in Athens, Greece suffering from complicated urinary tract infections (16) with or without secondary bacteraemia (four and 12 respectively), primary (six) or catheter-related bloodstream infections (two), HAP or VAP (two) and external ventricular drainage infection (one) were treated exclusively with ertapenem and high-dose prolonged infusion meropenem because in-vitro active antimicrobials were unavailable (19) or failed (four) or were contraindicated (six). Most patients presented with severe infections with median APACHE II score of 17 and 11 of those patients (40.7%) had severe sepsis (five) or septic shock (six). The clinical and microbiological success was 77.8 and 74.1% respectively. Crude mortality was 29.6% with attributable mortality of 11.1%. Adverse events, none of them severe, were reported in four patients (14.8%). The double-carbapenem combination as an exclusive regimen represents a safe and valid salvage therapy for untreatable infections by extensively- or pandrug-resistant KPC-producing K.pneumoniae.

  18. Emergence of Klebsiella pneumoniae carbapenemase-producing Proteus mirabilis in Hangzhou, China

    Institute of Scientific and Technical Information of China (English)

    SHENG Zi-ke; LI Jun-jie; SHENG Guo-ping; SHENG Ji-fang; LI Lan-juan

    2010-01-01

    Background Carbapenems are used to treat severe infections caused by multi-drug-resistant organisms, however, the emergence of carbapenem-resistant bacterial isolates is becoming an increasing therapeutic challenge. Since the first Klebsiella (K.) pneumoniae carbapenemase (KPC)-producing K. pneumoniae was reported in 2001, KPC-producing isolates have been found increasingly, specially in Enterobacteriaceae. The aim of this study was to characterize the mechanisms of a carbapenem-resistant Proteus (P.) mirabilis.Methods A carbapenem-resistant P. mirabilis isolate was recovered from pleural drainage fluid of a patient admitted to surgical intensive care unit. Antimicrobial susceptibility testing of the isolate was performed by disk diffusion according to Clinical and Laboratory Standards Institute guidelines, and subsequent minimal inhibitory concentrations were determined with the E-test. Amplification of the blaKPc gene generated a positive band and the PCR products were sequenced subsequently. The plasmid of the isolate was extracted and was successfully transformed into Escherichia (E.) coli DH5α.Results The P. mirabilis isolate was resistant to all detected antimicrobial agents except tigecycline. KPC-2 was confirmed by DNA sequence analysis. The transformant E. coli was resistant to carbapenems. Further study demonstrated that upstream and downstream regions of blaKPC-2 were identical to that observed in K. pneumoniae submitted to GenBank from China in 2007.Conclusion Carbapenem resistance in the P. mirabilis isolate in this study is mainly due to production of KPC-2.

  19. Increasing incidence of carbapenemase-producing Escherichia coli and Klebsiella pneumoniae in Belgian hospitals.

    Science.gov (United States)

    De Laveleye, M; Huang, T D; Bogaerts, P; Berhin, C; Bauraing, C; Sacré, P; Noel, A; Glupczynski, Y

    2017-01-01

    Carbapenemase-producing Enterobacteriaceae are increasingly reported worldwide. The aim of the study was to determine the incidence and molecular epidemiology of carbapenemase-producing (CP) Escherichia coli and Klebsiella pneumoniae (CP-E/K) in Belgium. Eleven hospital-based laboratories collected carbapenem non-susceptible (CNS) isolates of E. coli and K. pneumoniae detected in clinical specimens from January 2013 to December 2014. All CNS strains were tested for carbapenemase production and typed by multilocus sequence typing (MLST) for a 6-month period as part of the European Survey on Carbapenemase-Producing Enterobacteriaceae in Europe (EuSCAPE) structured survey. In addition, an equal number of carbapenem-susceptible isolates collected were preserved as a control group for risk factor analysis. The overall incidence rate of CP-E/K isolates in hospitals increased from 0.124 in 2013 to 0.223 per 1000 admissions in 2014. From November 2013 to April 2014, 30 CP K. pneumoniae [OXA-48 (n = 16), KPC (n = 13), OXA-427 (n = 1)] and five CP E. coli [OXA-48 (n = 3), NDM (n = 1), OXA-427 (n = 1)] isolates were detected in ten hospitals. The 16 OXA-48-producing K. pneumoniae strains were distributed into eight sequence types (STs), while the 13 KPC-producing K. pneumoniae clustered into three STs dominated by ST512 (n = 7) and ST101 (n = 5). Compared to controls, we observed among CP-E/K carriers significantly higher proportion of males, respiratory origins, previous hospitalization, nosocomial setting, and a significantly lower proportion of bloodstream infections. Our study confirms the rapid spread of CP-E/K in Belgian hospitals and the urgent need for a well-structured and coordinated national surveillance plan in order to limit their dissemination.

  20. First isolation and outbreak of OXA-48-producing Klebsiella pneumoniae in an Irish hospital, March to June 2011.

    LENUS (Irish Health Repository)

    O'Brien, D J

    2012-02-01

    Five OXA-48-producing Klebsiella pneumoniae were detected in a tertiary referral hospital in Ireland between March and June 2011. They were found in the clinical isolates of five cases that were inpatients on general surgical wards. None of the cases had received healthcare at a facility outside of Ireland in the previous 12 months. This is the first report of OXA-48-producing K. pneumoniae in Ireland.

  1. An outbreak of colistin-resistant Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae in the Netherlands (July to December 2013), with inter-institutional spread.

    Science.gov (United States)

    Weterings, V; Zhou, K; Rossen, J W; van Stenis, D; Thewessen, E; Kluytmans, J; Veenemans, J

    2015-08-01

    We describe an outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-KP) ST258 that occurred in two institutions (a hospital and a nursing home) in the Netherlands between July and December 2013. In total, six patients were found to be positive for KPC-KP. All isolates were resistant to colistin and exhibited reduced susceptibility to gentamicin and tigecycline. In all settings, extensive environmental contamination was found. Whole genome sequencing revealed the presence of bla KPC-2 and bla SHV-12 genes, as well as the close relatedness of patient and environmental isolates. In the hospital setting, one transmission was detected, despite contact precautions. After upgrading to strict isolation, no further spread was found. After the transfer of the index patient to a nursing home in the same region, four further transmissions occurred. The outbreak in the nursing home was controlled by transferring all KPC-KP-positive residents to a separate location outside the nursing home, where a dedicated nursing team cared for patients. This outbreak illustrates that the spread of pan-resistant Enterobacteriaceae can be controlled, but may be difficult, particularly in long-term care facilities. It, therefore, poses a major threat to patient safety. Clear guidelines to control reservoirs in and outside the hospitals are urgently needed.

  2. Study of Klebsiella pneumoniae producing extended-spectrum β-lactamases against aminoglycosides

    Institute of Scientific and Technical Information of China (English)

    WEI FENG SHI; SU JIAN WANG; JIAN PING QIN

    2007-01-01

    Klebsiella pneumoniae ( K. pneumoniae) is one of the main gram-negative bacilli in clinical practice. Nosocomial infections caused by K. pneumoniae producing extended-spectrum β-lactamases (ESBLs) are very difficult to treat. This paper investigated the resistant characteristics of K. pneumoniae producing ESBLs and their aminoglycoside-modifying enzyme gene expressions including Nacetyltransferases and O-adenyhransferases. Bacteria identification and ESBLs confirmatory tests were performed by Phoenix TM-100 system. And minimum inhibitory concentrations (MICs) of gentamicin,amikacin, kanamycin, tobramycin, netilmicin and neomycin in 53 K. pneumoniae isolates were detected by agar dilution. In addition, six aminoglycoside-modifying enzyme genes were amplified by polymerase chain reaction (PCR) and verified by DNA sequencer. It was found that imipenem and meropenem against 120 K. pneumoniae isolates produced powerful antimicrobial activities. The resistant rates of gentamicin and amikacin were 55.0% and 46.7%, respectively. Except neomycin,MIC50 and MIC90 of gentamicin, amikacin, kanamycin, tobramycin and netilmicin in 53 K. pneumoniae were all > 128 μg/ml, and the resistant rates were 83.0%, 52.3%, 75.5%, 81. 1% and 69.8%, respectively. However, neomycin was only 39.6%. In addition, five modifying enzyme genes, including aac(3)- Ⅰ , aac(3)-Ⅱ, aac(6′) - Ⅰ b, ant(3″) - Ⅰ, ant(2″) - Ⅰ genes, were found in 53 isoahes except aac (6′)-Ⅱ, and their positive rates were 11.3%, 67.9%, 47.2%,1.9 % and 39.6 %, respectively. It was also confirmed by nucleotide sequence analysis that the above resistant genes shared nearly 100% identities with GenBank published genes. The results obtained in the present study indicated that K. pneumoniae producing ESBLs strains are rapidly spreading in our hospital, and their resistance to aminoglycosides may be associated with aminoglycoside-modifying enzyme gene expressions.

  3. Risk factors for KPC-producing Klebsiella pneumoniae: watch out for surgery.

    Science.gov (United States)

    da Silva, Kesia Esther; Maciel, Wirlaine Glauce; Sacchi, Flávia Patussi Correia; Carvalhaes, Cecilia Godoy; Rodrigues-Costa, Fernanda; da Silva, Ana Carolina Ramos; Croda, Mariana Garcia; Negrão, Fábio Juliano; Croda, Julio; Gales, Ana Cristina; Simionatto, Simone

    2016-06-01

    This study describes the molecular characteristics and risk factors associated with carbapenem-resistant Klebsiella pneumoniae strains. Risk factors associated with KPC-producing K. pneumoniae strains were investigated in this case-control study from May 2011 to May 2013. Bacterial identification was performed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined by broth microdilution. Carbapenemase production was assessed by both modified Hodge test (MHT) and ertapenem hydrolysis using MALDI-TOF MS. The presence of β-lactamase-encoding genes was evaluated by PCR and DNA sequencing. Alterations in genes encoding K. pneumoniae outer membrane proteins were analysed by PCR and DNA sequencing as well as SDS-PAGE. Genetic relatedness among strains was determined by pulsed-field gel electrophoresis. This study included 94 patients. Longer hospitalisation, mechanical ventilation, catheters, and previous surgery were associated with KPC-producing K. pneumoniae. Sixty-eight strains showed resistance to carbapenems. Carbapenemase production was detected by MHT in 67 K. pneumoniae strains and by MALDI-TOF MS in 57. The presence of the blaKPC-2 gene was identified in 57 strains. The blaKPC-2 gene was not found in 11 carbapenem-resistant K. pneumoniae; instead, the blaCTX-M-1-like, blaCTX-M-2-like, blaCTX-M-8 like, blaCTX-M-14-like and blaSHV- like genes associated with OmpK35 and OmpK36 alterations were observed. Thirty-three KPC-producing K. pneumoniae strains were clonally related, and patients infected with these strains had a higher mortality rate (78.78 %). Our results show that KPC-producing K. pneumoniae was associated with several healthcare-related risk factors, including recent surgery.

  4. Occurrence of extended-spectrum beta-lactamases (ESBL) in Dutch hospitals

    NARCIS (Netherlands)

    Stobberingh, EE; Arends, J; Hoogkamp-Korstanje, JAA; Goessens, WHF; Visser, MR; Buiting, AGM; Debets-Ossenkopp, YJ; van Ketel, RJ; van Ogtrop, ML; Sabbe, LJM; Voorn, GP; Winter, HLJ; van Zeijl, JH

    1999-01-01

    The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands. 18 isolates were positive for at least one of the screening tests used,

  5. Genotyping and characterization of CTX-M-15 -producing Klebsiella pneumoniae isolated from an Iranian hospital.

    Science.gov (United States)

    Derakhshan, Safoura; Peerayeh, Shahin Najar; Bakhshi, Bita

    2016-08-01

    The aims were to describe the genetic characterization of blaCTX-M-1 group gene in Klebsiella pneumoniae and to investigate the relationship between isolates by MLVA and PFGE. We analyzed 36 CTX-M group 1-ESBL producing K. pneumoniae. rmpA and wcaG virulence genes were identified by PCR. The genetic environment of blaCTX-M-1 was analyzed by PCR and sequencing. Plasmid replicons were determined using PCR-based replicon typing. The isolates were typed by MLVA and PFGE. All blaCTX-M-1 were blaCTX-M-15. The wcaG and rmpA were detected in 1 and 2 isolates, respectively. IncF were the most frequently detected replicons (63.88%). In all isolates, ISEcp1 was found upstream and orf477 downstream of blaCTX-M-15, IS26 was found in two isolates. MLVA identified 20 MLVA types, whereas PFGE identified 25 different profiles. The dissemination of CTX-M-15 in our isolates was due to the clonal spread of isolates and to the genetic transfer of mobile elements among unrelated strains.

  6. Emergence of KPC-producing Klebsiella pneumoniae in Uruguay: infection control and molecular characterization

    Science.gov (United States)

    Marquez, C; Ingold, A; Echeverría, N; Acevedo, A; Vignoli, R; García-Fulgueiras, V; Viroga, J; Gonzalez, O; Odizzio, V; Etulain, K; Nuñez, E; Albornoz, H; Borthagaray, G; Galiana, A

    2014-01-01

    We describe the first outbreak of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP), the infection control measures adopted and the shift in resistance patterns of isolates during antibiotic treatment. The ST258 KPC-KP strain exhibited a multiresistant antibiotic phenotype including co-resistance to gentamycin, colistin and tigecycline intermediate susceptibility. Isolates before and after treatment had different behaviour concerning their antibiotic susceptibility and the population analysis profile study. A progressive increase in the aminoglycosides (acquiring amicacin resistance) and β-lactam MICs, and a decreased susceptibility to fosfomycin was observed throughout the administration of combined antimicrobial regimens including meropenem. A high meropenem resistance KPC-KP homogeneous population (MIC 256 Jg/mL), could arise from the meropenem heterogeneous low-level resistance KPC-KP population (MIC 8 Jg/mL), by the selective pressure of the prolonged meropenem therapy. The kpc gene was inserted in a Tn4401 isoform a, and no transconjugants were detected. The core measures adopted were successful to prevent evolution towards resistance dissemination. PMID:25356345

  7. Emergence of KPC-producing Klebsiella pneumoniae in Uruguay: infection control and molecular characterization

    Directory of Open Access Journals (Sweden)

    C. Marquez

    2014-05-01

    Full Text Available We describe the first outbreak of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP, the infection control measures adopted and the shift in resistance patterns of isolates during antibiotic treatment. The ST258 KPC-KP strain exhibited a multiresistant antibiotic phenotype including co-resistance to gentamycin, colistin and tigecycline intermediate susceptibility. Isolates before and after treatment had different behaviour concerning their antibiotic susceptibility and the population analysis profile study. A progressive increase in the aminoglycosides (acquiring amicacin resistance and β-lactam MICs, and a decreased susceptibility to fosfomycin was observed throughout the administration of combined antimicrobial regimens including meropenem. A high meropenem resistance KPC-KP homogeneous population (MIC 256 Jg/mL, could arise from the meropenem heterogeneous low-level resistance KPC-KP population (MIC 8 Jg/mL, by the selective pressure of the prolonged meropenem therapy. The kpc gene was inserted in a Tn4401 isoform a, and no transconjugants were detected. The core measures adopted were successful to prevent evolution towards resistance dissemination.

  8. Emergence of KPC-producing Klebsiella pneumoniae in Uruguay: infection control and molecular characterization.

    Science.gov (United States)

    Marquez, C; Ingold, A; Echeverría, N; Acevedo, A; Vignoli, R; García-Fulgueiras, V; Viroga, J; Gonzalez, O; Odizzio, V; Etulain, K; Nuñez, E; Albornoz, H; Borthagaray, G; Galiana, A

    2014-05-01

    We describe the first outbreak of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP), the infection control measures adopted and the shift in resistance patterns of isolates during antibiotic treatment. The ST258 KPC-KP strain exhibited a multiresistant antibiotic phenotype including co-resistance to gentamycin, colistin and tigecycline intermediate susceptibility. Isolates before and after treatment had different behaviour concerning their antibiotic susceptibility and the population analysis profile study. A progressive increase in the aminoglycosides (acquiring amicacin resistance) and β-lactam MICs, and a decreased susceptibility to fosfomycin was observed throughout the administration of combined antimicrobial regimens including meropenem. A high meropenem resistance KPC-KP homogeneous population (MIC 256 Jg/mL), could arise from the meropenem heterogeneous low-level resistance KPC-KP population (MIC 8 Jg/mL), by the selective pressure of the prolonged meropenem therapy. The kpc gene was inserted in a Tn4401 isoform a, and no transconjugants were detected. The core measures adopted were successful to prevent evolution towards resistance dissemination.

  9. Carbapenemase-producing Klebsiella pneumoniae: (when) might we still consider treating with carbapenems?

    Science.gov (United States)

    Daikos, G L; Markogiannakis, A

    2011-08-01

    Infections caused by carbapenemase-producing Klebsiella pneumoniae (CPKP) are increasing in frequency worldwide. CPKP isolates exhibit extensive drug resistance phenotypes, complicate therapy, and limit treatment options. Although CPKP isolates are often highly resistant to carbapenems, a proportion of these have relatively low MICs for carbapenems, raising the question of whether this class of agents has any therapeutic potential against CPKP infections. Results from animal studies and patient outcome data indicate that carbapenems retain meaningful in vitro activity against CPKP isolates with carbapenem MICs of ≤ 4 mg/L. Accumulating clinical experience also suggests that the therapeutic efficacy of carbapenems against CPKP isolates with MICs of ≤ 4 mg/L is enhanced when these agents are administered in combination with another active antibiotic. The results of human pharmacokinetic/pharmacodynamic studies are in line with the above observations; it is highly probable that a high-dose/prolonged-infusion regimen of a carbapenem would attain a time above the MIC value of 50% for CPKP isolates with MICs up to 4 mg/L, ensuring acceptable drug exposure and favourable treatment outcome. The analyses summarized in this review support the notion that carbapenems have their place in the treatment of CPKP infections and that the currently proposed EUCAST clinical breakpoints could direct physicians in making treatment decisions.

  10. First Report of Klebsiella pneumoniae-Carbapenemase-3-Producing Escherichia coli ST479 in Poland

    Directory of Open Access Journals (Sweden)

    Dominika Ojdana

    2015-01-01

    Full Text Available An increase in the antibiotic resistance among members of the Enterobacteriaceae family has been observed worldwide. Multidrug-resistant Gram-negative rods are increasingly reported. The treatment of infections caused by Escherichia coli and other Enterobacteriaceae has become an important clinical problem associated with reduced therapeutic possibilities. Antimicrobial carbapenems are considered the last line of defense against multidrug-resistant Gram-negative bacteria. Unfortunately, an increase of carbapenem resistance due to the production of Klebsiella pneumoniae carbapenemase (KPC enzymes has been observed. In this study we describe the ability of E. coli to produce carbapenemase enzymes based on the results of the combination disc assay with boronic acid performed according to guidelines established by the European Community on Antimicrobial Susceptibility Testing (EUCAST and the biochemical Carba NP test. Moreover, we evaluated the presence of genes responsible for the production of carbapenemases (blaKPC, blaVIM, blaIMP, blaOXA-48 and genes encoding other β-lactamases (blaSHV, blaTEM, blaCTX-M among E. coli isolate. The tested isolate of E. coli that possessed the blaKPC-3 and blaTEM-34 genes was identified. The tested strain exhibited susceptibility to colistin (0.38 μg/mL and tigecycline (1 μg/mL. This is the first detection of blaKPC-3 in an E. coli ST479 in Poland.

  11. Amino acid sequence requirements at residues 69 and 238 for the SME-1 beta-lactamase to confer resistance to beta-lactam antibiotics.

    Science.gov (United States)

    Majiduddin, Fahd K; Palzkill, Timothy

    2003-03-01

    Carbapenem antibiotics have been used to counteract resistant strains of bacteria harboring beta-lactamases and extended-spectrum beta-lactamases. Four enzymes from the class A group of beta-lactamases, NMC-A, IMI-1, SME-1, and KPC-1, efficiently hydrolyze carbapenem antibiotics. Sequence comparisons and structural information indicate that cysteines at amino acid residues 69 and 238, which are conserved in all four of these enzymes, form a disulfide bond that is unique to these beta-lactamases. To test whether this disulfide bond is required for catalytic activity, the codons for residues Cys69 and Cys238 were randomized individually and simultaneously by PCR-based mutagenesis to create random replacement libraries for these positions. Mutants that were able to confer resistance to ampicillin, imipenem, or cefotaxime were selected from these libraries. The results indicate that positions Cys69 and Cys238 are critical for hydrolysis of all of the antibiotics tested, suggesting that the disulfide bond is generally required for this enzyme to catalyze the hydrolysis of beta-lactam antibiotics.

  12. Use of a non-radioactive hybridisation assay for direct detection of gram-negative bacteria carrying TEM beta-lactamase genes in infected urine.

    Science.gov (United States)

    Carter, G I; Towner, K J; Pearson, N J; Slack, R C

    1989-02-01

    DNA in infected urines from 81 patients with urinary tract infection was hybridised directly with a non-radioactive DNA probe specific for bacterial genes coding for TEM-type beta-lactamase. The results were assessed by means of a computerised image analysis system and compared with those obtained following isolation of the infecting organism, conventional sensitivity testing and isoelectric focusing (IEF) procedures for the detection of TEM-type beta-lactamase. Of the 27 ampicillin-resistant gram-negative organisms isolated in pure culture from the urines, 14 were shown by both hybridisation and IEF to carry a gene for TEM beta-lactamase production. Only four discordant results were obtained: three "false positive" direct hybridisation results, one due to urine pigmentation, and one, possibly, to a TEM beta-lactamase gene which was not being expressed, and one "false negative" result due to insufficient cell numbers in the urine. The system is capable of screening large numbers of samples and is applicable to any gene for which a suitable DNA probe is available.

  13. Detection of CMY-2, CTX-M-14, and SHV-12 beta-lactamases in Escherichia coli fecal-sample isolates from healthy chickens.

    Science.gov (United States)

    Briñas, Laura; Moreno, Miguel Angel; Zarazaga, Myriam; Porrero, Concepción; Sáenz, Yolanda; García, María; Dominguez, Lucas; Torres, Carmen

    2003-06-01

    Genes encoding the CMY-2, CTX-M-14, and SHV-12 beta-lactamases were detected in three of five Escherichia coli isolates from fecal samples from healthy chickens which showed resistance or diminished susceptibility to extended-spectrum cephalosporins. A -42 mutation at the promoter region of the ampC gene was detected in the other two isolates.

  14. Characterization of paired mucoid/non-mucoid Pseudomonas aeruginosa isolates from Danish cystic fibrosis patients: antibiotic resistance, beta-lactamase activity and RiboPrinting

    DEFF Research Database (Denmark)

    Ciofu, O; Fussing, V; Bagge, N;

    2001-01-01

    The purpose of this study was to characterize 42 paired mucoid and non-mucoid Danish cystic fibrosis (CF) Pseudomonas aeruginosa isolates collected in 1997, by RiboPrinting, antibiotic susceptibility and beta-lactamase activity. Eight P. aeruginosa isolates collected before 1991 were included for...

  15. Conventional NK cells can produce IL-22 and promote host defense in Klebsiella pneumoniae pneumonia.

    Science.gov (United States)

    Xu, Xin; Weiss, Ido D; Zhang, Hongwei H; Singh, Satya P; Wynn, Thomas A; Wilson, Mark S; Farber, Joshua M

    2014-02-15

    It was reported that host defense against pulmonary Klebsiella pneumoniae infection requires IL-22, which was proposed to be of T cell origin. Supporting a role for IL-22, we found that Il22(-/-) mice had decreased survival compared with wild-type mice after intratracheal infection with K. pneumoniae. Surprisingly, however, Rag2(-/-) mice did not differ from wild-type mice in survival or levels of IL-22 in the lungs postinfection with K. pneumoniae. In contrast, K. pneumoniae-infected Rag2(-/-)Il2rg(-/-) mice failed to produce IL-22. These data suggested a possible role for NK cells or other innate lymphoid cells in host defense and production of IL-22. Unlike NK cell-like innate lymphoid cells that produce IL-22 and display a surface phenotype of NK1.1(-)NKp46(+)CCR6(+), lung NK cells showed the conventional phenotype, NK1.1(+)NKp46(+)CCR6(-). Mice depleted of NK cells using anti-asialo GM1 showed decreased survival and higher lung bacterial counts, as well as increased dissemination of K. pneumoniae to blood and liver, compared with control-treated mice. NK cell depletion also led to decreased production of IL-22 in the lung. Within 1 d postinfection, although there was no increase in the number of lung NK cells, a subset of lung NK cells became competent to produce IL-22, and such cells were found in both wild-type and Rag2(-/-) mice. Our data suggest that, during pulmonary infection of mice with K. pneumoniae, conventional NK cells are required for optimal host defense, which includes the production of IL-22.

  16. Ceftobiprole medocaril (BAL5788) treatment of experimental Haemophilus influenzae, Enterobacter cloacae, and Klebsiella pneumoniae murine pneumonia.

    Science.gov (United States)

    Rouse, Mark S; Hein, Melanie M; Anguita-Alonso, Paloma; Steckelberg, James M; Patel, Robin

    2006-08-01

    Ceftobiprole (BAL9141) is an investigational cephalosporin active against methicillin- and vancomycin-resistant staphylococci administered as a water-soluble prodrug, ceftobiprole medocaril (BAL5788). Using an immunocompetent murine pneumonia model of Haemophilus influenzae, Enterobacter cloacae, or extended-spectrum beta-lactamase (ESBL) nonproducing or producing Klebsiella pneumoniae pneumonia, we compared results of treatment with ceftobiprole medocaril (71 mg/kg, sc, qid), ceftriaxone (50 mg/kg, im, bid), or cefepime (50 mg/kg, ip, q.i.d.). Results were expressed as median and 25th to 75th percentile log10 colony forming units per gram of lung tissue. Ceftobiprole, ceftriaxone, and cefepime were each more active than was no treatment and were equally active for treatment of experimental H. influenzae, E. cloacae, or ESBL-nonproducing K. pneumoniae pneumonia. For ESBL-producing K. pneumoniae, no differences were detected between no treatment and treatment with ceftobiprole, ceftriaxone, or cefepime. Ceftobiprole is active against H. influenzae, E. cloacae, and ESBL-nonproducing K. pneumoniae in an immunocompetent experimental murine pneumonia model.

  17. Structures of ceftazidime and its transition-state analogue in complex with AmpC beta-lactamase: Implications for resistance mutations and inhibitor design

    Energy Technology Data Exchange (ETDEWEB)

    Powers, R.A.; Caselli, E.; Focia, P.J.; Prati, F.; Shoichet, B.K.

    2010-03-08

    Third-generation cephalosporins are widely used {beta}-lactam antibiotics that resist hydrolysis by {beta}-lactamases. Recently, mutant {beta}-lactamases that rapidly inactivate these drugs have emerged. To investigate why third-generation cephalosporins are relatively stable to wild-type class C {beta}-lactamases and how mutant enzymes might overcome this, the structures of the class C {beta}-lactamase AmpC in complex with the third-generation cephalosporin ceftazidime and with a transition-state analogue of ceftazidime were determined by X-ray crystallography to 2.0 and 2.3 {angstrom} resolution, respectively. Comparison of the acyl-enzyme structures of ceftazidime and loracarbef, a {beta}-lactam substrate, reveals that the conformation of ceftazidime in the active site differs from that of substrates. Comparison of the structures of the acyl-enzyme intermediate and the transition-state analogue suggests that ceftazidime blocks formation of the tetrahedral transition state, explaining why it is an inhibitor of AmpC. Ceftazidime cannot adopt a conformation competent for catalysis due to steric clashes that would occur with conserved residues Val211 and Tyr221. The X-ray crystal structure of the mutant {beta}-lactamase GC1, which has improved activity against third-generation cephalosporins, suggests that a tandem tripeptide insertion in the {Omega} loop, which contains Val211, has caused a shift of this residue and also of Tyr221 that would allow ceftazidime and other third-generation cephalosporins to adopt a more catalytically competent conformation. These structural differences may explain the extended spectrum activity of GC1 against this class of cephalosporins. In addition, the complexed structure of the transition-state analogue inhibitor (K{sub i} 20 nM) with AmpC reveals potential opportunities for further inhibitor design.

  18. Prolonged febrile illness due to CTX-M-15 extendedspectrum β-lactamase-producing Klebsiella pneumoniae infection in Nigeria

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    Oladipo A. Aboderin

    2011-12-01

    Full Text Available We report on an 8-year-old patient with septicaemia unresponsive to therapy for five weeks. Undetected, extended-spectrum β-lactamase (ESBL production by the infecting Klebsiella strain was regarded as responsible for treatment failure. Intravenously administered imipenem during the sixth week led to sustained resolution of fever. Resource-limited hospitals can incur prohibitive costs from ESBL-producer infections because of diagnostic limitations and consequent treatment failure involving prolonged supportive therapy.

  19. Detection of extended spectrum beta-lactamases and resistance in members of the Enterobacteriaceae family isolated from healthy sheep and dogs in Umuarama, Paraná, Brazil

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    Patricia Alves de Oliveira

    2016-04-01

    Full Text Available Bacterial resistance is a primary public health concern worldwide. Within this context, pets and breeding animals act as reservoirs for multidrug-resistant bacteria (MR, such as those producing extended spectrum beta-lactamases (ESBL and those presenting plasmid-mediated quinolone resistance (PMQR. The aim of this study was to detect the presence of ESBL and PMQR in members of the Enterobacteriaceae family, isolated from healthy sheep and dogs from non-intense farming rural properties in the Umuarama region of Paraná, Brazil. A total of 81 oral and rectal swabs from dogs and sheep from 11 small rural properties were analyzed. These swabs were inoculated in tubes containing brain heart infusion broth (BHI, and the resulting cultures were inoculated on MacConkey agar (MAC supplemented with 10 ?g/mL cefotaxime for the selection of ESBL producers. The cells were also plated on MAC supplemented with 50 ?g/mL nalidixic acid for selecting quinolone-resistant enterobacteria. The bacterial isolates were subjected to biochemical identification tests, antibiograms, double-disk synergic tests, and polymerase chain reaction analysis for resistance-inducing genes (blaESBL, qnr, and genes encoding efflux pump and acetylases. Four (5.00% bacterial isolates (3 Escherichia coli and 1 Morganella morganii resistant to cephalosporins and/or quinolones were identified; of these, three (75% isolates were from sheep and one (25% from a dog. These findings indicate the presence of MR bacteria in the normal microbiota of the animals studied. Animals colonized with such bacteria can contribute to the dissemination of antimicrobial resistance to other animals, environment, and/or human beings and can harbor endogenous infections in unfavorable conditions, which have poor prognosis due to the limited therapeutic options.

  20. Role of ser-237 in the substrate specificity of the carbapenem-hydrolyzing class A beta-lactamase Sme-1.

    Science.gov (United States)

    Sougakoff, W; Naas, T; Nordmann, P; Collatz, E; Jarlier, V

    1999-08-17

    The role of the serine residue found at position 237 in the carbapenemase Sme-1 has been investigated by constructing a mutant in which Ser-237 was replaced by an alanine. The S237A mutant showed a catalytic behavior against penicillins and aztreonam very similar to that of Sme-1. By contrast, S237A was characterized by a reduced catalytic efficiency against cephems, such as cephalothin and cephaloridine. In addition, the weak activity of Sme-1 against the cephamycin cefoxitin was hardly detectable with the mutant enzyme. Finally, the Ser-237-->Ala mutation resulted in a marked decrease in catalytic activity against imipenem, showing that Ser-237 contributes to the carbapenemase activity of the class A beta-lactamase Sme-1.

  1. An overview of extended-spectrum beta-lactamases in veterinary medicine and their public health consequences.

    Science.gov (United States)

    Nóbrega, Diego Borin; Brocchi, Marcelo

    2014-08-13

    Serious human and animal infections caused by bacteria are usually treated with beta-lactams. Extended-spectrum beta-lactamases (ESBLs) constitute the most clinically and economically important enzymes that are able to hydrolyze and inactivate beta-lactam antibiotics in veterinary medicine. The spread of ESBLs represents a serious threat to healthcare systems, drastically undermining therapeutic options. The relationship between drug usage and the emergence of resistance has been extensively reported. Nevertheless, the use of antimicrobials in veterinary medicine and the emergence of ESBLs in animals remains a matter of debate. Moreover, there is still controversy about whether antibiotic usage in farm animals poses a potential public health risk. This review will (i) deal with aspects related to the presence of ESBLs in veterinary medicine, (ii) its link with human medicine, and (iii) discuss strategies to be implemented to preserve antimicrobial effectiveness. New insights relative to old questions concerning antimicrobial use in domestic animals are also presented.

  2. [The incidence of extended spectrum beta-lactamases in Proteus mirabilis strains isolated in 2007-2009].

    Science.gov (United States)

    Kwiecińska-Piróg, Joanna; Bogiel, Tomasz; Gospodarek, Eugenia

    2010-01-01

    Proteus sp. rods are opportunistic human pathogens, isolated mainly from urinary tract infections. They are naturally susceptible to most antimicrobials. However, acquisition of genes for extended spectrum beta-lactamases on plasmids and irrational antimicrobial treatment increase amount of multidrug resistant strains and lead to their selection. The aim of this study was to evaluate production of ESBLs by double disc synergy test and antimicrobial susceptibility of P mirabilis strains by disc diffusion method. Strains included into the study were isolated from patients of dr A. Jurasz University Hospital No 1 in Bydgoszcz between 2007 and 2009. P mirabilis strains were isolated mainly from urine. In this study 10,4%, 18,7% and 14,4% ESBL(+) P mirabilis strains were isolated in 2007, 2008, 2009, respectively. Resistance to majority of the investigated antimicrobials was observed in ESBL(+) P mirabilis strains.

  3. Site-protected fixation and immobilization of Escherichia coli cells displaying surface-anchored beta-lactamase.

    Science.gov (United States)

    Freeman, A; Abramov, S; Georgiou, G

    1999-01-20

    Bacteria displaying heterologous receptors or enzymes on their surface hold great potential as whole-cell adsorbents and biocatalysts, respectively. For industrial applications, such surface-engineered cells need to be killed and chemically fixed to prevent disintegration and leakage of the displayed proteins under process conditions. It is also highly desirable to couple the chemically stabilized cells onto a solid support matrix for additional mechanical stability, flexibility in reactor choice, and easy separation from processed medium. Recently, we described the development of a readily scalable methodology for cell killing, fixation, and outer membrane stabilization via glutaraldehyde fixation followed by secondary crosslinking (Freeman, A., Abramov, S. and Georgiou, G. 1996. Biotechnol. Bioeng. 52: 625-630). Glutaraldehyde treatment was also found, however, to reduce the specific activity of a model enzyme, beta-lactamase displayed on the surface of E. coli. Here, we show that crosslinking carried out in the presence of beta-lactamase inhibitors, namely phenyl boronic acid or sodium borate, protects the active site from chemical modification resulting in up to threefold higher specific activities without affecting the cell-stabilizing effect of the glutaraldehyde treatment. To prepare an immobilized whole cell biocatalyst, residual unreacted surface aldehyde groups were employed to immobilize covalently the fixed bacteria onto chitosan-coated cellulose powder. The binding of the bacteria onto chitosan-coated cellulose was quantitative up to cell loading of 83 mg dry cell weight/g of support. Cell immobilization did not introduce mass transfer limitations and created only a modest reduction in Vmax. Thus, chemical crosslinking, affected in presence of reversible active-site inhibitors and coupled with cell immobilization on chitosan-coated cellulose represents a widely useful methodology for the process application of recombinant bacteria displaying surface

  4. Activity of Antimicrobial Combinations against KPC-2-Producing Klebsiella pneumoniae in a Rat Model and Time-Kill Assay

    Science.gov (United States)

    Aranha Junior, Ayrton Alves; Arend, Lavinia Nery; Ribeiro, Vanessa; Zavascki, Alexandre Prehn; Tuon, Felipe Francisco

    2015-01-01

    This study evaluated the efficacy of tigecycline (TIG), polymyxin B (PMB), and meropenem (MER) in 80 rats challenged with Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae infection. A time-kill assay was performed with the same strain. Triple therapy and PMB+TIG were synergistic, promoted 100% survival, and produced negative peritoneal cultures, while MER+TIG showed lower survival and higher culture positivity than other regimens (P = 0.018) and was antagonistic. In vivo and in vitro studies showed that combined regimens, except MER+TIG, were more effective than monotherapies for this KPC-producing strain. PMID:25896686

  5. Predictive Models for Identification of Hospitalized Patients Harboring KPC-Producing Klebsiella pneumoniae

    Science.gov (United States)

    Trecarichi, Enrico Maria; Tumietto, Fabio; Del Bono, Valerio; De Rosa, Francesco Giuseppe; Bassetti, Matteo; Losito, Angela Raffaella; Tedeschi, Sara; Saffioti, Carolina; Corcione, Silvia; Giannella, Maddalena; Raffaelli, Francesca; Pagani, Nicole; Bartoletti, Michele; Spanu, Teresa; Marchese, Anna; Cauda, Roberto; Viscoli, Claudio; Viale, Pierluigi

    2014-01-01

    The production of Klebsiella pneumoniae carbapenemases (KPCs) by Enterobacteriaceae has become a significant problem in recent years. To identify factors that could predict isolation of KPC-producing K. pneumoniae (KPCKP) in clinical samples from hospitalized patients, we conducted a retrospective, matched (1:2) case-control study in five large Italian hospitals. The case cohort consisted of adult inpatients whose hospital stay included at least one documented isolation of a KPCKP strain from a clinical specimen. For each case enrolled, we randomly selected two matched controls with no KPCKP-positive cultures of any type during their hospitalization. Matching involved hospital, ward, and month/year of admission, as well as time at risk for KPCKP isolation. A subgroup analysis was also carried out to identify risk factors specifically associated with true KPCKP infection. During the study period, KPCKP was isolated from clinical samples of 657 patients; 426 of these cases appeared to be true infections. Independent predictors of KPCKP isolation were recent admission to an intensive care unit (ICU), indwelling urinary catheter, central venous catheter (CVC), and/or surgical drain, ≥2 recent hospitalizations, hematological cancer, and recent fluoroquinolone and/or carbapenem therapy. A Charlson index of ≥3, indwelling CVC, recent surgery, neutropenia, ≥2 recent hospitalizations, and recent fluoroquinolone and/or carbapenem therapy were independent risk factors for KPCKP infection. Models developed to predict KPCKP isolation and KPCKP infection displayed good predictive power, with the areas under the receiver-operating characteristic curves of 0.82 (95% confidence interval [CI], 0.80 to 0.84) and 0.82 (95% CI, 0.80 to 0.85), respectively. This study provides novel information which might be useful for the clinical management of patients harboring KPCKP and for controlling the spread of this organism. PMID:24733460

  6. Polymyxin B in combination with meropenem against carbapenemase-producing Klebsiella pneumoniae: pharmacodynamics and morphological changes.

    Science.gov (United States)

    Sharma, Rajnikant; Patel, Saloni; Abboud, Cely; Diep, John; Ly, Neang S; Pogue, Jason M; Kaye, Keith S; Li, Jian; Rao, Gauri G

    2017-02-01

    Combination therapy provides a useful therapeutic approach to overcome resistance until new antibiotics become available. In this study, the pharmacodynamics, including the morphological effects, of polymyxin B (PMB) and meropenem alone and in combination against KPC-producing Klebsiella pneumoniae clinical isolates was examined. Ten clinical isolates were obtained from patients undergoing treatment for mediastinitis. KPCs were identified and MICs were measured using microbroth dilution. Time-kill studies were conducted over 24 h with PMB (0.5-16 mg/L) and meropenem (20-120 mg/L) alone or in combination against an initial inoculum of ca. 10(6) CFU/mL. Scanning electron microscopy (SEM) was employed to analyse changes in bacterial morphology after treatment, and the log change method was used to quantify the pharmacodynamic effect. All isolates harboured the blaKPC-2 gene and were resistant to meropenem (MICs ≥8 mg/L). Clinically relevant PMB concentrations (0.5, 1.0 and 2.0 mg/L) in combination with meropenem were synergistic against all isolates except BRKP28 (polymyxin- and meropenem-resistant, both MICs >128 mg/L). All PMB and meropenem concentrations in combination were bactericidal against polymyxin-susceptible isolates with meropenem MICs ≤16 mg/L. SEM revealed extensive morphological changes following treatment with PMB in combination with meropenem compared with the changes observed with each individual agent. Additionally, morphological changes decreased with increasing resistance profiles of the isolate, i.e. increasing meropenem MIC. These antimicrobial effects may not only be a summation of the effects due to each antibiotic but also a result of differential action that likely inhibits protective mechanisms in bacteria.

  7. New Polymyxin B Dosing Strategies To Fortify Old Allies in the War against KPC-2-Producing Klebsiella pneumoniae.

    Science.gov (United States)

    Bulman, Zackery P; Satlin, Michael J; Chen, Liang; Kreiswirth, Barry N; Shin, Beom Soo; Walsh, Thomas J; Holden, Patricia N; Forrest, Alan; Nation, Roger L; Li, Jian; Tsuji, Brian T

    2017-04-01

    Pharmacodynamics of a polymyxin B, meropenem, and rifampin triple combination were examined against Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) ST258. In time-kill experiments against three KPC-Kp isolates, triple combination generated 8.14, 8.19, and 8.29 log10 CFU/ml reductions within 24 h. In the hollow-fiber infection model, the triple combination caused maximal killing of 5.16 log10 CFU/ml at 78 h and the time required for regrowth was more than doubled versus the 2-drug combinations. Remarkably, combinations with a high single-dose polymyxin B burst plus rifampin preserved KPC-Kp polymyxin susceptibility (MIC240 h = 0.5 mg/liter) versus the same combination with traditionally dosed polymyxin B, where resistance was amplified (MIC240 h = 32 mg/liter).

  8. Rapid typing of extended-spectrum β-lactamase- and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae isolates by use of spectracell RA

    NARCIS (Netherlands)

    H.F.M. Willemse-Erix (Diana); T.C. Bakker Schut (Tom); F. Slagboom-Bax (Femke); J-W. Jachtenberg (Jan-Willem); N. Lemmens-den Toom; C.C. Papagiannitsis (Costas); K. Kuntaman (Kuntaman); G.J. Puppels (Gerwin); A.F. van Belkum (Alex); J.A. Severin (Juliëtte); W.H.F. Goessens (Wil); K. Maquelin (Kees)

    2012-01-01

    textabstractEnterobacteriaceae are important pathogens of both nosocomial and community-acquired infections. In particular, strains with broad-spectrum beta-lactamases increasingly cause problems in health care settings. Rapid and reliable typing systems are key tools to identify transmission, so th

  9. Emergence of Klebsiella pneumoniae carbapenemase-producing Escherichia coli sequence type 131 in Hangzhou, China

    Institute of Scientific and Technical Information of China (English)

    Lou Zhengqing; Qi Yan; Qian Xiang; Yang Wei; Wei Zeqing

    2014-01-01

    Background Klebsiella pneumoniae carbapenemase (KPC)-producing Escherichia (E.) coil has been reported in China since 2008.However,there is no information about the molecular epidemiology of KPC-producing E.coil in China.In this study,we aimed to investigate the sequence type (ST) and characteristics of KPC-producing E.coil isolates in China.Methods Three carbapenem-resistant isolates of E.coil (E1,E2,and E3) from one teaching hospital in Hangzhou covering a one year period were analyzed.Antibiotic susceptibility was determined by Etest.Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used for epidemiological analysis.The genetic structure around blaKPC,the major plasmid incompatibility typing,and the identification of 3-lactamase gene types were performed by PCR and the positive products were subsequently sequenced.Plasmids were analyzed by transformation,restriction,and Southern blotting.Results PFGE demonstrated that patterns of isolates E1 and E2 were clonally-related and designated as patterns A1 and A2; pattern of isolate E3 was different and designated as pattern B.MLST analysis showed that the three isolates displayed one common sequence type ST131.The identification of bla gene types by PCR and sequencing showed that blaKPC-2,blaCTX-M-14,and blaTEM-1 were detected in all three isolates.All three isolates carried a KPC-2-encoding plasmid of the IncN replicon.Plasmid analysis and hybridization experiments showed that the isolates were found simultaneously to carry two or four plasmids.The blaKPc-2 gene in E1 and E2 was located in a plasmid with size of ca.50 kb.However,the blaKPC-2 gene in E3 was located in a plasmid with size of ca.130 kb.Conclusions E.coil ST131 with KPC-2 β-1actamase has emerged in China,which enlarges the geographical area where the ST131 KPC-oroducing E.coil strains have diffused.

  10. Prevalence of SHV/CTX-M/TEM (ESBL Beta-lactamase Resistance Genes in Escherichia Coli Isolated from Urinary Tract Infections in Tehran, Iran

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    Yazdi M

    2010-01-01

    Full Text Available Background and objectives: Beta-lactamase enzymes are the most causes ofresistance to antibiotics among gram-negative bacteria. Nowadays, Infectionsdue to ESBLs are being increased throughout the world and is considered as anew burden to the health systems. This study aimed at determining thesensitivity pattern of E.coli isolates to beta-lactam antibiotics, andinvestigating the presence of blaCTX-M, blaTEM, and blaSHV genes in the urinesamples..Material and Methods: In this study, 244 E.coli isolates were screened in2009-2010. The antibiotic susceptibility of E. coli isolates were determined bydisc-diffusion method. Antimicrobial agents tested were cefoxatime,ceftazidime, imipenem, nalidixic acid, and ciprofloxacin. The combined disctest was used to confirm the results. The results were compared to the Clinicaland Laboratory Standards Institute (CLSI and ESBL positive isolates werefurther investigated for the presence of blaCTX-M, blaTEM, and blaSHV genes byPCR.Results: Of 244 E. coli isolates, 116 (47.1% are resistant to Ceftazidime, and96 (39.2% to cefoxatime. Also, 109 (44.3% isolates are ESBL positive.blaCTX-M, blaTEM, and blaSHV genes are found among 95 (87.1%, 75 (68.8%,and 77 (70.6% ESBL positive isolates, respectively. Forty (36.6% isolateshave all three genes, while 68 (62.3% include blaTEM and blaSHV genes.Moreover, 61 (55.9% isolates carry blaCTX-M and blaTEM genes, and 54(49.5%have blactx-M and blashv.Conclusion: Regarding the high frequency of resistance to the thirdgeneration cephalosporin antibiotics, precise antibiogram testing is highlyrecommended before any antibiotic prescription in cases of infections withESBL producing microorganisms.Key words: ESBL; Escherichia coli; blaCTX-M; blaTEM; blaSHV

  11. Carbapenem-resistant Pseudomonas aeruginosa strains from a Spanish hospital: characterization of metallo-beta-lactamases, porin OprD and integrons.

    Science.gov (United States)

    Rojo-Bezares, Beatriz; Estepa, Vanesa; Cebollada, Rocío; de Toro, María; Somalo, Sergio; Seral, Cristina; Castillo, Francisco Javier; Torres, Carmen; Sáenz, Yolanda

    2014-05-01

    Molecular typing and mechanisms of carbapenem resistance such as alterations in porin OprD and presence of metallo-beta-lactamases (MBLs), as well as integrons have been studied in a collection of carbapenem-resistant Pseudomonas aeruginosa (CRPA) isolates from a Spanish hospital. One hundred and twenty-three CRPA isolates were recovered from different samples of 80 patients. Clonal relationship among CRPA was analyzed by SpeI-PFGE. Susceptibility testing to 11 antibiotics and MBL phenotype was determined by microdilution, IP/IPI E-test and double disc method. The oprD gene was studied by PCR and sequencing, and mutations were determined comparing with P. aeruginosa PAO1 sequence. Characterization of MBLs, and class 1 and 2 integrons were studied by PCR and sequencing. SDS-PAGE analysis of outer membrane proteins of selected strains was performed. Seventy-four-per-cent of patients with CRPA were hospitalised in the ICU setting and 50% had long hospitalization stays. Sixty-four different PFGE patterns were detected, and 87 CRPA strains were further analyzed. MBL phenotype was detected in 43 of 87 strains (49.4%), which contained blaVIM-2 gene inside class 1 integrons. VIM-2-producing strains belonged to lineages ST175, ST235, and ST973. A great diversity of nucleotide insertions, deletions, and mutations in oprD gene, and the presence of a new insertion sequence (ISPa45) truncating oprD were identified among CRPA strains. Class 1 integrons were detected in 75% of CRPA strains, blaVIM-2 and the new arrangement aac(3)-Ia+ISPa34+aadA1 (named as In661) being the most frequent gene-cassette arrays detected. Other gene cassettes detected in integrons were: aadB, aadA6, aadA7, aac(6')-Ib', and blaOXA-46.

  12. Complete Genome Sequence of KPC-Producing Klebsiella pneumoniae Strain CAV1193.

    Science.gov (United States)

    Sheppard, Anna E; Stoesser, Nicole; Sebra, Robert; Kasarskis, Andrew; Deikus, Gintaras; Anson, Luke; Walker, A Sarah; Peto, Tim E; Crook, Derrick W; Mathers, Amy J

    2016-01-28

    Carbapenem resistance in Klebsiella pneumoniae, frequently conferred by the blaKPC gene, is a major public health threat. We sequenced a blaKPC-containing strain of K. pneumoniae belonging to the emergent lineage ST941, in order to better understand the evolution of blaKPC within this species.

  13. Correlation between biofilm formation and resistance toward different commonly used antibiotics along with extended spectrum beta lactamase production in uropathogenic Escherichia coli isolated from the patients suspected of urinary tract infections visiting Shree Birendra Hospital, Chhauni, Kathmandu, Nepal

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    Sanjeev Neupane

    2016-02-01

    Full Text Available Abstract Background Escherichia coli is the most predominant causative agent of urinary tract infection (UTI. Recently, increase in drug resistance among the uropathogenic bacteria has caused great problem in treatment of UTI. The main objective of this research is to determine the correlation between biofilm formation and resistance toward different commonly used antibiotics along with extended spectrum beta lactamase production in uropathogenic Escherichia coli. Methods The urine samples collected from the patients suspected of urinary tract infections (visiting Shree Birendra Hospital, Chhauni, Kathmandu, Nepal between July to December 2013 were cultured in cystine lactose electrolyte deficient (CLED agar by using semi quantitative culture technique. Extended spectrum beta lactamase (ESBL production was detected by combined disc diffusion technique and biofilm formation was detected by Congo red agar method. Chi-square test was applied and p-value < 0.05 was considered statistically significant. Results Out of 1480 urine samples, E. Coli was isolated from 208 (14.1 % samples. Of total 69 (33.2 % ESBL producing uropathogenic strains of E. coli, 20 (29 % were strong biofilm producers, 22 (31.9 % were moderate biofilm producers, 11 (15.9 % were weak biofilm producers and 16 (23.2 % were biofilm non producers. Whereas among 139 ESBL non producing E. coli, 22 (15.8 % were strong biofilm producers, 20 (14.4 % were moderate biofilm producers, 13 (9.4 % were weak biofilm producers and 84 (60.4 % were biofilm non producers. Among total 108 biofilm producing E. coli, maximum resistance was observed toward cephalexin followed by amoxicillin and highest susceptibility was seen toward amikacin. Conclusion The ability of biofilm formation was found to be significantly higher in ESBL producing strains of E. coli than that in ESBL non producing strains (p < 0.05. There was higher resistance rate to antimicrobial agents among biofilm

  14. Colistin resistance in KPC-producing Klebsiella pneumoniae strains from a high specialization rehabilitation facility

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    Roberta Migliavacca

    2012-03-01

    Full Text Available The worldwide rapid spread of KPC carbapenemase-producing Klebsiella pneumoniae (KPC-Kp represents an increasing problem in clinical settings. Reports on KPC-Kp epidemic spread in Italian hospitals began to appear since 2010; colistin (COL represents one of the few remaining therapeutic options available for the treatment of such multi drug-resistant (MDR pathogens. Here we report the presence and diffusion of COL resistant KPC-Kp isolates from a High Specialization Rehabilitation Facility located in Northern Italy. Species identification and antimicrobial susceptibilities were obtained by NBC46/NM40 Microscan panels (Siemens; imipenem, meropenem and ertapenem MICs were also evaluated by Etest and broth microdilution method; blaKPC-like genes PCR were performed. PFGE (XbaI was used to investigate clonal relatedness; epidemiological data were collected from the hospital database. Seventy-five carbapenem-resistant K. pneumoniae isolates were collected from the Fondazione S. Maugeri hospital during the period January-June 2011. Seven out of 75 MDR KPC-Kp isolates by Microscan System showed COL resistance (MIC >2 mg/L. Among them, 5/7 were collected from coma and 2/7 from cardiology and rehabilitation cardiology wards. Most of these strains were from urine (5/7; the remaining 2/7 were from blood and bronco-alveolar lavage. The 85.7% of the strains showed susceptibility to tigecycline and fosfomycin; 71.4% only to gentamicina, 28.5% to trimethoprim/sulfamethoxazole and 14.2% to amikacin. The PFGE profiles obtained analyzing 5/7 isolates from patients hospitalized from almost 10 days, showed clonal relatedness between 4/5 isolates, thus confirming the high epidemic potential of almost one KPC-Kp clinical strain collected from 4 different wards.The emergence of COL resistance in KPC-Kp, dramatically reduces the available therapeutic options. These results underline the ability of a COL resistant KPC-producing clone to rapidly spread within this

  15. Ventilator-associated pneumonia caused by colistin-resistant KPC-producing Klebsiella pneumoniae: a case report and literature review.

    Science.gov (United States)

    Viaggi, Bruno; Sbrana, Francesco; Malacarne, Paolo; Tascini, Carlo

    2015-05-01

    Klebsiella pneumoniae producing KPC-type carbapenemase causes severe nosocomial infection at a high mortality rate. Nosocomial pneumonia in particular is associated with high mortality, likely due to the unfavorable pulmonary pharmacokinetics of the antibiotics used against this agent. Therefore, early and accurate microbiological identification and susceptibility evaluation are crucial in order to optimize antibiotic therapy. We report a case of ventilator-associated pneumonia caused by colistin-resistant K. pneumoniae producing KPC-type carbapenemase treated using a carbapenem-sparing therapy and tailored according to the serum procalcitonin concentration in order to limit the duration of antibiotic therapy.

  16. Phenotypic and genotypic characterization of Klebsiella pneumoniae strains with reduced susceptibiliy to carbapenems

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    Simone Ambretti

    2009-12-01

    Full Text Available Reduced susceptibility to carbapenems in Gram-negative pathogens is an emerging feature of the antibiotic-resistance phenomenom Reports about strains resistant to this class of antibiotics among Enterobacteriaceae, particularly in Klebsiella pneumoniae, are increasing.The aims of this study were to assess the incidence of Klebsiella pneumoniae with reduced susceptibility to carbapenems in Bologna area and to carry out the characterization of these strains.The study included isolates of K. pneumoniae that showed reduced susceptibility to carbapenems, as detected by an automated system (Vitek2, bioMérieux. Between January and May 2009, 26 strains were collected (mainly isolated from urinary samples.These isolates were tested for susceptibility to carbapenems by E-test, to define MIC values for meropenem and ertapenem. Moreover, to detect the production of metallo-beta lactamases (MBL and carbapenemases (KPC were respectively performed the Etest with imipenem and imipenem/EDTA (IPM-IPM/EDTA and the modified Hodge test. Susceptibility assays performed by E-test showed that 25/26 strains were susceptible to meropenem, while for ertapenem 20/26 strains resulted resistant.The modified Hodge test was positive for 1 strain, while all the isolates were negative to the IPM-IPM/EDTA E-test.These results show that, as recently reported, the majority of strains of K. pneumoniae exhibiting reduced susceptibility to carbapenems, especially to ertapenem, are characterized by the production of ESBLs, which likely is associated with the loss of porins. On the other side, one strain was found to produce KPC and this finding confirms that the diffusion of carbapenemases producing K. pneumoniae has also to be considered in this geographic area.

  17. Structural Milestones in the Reaction Pathway of an Amide Hydrolase: Substrate, Acyl, and Product Complexes of Cephalothin with AmpC [beta]-Lactamase

    Energy Technology Data Exchange (ETDEWEB)

    Beadle, Beth M.; Trehan, Indi; Focia, Pamela J.; Shoichet, Brian K. (NWU)

    2010-03-05

    {beta}-lactamases hydrolyze {beta}-lactam antibiotics and are the leading cause of bacterial resistance to these drugs. Although {beta}-lactamases have been extensively studied, structures of the substrate-enzyme and product-enzyme complexes have proven elusive. Here, the structure of a mutant AmpC in complex with the {beta}-lactam cephalothin in its substrate and product forms was determined by X-ray crystallography to 1.53 {angstrom} resolution. The acyl-enzyme intermediate between AmpC and cephalothin was determined to 2.06 {angstrom} resolution. The ligand undergoes a dramatic conformational change as the reaction progresses, with the characteristic six-membered dihydrothiazine ring of cephalothin rotating by 109{sup o}. These structures correspond to all three intermediates along the reaction path and provide insight into substrate recognition, catalysis, and product expulsion.

  18. Salicylate decreases production of AmpC type beta-lactamases and increases susceptibility to beta-lactams in a Morganella morganii clinical isolate.

    Science.gov (United States)

    Tavío, María M; Perilli, Mariagrazia; Vila, Jordi; Becerro, Pino; Casañas, Lucía; Amicosante, Gianfranco; Jiménez de Anta, María Teresa

    2004-09-01

    The effect of salicylate, a marRAB inducer, on the resistance to beta-lactams was characterized in an AmpC beta-lactamase hyperproducer Morganella morganii clinical isolate (the M1 strain). Results were compared with those of the effect of salicylate in a wild-type M. morganii strain. Salicylate induced a decreased susceptibility to nalidixic acid, norfloxacin and tetracycline and simultaneously increased the susceptibility to beta-lactams apparently due to the repression of AmpC beta-lactamase synthesis in the M1 strain. Likewise, salicylate only repressed 46 kDa outer membrane protein expression in the wild-type strain, since the clinical isolate M1 did not express it.

  19. Multifocal diffusion of KPC-3-producing ST512 Klebsiella pneumoniae in Italy

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    Aurora Piazza

    2012-03-01

    Full Text Available Introduction. The dissemination of carbapenemase-producing Klebsiella pneumoniae strains is an increasing problem worldwide. KPC ß-lactamases are Ambler class A enzymes mostly plasmid-encoded; their global spread represents a threat to clinical patients care and public health. Multi locus sequence type (ST258 is currently the most spread K. pneumoniae clone associated with KPC enzymes. Here we report the first identification and multifocal spread of KPC-3 producing K. pneumoniae clinical strains belonging to ST512 in Italy. Materials and Methods. Fifty six carbapenem-resistant K. pneumoniae isolates were collected from 7 Italian hospitals during the period June 2009-May 2011. Isolates were obtained from different wards (spinal unit, medicine, hematology, etc. and biological samples (mostly rectal swabs, urine and blood. Species identification and antimicrobial susceptibilities were obtained by NBC46/NM40 Microscan panels (Siemens. MICs values were interpreted according to EUCAST 2011 breakpoints. Modified Hodge test and combined disk test with phenyl-boronic acid (BOR and EDTA were performed.The presence of blaKPC genes were confirmed by PCR and sequencing. A complete characterization of the produced ß-lactamases (BLs was obtained by IEF followed by PCR experiments using primers specific for the detection of blaCTX-M-, blaTEM- and blaSHV type genes. PFGE and multilocus sequence typing (MLST were both used to investigate clonal isolates relatedness. Results. All 56 isolates resulted positive for the presence of KPC-type carbapenemases by both phenotypical and molecular analysis. Fifteen isolates, chosen as representative, were further investigated. Ten out of 15 isolates harboring the blaKPC-2 gene clustered with the known ST258, while the remaining 5/10 belonged to the newly described ST512 and harbored the blaKPC-3 gene. ST512 isolates, from 3/7 hospitals, were collected from rectal swabs (40%, blood (20%, endotracheal aspirate (20% and

  20. Outbreak of OXA-48-Producing Klebsiella pneumoniae Involving a Sequence Type 101 Clone in Batna University Hospital, Algeria.

    Science.gov (United States)

    Loucif, Lotfi; Kassah-Laouar, Ahmed; Saidi, Mahdia; Messala, Amina; Chelaghma, Widad; Rolain, Jean-Marc

    2016-12-01

    Seven nonredundant ertapenem-resistant Klebsiella pneumoniae isolates were collected between May 2014 and 19 January 2015 in the nephrology and hematology units of Batna University Hospital in Algeria. All strains coproduced the blaOXA-48, blaCTX-M-15, blaSHV-1, and blaTEM-1D genes. Six of these isolates belonged to the pandemic clone sequence type 101 (ST101). The blaOXA-48 gene was located on a conjugative IncL/M-type plasmid. This is the first known outbreak of OXA-48-producing K. pneumoniae isolates involving an ST101 clone in Batna University Hospital.

  1. Monitoring and characterization of extended-spectrum beta-lactamases in Escherichia coli strains from healthy and sick animals in Spain in 2003.

    Science.gov (United States)

    Briñas, Laura; Moreno, Miguel Angel; Teshager, Tirushet; Sáenz, Yolanda; Porrero, María Concepción; Domínguez, Lucas; Torres, Carmen

    2005-03-01

    Genes encoding CTX-M-14, CTX-M-9, CTX-M-1, CTX-M-32, SHV-12, TEM-52, or CMY-2 beta-lactamases were detected in 21 Escherichia coli strains recovered during 2003 from sick animals (11 of 459 [2.4%] strains) and healthy animals (10 of 158 [6.3%] strains) in Spain. Twelve of these strains harbored bla(CTX-M) genes and showed unrelated pulsed-field gel electrophoresis patterns.

  2. Development of SYN-004, an oral beta-lactamase treatment to protect the gut microbiome from antibiotic-mediated damage and prevent Clostridium difficile infection.

    Science.gov (United States)

    Kaleko, Michael; Bristol, J Andrew; Hubert, Steven; Parsley, Todd; Widmer, Giovanni; Tzipori, Saul; Subramanian, Poorani; Hasan, Nur; Koski, Perrti; Kokai-Kun, John; Sliman, Joseph; Jones, Annie; Connelly, Sheila

    2016-10-01

    The gut microbiome, composed of the microflora that inhabit the gastrointestinal tract and their genomes, make up a complex ecosystem that can be disrupted by antibiotic use. The ensuing dysbiosis is conducive to the emergence of opportunistic pathogens such as Clostridium difficile. A novel approach to protect the microbiome from antibiotic-mediated dysbiosis is the use of beta-lactamase enzymes to degrade residual antibiotics in the gastrointestinal tract before the microflora are harmed. Here we present the preclinical development and early clinical studies of the beta-lactamase enzymes, P3A, currently referred to as SYN-004, and its precursor, P1A. Both P1A and SYN-004 were designed as orally-delivered, non-systemically available therapeutics for use with intravenous beta-lactam antibiotics. SYN-004 was engineered from P1A, a beta-lactamase isolated from Bacillus licheniformis, to broaden its antibiotic degradation profile. SYN-004 efficiently hydrolyses penicillins and cephalosporins, the most widely used IV beta-lactam antibiotics. In animal studies, SYN-004 degraded ceftriaxone in the GI tract of dogs and protected the microbiome of pigs from ceftriaxone-induced changes. Phase I clinical studies demonstrated SYN-004 safety and tolerability. Phase 2 studies are in progress to assess the utility of SYN-004 for the prevention of antibiotic-associated diarrhea and Clostridium difficile disease.

  3. Phenotypic and genotypic evaluation of beta-lactamases (ESBL and KPC) among enterobacteria isolated from community-acquired monomicrobial urinary tract infections.

    Science.gov (United States)

    Dias, Vanessa Cordeiro; da Silva, Vânia Lúcia; Barros, Renata; Bastos, André Netto; de Andrade Bastos, Lucas Quinnet; de Andrade Bastos, Victor Quinnet; Diniz, Cláudio Galuppo

    2014-12-01

    Beta-lactamases enzymes such as extended-spectrum beta-lactamases (ESBL) and carbapenemase type beta-lactamases (KPC) confer resistance to beta-lactam drugs among Gram-negative rods, mainly Enterobacteriaceae, as those frequently related to urinary tract infections (UTI). The aim of this study was to evaluate ESBL and KPC among enterobacteria isolated from monomicrobial UTI and to establish correlations between the presence of genetic markers and the phenotypic resistance to beta-lactam antibiotics. Out of 12 304 urine samples collected during 2009, 93 enterobacteria showing an ESBL phenotype were recovered. Imipenem was used for KPC screening and modified disk approximation assay was used for detection of ESBL phenotype. Polymerase chain reaction was used for screening of bla(SHV), bla(TEM), bla(CTX-M), and bla(KPC). Considering the isolated bacteria showing ESBL phenotype 56% of the isolates were positive for two genes. The bla(TEM) was the most frequent (87·1%). Neither KPC phenotype nor bla(KPC)-harboring bacteria were observed. Monitoring the antimicrobial resistance is extremely important to sustain empirical therapy of community-acquired urinary tract infections (Co-UTI).

  4. Characteristics of KPC-2-producing Klebsiella pneumoniae (ST258) clinical isolates from outbreaks in 2 Mexican medical centers.

    Science.gov (United States)

    Garza-Ramos, Ulises; Barrios, Humberto; Reyna-Flores, Fernando; Sánchez-Pérez, Alejandro; Tamayo-Legorreta, Elsa; Ibarra-Pacheco, Alvaro; Salazar-Salinas, Juana; Núñez-Ceballos, Ricardo; Silva-Sanchez, Jesus

    2014-08-01

    The KPC-producing Klebsiella pneumoniae sequence type 258 (ST258) is an important pathogen widely spread in nosocomial infections. In this study, we identified the KPC-2-producing K. pneumoniae clinical isolates of 2 unrelated outbreaks that corresponded to pandemic strain ST258. The isolates showed high resistance to cephalosporins, carbapenems, quinolones, and colistin. The KPC-2-producing K. pneumoniae isolates were compared to the previously studied KPC-3-producing K. pneumoniae isolates from an outbreak in Mexico; they showed an unrelated pulsed-field gel electrophoresis fingerprinting pattern and a different plasmid profile. The KPC-2 carbapenemase gene was identified in two 230- and 270-kb non-conjugative plasmids; however, 1 isolate transferred the KPC-2 gene onto an 80-kb plasmid. These findings endorse the need of carrying out a continuous molecular epidemiological surveillance of carbapenem-resistant isolates in hospitals in Mexico.

  5. First Report of Chronic Pulmonary Infection by KPC-3-Producing and Colistin-Resistant Klebsiella pneumoniae Sequence Type 258 (ST258) in an Adult Patient with Cystic Fibrosis

    Science.gov (United States)

    Delfino, Emanuele; Del Bono, Valerio; Coppo, Erika; Marchese, Anna; Manno, Graziana; Morelli, Patrizia; Minicucci, Laura; Viscoli, Claudio

    2015-01-01

    The spread of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae continues to increase, and the possible development of KPC-producing K. pneumoniae infections in cystic fibrosis (CF) patients is a matter of concern. Here, we describe the establishment of a chronic lung infection due to a colistin-resistant KPC-producing K. pneumoniae isolate in an Italian CF patient. PMID:25653395

  6. Population Structure of KPC-Producing Klebsiella pneumoniae Isolates from Midwestern U.S. Hospitals

    Science.gov (United States)

    Wright, Meredith S.; Perez, Federico; Brinkac, Lauren; Jacobs, Michael R.; Kaye, Keith; Cober, Eric; van Duin, David; Marshall, Steven H.; Hujer, Andrea M.; Rudin, Susan D.; Hujer, Kristine M.

    2014-01-01

    Genome sequencing of carbapenem-resistant Klebsiella pneumoniae isolates from regional U.S. hospitals was used to characterize strain diversity and the blaKPC genetic context. A phylogeny based on core single-nucleotide variants (SNVs) supports a division of sequence type 258 (ST258) into two distinct groups. The primary differences between the groups are in the capsular polysaccharide locus (cps) and their plasmid contents. A strict association between clade and KPC variant was found. The blaKPC gene was found on variants of two plasmid backbones. This study indicates that highly similar K. pneumoniae subpopulations coexist within the same hospitals over time. PMID:24913165

  7. Drug resistance analysis of klebsiella pneumoniae pneumonia subspecies%肺炎克雷伯菌肺炎亚种的耐药性分析

    Institute of Scientific and Technical Information of China (English)

    陈名霞; 张鑫; 许立新

    2014-01-01

    commonly used antibiotics was high, but for imipenem, amikacin, cefepime, cefoperazone/sulbactam, piperacillin/tazobactam, and minocyline was low. so it can be used as clinical use of drugs. Among 108 strains klebsiella pneumoniae pneumonia subspecies, 34 cases were identified to produce extended spectrum beta-lactamase (ESBLs) (31.5%). Among 12 strains klebsiella pneumoniae pneumonia subspecies that were resistant to imipenem, KPC positive were 9 cases (75%).Conclusions:Drug resistance rate of Klebsiella pneumoniae pneumonia subspecies was high. So strengthening drug test and clinical medication according to the