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Sample records for antimicrobial susceptibility testing

  1. Next-Generation Antimicrobial Susceptibility Testing

    OpenAIRE

    Belkum, Alex van; Dunne, W. Michael

    2013-01-01

    Antimicrobial resistance has emerged as one of the most-significant health care problems of the new millennium, and the clinical microbiology laboratory plays a central role in optimizing the therapeutic management of patients with infection. This minireview explores the potential value of innovative methods for antimicrobial susceptibility testing of microorganisms that could provide valuable alternatives to existing methodologies in the very near future.

  2. Real-Time Optical Antimicrobial Susceptibility Testing

    DEFF Research Database (Denmark)

    Fredborg, Marlene; Andersen, Klaus R; Jørgensen, Erik;

    2013-01-01

    Rapid antibiotic susceptibility testing is in highly demand in health-care fields as antimicrobial resistant bacterial strains emerge and spread. Here we describe an optical screening system (oCelloScope), which based on time-lapse imaging of 96 bacteria-antibiotic combinations at a time......, introduces real-time detection of bacterial growth and antimicrobial susceptibility, with imaging material to support the automatically generated graphs. Automated antibiotic susceptibility tests of a monoculture showed statistically significant antibiotic effect within 6 minutes and within 30 minutes in...... complex samples from pigs suffering from catheter associated urinary tract infections. The oCelloScope system provides a fast high-throughput screening method to detect bacterial susceptibility that may entail earlier diagnosis and introduction of appropriate targeted therapy and thus combat the threat...

  3. [Internal quality control for antimicrobial susceptibility test: an experience feedback].

    Science.gov (United States)

    Vedy, Serge

    2012-01-01

    Internal quality control (IQC) position in antimicrobial susceptibility testing must be evaluated attentively before using. Ours S. aureus ATCC 25923 use during year 2011 has given precious information that can be useful for other laboratories. First, IQC should never be used before checking that all the realisation process steps are controlled. It will then appear that reagents are the most susceptible to give false results. That's what happens in 2.74% of antimicrobial susceptibility test. IQC is then useful to limit their clinical's impact. However, IQC use also shows that quality improvement will be difficult without industrial producer's involvement. PMID:22826843

  4. Susceptibility Testing

    Science.gov (United States)

    ... page helpful? Also known as: Sensitivity Testing; Drug Resistance Testing; Culture and Sensitivity; C & S; Antimicrobial Susceptibility Formal name: Bacterial and Fungal Susceptibility Testing Related tests: Urine Culture ; ...

  5. High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila.

    Science.gov (United States)

    Chiaraviglio, Lucius; Kirby, James E

    2015-12-01

    Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

  6. High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila

    Science.gov (United States)

    Chiaraviglio, Lucius

    2015-01-01

    Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

  7. [Antimicrobial susceptibility testing of anaerobic bacteria].

    Science.gov (United States)

    García-Sánchez, José E; García-Sánchez, Enrique; García-García, María Inmaculada

    2014-02-01

    The anaerobic bacteria resistance to antibiotics is increasing, and even has appeared against the most active of those, like metronidazol and carbapenems. This fact forces to make and periodical sensibility tests -at least in the most aggressive and virulent species, in cases that they are isolated from life locations and in the absence of therapeutic response- to check the local sensibility and to establish suitable empiric therapies, all based on multicentric studies carried out in order to this or well to check the activity of new antibiotics. For the laboratory routine, the easiest sensibility method is the E-test/MIC evaluator. Another alternative is microdilution, that's only normalized for Bacteroides. There are preliminary facts that allow the use of disc diffusion method in some species of Bacteroides and Clostridium. For the temporal and multicentric studies, the procedure is dilution in agar plate, the reference method. PMID:24630580

  8. Antimicrobial susceptibility testing of less commonly isolated Haemophilus species using Haemophilus test medium.

    OpenAIRE

    Jorgensen, J H; Howell, A W; Maher, L A

    1990-01-01

    Haemophilus test medium (HTM) was developed recently for dilution and disk diffusion antimicrobial agent susceptibility testing of Haemophilus influenzae. The application of HTM to the testing of other, less frequently encountered Haemophilus species recovered from humans was evaluated in this study by using commercially prepared HTM (BBL Microbiology Systems, Cockeysville, Md.) in broth microdilution and agar disk diffusion susceptibility tests with 18 antimicrobial agents. A total of 93.3% ...

  9. 21 CFR 866.1700 - Culture medium for antimicrobial susceptibility tests.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Culture medium for antimicrobial susceptibility tests. 866.1700 Section 866.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND....1700 Culture medium for antimicrobial susceptibility tests. (a) Identification. A culture medium...

  10. Antimicrobial Susceptibility Testing of Acinetobacter spp. by NCCLS Broth Microdilution and Disk Diffusion Methods

    OpenAIRE

    Swenson, Jana M.; Killgore, George E.; Tenover, Fred C.

    2004-01-01

    Although both broth microdilution (BMD) and disk diffusion (DD) are listed by NCCLS as acceptable methods for testing Acinetobacter spp. for antimicrobial susceptibility, few studies have compared the results generated by the two methods. We tested 196 isolates of Acinetobacter spp. from nine U.S. hospitals and from the Centers for Disease Control culture collection by using BMD and DD and clinically appropriate antimicrobial agents. Categorical results for amikacin, ciprofloxacin, gatifloxac...

  11. Antimicrobial Disk Susceptibility Testing of Leptospira spp. Using Leptospira Vanaporn Wuthiekanun (LVW) Agar

    OpenAIRE

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Langla, Sayan; White, Nicholas J; Day, Nicholas P. J.; Limmathurotsakul, Direk; Peacock, Sharon J.

    2015-01-01

    Leptospira Vanaporn Wuthiekanun (LVW) agar was used to develop a disk diffusion assay for Leptospira spp. Ten pathogenic Leptospira isolates were tested, all of which were susceptible to 17 antimicrobial agents (amoxicillin/clavulanic acid, amoxicillin, azithromycin, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, doripenem, doxycycline, gentamicin, linezolid, nitrofurantoin, penicillin, piperacillin/tazobactam, and tetracycline). All 10 isolates had no zone ...

  12. Bacterial Cytological Profiling (BCP as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    D.T. Quach

    2016-02-01

    Full Text Available Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP, which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA and -resistant (MRSA clinical isolates of S. aureus (n = 71 within 1–2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS from daptomycin non-susceptible (DNS S. aureus strains (n = 20 within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice.

  13. Bacterial Cytological Profiling (BCP) as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus.

    Science.gov (United States)

    Quach, D T; Sakoulas, G; Nizet, V; Pogliano, J; Pogliano, K

    2016-02-01

    Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP), which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA) and -resistant (MRSA) clinical isolates of S. aureus (n = 71) within 1-2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS) from daptomycin non-susceptible (DNS) S. aureus strains (n = 20) within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice. PMID:26981574

  14. Antimicrobial susceptibility testing of Clostridium difficile using EUCAST epidemiological cut-off values and disk diffusion correlates

    DEFF Research Database (Denmark)

    Erikstrup, L T; Hall, Vanessa Jane; Kahlmeter, G;

    2012-01-01

    Clin Microbiol Infect ABSTRACT: With the emergence of reduced susceptibility of Clostridium difficile to metronidazole and vancomycin the value of antimicrobial susceptibility testing has increased. The aim of our study was to evaluate disk diffusion for susceptibility testing of C. difficile by ...

  15. A rapid antimicrobial susceptibility test based on single-cell morphological analysis.

    Science.gov (United States)

    Choi, Jungil; Yoo, Jungheon; Lee, Mincheol; Kim, Eun-Geun; Lee, Ji Soo; Lee, Seungok; Joo, Seik; Song, Sang Hoon; Kim, Eui-Chong; Lee, Jung Chan; Kim, Hee Chan; Jung, Yong-Gyun; Kwon, Sunghoon

    2014-12-17

    A rapid antibiotic susceptibility test (AST) is desperately needed in clinical settings for fast and appropriate antibiotic administration. Traditional ASTs, which rely on cell culture, are not suitable for urgent cases of bacterial infection and antibiotic resistance owing to their relatively long test times. We describe a novel AST called single-cell morphological analysis (SCMA) that can determine antimicrobial susceptibility by automatically analyzing and categorizing morphological changes in single bacterial cells under various antimicrobial conditions. The SCMA was tested with four Clinical and Laboratory Standards Institute standard bacterial strains and 189 clinical samples, including extended-spectrum β-lactamase-positive Escherichia coli and Klebsiella pneumoniae, imipenem-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococci from hospitals. The results were compared with the gold standard broth microdilution test. The SCMA results were obtained in less than 4 hours, with 91.5% categorical agreement and 6.51% minor, 2.56% major, and 1.49% very major discrepancies. Thus, SCMA provides rapid and accurate antimicrobial susceptibility data that satisfy the recommended performance of the U.S. Food and Drug Administration. PMID:25520395

  16. Assessment of Etest as an Alternative to Agar Dilution for Antimicrobial Susceptibility Testing of Neisseria gonorrhoeae

    OpenAIRE

    Liu, Hsi; Taylor, Thomas H.; Pettus, Kevin; Trees, David

    2014-01-01

    We studied whether the Etest can be used as an alternative to agar dilution to determine antimicrobial susceptibilities of ceftriaxone, cefixime, and cefpodoxime in Neisseria gonorrhoeae surveillance. One hundred fifteen clinical and laboratory isolates of N. gonorrhoeae were tested following the Clinical Laboratory Improvement Amendments (CLIA)-approved CLSI standard agar dilution method and, separately, by the Etest according to the manufacturer's recommendations. The MICs were determined a...

  17. Harmonization of antimicrobial susceptibility testing among veterinary diagnostic laboratories in the five Nordic countries

    DEFF Research Database (Denmark)

    Petersen, A.; Aarestrup, Frank Møller; Hofshagen, Merete; Sipila, H.; Franklin, A.; Gunnarsson, E.

    2003-01-01

    A total of 100 bacterial strains (25 Escherichia coli, 25 Salmonella enterica, 25 Staphylococcus aureus, and 25 Enterococcus strains) and four reference strains were tested for susceptibility toward 8-12 antimicrobial agents in 12 veterinary diagnostic laboratories in the five Nordic countries......, whereas for Enterococcus spp., two laboratories had less than 90 % concordant results. Susceptibility testing of Salmonella to fluoroquinolones gave rise to almost 0.5% nonconcordant results and susceptibility testing of S. aureus to vancomycin resulted in that 1.8% of the strains were incorrectly...... reported as vancomycin resistant. Ten laboratories identified the Enterococcus spp. to species level. All five Enterococcus faecium and 10 Enterococcus faecalis selected from the strain collection at the Danish Veterinary Institute were correctly identified by all laboratories, whereas some problems were...

  18. Antimicrobial Susceptibility Testing for Escherichia coli Strains to Fluoroquinolones, in Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    FA Nakhjavani

    2007-05-01

    Full Text Available Background: Urinary Tract Infections (UTIs are one of the most common infectious diseases diagnosed all over the world. Meanwhile most episode of UTIs are caused by Escherichia coli (up to 85% and frequently fluoroquinolones are preferred as initial agents for empiric therapy of UTIs. Widespread use of fluoroquinolones has resulted in an increasing incidence of resistance these agents all over the world. The aim of this study was to assess, susceptibility of Escherichia coli strains from UTI patients against common fluoroquinolones. Methods: Antimicrobial susceptibility testing was determined by disk agar diffusion (DAD and Minimal Inhibitory Concentration methods as described by the National Committee for Clinical Laboratory Standards (NCCLS. Results: One hundred sixty four clinical isolates of E. coli were collected by urine cultures from patients with UTI. The extent of resistant to nalidixic acid, ofloxacin, norfloxacin and ciprofloxacin, by disk diffusion method was 49.3%, 44.5%, 41.4% and 40.2%, respectively. Resistance to ciprofloxacin by MIC method was 4.9%. Conclusion: This study represents high level resistant of E. coli isolates from UTI patients. It is because of inappropriate and incorrect administration of antimicrobial agents in blind cases. This problem remarks significance of performing antimicrobial susceptibility testing before empiric antibiotic therapy. To overcome this problem use of unnecessary antibiotics therapy should be limited.

  19. Routine disc diffusion antimicrobial susceptibility testing of Clostridium difficile and association with PCR ribotype 027

    DEFF Research Database (Denmark)

    Holt, H M; Danielsen, T K; Justesen, U S

    2015-01-01

    Reduced susceptibility to metronidazole and vancomycin in Clostridium difficile has been reported, which emphasises the need for simple antimicrobial susceptibility testing methods. The aim of this study was to apply a published disc diffusion method and zone diameter breakpoint correlates to the...... published breakpoint (<23 mm) and five isolates had a vancomycin zone diameter below the published breakpoint (<19 mm), most of which were polymerase chain reaction (PCR) ribotype 027. The total number of PCR ribotype 027 was 29 (1.1 %). Overall, C. difficile PCR ribotype 027 isolates had smaller zone...... diameters than non-027 isolates. The disc diffusion method is very simple and inexpensive, and the published zone diameter breakpoints will detect C. difficile isolates with reduced susceptibility to metronidazole and vancomycin....

  20. Rapid antimicrobial susceptibility testing of clinical isolates by digital time-lapse microscopy.

    Science.gov (United States)

    Fredborg, M; Rosenvinge, F S; Spillum, E; Kroghsbo, S; Wang, M; Sondergaard, T E

    2015-12-01

    Rapid antimicrobial susceptibility testing (AST) is essential for early and appropriate therapy. Methods with short detection time enabling same-day treatment optimisation are highly favourable. In this study, we evaluated the potential of a digital time-lapse microscope system, the oCelloScope system, to perform rapid AST. The oCelloScope system demonstrated a very high accuracy (96% overall agreement) when determining the resistance profiles of four reference strains, nine clinical isolates, including multi-drug-resistant isolates, and three positive blood cultures. AST of clinical isolates (168 antimicrobial agent-organism combinations) demonstrated 3.6% minor, no major and 1.2% very major errors of the oCelloScope system compared to conventional susceptibility testing, as well as a rapid and correct phenotypic detection of strains with methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL) profiles. The net average time-to-result was 108 min, with 95% of the results being available within 180 min. In conclusion, this study strongly indicates that the oCelloScope system holds considerable potential as an accurate and sensitive AST method with short time-to-result, enabling same-day targeted antimicrobial therapy, facilitating antibiotic stewardship and better patient management. A full-scale validation of the oCelloScope system including more isolates is necessary to assess the impact of using it for AST. PMID:26407621

  1. Harmonization of antimicrobial susceptibility testing among veterinary diagnostic laboratories in the five Nordic countries

    DEFF Research Database (Denmark)

    Petersen, A.; Aarestrup, Frank Møller; Hofshagen, Merete;

    2003-01-01

    A total of 100 bacterial strains (25 Escherichia coli, 25 Salmonella enterica, 25 Staphylococcus aureus, and 25 Enterococcus strains) and four reference strains were tested for susceptibility toward 8-12 antimicrobial agents in 12 veterinary diagnostic laboratories in the five Nordic countries...... using routine methodology. In addition, the 25 Enterococcus strains were identified to species level. A total of 22,598 (97.2%) out of 23,259 test results were in accordance when the data were categorized as susceptible or resistant. When the reported results were categorized according to the National...... reported as vancomycin resistant. Ten laboratories identified the Enterococcus spp. to species level. All five Enterococcus faecium and 10 Enterococcus faecalis selected from the strain collection at the Danish Veterinary Institute were correctly identified by all laboratories, whereas some problems were...

  2. Genotyping using whole-genome sequencing is a realistic alternative to surveillance based on phenotypic antimicrobial susceptibility testing

    DEFF Research Database (Denmark)

    Zankari, Ea; Hasman, Henrik; Kaas, Rolf Sommer;

    2013-01-01

    200 isolates originating from Danish pigs, covering four bacterial species. Genomic DNA was purified from all isolates and sequenced as paired-end reads on the Illumina platform. The web servers ResFinder and MLST (www.genomicepidemiology.org) were used to identify acquired antimicrobial resistance......Objectives: Antimicrobial susceptibility testing of bacterial isolates is essential for clinical diagnosis, to detect emerging problems and to guide empirical treatment. Current phenotypic procedures are sometimes associated with mistakes and may require further genetic testing. Whole......-genome sequencing (WGS) may soon be within reach even for routine surveillance and clinical diagnostics. The aim of this study was to evaluate WGS as a routine tool for surveillance of antimicrobial resistance compared with current phenotypic procedures. Methods: Antimicrobial susceptibility tests were performed on...

  3. Rapid Antimicrobial Susceptibility Testing of Bacillus anthracis, Yersinia pestis, and Burkholderia pseudomallei by Use of Laser Light Scattering Technology.

    Science.gov (United States)

    Bugrysheva, Julia V; Lascols, Christine; Sue, David; Weigel, Linda M

    2016-06-01

    Rapid methods to determine antimicrobial susceptibility would assist in the timely distribution of effective treatment or postexposure prophylaxis in the aftermath of the release of bacterial biothreat agents such as Bacillus anthracis, Yersinia pestis, or Burkholderia pseudomallei Conventional susceptibility tests require 16 to 48 h of incubation, depending on the bacterial species. We evaluated a method that is based on laser light scattering technology that measures cell density in real time. We determined that it has the ability to rapidly differentiate between growth (resistant) and no growth (susceptible) of several bacterial threat agents in the presence of clinically relevant antimicrobials. Results were available in 10 h of incubation. Use of laser scattering technology decreased the time required to determine antimicrobial susceptibility by 50% to 75% for B. anthracis, Y. pestis, and B. pseudomallei compared to conventional methods. PMID:26984973

  4. Antimicrobial susceptibilities of Clostridium difficile.

    OpenAIRE

    Shuttleworth, R; Taylor, M.; Jones, D M

    1980-01-01

    The antimicrobial susceptibilities of 78 strains of Clostridium difficile isolated from patients with and without gastrointestinal symptoms were determined and compared. Strains from patients with symptoms were more likely to show resistance to antibiotics. The antimicrobial susceptibilities of toxigenic and non-toxigenic strains were found to be similar.

  5. Comparison of Rosco Neo-Sensitabs with Oxoid paper disks in EUCAST disk diffusion antimicrobial susceptibility testing on Mueller-Hinton agar

    DEFF Research Database (Denmark)

    Justesen, U S; Acar, Ziyap; Olsson, K;

    2013-01-01

    This study compared Neo-Sensitabs with Oxoid paper disks using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) disk diffusion antimicrobial susceptibility test on Mueller-Hinton agar. The EUCAST-recommended quality control strains (Escherichia coli ATCC 25922, Pseudomonas ...

  6. In vitro antimicrobial susceptibility testing of human Brucella melitensis isolates from Qatar between 2014 - 2015

    NARCIS (Netherlands)

    Deshmukh, A.; Hagen, F.; Sharabasi, O.A.; Abraham, M.; Wilson, G.; Doiphode, S.; Maslamani, M.A.; Meis, J.F.G.M.

    2015-01-01

    BACKGROUND: Brucellosis is one of the most common zoonotic disease affecting humans and animals and is endemic in many parts of the world including the Gulf Cooperation Council region (GCC). The aim of this study was to identify the species and determine the antimicrobial susceptibility pattern of B

  7. Miniaturized Antimicrobial Susceptibility Test by Combining Concentration Gradient Generation and Rapid Cell Culturing

    Directory of Open Access Journals (Sweden)

    Samuel C. Kim

    2015-10-01

    Full Text Available Effective treatment of bacterial infection relies on timely diagnosis and proper prescription of antibiotic drugs. The antimicrobial susceptibility test (AST is one of the most crucial experimental procedures, providing the baseline information for choosing effective antibiotic agents and their dosages. Conventional methods, however, require long incubation times or significant instrumentation costs to obtain test results. We propose a lab-on-a-chip approach to perform AST in a simple, economic, and rapid manner. Our assay platform miniaturizes the standard broth microdilution method on a microfluidic device (20 × 20 mm that generates an antibiotic concentration gradient and delivers antibiotic-containing culture media to eight 30-nL chambers for cell culture. When tested with 20 μL samples of a model bacterial strain (E. coli ATCC 25922 treated with ampicillin or streptomycin, our method allows for the determination of minimum inhibitory concentrations consistent with the microdilution test in three hours, which is almost a factor of ten more rapid than the standard method.

  8. Contributions of culture and antimicrobial susceptibility tests to the retreatment of patients with pulmonary tuberculosis

    Directory of Open Access Journals (Sweden)

    Bruno Horta Andrade

    2013-08-01

    Full Text Available Introduction This study evaluated the efficacy of retreatment of pulmonary tuberculosis (TB with regard to treatment outcomes and antimicrobial susceptibility testing (ST profiles. Methods This retrospective cohort study analyzed 144 patients treated at a referral hospital in Brazil. All of them had undergone prior treatment, were smear-positive for TB and received a standardized retreatment regimen. Fisher's 2-tailed exact test and the χ2 test were used; RRs and 95% CIs were calculated using univariate and multivariate binary logistic regression. Results The patients were cured in 84 (58.3% cases. Failure was associated with relapsed treatment and abandonment (n=34. Culture tests were obtained for 103 (71.5% cases; 70 (48.6% had positive results. ST results were available for 67 (46.5% cases; the prevalence of acquired resistance was 53.7%. There were no significant differences between those who achieved or not therapeutic success (p=0.988, despite being sensitive or resistant to 1 or more drugs. Rifampicin resistance was independently associated with therapeutic failure (OR: 4.4, 95% CI:1.12-17.37, p=0.034. For those cases in which cultures were unavailable, a 2nd model without this information was built. In this, return after abandonment was significantly associated with retreatment failure (OR: 3.59, 95% CI:1.17-11.06, p=0.026. Conclusions In this cohort, the general resistance profile appeared to have no influence on treatment outcome, except in cases of rifampicin resistance. The form of reentry was another independent predictor of failure. The use of bacterial culture identification and ST in TB management must be re-evaluated. The recommendations for different susceptibility profiles must also be improved.

  9. [The annual changes in antimicrobial susceptibility test results of Pseudomonas aeruginosa isolates from the Kinki district].

    Science.gov (United States)

    Fukuda, Saori; Komatsu, Masaru; Nakamura, Tatuya; Jikimoto, Takumi; Nishio, Hisaaki; Yamasaki, Katsutoshi; Satoh, Kaori; Toda, Hirofumi; Orita, Tamaki; Sueyoshi, Noriyuki; Kita, Machiko; Nishi, Isao; Akagi, Masahiro; Higuchi, Takeshi; Kofuku, Tomomi; Nakai, Isako; Ono, Tamotsu; Kida, Kaneyuki; Ohama, Masanobu; Watari, Hideo; Shimura, Satoshi; Niki, Makoto; Kuchibiro, Tomokazu; Wada, Yasunao

    2016-04-01

    A study was conducted of the 1,225 Pseudomonas aeruginosa strains that were isolated at 20 medical institutions in the Kinki district between 2011 and 2013 to determine their antimicrobial susceptibility and to characterize the strains of multidrug-resistant Pseudomonas aeruginosa (MDRP) and the metallo-β-lactamase (MBL) -producing strains. The MIC50/MIC90 values (μg/mL) of the various antimicrobial agents were as follows: imipenem, 2/>8; meropenem, 1/>8; doripenem, 0.5/8; biapenem, 1/>8; tazobactam/piperacillin, 8/>64; piperacillin, 8/>64; sulbactam/cefoperazone, 8/64; cefepime, 4/16; cefozopran, 2/>16; aztreonam, 8/>16; amikacin, 4/16; levofloxacin, 1/>4; and ciprofloxacin, 0.25/>2. From the viewpoint of the annual changes in the susceptibility rates (according to the CLSI guidelines [M100-S22]), the susceptibility to tazobactam/piperacillin, piperacillin, cefepime, cefozopran and aztreonam decreased in 2013. On the other hand, two antimicrobial agents showed high susceptibility rates each year; amikacin (94.0-95.6%) showed the highest rate, followed by doripenem (80.3-82.6%). With the exception of amikacin, there were substantial inter-institutional differences in antimicrobial susceptibility. In comparison to the previous CLSI guidelines (M100-S21), the new CLSI guidelines (M100-S22) on the use of carbapenems and penicillins show that the MIC80 has been affected. The MDRP detection rates in 2011, 2012 and 2013 were 1.8% (8 strains), 1.8% (8 strains), and 2.8% (10 strains), respectively. The MBL detection rates were as follows: bla(VIM-2), 0.2% (1 strain) in 2011; bla(IMP-1), 0.9% (4 strains) in 2012, and 1.7% (6 strains, including bla(IMP-1) [3 strains], bla(IMP-2) [2 strains] and bla(VIM-2) [1 strain]) in 2013. PMID:27544978

  10. Antimicrobial susceptibility testing of Clostridium difficile using EUCAST epidemiological cut-off values and disk diffusion correlates.

    Science.gov (United States)

    Erikstrup, L T; Danielsen, T K L; Hall, V; Olsen, K E P; Kristensen, B; Kahlmeter, G; Fuursted, K; Justesen, U S

    2012-08-01

    With the emergence of reduced susceptibility of Clostridium difficile to metronidazole and vancomycin the value of antimicrobial susceptibility testing has increased. The aim of our study was to evaluate disk diffusion for susceptibility testing of C. difficile by comparing disk diffusion results with MICs from gradient tests and to propose zone diameter breakpoint correlates for the EUCAST epidemiological cut-off values (ECOFFs) recently published. We tested 211 clinical isolates of C. difficile, from patients with diarrhoea hospitalized at Aarhus and Odense University Hospitals, Denmark. Furthermore, ten clinical isolates of C. difficile from the Anaerobe Reference Laboratory, University Hospital of Wales, with known reduced susceptibility to either metronidazole or vancomycin, were included. Isolates were tested with Etest gradient strips and disk diffusion towards metronidazole, vancomycin and moxifloxacin on Brucella Blood Agar supplemented with hemin and vitamin K. We found an excellent agreement between inhibition zone diameter and MICs. For each MIC value, the inhibition zones varied from 0 to 8 mm, with 93% of values within 6 mm for metronidazole, 95% of values within 4 mm for vancomycin, and 98% of values within 4 mm for moxifloxacin. With proposed zone diameter breakpoints for metronidazole, vancomycin and moxifloxacin of WT ≥ 23 mm, WT ≥ 19 and WT ≥ 20 mm, respectively, we found no very major errors and only major errors below 2%. In conclusion, we suggest that disk diffusion is an option for antimicrobial susceptibility testing of C. difficile. PMID:22672504

  11. An Antimicrobial Susceptibility Management System

    OpenAIRE

    Farmer, James J.; O'Donnell, Edward D.

    1981-01-01

    A computerized system is described which is used to store, manipulate and retrieve antimicrobial susceptibility data in the clinical microbiology lab. Features include facilitated input of susceptibility data, rapid generation of reports, realtime access to data, and enhanced retrieval of information for Infection Control.

  12. Genetic antimicrobial susceptibility testing in Gram-negative sepsis - impact on time to results in a routine laboratory.

    Science.gov (United States)

    Kommedal, Øyvind; Aasen, Johanne Lind; Lindemann, Paul Christoffer

    2016-07-01

    Diagnostic testing of positive blood cultures is among the most critical tasks performed by clinical microbiology laboratories, and the total analysis time from sampling to results should be kept as short as possible. By providing identification of pelleted bacteria directly from positive blood-cultures, MALDI-TOF MS opens for relatively low-complex species-adjusted genetic susceptibility testing from the same bacterial pellet. In our lab routine, we prospectively evaluated a rapid in-house real-time PCR targeting the most common aminoglycoside and cephalosporin resistance genes in Escherichia coli and Klebsiella pneumoniae and measured time to preliminary susceptibility reporting for 138 samples. The results were compared to direct phenotypic susceptibility testing with interpretation after 6 h and overnight incubation respectively. Results from the genetic susceptibility testing were available for 69.5% (96/138) of the positive blood cultures within 24 h after sample collection. No phenotypic susceptibility results were available at this time. Compared to overnight direct susceptibility testing, the average time from sample collection to preliminary susceptibility reporting was reduced with 43%, from 45 h and 5 min to 25 h and 44 min, providing an earlier adjustment of antimicrobial therapy for 12 patients. Minor logistic adjustments have the potential to save yet another 4 h. PMID:27197792

  13. Comparison of efficacy and cost-effectiveness of BIOMIC VIDEO and Vitek antimicrobial susceptibility test systems for use in the clinical microbiology laboratory.

    OpenAIRE

    Berke, I; Tierno, P M

    1996-01-01

    Antimicrobial susceptibility testing expense may be a significant portion of a clinical microbiology laboratory's budget. This study compares the BIOMIC VIDEO system (Giles Scientific, Inc., New York, N.Y.) with the Vitek system (bioMérieux Vitek, Inc., Hazelwood, Mo.), an established automated method of antimicrobial susceptibility testing with the ability to generate MIC data. The BIOMIC system is relatively inexpensive and automates the reading of the classical disk agar diffusion test to ...

  14. Optimization and evaluation of Flexicult(®) Vet for detection, identification and antimicrobial susceptibility testing of bacterial uropathogens in small animal veterinary practice

    DEFF Research Database (Denmark)

    Guardabassi, Luca; Hedberg, Sandra; Jessen, Lisbeth Rem;

    2015-01-01

    testing of E. coli, Flexicult Vet B (commercial name Flexicult(®) Vet) is a time- and cost-effective point-of-care test to guide antimicrobial choice and facilitate implementation of antimicrobial use guidelines for treatment of UTIs in small animals, provided that clinical staff is adequately trained to......BACKGROUND: Urinary tract infection (UTI) is a common reason for antimicrobial prescription in dogs and cats. The objective of this study was to optimize and evaluate a culture-based point-of-care test for detection, identification and antimicrobial susceptibility testing of bacterial uro...... and susceptibility testing. Subsequently, the test was modified by inclusion of an oxacillin-containing compartment for detection of methicillin-resistant staphylococci. The performance of the modified product (Flexicult Vet B) for susceptibility testing was evaluated in vitro using a collection of...

  15. Antimicrobial activity of cefmetazole (CS-1170) and recommendations for susceptibility testing by disk diffusion, dilution, and anaerobic methods.

    Science.gov (United States)

    Jones, R N; Barry, A L; Fuchs, P C; Thornsberry, C

    1986-12-01

    Cefmetazole, formerly CS-1170, was found to have antimicrobial activity slightly superior to that of cefoxitin but a clinically usable antimicrobial spectrum that should be considered identical to that of cefoxitin. Disk diffusion and dilution test methods with cefmetazole correlated highly (r, greater than or equal to 0.95) with cefoxitin results. The recommended 30-micrograms cefmetazole disk interpretive breakpoints for susceptibility and resistance were greater than or equal to 18 mm (MIC, less than or equal to 8.0 micrograms/ml) and less than or equal to 14 mm (MIC, greater than or equal to 32 micrograms/ml), respectively. Cefmetazole and cefoxitin should be considered to be in the same antimicrobial spectrum class, requiring separate testing for other cephalosporins such as cephalothin, cefamandole, cefuroxime, and cefotetan. Recommended interpretive criteria performed well for fastidious organisms (Haemophilus influenzae, Neisseria meningitidis, and Branhamella catarrhalis) and for broth microdilution tests with anaerobes. Cefmetazole and cefoxitin broth disk elution tests for anaerobic bacteria produced higher rates of false susceptibility results. PMID:3097064

  16. Antimicrobial susceptibility testing of 230 Helicobacter pylori strains: importance of medium, inoculum, and incubation time

    DEFF Research Database (Denmark)

    Hartzen, S H; Andersen, L P; Bremmelgaard, A;

    1997-01-01

    No standardized method of susceptibility testing for Helicobacter pylori is currently available, so before a large agar dilution study comprising 230 H. pylori strains belonging to more than 80 genetically different groups was initiated, we performed a relatively small preliminary study to determ....... Consequently, susceptibility testing of all H. pylori strains is recommended in order to survey the development of resistance, and in our hands the described methodology was relatively easy to perform and the results were easy to read....

  17. Comparison of an Automated System with Conventional Identification and Antimicrobial Susceptibility Testing

    OpenAIRE

    Shalini Duggal; Rajni Gaind; Neha Tandon; Manorama Deb; Tulsi Das Chugh

    2012-01-01

    The present study was designed to compare a fully automated identification/antibiotic susceptibility testing (AST) system BD Phoenix (BD) for its efficacy in rapid and accurate identification and AST with conventional manual methods and to determine if the errors reported in AST, such as the (very major errors) VME (false susceptibility), (major errors) ME (false resistance), and (minor errors) MiE (intermediate category interpretation) were within the range certified by FDA. Identification a...

  18. Antimicrobial susceptibility of Campylobacter jejuni subsp. jejuni assessed by E-test and double dilution agar method in Southern Chile

    Directory of Open Access Journals (Sweden)

    Fernández H

    2000-01-01

    Full Text Available The susceptibility patterns of 108 Campylobacter jejuni subsp. jejuni clinical strains, to six antimicrobial agents was determined by using the E-test and the double dilution agar methods. Using both metods, no strain was found to be resistant to ciprofloxacin, erythromycin and gentamicin, but two (1.8% were resistant to tetracycline and all to aztreonam. Seven (6.5% strains were resistant to ampicillin by the E-test and five (4.6% by the double dilution agar method and by both meyhods. No great discrepancies were observed between both methods.

  19. Evaluation of a direct blood culture disk diffusion antimicrobial susceptibility test.

    Science.gov (United States)

    Doern, G V; Scott, D R; Rashad, A L; Kim, K S

    1981-11-01

    A total of 556 unique blood culture isolates of nonfastidious aerobic and facultatively anaerobic bacteria were examined by direct and standardized disk susceptibility test methods (4,234 antibiotic-organism comparisons). When discrepancies which could be accounted for by the variability inherent in disk diffusion susceptibility tests were excluded, the direct method demonstrated 96.8% overall agreement with the standardized method. A total of 1.6% minor, 1.5% major, and 0.1% very major discrepancies were noted. PMID:7325634

  20. Antimicrobial Susceptibility Testing of Mycobacterium bovis Isolates from Michigan White-Tailed Deer during the 2009 Hunting Season

    Directory of Open Access Journals (Sweden)

    Scott D. Fitzgerald

    2011-01-01

    Full Text Available Michigan has had an ongoing outbreak of endemic Mycobacterium bovis which has been recognized within and sustained by its free-ranging white-tailed deer population since 1994. Worldwide, organisms within the Mycobacterium tuberculosis complex have exhibited the ability to develop resistance to antimicrobial agents, resulting in both the multidrug-resistant (MDR and extensively drug-resistant (XDR strains of human tuberculosis. Michigan's Bovine Tuberculosis Working Group has conducted active antimicrobial susceptibility testing on wildlife isolates of the endemic M. bovis organism at five-year intervals to detect any emerging drug resistance patterns. The results of 33 white-tailed deer origin isolates collected from the 2009 hunting season are reported here. There continues to be no evidence of any drug resistance except for pyrazinamide resistance. These results are likely due to the lack of antibacterial treatment applied to either wildlife or domestic animals which would provide selection pressure for the development of drug resistance.

  1. Selection of media for antimicrobial susceptibility testing of fish pathogenic bacteria

    DEFF Research Database (Denmark)

    Dalsgaard, Inger

    normally used for cultivation of pathogens with specific growth requirements like Flavobacterium species and Renibacterium salmoninarum have been used for susceptibility testing. The Mueller-Hinton Agar and different modifications of this medium was used most frequently in published studies on resistant...

  2. Direct antimicrobial drug susceptibility testing of Mycobacterium tuberculosis by the radiometric method

    International Nuclear Information System (INIS)

    Direct-drug-susceptibility tests were performed on clinical specimens positive for acid-fast bacilli by either Ziehl-Neelsen or fluorochrome staining. The results of conventional agar dilution and a modified radiometric (BACTEC) method were compared. A total of 580 smear-positive specimens were tested by the BACTEC method at three separate sites. Three hundred and seventy-seven of these were culture positive for M. tuberculosis, and 343 (91%) yielded acceptable direct-susceptibility-test results. We used the conventional method to determine that 343 of 519 smear-positive specimens were culture positive for M. tuberculosis, and 212 (62%) produced acceptable results within 3 wks. Conventional results were reported in 3-4 wks, while the time required to obtain results with the BACTEC method ranged from 5 to 21 days (average 11.5 days). Results indicate that the radiometric method provides reportable results more frequently with time savings as compared to the conventional method

  3. Optimization and evaluation of Flexicult® Vet for detection, identification and antimicrobial susceptibility testing of bacterial uropathogens in small animal veterinary practice

    OpenAIRE

    Guardabassi, Luca; Hedberg, Sandra; Jessen, Lisbeth Rem; Damborg, Peter Panduro

    2015-01-01

    BACKGROUND: Urinary tract infection (UTI) is a common reason for antimicrobial prescription in dogs and cats. The objective of this study was to optimize and evaluate a culture-based point-of-care test for detection, identification and antimicrobial susceptibility testing of bacterial uro-pathogens in veterinary practice.METHODS: Seventy-two urine samples from dogs and cats with suspected UTI presenting to seven veterinary facilities were used by clinical staff and an investigator to estimate...

  4. Cell-on-hydrogel platform made of agar and alginate for rapid, low-cost, multidimensional test of antimicrobial susceptibility.

    Science.gov (United States)

    Sun, Han; Liu, Zhengzhi; Hu, Chong; Ren, Kangning

    2016-08-01

    Antimicrobial resistance (AMR) is a rapidly increasing threat to the effective treatment of infectious diseases worldwide. The two major remedies include: (1) using narrow-spectrum antibiotics based on rapid diagnosis; and (2) developing new antibiotics. A key part of both remedies is the antimicrobial susceptibility test (AST). However, the current standard ASTs that monitor colony formation are costly and time-consuming and the new strategies proposed are not yet practical to be implemented. Herein, we report a strategy to fabricate whole-hydrogel microfluidic chips using alginate-doped agar. This agar-based microfabrication makes it possible to prepare inexpensive hydrogel devices, and allows a seamless link between microfluidics and conventional agar-based cell culture. Different from common microfluidic systems, in our system the cells are cultured on top of the device, similar to normal agar plate culture; on the other hand, the microfluidic channels inside the hydrogel allow precise generation of linear gradient of drugs, thus giving a better performance than the conventional disk diffusion method. Cells in this system are not exposed to any shear flow, which allows the reliable tracking of individual cells and AST results to be obtained within 2-3 hours. Furthermore, our system could test the synergistic effect of drugs through two-dimensional gradient generation. Finally, the platform could be directly implemented to new drug discovery and other applications wherein a fast, cost-efficient method for studying the response of microorganisms upon drug administration is desirable. PMID:27452345

  5. Ten years of antimicrobial susceptibility testing of Salmonella from Danish pig farms

    DEFF Research Database (Denmark)

    Emborg, Hanne-Dorthe; Baggesen, Dorte Lau; Aarestrup, Frank Møller

    2008-01-01

    the following antimicrobials were determined: ampicillin, chloramphenicol, gentamicin, nalidixic acid, colistin, streptomycin, sulphonamide, tetracycline and trimethoprim. Results: No significant development of resistance occurred within the most important serovars, except Salmonella Typhimurium. A...

  6. In vitro antimicrobial activity and susceptibility testing of ofloxacin. Current status.

    Science.gov (United States)

    Fuchs, P C

    1989-12-29

    The fluoroquinolone, ofloxacin, exhibits a broad antibacterial spectrum. Based on our data and a review of the literature, ofloxacin inhibited essentially 100 percent of staphylococci, including oxacillin-resistant strains, Haemophilus influenzae, Neisseria spp. and Branhamella catarrhalis. Ninety-five percent of Enterobacteriaceae were susceptible to ofloxacin. Pseudomonas aeruginosa and enterococci were less susceptible: 79 and 63 percent, respectively, were susceptible (minimal inhibitory concentration [MIC], less than or equal to 2.0 micrograms/ml); 15 and 25 percent, respectively, were intermediate (MIC, 4 micrograms/ml); 3 and 6 percent, respectively, were resistant (MIC, more than or equal to 4 micrograms/ml). Clostridium spp., including Clostridium difficile, were resistant to ofloxacin, but other anaerobic species, including the Bacteroides fragilis group (over 90 percent) were either susceptible or intermediate to ofloxacin. Ofloxacin is bactericidal; minimal bactericidal concentrations of ofloxacin rarely exceed the MICs by one doubling concentration. A modest inoculum effect has been observed with ofloxacin: MICs with inocula of 10(7) colony-forming units/ml are often two- to fourfold higher than those with inocula of 5 x 10(5) colony-forming units/ml. Susceptible organisms exposed serially to increasing concentrations of nalidixic acid developed increasing resistance to not only nalidixic acid, but also to all other quinolones, including ofloxacin. Correlations of disk diffusion inhibitory zone diameters using the 5-micrograms ofloxacin disk with ofloxacin MICs have been performed, and the disk diffusion zone diameter breakpoints recommended are: susceptible, greater than or equal to 16 mm; intermediate, 13 to 15 mm; resistant, less than or equal to 12 mm. Quality control parameters also are summarized. PMID:2690614

  7. Rapid antimicrobial susceptibility testing of clinical isolates by digital time-lapse microscopy

    DEFF Research Database (Denmark)

    Fredborg, M; Rosenvinge, F S; Spillum, E; Kroghsbo, S; Wang, Mikala; Sondergaard, T E

    2015-01-01

    CelloScope system, to perform rapid AST. The oCelloScope system demonstrated a very high accuracy (96 % overall agreement) when determining the resistance profiles of four reference strains, nine clinical isolates, including multi-drug-resistant isolates, and three positive blood cultures. AST of clinical isolates...... short time-to-result, enabling same-day targeted antimicrobial therapy, facilitating antibiotic stewardship and better patient management. A full-scale validation of the oCelloScope system including more isolates is necessary to assess the impact of using it for AST....

  8. Polymyxins: Antimicrobial susceptibility concerns and therapeutic options

    Directory of Open Access Journals (Sweden)

    V Balaji

    2011-01-01

    Full Text Available The increasing prevalence of multidrug-resistant nosocomial pathogens such as Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae poses a great challenge to the treating physicians. The paucity of newer effective antimicrobials has led to renewed interest in the polymyxin group of drugs, as a last resort for treatment of gram-negative bacterial infections. There is a dearth of information on the pharmacological properties of colistin, leading to difficulties in selecting the right dose, dosing interval, and route of administration for treatment, especially in critically-ill patients. The increasing use of colistin over the last few years necessitates the need for accurate and reliable in vitro susceptibility testing methods. Development of heteroresistant strains as a result of colistin monotherapy is also a growing concern. There is a compelling need from the clinicians to provide options for probable and possible colistin combination therapy for multidrug-resistant bacterial infections in the ICU setting. Newer combination drug synergy determination tests are being developed and reported. There are no standardized recommendations from antimicrobial susceptibility testing reference agencies for the testing and interpretation of these drug combinations. Comparison and analysis of these reported methodologies may help to understand and assist the microbiologist to choose the best method that produces accurate results at the earliest. This will help clinicians to select the appropriate combination therapy. In this era of multidrug resistance it is important for the microbiology laboratory to be prepared, by default, to provide timely synergistic susceptibility results in addition to routine susceptibility, if warranted. Not as a favour or at request, but as a responsibility.

  9. Results of Use of WHO Global Salm-Surv External Quality Assurance System for Antimicrobial Susceptibility Testing of Salmonella Isolates from 2000 to 2007

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Seyfarth, Anne Mette; Jensen, Arne Bent;

    2009-01-01

    An international External Quality Assurance System (EQAS) for antimicrobial susceptibility testing of Salmonella was initiated in 2000 by the World Health Organization (WHO) Global Salm-Surv in order to enhance the capacities of national reference laboratories to obtain reliable data for surveill......An international External Quality Assurance System (EQAS) for antimicrobial susceptibility testing of Salmonella was initiated in 2000 by the World Health Organization (WHO) Global Salm-Surv in order to enhance the capacities of national reference laboratories to obtain reliable data for...... surveillance purposes worldwide. Seven EQAS iterations have been conducted from 2000 to 2007. In each iteration, participating laboratories submitted susceptibility results from 10 to 15 antimicrobial agents for eight Salmonella isolates and an Escherichia coli reference strain (ATCC 25922). A total of 287...... laboratories in 102 countries participated in at least one EQAS iteration. A large number of laboratories reported results for the E. coli ATCC 25922 reference strain which were outside the quality control ranges. Critical deviations for susceptibility testing of the Salmonella isolates varied from 4% in 2000...

  10. Analysis and Presentation of Cumulative Antimicrobial Susceptibility Test Data – The Influence of Different Parameters in a Routine Clinical Microbiology Laboratory

    OpenAIRE

    Kohlmann, Rebekka; Gatermann, Sören G

    2016-01-01

    Introduction Many clinical microbiology laboratories report on cumulative antimicrobial susceptibility testing (cAST) data on a regular basis. Criteria for generation of cAST reports, however, are often obscure and inconsistent. Whereas the CLSI has published a guideline for analysis and presentation of cAST data, national guidelines directed at clinical microbiology laboratories are not available in Europe. Thus, we sought to describe the influence of different parameters in the process of c...

  11. WHO global salm-surv external quality assurance system (EQAS): an important step toward improving the quality of Salmonella serotyping and antimicrobial susceptibility testing worldwide

    DEFF Research Database (Denmark)

    Petersen, A.; Aarestrup, Frank Møller; Angulo, F. J.; Wong, S.; Stohr, K.; Wegener, Henrik Caspar

    2002-01-01

    susceptibility testing through international training courses and an External Quality Assurance System (EQAS). In 2000, 44 WHO Global Salm-Surv member laboratories from 35 countries determined the serotype and antimicrobial susceptibility pattern for eight "blinded" Salmonella isolates. For serotyping, 73% of...... the results were correct. For susceptibility testing, 92% of the results were in agreement with the expected results. However, only 78% of the performed tests with the E. coli ATCC 25922 reference strain were within the quality control range specified by National Committee for Clinical Laboratory...... Standards (NCCLS) guidelines. These EQAS results demonstrate the need for further training to improve the performance of some of the laboratories. WHO Global Salm-Surv activities, including international training courses and EQAS, represent an important step toward improving the quality of Salmonella...

  12. Antimicrobial susceptibility pattern of Helicobacter suis strains.

    Science.gov (United States)

    Vermoote, Miet; Pasmans, Frank; Flahou, Bram; Van Deun, Kim; Ducatelle, Richard; Haesebrouck, Freddy

    2011-12-15

    Helicobacter suis is a very fastidious porcine gastric pathogen, which is also considered to be of zoonotic importance. In vitro antimicrobial susceptibility cannot be determined using standard assays, as this agent only grows in a biphasic medium with an acidic pH. Therefore, a combined agar and broth dilution method was used to analyse the activity of nine antimicrobial agents against nine H. suis isolates. After 48 h microaerobic incubation, minimal inhibitory concentrations (MICs) were determined by software-assisted calculation of bacterial growth. Only for enrofloxacin a bimodal distribution of MICs was demonstrated, indicating acquired resistance in one strain, which showed an AGT→AGG (Ser→Arg) substitution at codon 99 of gyrA. In conclusion, the assay developed here is suitable for determination of the antimicrobial susceptibility of H. suis isolates, although activity of acid sensitive antimicrobial agents may be higher than predicted from MIC endpoints. PMID:21733643

  13. Molecular Characterization and Antimicrobial Susceptibility Testing of Escherichia coli Isolates from Patients with Urinary Tract Infections in 20 Chinese Hospitals

    DEFF Research Database (Denmark)

    Cao, Xiaoli; Cavaco, Lina; Lv, Yuan;

    2011-01-01

    . An equally very high frequency of resistance and equally high levels of diversity in phylogroups, PFGE types, and plasmids were observed among community- and hospital-acquired E. coli isolates, indicating the presence of a large reservoir in the community and a long-term spread of cephalosporin resistance......A total of 222 urinary Escherichia coli isolates from 20 tertiary hospitals in 15 different provinces and 4 municipalities in mainland China were characterized by antimicrobial susceptibility, phylogrouping, and the presence of plasmid-mediated quinolone resistance genes. A subset of 138 suspected......%) being the most prevalent of these genes. Nine of the 13 CTX-M-15- or CTX-M-14-containing B2 isolates belonged to ST131. PFGE typing showed a high level of diversity, and plasmid analysis indicated a very large pool of different resistance plasmids mediating the spread of blaCTX-M genes in mainland China...

  14. Comparison of M.I.C.E. and Etest with CLSI agar dilution for antimicrobial susceptibility testing against oxacillin-resistant Staphylococcus spp.

    Directory of Open Access Journals (Sweden)

    Eloiza H Campana

    Full Text Available OBJECTIVE: The main objective of this study was to comparatively evaluate the performance of M.I.C.E. and Etest methodologies to that of agar dilution for determining the antimicrobial susceptibility profile of oxacillin-resistant Staphylococcus spp. METHODS: A total of 100 oxacillin-resistant Staphylococcus spp. isolates were collected from hospitalized patients at a teaching hospital. Antimicrobial susceptibility testing for vancomycin, teicoplanin and linezolid was performed using the reference CLSI agar dilution method (2009, Etest and M.I.C.E. methodologies. The MIC values were interpreted according to CLSI susceptibility breakpoints and compared by regression analysis. RESULTS: In general, the essential agreement (±1-log2 between M.I.C.E. and CLSI agar dilution was 93.0%, 84.0% and 77.0% for linezolid, teicoplanin and vancomycin, respectively. Essential agreement rates between M.I.C.E. and Etest were excellent (>90.0% for all antibiotics tested. Both strips (M.I.C.E. and Etest yielded two very major errors for linezolid. Unacceptable minor rates were observed for teicoplanin against CoNS and for vancomycin against S. aureus. CONCLUSIONS: According to our results, linezolid and teicoplanin MICs against all staphylococci and S. aureus, respectively, were more accurately predicted by M.I.C.E. strips. However, the Etest showed better performance than M.I.C.E. for predicting vancomycin MICs against all staphylococci. Thus, microbiologists must be aware of the different performance of commercially available gradient strips against staphylococci.

  15. [First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans/ Anaerobic Subcommittee of the Asociación Argentina de Microbiología].

    Science.gov (United States)

    Legaria, María C; Bianchini, Hebe M; Castello, Liliana; Carloni, Graciela; Di Martino, Ana; Fernández Canigia, Liliana; Litterio, Mirta; Rollet, Raquel; Rossetti, Adelaida; Predari, Silvia C

    2011-01-01

    Through time, anaerobic bacteria have shown good susceptibility to clinically useful antianaerobic agents. Nevertheless, the antimicrobial resistance profile of most of the anaerobic species related to severe infections in humans has been modified in the last years and different kinds of resistance to the most active agents have emerged, making their effectiveness less predictable. With the aim of finding an answer and for the purpose of facilitating the detection of anaerobic antimicrobial resistance, the Anaerobic Subcommittee of the Asociación Argentina de Microbiología developed the First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans. This document resulted from the compatibilization of the Clinical and Laboratory Standards Institute recommendations, the international literature and the work and experience of the Subcommittee. The Consensus document provides a brief taxonomy review, and exposes why and when anaerobic antimicrobial susceptibility tests should be conducted, and which antimicrobial agents can be used according to the species involved. The recommendations on how to perform, read and interpret in vitro anaerobic antimicrobial susceptibility tests with each method are exposed. Finally, the antibiotic susceptibility profile, the classification of antibiotics according to their in vitro activities, the natural and acquired mechanisms of resistance, the emerging resistance and the regional antibiotic resistance profile of clinically relevant anaerobic species are shown. PMID:21491069

  16. Agar Disk Diffusion and Automated Microbroth Dilution Produce Similar Antimicrobial Susceptibility Testing Results for Salmonella Serotypes Newport, Typhimurium, and 4,5,12:i-, But Differ in Economic Cost

    OpenAIRE

    Hoelzer, Karin; Cummings, Kevin J.; Warnick, Lorin D.; Ynte H. Schukken; Siler, Julie D.; Gröhn, Yrjo T.; Davis, Margaret A.; Besser, Tom E.; Wiedmann, Martin

    2011-01-01

    Data generated using different antimicrobial testing methods often have to be combined, but the equivalence of such results is difficult to assess. Here we compared two commonly used antimicrobial susceptibility testing methods, automated microbroth dilution and agar disk diffusion, for 8 common drugs, using 222 Salmonella isolates of serotypes Newport, Typhimurium, and 4,5,12:i-, which had been isolated from clinical salmonellosis cases among cattle and humans. Isolate classification corresp...

  17. Analysis and Presentation of Cumulative Antimicrobial Susceptibility Test Data--The Influence of Different Parameters in a Routine Clinical Microbiology Laboratory.

    Directory of Open Access Journals (Sweden)

    Rebekka Kohlmann

    Full Text Available Many clinical microbiology laboratories report on cumulative antimicrobial susceptibility testing (cAST data on a regular basis. Criteria for generation of cAST reports, however, are often obscure and inconsistent. Whereas the CLSI has published a guideline for analysis and presentation of cAST data, national guidelines directed at clinical microbiology laboratories are not available in Europe. Thus, we sought to describe the influence of different parameters in the process of cAST data analysis in the setting of a German routine clinical microbiology laboratory during 2 consecutive years.We developed various program scripts to assess the consequences ensuing from different algorithms for calculation of cumulative antibiograms from the data collected in our clinical microbiology laboratory in 2013 and 2014.One of the most pronounced effects was caused by exclusion of screening cultures for multi-drug resistant organisms which decreased the MRSA rate in some cases to one third. Dependent on the handling of duplicate isolates, i.e. isolates of the same species recovered from successive cultures on the same patient during the time period analyzed, we recorded differences in resistance rates of up to 5 percentage points for S. aureus, E. coli and K. pneumoniae and up to 10 percentage points for P. aeruginosa. Stratification by site of care and specimen type, testing of antimicrobials selectively on resistant isolates, change of interpretation rules and analysis at genus level instead of species level resulted in further changes of calculated antimicrobial resistance rates.The choice of parameters for cAST data analysis may have a substantial influence on calculated antimicrobial resistance rates. Consequently, comparability of cAST reports from different clinical microbiology laboratories may be limited. We suggest that laboratories communicate the strategy used for cAST data analysis as long as national guidelines for standardized cAST data

  18. Antimicrobial susceptibility pattern of urinary tract pathogens

    International Nuclear Information System (INIS)

    Microbial drug resistance is a major problem in the treatment of infectious diseases worldwide. The purpose of this survey is to determine the prevalence of the type of bacterial agents that cause urinary infection and to assess the antimicrobial sensitivity pattern in the Urmia Medical University, Iran. In the period between 2005 and 2006, urine cultures collected were analyzed. Positive culture was defined as growth of a single bacterial species with colony count of > 100,000 CFU/mL. Stratification was done according to age-group and gender. Statistical tests used included chi-square to evaluate differences between susceptibility rates. A total of 803 urine culture positive patients were studied of whom 81.6% were females and 18.4% were males. The common micro-organisms isolated were E. coli (78.58%), Klebsiella (5.48%), Proteus and Staphylococcus. About 89% of the E. coli isolated showed sensitivity to cephtizoxin, 83.9% to gentamycin and 83.2% to ciprofloxacin; the highest resistance was shown to ampicillin and cotrimoxazole. Surveys of this nature will give a clear idea about the bacteriologic profile in a given institution as well their antibiotic sensitivity profile. This will act as a guide to commencing empirical antibiotic treatment in patients with urinary infections until such time culture reports are available. (author)

  19. Susceptibility of bifidobacteria of animal origin to selected antimicrobial agents.

    Science.gov (United States)

    Mayrhofer, Sigrid; Mair, Christiane; Kneifel, Wolfgang; Domig, Konrad J

    2011-01-01

    Strains of the genus Bifidobacterium are frequently used as probiotics, for which the absence of acquired antimicrobial resistance has become an important safety criterion. This clarifies the need for antibiotic susceptibility data for bifidobacteria. Based on a recently published standard for antimicrobial susceptibility testing of bifidobacteria with broth microdilution method, the range of susceptibility to selected antibiotics in 117 animal bifidobacterial strains was examined. Narrow unimodal MIC distributions either situated at the low-end (chloramphenicol, linezolid, and quinupristin/dalfopristin) or high-end (kanamycin, neomycin) concentration range could be detected. In contrast, the MIC distribution of trimethoprim was multimodal. Data derived from this study can be used as a basis for reviewing or verifying present microbiological breakpoints suggested by regulatory agencies to assess the safety of these micro-organisms intended for the use in probiotics. PMID:22312561

  20. WHO global salm-surv external quality assurance system (EQAS): an important step toward improving the quality of Salmonella serotyping and antimicrobial susceptibility testing worldwide

    DEFF Research Database (Denmark)

    Petersen, A.; Aarestrup, Frank Møller; Angulo, F. J.;

    2002-01-01

    Initiated in 2000, WHO Global Salm-Surv is a global network of epidemiologists and microbiologists involved in Salmonella surveillance. WHO Global Salm-Surv seeks to enhance the capacity of national and regional reference laboratories to conduct Salmonella serotyping and antimicrobial susceptibil......Initiated in 2000, WHO Global Salm-Surv is a global network of epidemiologists and microbiologists involved in Salmonella surveillance. WHO Global Salm-Surv seeks to enhance the capacity of national and regional reference laboratories to conduct Salmonella serotyping and antimicrobial......% of the results were correct. For susceptibility testing, 92% of the results were in agreement with the expected results. However, only 78% of the performed tests with the E. coli ATCC 25922 reference strain were within the quality control range specified by National Committee for Clinical Laboratory Standards...... (NCCLS) guidelines. These EQAS results demonstrate the need for further training to improve the performance of some of the laboratories. WHO Global Salm-Surv activities, including international training courses and EQAS, represent an important step toward improving the quality of Salmonella serotyping...

  1. Antimicrobial susceptibility testing trends and accuracy in the United States. A review of the College of American Pathologists Microbiology Surveys, 1972-1989. Microbiology Resource Committee of the College of American Pathologists.

    Science.gov (United States)

    Jones, R N; Edson, D C

    1991-05-01

    The ability of the College of American Pathologists Microbiology Surveys subscriber laboratories to perform antimicrobial susceptibility testing accurately has improved slightly since 1984. Currently (1989 surveys), the accuracies for disk diffusion and minimum inhibitory concentration antimicrobial susceptibility testing were 98.2% and 96.1%, respectively. Disk diffusion testing has recently (since 1986) become more popular, along with rapid automated systems, such as the AMS-Vitek System (St Louis, Mo). Rapid tests for beta-lactamase and chloramphenicol acetyltransferase have performed well. Quality control procedures have switched to a cost-effective weekly frequency pattern for nearly 70% of laboratories. Some antimicrobial susceptibility testing problems still exist among anaerobic bacterial methods, procedures for fastidious organisms (Haemophilus, Streptococcus species, Moraxella, pneumococci, gonococci), tests for oxacillin-resistant staphylococci, and the methods for use against nonenteric gram-negative or gram-positive bacilli. Antimicrobial susceptibility testing users subscribing to the College of American Pathologists surveys should strictly follow the National Committee for Clinical Laboratory Standards interpretive and quality control criteria to assure the best performance with the Clinical Laboratory Improvement Act, 1988, compliant College of American Pathologists proficiency sample program. PMID:2021310

  2. Quality control ranges for testing broth microdilution susceptibility of Flavobacterium columnare and F. psychrophilum to nine antimicrobials

    DEFF Research Database (Denmark)

    Gieseker, Charles M.; Mayer, Tamara D.; Crosby, Tina C.;

    2012-01-01

    salmonicida subsp. salmonicida ATCC 33658 against 10 antimicrobials (ampicillin, enrofloxacin, erythromycin, florfenicol, flumequine, gentamicin, ormetoprim/sulfadimethoxine, oxolinic acid, oxytetracycline, and trimethoprim/sulfamethoxazole) in diluted (4 g l−1) cation-adjusted Mueller-Hinton broth incubated...

  3. Antimicrobial susceptibility testing of Escherichia coli strains isolated from urinary tract infections to fluoroquinolones and detection of gyrA mutations in resistant strains

    Directory of Open Access Journals (Sweden)

    Akbari-Nakhjavani F.

    2007-05-01

    Full Text Available Widespread uses of fluoroquinolones have resulted in increasing incidences of resistance against these agents all over the world. The aim of this study was to assess, susceptibility of Escherichia coli strains from patients with Urinary Tract Infection against common fluoroquinolones and detection of mutations in the gyrA gene. Antimicrobial susceptibility testing of 164 E.coli isolates from patients with UTI, was evaluated by disk agar diffusion (DAD and MIC methods. Polymerase chain reaction of E.coli strains were performed by amplification of Quinolone Resistance Determining Region (QRDR of gyrA gene. PCR products were tested by Conformational Sensitive Gel Electrophoresis (CSGE and those with hetrodublexes were selected and examined by DNA sequencing. According to disc agar diffusion, 49.3% were resistant to nalidixic acid, 41.4% to norfloxacin, 44.5% to ofloxacin and 40.2 % to ciprofloxacin. By Minimal Inhibitory Concentration (MIC testing a high-level of resistance (42.1% to ciprofloxacin was observed. Mutations in codons 83 and 87 in all 81 isolates were positive by CSGE method.

  4. Susceptibility and resistance of ruminal bacteria to antimicrobial feed additives.

    OpenAIRE

    Nagaraja, T. G.; Taylor, M.B.

    1987-01-01

    Susceptibility and resistance of ruminal bacterial species to avoparcin, narasin, salinomycin, thiopeptin, tylosin, virginiamycin, and two new ionophore antibiotics, RO22-6924/004 and RO21-6447/009, were determined. Generally, antimicrobial compounds were inhibitory to gram-positive bacteria and those bacteria that have gram-positive-like cell wall structure. MICs ranged from 0.09 to 24.0 micrograms/ml. Gram-negative bacteria were resistant at the highest concentration tested (48.0 micrograms...

  5. In vitro susceptibilities of Mycobacterium tuberculosis to 10 antimicrobial agents.

    OpenAIRE

    Byrne, S K; Crawford, C E; Geddes, G L; Black, W A

    1988-01-01

    After preliminary in vitro screening of 10 antimicrobial agents against Mycobacterium tuberculosis, the MICs of the 6 most promising agents against 27 clinical isolates were determined by agar dilution. The two quinolone compounds tested (difloxacin and A-56620) were the most active, each inhibiting 50% of the strains at concentrations of 4 micrograms/ml. M. tuberculosis strains previously shown to be resistant to isoniazid, streptomycin, rifampin, or ethambutol were as susceptible to these q...

  6. Performance of the EUCAST disk diffusion method, the CLSI agar screen method, and the Vitek 2 automated antimicrobial susceptibility testing system for detection of clinical isolates of Enterococci with low- and medium-level VanB-type vancomycin resistance

    DEFF Research Database (Denmark)

    Hegstad, Kristin; Giske, Christian G; Haldorsen, Bjørg; Matuschek, Erika; Schønning, Kristian; Leegaard, Truls M; Kahlmeter, Gunnar; Sundsfjord, Arnfinn

    2014-01-01

    Different antimicrobial susceptibility testing methods to detect low-level vancomycin resistance in enterococci were evaluated in a Scandinavian multicenter study (n=28). A phenotypically and genotypically well-characterized diverse collection of Enterococcus faecalis (n=12) and Enterococcus...... careful monitoring of the vancomycin concentration in the plates. Moreover, disk diffusion methodology requires that personnel be trained in interpreting zone edges....

  7. In vitro susceptibility testing of anaerobic bacteria.

    Science.gov (United States)

    Washington, J A

    1979-01-01

    In vitro susceptibility testing of anaerobic bacteria should be limited to isolates from persistent or recurrent infections that have been treated adequately and appropriately with antimicrobial agents and, in reference centers, to collections of isolates in order to monitor alterations in susceptibility of species to various antimicrobial agents. An agar dilution reference method is being evaluated currently; however, practicality limits sporadic testing of single isolates to disk elution or broth dilution techniques. No single disk diffusion method has yet been found to be acceptable for testing anaerobic bacteria, and the results obtained with standardized procedures for aerobic and facultatively anaerobic bacteria are not applicable to anaerobic bacteria. PMID:288163

  8. Differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis

    Science.gov (United States)

    Maboni, Grazieli; Gressler, Leticia T.; Espindola, Julia P.; Schwab, Marcelo; Tasca, Caiane; Potter, Luciana; de Vargas, Agueda Castagna

    2015-01-01

    The aim of this study was to determine the differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis. Thirty-two strains of Moraxella spp. isolated from cattle and sheep with infectious keratoconjunctivitis were tested via broth microdilution method to determine their susceptibility to ampicillin, cefoperazone, ceftiofur, cloxacillin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline and penicillin. The results demonstrated that Moraxella spp. strains could be considered sensitive for most of the antimicrobials tested in this study, but differences between the antimicrobial susceptibility profiles of these three Moraxella species were found. M. bovis might differ from other species due to the higher MIC and MBC values it presented. PMID:26273272

  9. Susceptibility of Aeromonas Hydophila Isolates to Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Igor Stojanov

    2010-05-01

    Full Text Available Aeromonas hydrophila is a microorganism widely distributed in nature: in water, soil, food. It is also part of the normal bacterial flora of many animals. As an opportune microorganism it is a secondary biological agent that contributes to the occurrence of a fish disease and its deterioration. Frequently, its presence is an indication of bad zoohygiene and zootechnical conditions in fish ponds. Reduced quality and quantity of feed, mechanical injuries, parasitosis, seasonal oscillation in temperature present some of the factors that produce favorable conditions for bacterial proliferation of aeromonas in fish ponds, so clinical symptoms of the disease occur. Aeromonas is almost always present in clinical isolates and may be unjustly accused for bad health of fish. Antibiotic therapy is applied even when the clinical findings are clear, what certainly effects the susceptibility to chemotherapeutics. The subject of our work was bacteriological examination of the material obtained from the carps with the observed skin changes and the carps without these changes. Also, antimicrobial susceptibility of Aeromonas hydrophila was tested. The aim of this research was to determined the presence of Aeromonas hydrophilia in the carp ponds and to test antibiotic susceptibility. The material consisted of the samples from the fish ponds where the carps were with and without changed skin. The method the isolation of Aeromonas hydrophila was used. The diffusion disk technique was used for testing antibiotic susceptibility. The isolates were tested for their susceptibility to Florephenikol, Flumequine, Olaqindox and Oxitetracycline. The obtained results point that antimicrobial susceptibility was the same regardless of the origin of the samples, i.e. the resistance was the same for both groups of samples (the strains isolated from the fish with skin changes and the strains from fish without changes on skin. The strains were highly resistant: 35% were resistant to

  10. Antimicrobial susceptibility profile of Neisseria gonorrhoeae at STI clinic

    Directory of Open Access Journals (Sweden)

    Shilpee C

    2008-01-01

    Full Text Available A total of 100 consecutive patients who attended a sexually transmitted infections clinic were studied. Thirteen had gonococcal urethritis, of which 10 showed growth of Neisseria gonorrhoeae on culture. All the isolates were tested for antimicrobial susceptibility by Australian Gonococcal Surveillance Programme (AGSP method and beta lactamase production by chromogenic cephalosporin test. Four patients were co-infected with each of the following: HIV, HBV and Chlamydia trachomatis . Gonococcal urethritis (13% was found more in male patients. Ten percent gonococcal isolates were penicillinase-producing N. gonorrhoeae , and another 10% were tetracycline-resistant N. gonorrhoeae .

  11. Clinical laboratory evaluation of the Abbott MS-2 automated antimicrobial susceptibility testing system: report of a collaborative study.

    OpenAIRE

    Thornsberry, C; Anhalt, J P; Washington, J A; McCarthy, L R; Schoenknecht, F D; Sherris, J. C.; Spencer, H J

    1980-01-01

    The MS-2 system (Abbott Diagnostics, Division of Abbott Laboratories, Dallas, Tex.) was evaluated for its efficacy in determining the susceptibilities of both clinical and selected challenge (nonfastidious, facultative, and aerobic) isolates. The MS-2 results were compared with standard Kirby-Bauer disk diffusion and microdilution results by using fresh clinical isolates. For gram-positive isolates other than enterococci, overall agreement between MS-2 and reference results was 93 to 98%. Wit...

  12. Investigation of clostridium difficile interspecies relatedness using multilocus sequence typing, multilocus variable-number tandem-repeat analysis and antimicrobial susceptibility testing

    OpenAIRE

    Rodriguez Diaz, Cristina; Avesani, Véronique; Taminiau, Bernard; Van Broeck, Johan; Brévers, Bastien; Delmée, Michel; Daube, Georges

    2015-01-01

    Multilocus sequence typing (MLST), multilocus variable-number tandem-repeat analysis (MLVA) and antimicrobial susceptibility were performed on 37 animal and human C. difficile isolates belonging to 15 different PCR-ribotypes in order to investigate the relatedness of human and animal isolates and to identify possible transmission routes. MLVA identified a total of 21 different types while MLST only distinguished 12 types. Identical C. difficile strains were detected in the same animal spe...

  13. Antimicrobial Susceptibility and Clinical Sources of Dolosigranulum pigrum Cultures

    OpenAIRE

    LaClaire, L.; Facklam, R

    2000-01-01

    Antimicrobial susceptibilities of 27 clinical isolates of Dolosigranulum pigrum were determined. All were susceptible to amoxicillin, cefotaxime, cefuroxime, clindamycin, levofloxacin, meropenem, penicillin, quinupristin-dalfopristin, rifampin, tetracycline, and vancomycin. Fifteen of the isolates were intermediate to chloramphenicol. One isolate was resistant to trimethoprim-sulfamethoxazole. Two isolates were susceptible, 10 were intermediate, and 15 were resistant to erythromycin.

  14. Antimicrobial Susceptibility of Gram-Negative Uropathogens Isolated From Obstetric Patients

    OpenAIRE

    Patrick Duff; Rodney K. Edwards; Jamie, Whitney E.

    2002-01-01

    OBJECTIVE: To evaluate the antimicrobial susceptibility of Gram-negative uropathogens isolated from pregnant women. METHODS: We performed a snapshot cohort study of women receiving care in the University of Florida prenatal clinics during March 2000. Subjects with asymptomatic bacteriuria or cystitis were identified and the antimicrobial susceptibility of each pathogen was recorded. Data were analyzed using chi-square, Fisher's exact test and ninety-five percent confidence intervals, as appro...

  15. Antimicrobial susceptibility of standard strains of nontuberculous mycobacteria by microplate Alamar Blue assay.

    Directory of Open Access Journals (Sweden)

    Guilian Li

    Full Text Available In this study, 24 standard nontuberculous mycobacteria (NTM species strains including 12 slowly growing mycobacteria strains and 12 rapidly growing mycobacteria strains were subjected to drug susceptibility testing using microplate Alamar Blue assay-based 7H9 broth. The most active antimicrobial agents against the 24 NTM strains were streptomycin, amikacin, the fluoroquinolones, and the tetracyclines. Mycobacterium chelonae, Mycobacterium abscessus, Mycobacterium bolletii, and Mycobacterium simiae are resistant to most antimicrobial agents. The susceptibility results of this study from 24 NTM standard strains can be referenced by clinicians before susceptibility testing for clinical isolates is performed or when conditions do not allow for susceptibility testing. The application of broth-based methods is recommended by the Clinical and Laboratory Standards Institute, and the documentation of the susceptibility patterns of standard strains of mycobacteria can improve the international standardization of susceptibility testing methods.

  16. A simple and sensitive quality control method of the anaerobic atmosphere for identification and antimicrobial susceptibility testing of anaerobic bacteria

    DEFF Research Database (Denmark)

    Justesen, Tage; Justesen, Ulrik Stenz

    2013-01-01

    The maintenance of a strict anaerobic atmosphere is essential for the culture of strict anaerobic bacteria. We describe a simple and sensitive quality control method of the anaerobic atmosphere, based on the measurement of the zone diameter around a 5-μg metronidazole disk when testing an...

  17. Preliminary antimicrobial susceptibility: possibility of early and effective therapy during treatment of septic patients

    Directory of Open Access Journals (Sweden)

    Maria Antonietta Distasi

    2014-03-01

    Full Text Available Blood cultures have the drawback of requiring long time to be carried out. Our study was designed with the aim of early reports on both causing agents and preliminary antimicrobial susceptibility. We carried out a direct antimicrobial susceptibility on 79 positive blood cultures (42 for Gram-negative bacteria of which 21 MDRO; 22 for staphylococci of which 15 S. aureus; and 15 Enterococci/Streptococci employing E-test strips deposited on Müller-Hinton Agar for staphylococci and Gram-negative bacteria, and Müller-Hinton Agar + 5% of blood for enterococci/streptococci. MICs were compared to the antimicrobial susceptibility tests carried out using Vitek2. On the basis of the interpretative criteria (SIR, the comparison between the direct antimicrobial susceptibility and the routine antimicrobial susceptibility, showed a concordance from 92.6% up to 100% for Gram-negative bacteria; from 90.0% up to 100% for staphylococci; from 86.7% up to 100% for streptococci/enterococci, respectively. With regard to MICs comparison, good concordance was detected on the basis of ± 1 doubling dilution. Moreover, this work allowed, in the case of Gram-negative bacteria, either the early identification of multidrug-resistant organisms or providing the MIC evaluation in a broader interval than it would be possible by the reference antimicrobial susceptibility.

  18. Effect of Carbon Dioxide on Testing of Susceptibilities of Respiratory Tract Pathogens to Macrolide and Azalide Antimicrobial Agents

    OpenAIRE

    Johnson, M M; Hill, S. L.; Piddock, Laura J. V.

    1999-01-01

    The in vitro activities of erythromycin, azithromycin, and clarithromycin against 178 clinical isolates from the lower respiratory tract of patients with chronic obstructive pulmonary disease were determined by an agar dilution method. The plates were incubated in air alone or in 5% carbon dioxide. The MICs measured in air alone were lower for most isolates than those measured in 5% carbon dioxide, illustrating the “pH effect” of incubation in carbon dioxide. Testing of isolates in 5% carbon ...

  19. Optimization and evaluation of Flexicult(®) Vet for detection, identification and antimicrobial susceptibility testing of bacterial uropathogens in small animal veterinary practice

    DEFF Research Database (Denmark)

    Guardabassi, Luca; Hedberg, Sandra; Jessen, Lisbeth Rem; Damborg, Peter Panduro

    2015-01-01

    and susceptibility testing. Subsequently, the test was modified by inclusion of an oxacillin-containing compartment for detection of methicillin-resistant staphylococci. The performance of the modified product (Flexicult Vet B) for susceptibility testing was evaluated in vitro using a collection of...... Staphylococcus pseudintermedius for Flexicult Vet B. The latter error can be prevented by categorizing staphylococcal strains growing in the oxacillin compartment as resistant to all β-lactams. CONCLUSIONS: Despite the shortcomings regarding species identification by clinical staff and β-lactam susceptibility...

  20. Susceptibility of archaea to antimicrobial agents: applications to clinical microbiology.

    Science.gov (United States)

    Khelaifia, S; Drancourt, M

    2012-09-01

    We herein review the state of knowledge regarding the in vitro and in vivo susceptibility of archaea to antimicrobial agents, including some new molecules. Indeed, some archaea colonizing the human microbiota have been implicated in diseases such as periodontopathy. Archaea are characterized by their broad-spectrum resistance to antimicrobial agents. In particular, their cell wall lacks peptidoglycan, making them resistant to antimicrobial agents interfering with peptidoglycan biosynthesis. Archaea are, however, susceptible to the protein synthesis inhibitor fusidic acid and imidazole derivatives. Also, squalamine, an antimicrobial agent acting on the cell wall, proved effective against human methanogenic archaea. In vitro susceptibility data could be used to design protocols for the decontamination of complex microbiota and the selective isolation of archaea in anaerobic culture. PMID:22748132

  1. Antimicrobial susceptibility test in Brachyspira pilosicoli strains isolated from commercial layers farms in Colombia PRUEBAS DE SENSIBILIDAD FRENTE A AGENTES ANTIMICROBIANOS EN CEPAS DE Brachyspira pilosicoli AISLADAS A PARTIR DE PONEDORAS COMERCIALES EN COLOMBIA

    OpenAIRE

    Figueroa Ramìrez Judith; Pulido Landinez Martha; Alvarez Mira Diana Marcela

    2009-01-01

    Intestinal Spirochaetes of the genus Brachyspira cause important diseases in swine and poultry. An increasing problem in the presentation of resistant strains to the antimicrobial drugs usually used to treat the intestinal spirochaetosis in swine has been evidenced and this could be applicable to the isolations from poultry. There are very few reports of in vitro antimicrobial susceptibility of Brachyspira spp. isolated from birds. In this study the antimicrobial susceptibility of twelve Brac...

  2. In vitro susceptibility of Campylobacter jejuni from Kuwait to tigecycline & other antimicrobial agents

    Directory of Open Access Journals (Sweden)

    M John Albert

    2013-01-01

    Full Text Available Background & objectives: There is an increasing frequency of resistance of Campylobacter jejuni to antimicrobial agents making treatment difficult. In this study, the in vitro susceptibility of C. jejuni isolates collected over an eight year period was tested against tigecycline, a glycylcycline, the previously tested antimicrobial agents in Kuwait, ciprofloxacin, erythromycin and tetracycline, and other antimicrobial agents not previously tested in Kuwait, amoxicillin-clavulanic acid, gentamicin, imipenem and meropenem. Methods: A total of 97 C. jejuni isolates from diarrhoeal stools of Kuwaiti patients during 2002-2010 were studied for susceptibility to the above antimicrobial agents by E test. Results: Erythromycin resistance increased from 5.0 per cent in 2002-2003 to 13.8 per cent in 2007-2010. The figures for ciprofloxacin resistance for the same periods were 53 and 65.5 per cent, respectively. Tetracycline resistance increased from 40.0 per cent in 2003-2006 to 62.1 per cent in 2007-2010 (P=0.05. However, all isolates were uniformly susceptible to tigecycline and other antimicrobial agents. Interpretation & conclusions: There was a progressive increase in the prevalence of resistance to ciprofloxacin, erythromycin and tetracycline. As all isolates were uniformly susceptible to tigecycline, this antimicrobial agent can be considered as a potential candidate for treatment in clinical studies.

  3. Prediction of piperacillin-tazobactam susceptibility among Enterobacteriaceae, Pseudomonas aeruginosa, and other bacteria using ticarcillin-clavulanic acid, ceftazidime, and other broad-spectrum antimicrobial in vitro test results.

    Science.gov (United States)

    Jones, R N; Sutton, L D; Cantrell, H F; Lankford, R B

    1994-11-01

    The ability of various in vitro beta-lactam susceptibility test results to predict the susceptibility of piperacillin-tazobactam (a new beta-lactam-beta-lactamase inhibitor combination) was assessed using more than 46,000 recent clinical isolates. The organisms were tested by reference-quality National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution procedures and interpreted by the currently published NCCLS criteria. The recommended antimicrobial tests that would accurately predict the piperacillin-tazobactam in vitro efficacy had an overall very major, false-susceptible rate of only 0.6% (sulbactam (1.8%) results; for Haemophilus influenzae and Moraxella catarrhalis use cefotaxime or cefuroxime or ceftriaxone (1.5%); and for staphylococci use oxacillin by NCCLS recommendations. When the piperacillin-tazobactam testing reagents become available, the direct testing of this combination should be applied to relevant clinical isolates. The piperacillin-tazobactam break points should be reassessed as indicated by the cited minimum inhibitory concentration population analysis to improve predictive accuracy; H. influenzae susceptibility modified to < or = 2/4 micrograms/ml and Enterococcus species susceptibility tested at < or = 16/4 micrograms. PMID:7874881

  4. Susceptibility of Stenotrophomonas maltophilia clinical strains in China to antimicrobial combinations.

    Science.gov (United States)

    Hu, Li-Fen; Gao, Li-Ping; Ye, Ying; Chen, Xi; Zhou, Xiang-Tian; Yang, Hai-Fei; Liiu, Yan-Yan; Mei, Qing; Li, Jia-Bin

    2014-10-01

    We aimed to investigate the activity levels of several combinations of antimicrobials against Stenotrophomonas maltophilia. In this study, the antimicrobial susceptibility of S. maltophilia clinical isolates was determined, and the synergistic activity of three pairs of antimicrobial combinations was evaluated by the fractional inhibitory concentration index (FICI). The antimicrobial susceptibility in vitro against 83 S. maltophilia strains was greater for minocycline (80·7%) than for trimethoprim-sulfamethoxazole (51·8%), and levofloxacin (50·6%). The rate of resistance was highest for ticarcillin-clavulanate and ceftazidime (63·8%) and resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was 48·2%. All three combinations were tested against susceptible isolates. Two of the combinations, TMP-SMX+ceftazidime and levofloxacin+ceftazidime were more effective than the combination of TMP-SMX+levofloxacin. We recommend acquiring more clinical data in order to explore combination therapy, which is a promising treatment of S. maltophilia infections. PMID:24588423

  5. Prevalence and antimicrobial susceptibility of respiratory pathogens in patients with cystic fibrosis

    OpenAIRE

    Vilma Almeida Paixão; Tânia Fraga Barros; Clélia Maria C Mota; Tamy Fagundes Moreira; Maria Angélica Santana; Joice Neves Reis

    2010-01-01

    Respiratory infection is very common in patients suffering from cystic fibrosis (CF). However, the antimicrobial resistance rate of isolates from CF patients is not often documented. In this study, 279 respiratory specimens of 146 patients were prospectively collected from July to December 2006. Microbiological cultures and antimicrobial susceptibility tests of the most frequently isolated bacteria were performed. Sputum and oropharyngeal swabs were processed for culture. During the study per...

  6. Differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis

    Directory of Open Access Journals (Sweden)

    Grazieli Maboni

    2015-06-01

    Full Text Available The aim of this study was to determine the differences in the antimicrobial susceptibility profiles of Moraxella bovis, M. bovoculi and M. ovis. Thirty-two strains of Moraxella spp. isolated from cattle and sheep with infectious keratoconjunctivitis were tested via broth microdilution method to determine their susceptibility to ampicillin, cefoperazone, ceftiofur, cloxacillin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline and penicillin. The results demonstrated that Moraxella spp. strains could be considered sensitive for most of the antimicrobials tested in this study, but differences between the antimicrobial susceptibility profiles of these three Moraxella species were found. M. bovis might differ from other species due to the higher MIC and MBC values it presented.

  7. Antimicrobial Susceptibility of Staphylococci Isolated from Clinical Mastitis in Dairy Cows in Two Regions of Kosovo

    OpenAIRE

    DRITON SYLEJMANI; AVNI ROBAJ; AFRIM HAMIDI

    2015-01-01

    This study was undertaken to evaluate antibiotic susceptibility of 26 strains of Coagulase Negative Staphylococci (CNS) and 18 strains of Staphylococcus aureus isolated from samples of dairy cows with clinical mastitis. The isolates species of staphylococci were identified by using coagulase test (using rabbit plasma) and API Staph system (bioMėrieux SA) which differentiates S. aurues from other staphylococci. Isolates were tested for antimicrobial susceptibility on Mueller Hinton...

  8. Campylobacter MLST Subtypes and Antimicrobial Susceptibility of Broiler Cecal Isolates: A Two Year Study from 142 Commercial Flocks

    Science.gov (United States)

    Introduction: Campylobacter spp. are recognized as important agents of human foodborne gastroenteritis. To monitor trends in food safety and public health, antimicrobial susceptibility testing of Campylobacter derived from poultry products and infected patients has become common practice in both r...

  9. Antimicrobial susceptibility of clinical isolates of Haemophilus influenzae to ampicillin-sulbactam.

    Science.gov (United States)

    Mortensen, J E; LaRocco, M; Himes, S L; Inderlied, C; Daly, J A; Campos, J M; Mendelman, P M

    1990-01-01

    A total of 1092 clinical isolates of Haemophilus influenzae (306 type b; 786 non-type-b), from five medical centers were obtained during 1987 and 1988. Disk diffusion antimicrobial susceptibilities were obtained for all isolates, and broth microdilution susceptibilities were obtained for 502 isolates. Beta-lactamase was produced by 34.3% of type-b and 22.1% of non-type-b isolates, with some geographic variations. Using disk diffusion antimicrobial susceptibility testing, all isolates were susceptible to ampicillin-sulbactam, ceftriaxone, cefuroxime, and rifampin; two isolates were resistant to chloramphenicol. Whether tested using a fixed ratio of ampicillin to sulbactam of 2:1 or a fixed concentration of sulbactam, the ampicillin-sulbactam combination demonstrated good activity against clinical isolates of H. influenzae. Only 8 of the 1092 isolates did not produce beta-lactamase but demonstrated MICs of greater than or equal to 2 micrograms/ml for ampicillin. PMID:2076596

  10. Antimicrobial susceptibility determined by the E test, Löwenstein-Jensen proportion, and DNA sequencing methods among Mycobacterium tuberculosis isolates discrepancies, preliminary results

    Directory of Open Access Journals (Sweden)

    Maria Inês Moura Freixo

    2004-02-01

    Full Text Available Mycobacterium tuberculosis strains resistant to streptomycin (SM, isoniazid (INH, and/or rifampin (RIF as determined by the conventional Löwenstein-Jensen proportion method (LJPM were compared with the E test, a minimum inhibitory concentration susceptibility method. Discrepant isolates were further evaluated by BACTEC and by DNA sequence analyses for mutations in genes most often associated with resistance to these drugs (rpsL, katG, inhA, and rpoB. Preliminary discordant E test results were seen in 75% of isolates resistant to SM and in 11% to INH. Discordance improved for these two drugs (63% for SM and none for INH when isolates were re-tested but worsened for RIF (30%. Despite good agreement between phenotypic results and sequencing analyses, wild type profiles were detected on resistant strains mainly for SM and INH. It should be aware that susceptible isolates according to molecular methods might contain other mechanisms of resistance. Although reproducibility of the LJPM susceptibility method has been established, variable E test results for some M. tuberculosis isolates poses questions regarding its reproducibility particularly the impact of E test performance which may vary among laboratories despite adherence to recommended protocols. Further studies must be done to enlarge the evaluated samples and looked possible mutations outside of the hot spot sequenced gene among discrepant strains.

  11. Effect of incubation conditions on anaerobic susceptibility testing results.

    OpenAIRE

    Murray, P R; Niles, A C

    1982-01-01

    We determined the effect of performing antimicrobial susceptibility tests in five different anaerobic incubation systems: GasPak jar, large GasPak jar, evacuated-gassed anaerobic jar, anaerobic chamber, and Bio-Bag. Growth of the anaerobes was equivalent in all five incubation systems. The results of testing 38 anaerobes against 11 antimicrobial agents were comparable for the anaerobic jars and anaerobic chamber. However, discordant results were observed for metronidazole and cefamandole test...

  12. Prevalence and Antimicrobial Susceptibility of Coagulase-Negative Staphylococci isolated from Bovine Mastitis

    Directory of Open Access Journals (Sweden)

    Kaliwal B.B.

    2011-08-01

    Full Text Available The study was carried out to investigate the prevalence and antimicrobial susceptibility of Coagulase-Negative Staphylococci isolated from Bovine Mastitis in and around Dharwad region. A total of 310 samples were screened and 180 confirmed Coagulase-Negative Staphylococci were obtained. The antimicrobial susceptibility of Coagulase-Negative Staphylococci against 10 antimicrobial agents was tested using the disc diffusion method. The highest numbers of Coagulase-Negative Staphylococci were susceptible to ceftriaxone 83.88% followed by cefotaxime 79.41%, methicillin 76.47%, ciprofloxacin 73.52%, erythromycin 70.05%, amikacin 66.11%, gentamycin 42.94%, amoxicillin 36.76%, ampicillin 29.41%, and the lowest susceptibility was shown in penicillin 23.23% . The results indicated that the increase in prevalence and antibiotic resistance pattern of the Coagulase-Negative Staphylococci isolated from bovine mastitis exhibited the highest degree of susceptible to ceftriaxone of all the tested antimicrobial agents. [Vet. World 2011; 4(4.000: 158-161

  13. [Antimicrobial susceptibility of Neisseria gonorrhoeae strains determined by disk diffusion].

    Science.gov (United States)

    Llanes Caballero, R; Acosta Giraldo, J C; Sosa Puente, J; Guzmán Hernández, D; Gutiérrez González, O; Llop Hernández, A

    1999-01-01

    The Gonoccocus Laboratory of "Pedro Kourí" Tropical Medicine Institute carried out a study of in vitro susceptibility of Neisseria gonorrhoeae to penicillin, tetracycline, cefuroxime ceftriaxone, cefotaxine and ciprofoxacin by means of a disk diffusion method with the culture medium agar base GC plus supplement. In the first phase, the method was standardized and the reference N. gonorrhoeae ATCC 49226 strain was used whereas in the second phase, 50 gonococcal strains isolated in 8 provinces during 1995 and 1996 were examined. The results of such standardization confirmed that the antimicrobial susceptibility values were within the allowable limits. 52 and 34% of strains were resistant to penicillin and tetracycline respectively and all of them showed susceptibility to the rest of evaluated antimicrobial drugs. We recommend the use of the disk diffusion method for surveillance of gonococci resistance to these drugs in our country. PMID:10887570

  14. Susceptibility of different bacterial species isolated from food animals to copper sulphate, zinc chloride and antimicrobial substances used for disinfection

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Hasman, Henrik

    2004-01-01

    showed that Danish bacterial isolates from livestock so far have not or have only to a limited degree developed resistance to antimicrobial compounds commonly used for disinfection. Acquired copper resistance was only found in enterococci. There were large differences in the intrinsic susceptibility of...... susceptibilities to the different antimicrobial agents. Large variations were observed in the susceptibility of the different bacterial species to the different compounds. Staphylococci were in general very susceptible to all antimicrobial compounds tested. The Salmonella isolates were in general less susceptible......A total of 569 different bacterial isolates (156 Salmonella, 202 E. coli, 43 S. aureus, 38 S. hyicus, 52 E. faecalis, 78 E faecium) were tested for susceptibility to copper sulphate, benzalkonium chloride, hydrogen peroxide and chlorhexidine using MIC determinations. A total of 442 isolates were...

  15. Urinary tract infections: etiology and antimicrobial susceptibility of uropathogens

    Directory of Open Access Journals (Sweden)

    Mario Laneve

    2009-03-01

    Full Text Available Background: Urinary tract infections are a serious health problem affecting millions of people each year.They are the second most common type of infection in the body.The objective of study was to determine the etiology and antimicrobial susceptibility patterns of urinary tract infections pathogens isolated in our Patology Clinic laboratory. Materials and Methods: During the period July 2007- July 2008,were analysed 1422 urine samples.The determination of the total microbe load were acquire with an kit of the BIO-DETECTOR while the identification of germs with Apy sistem. Antibiotic susceptibility tests were assaied with the ATB UR strip. Results: About the total of samples analysed, 320 (22% had significant bacteriuria. Escherichia coli was the most common etiologic agent isolated (62%, followed by Klebsiella ssp. (10%, Pseudomonas aeruginosa (5,95% and Proteus mirabilis (5%. Gram-positive bacteria accounted for only 7.32% , with prevalence of Staphylococcus ssp (5,32 and Enterococcus spp (2%. The most effective antibiotics for Gram- were: Imipenem, Amikacin, Ceftazidime and Cefotaxim, while for Gram+ were: Minocyclin,Vancomycin and Oxacillin. Conclusion: Escherichia coli was the microrganism more frequently isolated between Gram negative bacteria with very susceptible to Amoxicillin. Currently, the empirical use of Cotrimoxazole and Amoxicillin is not recommended for Enterobacteriaceae. Urinary tract infections are more common in women than in men. Men are more likely to get a UTI once past the age of 65. Current data on the prevalence of multidrug resistance among urinary tract isolates should be a consideration to change the current empiric treatment of IVU.

  16. Influence of Clinical Breakpoint Changes from CLSI 2009 to EUCAST 2011 Antimicrobial Susceptibility Testing Guidelines on Multidrug Resistance Rates of Gram-Negative Rods

    OpenAIRE

    Hombach, Michael; Wolfensberger, Aline; Stefan P Kuster; Böttger, Erik C.

    2013-01-01

    Multidrug resistance (MDR) rates of Gram-negative rods were analyzed comparing CLSI 2009 and EUCAST 2011 antibiotic susceptibility testing guidelines. After EUCAST 2011 was applied, the MDR rates increased for Klebsiella pneumoniae (2.2%), Enterobacter cloacae (1.1%), Pseudomonas aeruginosa (0.7%), and Escherichia coli (0.4%). A total of 24% of Enterobacteriaceae MDR isolates and 12% of P. aeruginosa MDR isolates were categorized as MDR due to breakpoint changes.

  17. Antimicrobial Susceptibility Pattern of Enterococci Isolated From Patients in Tehran

    Directory of Open Access Journals (Sweden)

    Saderi

    2015-11-01

    Full Text Available Background Enterococci are one of the most common nosocomial pathogens and the emergence of multidrug-resistant strains has been increasing. Objectives We studied the antimicrobial susceptibility of enterococci isolated from different clinical specimens of patients in Tehran. Materials and Methods From the beginning of April 2013 to the end of June 2013, a total of 146 enterococci were isolated from the Pars General Hospital in Tehran. The antimicrobial susceptibility pattern of the isolates against ampicillin, clindamaycin, ciprofloxacin, erythromycin, levofloxacin, linezolid, nitrofurantoin, tetracycline, and vancomycin was determined using the disk diffusion method according to the guidelines of clinical laboratory standards institute (CLSI. Results The rates of resistance were high to clindamycin, tetracycline, and erythromycin (97.2%, 89%, and 74.5%, respectively; moderate to ciprofloxacilin and levofloxacilin (40.6% and 36.4%, respectively; and low to ampicillin and nitrofurantoin (13.8% and 3.5%, respectively. All isolates were linezolid sensitive. Vancomycin-resistant enterococci (VRE accounted for 9.6% of the isolates. Conclusions VRE and a high rate of resistance to some of antimicrobial agents were found among the enterococci isolated from patients in Tehran. These findings highlight the importance of regular supervision of antimicrobial susceptibilities.

  18. Antimicrobial susceptibility patterns of Streptococcus pneumoniae over 6 years at Gondar University Hospital, Northwest Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Belay Anagaw; Chandrashekhar Unakal; Mucheye Gezachew; Fantahun Biadgelgene; Berhanu Anagaw; Tariku Geleshe; Birke Taddese; Birhanu Getie; Mengistu Endris; Andargachew Mulu

    2013-01-01

    Objective:To assess the magnitude and antimicrobial susceptibility patterns of Streptococcus pneumoniae isolates from various clinical specimens. Methods:A record based on retrospective study was conducted at Gondar University Teaching Hospital from September 2007 to January 2012. All patients who visited Gondar University Hospital and provided clinical specimens (body fluids, discharge, swab and blood) for routine bacteriological culturing and antimicrobial susceptibility testing were taken for analysis. Clinical specimens were processed for bacterial culture according to the standard procedures. Antimicrobial susceptibility test for isolated organisms was done using agar disk diffusion method. The data were entered and analyzed using SPSS software version 16 package. Results: One hundred and fifty three Streptococcus pneumoniae were isolated from patients who visited Gondar University Teaching Hospital bacteriology laboratory for culture. Majority of the pneumococcal isolates were from inpatients [111(72.5%)], and 74(48.4%) were from body fluids. Out of the total isolates, 93(61%) were found to be resistant to at least one antibiotic used for susceptibility testing. Forty eight (43.2%) of the isolates were multi-drug resistant (resistant to two or more drugs). The resistance rate noted for both ciprofloxacin 17(11.1%) and ceftriaxone 15(9.8%) were alarming. Conclusions: High proportions of the isolates tend to be increasingly resistant to the commonly prescribed drugs. The recommended drug of choice like ciprofloxacin and ceftriaxone were found to be less susceptible in the study area. Based on the findings, we therefore recommend that antimicrobial agents should be inspected for acceptable activity before they are prescribed and administered empirically. Further study with a better design and survey of antimicrobial susceptibility at large scale shoule be performed to draw advanced information.

  19. Antimicrobial susceptibility among clinical Nocardia species identified by multilocus sequence analysis.

    Science.gov (United States)

    McTaggart, Lisa R; Doucet, Jennifer; Witkowska, Maria; Richardson, Susan E

    2015-01-01

    Antimicrobial susceptibility patterns of 112 clinical isolates, 28 type strains, and 9 reference strains of Nocardia were determined using the Sensititre Rapmyco microdilution panel (Thermo Fisher, Inc.). Isolates were identified by highly discriminatory multilocus sequence analysis and were chosen to represent the diversity of species recovered from clinical specimens in Ontario, Canada. Susceptibility to the most commonly used drug, trimethoprim-sulfamethoxazole, was observed in 97% of isolates. Linezolid and amikacin were also highly effective; 100% and 99% of all isolates demonstrated a susceptible phenotype. For the remaining antimicrobials, resistance was species specific with isolates of Nocardia otitidiscaviarum, N. brasiliensis, N. abscessus complex, N. nova complex, N. transvalensis complex, N. farcinica, and N. cyriacigeorgica displaying the traditional characteristic drug pattern types. In addition, the antimicrobial susceptibility profiles of a variety of rarely encountered species isolated from clinical specimens are reported for the first time and were categorized into four additional drug pattern types. Finally, MICs for the control strains N. nova ATCC BAA-2227, N. asteroides ATCC 19247(T), and N. farcinica ATCC 23826 were robustly determined to demonstrate method reproducibility and suitability of the commercial Sensititre Rapmyco panel for antimicrobial susceptibility testing of Nocardia spp. isolated from clinical specimens. The reported values will facilitate quality control and standardization among laboratories. PMID:25348540

  20. Trends in Antimicrobial Susceptibilities among Enterobacteriaceae Isolated from Hospitalized Patients in the United States from 1998 to 2001

    OpenAIRE

    Karlowsky, James A.; Jones, Mark E.; Thornsberry, Clyde; Friedland, Ian R.; Sahm, Daniel F.

    2003-01-01

    Longitudinal surveillance of Enterobacteriaceae for antimicrobial susceptibility is important because species of this family are among the most significant and prevalent human pathogens. To estimate rates of in vitro antimicrobial susceptibility among hospitalized patients in the United States, data from The Surveillance Network were studied for 14 agents tested against 10 species of Enterobacteriaceae (n = 384,279) isolated from intensive-care-unit (ICU) patients and non-ICU inpatients from ...

  1. Molecular Characterization and Antimicrobial Susceptibility of Fluoroquinolone-Resistant or -Susceptible Streptococcus pneumoniae from Hong Kong

    OpenAIRE

    Morrissey, Ian; Farrell, David J.; Bakker, Sarah; Buckridge, Sylvie; Felmingham, David

    2003-01-01

    Fluoroquinolone resistance in Streptococcus pneumoniae isolated from Hong Kong as part of Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin 1999/2000 was found to be due to the spread of the Spain23F-1 clone (mainly a Spain23F-1-14 variant). All the isolates were multidrug resistant but were susceptible to quinupristin-dalfopristin, linezolid, and telithromycin. The Spain23F-1 clone also occurred among antimicrobial-susceptible isolates, which suggests th...

  2. Antimicrobial Susceptibilities of Unique Stenotrophomonas maltophilia Clinical Strains

    Science.gov (United States)

    Valdezate, Sylvia; Vindel, Ana; Loza, Elena; Baquero, Fernando; Cantón, Rafael

    2001-01-01

    Susceptibility to 41 antimicrobials was studied with 99 Stenotrophomonas maltophilia strains, and different pulsed-field gel electrophoresis profiles were identified among 130 prospectively collected isolates. Moxalactam, doxycycline, minocycline, and clinafloxacin displayed the highest activity (≥98% susceptibility). Ticarcillin resistance (75%) was reverted by clavulanate in 25% of strains. Trimethoprim-sulfamethoxazole resistance was 26.2% (≥4 [trimethoprim]/76 [sulfamethoxazole] μg/ml) and dropped to 11.1% when an 8/152-μg/ml breakpoint was applied based on its bimodal MIC distribution. Resistance was lower when unique strains were considered, because clonal organisms contribute to resistance. PMID:11302834

  3. Antimicrobial drug susceptibility of Neisseria meningitidis strains isolated from carriers

    Directory of Open Access Journals (Sweden)

    Dayamí García

    2000-06-01

    Full Text Available When it is necessary to determine the susceptibility of Neisseria meningitidis (Nm strains to antimicrobial drugs, it is important to consider that it should be analyzed in a double context. One of them related to the use of drugs in a specific medical treatment; and the other; to chemoprophylatic drugs, both with the same purpose: the accurate selection of the “in vivo” antimicrobial agent. This requires the study of the sensitivity and resistance of strains isolated in both carriers and patients. With the aim of further studying the behavior of the strains that currently circulate in Cuba, an antimicrobial drug susceptibility study was conducted in 90 strains isolated from carriers during the first half of 1998. The agar dilution method was used to determine the minimum inhibitory concentrations (MICs to: penicillin, ampicillin, rifampin, sulfadiazine, chloramphenicol, ciprofloxacin, ceftriaxone, cefotaxime. The study of the three latter drugs was done for the first time in our country. The search for β- lactamase-producer strains was also performed. There was a predominance of penicillin sensitive strains (82,2% with an intermediate sensitivity to ampicillin (57,8%, while 70% of the strains were sensitive to sulfadiazine. Regarding the rest of the antimicrobial drugs, 100% of the strains were sensitive. The paper shows the MICs for each drug as well as the phenotypic characteristics of the strains with the penicillin and sulfadiazine sensitivity and resistance patterns. No β-lactamase-producer strains were found.

  4. Antimicrobial Susceptibility Pattern in Diabetic Foot Ulcer: A Pilot Study

    OpenAIRE

    Sekhar, SM; N Vyas; Unnikrishnan, MK; Rodrigues, GS; Mukhopadhyay, C

    2014-01-01

    Background: Diabetic foot infections (DFIs) are major public health problems and knowledge of microbes that cause infections are helpful to determine proper antibiotic therapy. Aims: The aim was to investigate the antimicrobial susceptibility pattern of microbes in DFIs. Subjects and Methods: A cross-sectional study was conducted for a period of 6 months at the Department of General Surgery, KMC hospital, Manipal University, Manipal, India. During this period, 108 patients having DFIs admitte...

  5. Antimicrobial susceptibilities of Stomatococcus mucilaginosus and of Micrococcus spp.

    OpenAIRE

    von Eiff, C; Herrmann, M; Peters, G.

    1995-01-01

    The in vitro susceptibilities of 63 isolates of Stomatococcus mucilaginosus and of 188 isolates of Micrococcus spp. to 18 antimicrobial agents were determined by the agar dilution method. Many beta-lactams, imipenem, rifampin, and the glycopeptides were shown to be active in vitro against Stomatococcus and Micrococcus isolates, whereas the activities of antibiotics such as some aminoglycosides, erythromycin, and fosfomycin against an important number of these microorganisms are limited.

  6. Antimicrobial susceptibility of Haemophilus parasuis and Histophilus somni from pigs and cattle in Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Seyfarth, Anne Mette; Angen, Øystein

    2004-01-01

    A total of 52 Haemophilus parasuis and 80 Histophilus somni isolates were tested for antimicrobial susceptibility by MIC-determinations. None of the isolates were resistant to ampicillin, ceftiofur, ciprofloxacin, erythromycin, florphenicol, penicillin, spectinomycin, tetracycline, tiamulin, or...... tilmicosin. Two H. parasuis isolates were resistant to trimethoprim + sulfamethoxazole. Six H. parasuis isolates had reduced susceptibility (0.06-0.5 mug/ml) to ciprofloxacin and 10 reduced susceptibility to TMP + sulfamethoxazole (1-2 mug/ml). This study showed that Danish isolates of H. parasuis and H...

  7. Microbiological study and antimicrobial susceptibilities of brucella isolates in serologic diagnosed cases

    Directory of Open Access Journals (Sweden)

    Abtin Heidarzadeh

    2009-01-01

    Full Text Available (Received 25 Nov, 2008 ; Accepted 4 Mar, 2009AbstractBackground and purpose: Brucellosis is a zoonotic disease with worldwide distribution that is endemic in Iran. Worldwide, brucellosis remains a major cause of morbidity in humans and domesticated animals. The disease has a wide spectrum of clinical manifestation and can affect a variety of organs and systems. This study focused on blood culture of serologic diagnosed brucellosis and antimicrobial susceptibility test.Materials and methods: In this cross sectional study, microbiologic survey was done on a total of 30 serum samples with STA titer of 1:160 or greater and 2ME titer of 1:40 or greater, which were presumptive for brucellosis. Blood cultures were done by lysis centrifugation and antimicrobial susceptibility test, against 9 antimicrobial agents by disk method. The data was analyzed by stata V8.0 software.Results: At the end this study, the blood culture isolation rate was 23.3 %( 7 cases out of 30 patients and all of the isolates were brucella melitensis. Antimicrobial susceptibility tests showed high in vitro activity of ofloxacin, ciprofloxacin and doxycycline and also, low in vitro activity of streptomycin and cotrimoxazole.Conclusion: Brucellosis is endemic in Iran. Brucella melitensis was the most common strain of brucella in our patients. Except cotrimoxazole and streptomycin, high in vitro activity was found with other antibrucella agents, especially with ofloxacin, ciprofloxacin and doxycycline. J Mazand Univ Med Sci 2009; 19(68: 74-78 (Persian

  8. In vitro antimicrobial susceptibility of Mycoplasma bovis clinical isolates recovered from bison (Bison bison).

    Science.gov (United States)

    Suleman, Muhammad; Prysliak, Tracy; Windeyer, Claire; Perez-Casal, Jose

    2016-03-01

    Mycoplasma bovis is a pathogen globally affecting cattle and bison herds, causing pneumonia, arthritis, mastitis, abortions, and other symptoms, leading to huge economic losses. Many studies have been done regarding the antimicrobial susceptibility of M. bovis isolated from cattle, but no such study is available for isolates recovered from bison. For the first time, in vitro susceptibilities of 40 M. bovis clinical isolates collected from bison herds in Canada are reported here. Minimal inhibitory concentration (MIC) values were determined using Sensititre® plates. The most effective MIC50 and MIC90 were for spectinomycin (1 and >64 μg/mL), tiamulin (1 and >32 μg/mL), and tulathromycin (16 and 64 μg/mL), whereas tetracyclines, fluoroquinolones, and florfenicol failed to inhibit growth of M. bovis bison isolates. Isolates were nonsusceptible to tetracyclines (100%), fluoroquinolones (97.5%), and tilmicosin (100%), whereas the highest susceptibility of bison clinical isolates was seen with spectinomycin (95%) and tulathromycin (67.5%). Two lung isolates (Mb283 and 348) were found resistant to both spectinomycin and tulathromycin. These results show a marked difference in antimicrobial susceptibility of bison isolates as compared with previously reported and laboratory reference cattle isolates, emphasizing the necessity of testing antimicrobial susceptibility of M. bovis bison isolates and to generate better therapeutic regime for improved recovery chances for infected bison herds across North America. PMID:26854525

  9. Susceptibility testing of Entamoeba histolytica

    International Nuclear Information System (INIS)

    The growth of Entamoeba histolytica in microtiter plates in vitro in a variety of environments with reduced oxygen tensions is reported. With 3% O2, 3% CO2, and 94% N2, the parasite growth in microtiter plates was identical to that in screw-capped culture tubes, as measured by [3H]thymidine incorporation and by quantitative parasite counts. There were no significant differences between the drug concentrations necessary to inhibit parasite growth by 50% based on [3H]thymidine incorporation vs those defined by quantitative parasite counts for the 15 antimicrobial agents tested (including seven drugs used for the treatment of amebiasis). This technique provides a reproducible method to quantitate the activity of potential antiamebic agents in vitro. The isotopic method should be of particular value in defining the metabolism of the parasite and effects of antimicrobial agents on it, whereas the morphologic method may be more valuable for workers with limited resources available to them

  10. Salmonella enterica Serotype Bredeney: Antimicrobial Susceptibility and Molecular Diversity of Isolates from Ireland and Northern Ireland

    OpenAIRE

    Cormican, Martin; DeLappe, Niall; O’Hare, Colette; Doran, Geraldine; Morris, Dearbhaile; Corbett-Feeney, Geraldine; Fanning, Séamus; Daly, Mairead; Fitzgerald, Margaret; Moore, John

    2002-01-01

    Salmonella enterica serotype Bredeney has emerged as the third most commonly identified serotype among human clinical isolates referred to the Irish National Salmonella Reference Laboratory in the years 1998 to 2000. A collection of 112 isolates of S. enterica serotype Bredeney collected during the period 1995 to 1999 from animal, food, and human sources from both Ireland and Northern Ireland were studied. Antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), and DNA ...

  11. Antimicrobial Susceptibility of Bordetella bronchiseptica Isolates from Swine and Companion Animals and Detection of Resistance Genes.

    Directory of Open Access Journals (Sweden)

    Sandra Prüller

    Full Text Available Bordetella bronchiseptica causes infections of the respiratory tract in swine and other mammals and is a precursor for secondary infections with Pasteurella multocida. Treatment of B. bronchiseptica infections is conducted primarily with antimicrobial agents. Therefore it is essential to get an overview of the susceptibility status of these bacteria. The aim of this study was to comparatively analyse broth microdilution susceptibility testing according to CLSI recommendations with an incubation time of 16 to 20 hours and a longer incubation time of 24 hours, as recently proposed to obtain more homogenous MICs. Susceptibility testing against a panel of 22 antimicrobial agents and two fixed combinations was performed with 107 porcine isolates from different farms and regions in Germany and 43 isolates obtained from companion animals in Germany and other European countries. Isolates with increased MICs were investigated by PCR assays for the presence of resistance genes. For ampicillin, all 107 porcine isolates were classified as resistant, whereas only a single isolate was resistant to florfenicol. All isolates obtained from companion animals showed elevated MICs for β-lactam antibiotics and demonstrated an overall low susceptibility to cephalosporines. Extension of the incubation time resulted in 1-2 dilution steps higher MIC50 values of porcine isolates for seven antimicrobial agents tested, while isolates from companion animals exhibited twofold higher MIC50/90 values only for tetracycline and cefotaxime. For three antimicrobial agents, lower MIC50 and MIC90 values were detected for both, porcine and companion animal isolates. Among the 150 isolates tested, the resistance genes blaBOR-1 (n = 147, blaOXA-2, (n = 4, strA and strB (n = 17, sul1 (n = 10, sul2 (n = 73, dfrA7 (n = 3 and tet(A (n = 8 were detected and a plasmid localisation was identified for several of the resistance genes.

  12. Antimicrobial susceptibility of Acinetobacter clinical isolates and emerging antibiogram trends for nosocomial infection management

    Directory of Open Access Journals (Sweden)

    Muhammad Sohail

    2016-06-01

    Full Text Available Abstract: Introduction: The drug resistant Acinetobacter strains are important causes of nosocomial infections that are difficult to control and treat. This study aimed to determine the antimicrobial susceptibility patterns of Acinetobacter strains isolated from different clinical specimens obtained from patients belonging to different age groups. METHODS: In total, 716 non-duplicate Acinetobacter isolates were collected from the infected patients admitted to tertiary-care hospitals at Lahore, Pakistan, over a period of 28 months. The Acinetobacter isolates were identified using API 20E, and antimicrobial susceptibility testing was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI guidelines. RESULTS: The isolation rate of Acinetobacter was high from the respiratory specimens, followed by wound samples. Antibiotic susceptibility analyses of the isolates revealed that the resistance to cefotaxime and ceftazidime was the most common, in 710 (99.2% specimens each, followed by the resistance to gentamicin in 670 (93.6% isolates, and to imipenem in 651 (90.9% isolates. However, almost all isolates were susceptible to tigecycline, colistin, and polymyxin B. CONCLUSIONS: The present study showed the alarming trends of resistance of Acinetobacter strains isolated from clinical specimens to the various classes of antimicrobials. The improvement of microbiological techniques for earlier and more accurate identification of bacteria is necessary for the selection of appropriate treatments.

  13. Antimicrobial resistance in methicillin susceptible and methicillin resistant Staphylococcus pseudintermedius of canine origin

    DEFF Research Database (Denmark)

    Moodley, Arshnee; Damborg, Peter Panduro; Nielsen, Søren Saxmose

    2014-01-01

    from dogs in 27 countries between 1980 and 2013. Resistance to the most common antimicrobials tested for in published studies and important for the treatment of staphylococcal infections in dogs were assessed separately for methicillin resistant (MRSP) and methicillin susceptible (MSSP) isolates...... are collected and presented in a more harmonized way to allow more precise comparison of susceptibility patterns between studies. One way to accomplish this would be through systematic surveillance either at the country-level or at a larger scale across countries e.g. EU level....

  14. Performance of the Vitek 2 system software version 5.03 in the bacterial identification and antimicrobial susceptibility test: evaluation study of clinical and reference strains of Gram-positive cocci

    Directory of Open Access Journals (Sweden)

    Thiago Galvão da Silva Paim

    2014-06-01

    Full Text Available Introduction. The genera Enterococcus, Staphylococcus and Streptococcus are recognized as important Gram-positive human pathogens. The aim of this study was to evaluate the performance of Vitek 2 in identifying Gram-positive cocci and their antimicrobial susceptibilities. Methods. One hundred four isolates were analyzed to determine the accuracy of the automated system for identifying the bacteria and their susceptibility to oxacillin and vancomycin. Results. The system correctly identified 77.9% and 97.1% of the isolates at the species and genus levels, respectively. Additionally, 81.8% of the Vitek 2 results agreed with the known antimicrobial susceptibility profiles. Conclusion. Vitek 2 correctly identified the commonly isolated strains; however, the limitations of the method may lead to ambiguous findings.

  15. Susceptibilities of Neisseria gonorrhoeae to fluoroquinolones and other antimicrobial agents in Hyogo and Osaka, Japan

    OpenAIRE

    Shigemura, K; Okada, H.; Shirakawa, T.; Tanaka, K; Arakawa, S.; Kinoshita, S; Gotoh, A; Kamidono, S

    2004-01-01

    Objectives: Decreasing susceptibility of Neisseria gonorrhoeae to fluoroquinolones has been reported in several countries. Knowledge of local N gonorrhoeae susceptibilities to various antimicrobials is important for establishing a rational treatment strategy in each region.

  16. Prevalence and antimicrobial susceptibility of respiratory pathogens in patients with cystic fibrosis

    Directory of Open Access Journals (Sweden)

    Vilma Almeida Paixão

    2010-08-01

    Full Text Available Respiratory infection is very common in patients suffering from cystic fibrosis (CF. However, the antimicrobial resistance rate of isolates from CF patients is not often documented. In this study, 279 respiratory specimens of 146 patients were prospectively collected from July to December 2006. Microbiological cultures and antimicrobial susceptibility tests of the most frequently isolated bacteria were performed. Sputum and oropharyngeal swabs were processed for culture. During the study period, 50% of the patients harbored Staphylococcus aureus, 35% Pseudomonas aeruginosa, 4.7% Haemophilus influenzae. Methicillin resistant S. aureus (MRSA were detected in 8 (6% patients; ESBL and MBL-producing P. aeruginosa were not identified in these patients. The detection of MRSA in CF patients confirms that antimicrobial resistance patterns should be always kept under surveillance. Moreover, hygiene regulations in CF clinics should prevent a further spread of resistant bacterial strains.

  17. Antimicrobial susceptibility of quinupristin/dalfopristin tested against gram-positive cocci from Latin America: results from the Global SMART (GSMART) surveillance study

    OpenAIRE

    Sader Helio S.; Jones Ronald N.; Ballow Charles H.; Biedenbach Douglas J.; Cereda Rosangela F.

    2001-01-01

    Gram-positive cocci are important causes of both nosocomial and community-acquired infections, and antimicrobial resistance among these pathogens has become an important problem worldwide. Since resistance among these organisms can vary substantially by geographic location, we conducted a multicenter surveillance study with isolates from five Latin American countries (15 medical centers). Quinupristin/dalfopristin (formerly RP-59500) is a novel streptogramin combination with focused activity ...

  18. Comparative antimicrobial susceptibility of Listeria monocytogenes, L. innocua, and L. welshimeri.

    Science.gov (United States)

    Davis, Johnnie A; Jackson, Charlene R

    2009-03-01

    The current study compared antimicrobial susceptibility of Listeria innocua, L. welshimeri, and L. monocytogenes isolated from various sources. Antimicrobial susceptibility testing was performed using a microbroth procedure with Sensititre minimum inhibitory concentration plates containing 18 antimicrobials. Resistant isolates were analyzed for the presence of antimicrobial resistance genes using PCR. The majority of L. monocytogenes isolates were resistant to oxacillin (99%, 89/90) and ceftriaxone (72%, 65/90), while few isolates were resistant to clindamycin (21%, 19/90) and ciprofloxacin (2%, 2/90). When selected sources of L. monocytogenes are compared, resistance to ceftriaxone, clindamycin, and oxacillin ranged from 27% to 86%, 7% to 43%, and 96% to 100%, respectively. Resistance to ciprofloxacin (6%, 2/34), quinupristin/dalfopristin (7%, 1/14), and tetracycline (7%, 1/15) was observed with L. monocytogenes isolated from food, animal, and environmental sources, respectively. All L. welshimeri isolates (6/6) were resistant to streptomycin, quinupristin/dalfopristin, ciprofloxacin, rifampin, oxacillin, penicillin, and clindamycin, while most isolates (67%, 4/6) were resistant to trimethoprim/sulfamethoxazole. All L. innocua isolates (4/4) were resistant to oxacillin and penicillin, whereas 75% (3/4) of isolates were resistant to tetracycline, ceftriaxone, and clindamycin. Resistant isolates were negative for aadA, strA-B, sul I-II, penA, vat(A-E), vga(A-B), and vgb(A-B). However, tetM was detected among tetracycline-resistant isolates. L. welshimeri was resistant to more of the tested antimicrobials than the other two Listeria species tested, but resistance was not attributed to selected resistance genes. These data demonstrate the variability in resistance among Listeria species. However, the human pathogen L. monocytogenes appears to be the least resistant among the tested species. PMID:19216646

  19. Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage

    Directory of Open Access Journals (Sweden)

    Ziola Barry

    2009-09-01

    Full Text Available Abstract Background Though important in the context of food microbiology and as potential pathogens in immuno-compromised humans, bacterial isolates belonging to the genus Pediococcus are best known for their association with contamination of ethanol fermentation processes (beer, wine, or fuel ethanol. Use of antimicrobial compounds (e.g., hop-compounds, Penicillin by some industries to combat Pediococcus contaminants is long-standing, yet knowledge about the resistance of pediococci to antimicrobial agents is minimal. Here we examined Pediococcus isolates to determine whether antibiotic resistance is associated with resistance to hops, presence of genes known to correlate with beer spoilage, or with ability to grow in beer. Results Lactic acid bacteria susceptibility test broth medium (LSM used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds. Conclusion Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed.

  20. Changes in antimicrobial susceptibility patterns of Klebsiella pneumoniae, Escherichia coli and Staphylococcus aureus over the past decade

    DEFF Research Database (Denmark)

    Barfod, Toke Seierøe; Wibroe, Elisabeth Arnberg; Braüner, Julie Vestergaard;

    2015-01-01

    INTRODUCTION: Development of antimicrobial resistance is an ongoing and increasing problem. To provide the best possible treatment for patients it is crucial that clinicians are aware of the local antimicrobial susceptibility patterns. The aim of this study was to present an overview of the...... percentage of bacterial isolates that are covered by the most commonly used antibiotics in the area of Copenhagen and to provide clinicians with a practical tool to help chose the right antimicrobial treatment for their patients. METHODS: We conducted a study of all bacteria isolates tested for antimicrobial...... susceptibility at Hvidovre Hospital, Denmark, from 2004 to 2008. Due to a suspected rise in resistance in Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae after this period, updated data for these bacteria are shown for selected antibiotics until 2014. The department receives samples from...

  1. Antimicrobial susceptibilities of Listeria monocytogenes human strains isolated from 1970 to 2008 in Brazil

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    Cristhiane Moura Falavina dos Reis

    2011-04-01

    Full Text Available INTRODUCTION: Listeria monocytogenes is the causative agent of listeriosis, a foodborne illness that affects mainly pregnant women, the elderly and immunocompromised patients. The primary treatment is a combination of ampicillin with an aminoglycoside, in addition to a second-choice drug represented by chloramphenicol, erythromycin, tetracycline and rifampicin. The aim of this study was to analyze the antimicrobial susceptibility profile of strains isolated from human sources in the last four decades. METHODS: Sixty-eight strains were selected from the culture collection of the Laboratory of Bacterial Zoonoses/LABZOO/FIOCRUZ isolated in different regions of Brazil from 1970 to 2008 and primarily isolated from cerebrospinal fluid and blood culture. Susceptibility tests to antimicrobials drugs were evaluated using the criteria established by Soussy using the Kirby-Bauer method and E-Test strips were used to determine the minimum inhibitory concentration (MIC. RESULTS: Among the strains tested, serovar L4b (60.3% was the most prevalent, followed by serovar 1/2a (20.6%, 1/2b (13.2% and the more uncommon serovars 1/2c, 3b and 4ab (5.9%. All strains were susceptible to ampicillin, cephalothin, erythromycin, gentamicin, teicoplanin and vancomycin. Only one strain (1.5% showed resistance to rifampin, and two (3% were resistant to trimethoprim-sulfamethoxazole. MICs with values up to 2μg/ml reinforce the need for microbiological surveillance. CONCLUSIONS: The study demonstrated low prevalence of strains resistant to the antimicrobial drugs indicated in the treatment of human listeriosis. Monitoring antimicrobial resistance profile is still very important to determine adequate treatment, especially in immunocompromised patients.

  2. Susceptibility testing of Entamoeba histolytica

    Energy Technology Data Exchange (ETDEWEB)

    Cedeno, J.R.; Krogstad, D.J.

    1983-12-01

    The growth of Entamoeba histolytica in microtiter plates in vitro in a variety of environments with reduced oxygen tensions is reported. With 3% O/sub 2/, 3% CO/sub 2/, and 94% N/sub 2/, the parasite growth in microtiter plates was identical to that in screw-capped culture tubes, as measured by (/sup 3/H)thymidine incorporation and by quantitative parasite counts. There were no significant differences between the drug concentrations necessary to inhibit parasite growth by 50% based on (/sup 3/H)thymidine incorporation vs those defined by quantitative parasite counts for the 15 antimicrobial agents tested (including seven drugs used for the treatment of amebiasis). This technique provides a reproducible method to quantitate the activity of potential antiamebic agents in vitro. The isotopic method should be of particular value in defining the metabolism of the parasite and effects of antimicrobial agents on it, whereas the morphologic method may be more valuable for workers with limited resources available to them.

  3. Susceptibility of Urinary Tract Bacteria to Newer Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Manjula Mehta

    2016-01-01

    Full Text Available Urinary tract infections (UTIs are among the commonest types of bacterial infections. The antibiotic treatment for UTIs is associated with important medical and economic implications. Many different microorganisms can cause UTIs though the most common pathogens are E. coli and members of family Enterobacteriaceae. The knowledge of etiology and antibiotic resistance pattern of the organisms causing urinary tract infection is essential. The present study was undertaken to evaluate trends of antibiotic susceptibility of commonly isolated uropathogens using newer antimicrobial agents, prulifloxacin, fosfomycin (FOM and doripenem. We conclude that maintaining a record of culture results and the antibiogram may help clinicians to determine the empirical and/or specific treatment based on the antibiogram of the isolate for better therapeutic outcome.

  4. Susceptibility of Urinary Tract Bacteria to Newer Antimicrobial Drugs.

    Science.gov (United States)

    Mehta, Manjula; Sharma, Jyoti; Bhardwaj, Sonia

    2016-03-15

    Urinary tract infections (UTIs) are among the commonest types of bacterial infections. The antibiotic treatment for UTIs is associated with important medical and economic implications. Many different microorganisms can cause UTIs though the most common pathogens are E. coli and members of family Enterobacteriaceae. The knowledge of etiology and antibiotic resistance pattern of the organisms causing urinary tract infection is essential. The present study was undertaken to evaluate trends of antibiotic susceptibility of commonly isolated uropathogens using newer antimicrobial agents, prulifloxacin, fosfomycin (FOM) and doripenem. We conclude that maintaining a record of culture results and the antibiogram may help clinicians to determine the empirical and/or specific treatment based on the antibiogram of the isolate for better therapeutic outcome. PMID:27275323

  5. Standardization of a broth microdilution susceptibility testing method to determine minimum inhibitory concentrations of aquatic bacteria

    DEFF Research Database (Denmark)

    Miller, R.A.; Walker, R.D.; Carson, J.; Coles, M.; Coyne, R.; Dalsgaard, Inger; Gieseker, C.; Hsu, H.M.; Mathers, J.J.; Papapetropoulou, M.; Petty, B.; Teitzel, C.; Reimschuessel, R.

    2005-01-01

    antimicrobial susceptibility testing methods for bacterial isolates from aquatic animal species. QC ranges were established for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 when testing at 22, 28 and 35 degrees C (E. coli only) for 10 different antimicrobial agents...

  6. Antimicrobial resistance in methicillin susceptible and methicillin resistant Staphylococcus pseudintermedius of canine origin: literature review from 1980 to 2013.

    Science.gov (United States)

    Moodley, Arshnee; Damborg, Peter; Nielsen, Søren Saxmose

    2014-07-16

    Staphylococcus pseudintermedius is a commensal and a common opportunistic pathogen causing mainly infections of the integumentary system in dogs. The recent emergence of multidrug-resistant S. pseudintermedius isolates, in particular methicillin-resistant strains (MRSP) is a threat to small animal health and highlights the need for antimicrobial resistance surveillance to detect trends and potentially perform timeous interventions. We systematically reviewed 202 published articles to investigate temporal changes in antimicrobial resistance in clinical and commensal S. pseudintermedius isolated from dogs in 27 countries between 1980 and 2013. Resistance to the most common antimicrobials tested for in published studies and important for the treatment of staphylococcal infections in dogs were assessed separately for methicillin resistant (MRSP) and methicillin susceptible (MSSP) isolates. Stratified by MSSP and MRSP, no significant increases in antimicrobial resistance were observed over time, except for the penicillinase-labile penicillins (penicillin and ampicillin) among MSSP. However, in recent years, a few studies have reported higher-level of resistance to amikacin, gentamicin and enrofloxacin amongst MSSP. The review highlights inconsistencies between studies as a result of several factors, for example the use of different antimicrobial susceptibility testing methods and interpretation criteria. We recommend that data on susceptibility in important companion animal pathogens are collected and presented in a more harmonized way to allow more precise comparison of susceptibility patterns between studies. One way to accomplish this would be through systematic surveillance either at the country-level or at a larger scale across countries e.g. EU level. PMID:24613081

  7. Antimicrobial susceptibility and clarithromycin resistance patterns of Helicobacter pylori clinical isolates in Vietnam.

    Science.gov (United States)

    Quek, Camelia; Pham, Son T; Tran, Kieu T; Pham, Binh T; Huynh, Loc V; Luu, Ngan B L; Le, Thao K T; Quek, Kelly; Pham, Van H

    2016-01-01

    Helicobacter pylori is a gastric pathogen that causes several gastroduodenal disorders such as peptic ulcer disease and gastric cancer.  Eradication efforts of H. pylori are often hampered by antimicrobial resistance in many countries, including Vietnam.  Here, the study aimed to investigate the occurrence of antimicrobial resistance among H. pylori clinical isolates across 13 hospitals in Vietnam.  The study further evaluated the clarithromycin resistance patterns of H. pylori strains.  In order to address the study interests, antimicrobial susceptibility testing, epsilometer test and PCR-based sequencing were performed on a total of 193 strains isolated from patients, including 136 children (3-15 years of age) and 57 adults (19-69 years of age).  Antimicrobial susceptibility testing showed that the overall resistance to amoxicillin, clarithromycin, levofloxacin, metronidazole, and tetracycline was 10.4%, 85.5%, 24.4%, 37.8%, and 23.8% respectively.  The distribution of minimum inhibitory concentrations (MICs) of clarithromycin-resistant strains was 85.5% with MIC >0.5 μg/mL.  The majority of the clarithromycin resistant isolates (135 of 165 subjects) have MICs ranging from 2 μg/mL to 16 μg/mL.  Furthermore, sequencing detection of mutations in 23S rRNA gene revealed that strains resistant and susceptible to clarithromycin contained both A2143G and T2182C mutations.  Of all isolates, eight clarithromycin-resistant isolates (MIC >0.5 μg/mL) had no mutations in the 23S rRNA gene.  Collectively, these results demonstrated that a proportion of clarithromycin-resistant H. pylori strains, which are not related to the 23S rRNA gene mutations, could be potentially related to other mechanisms such as the presence of an efflux pump or polymorphisms in the CYP2C19 gene.  Therefore, the present study suggests that providing susceptibility testing prior to treatment or alternative screening strategies for antimicrobial resistance is important for future clinical

  8. Antimicrobial susceptibility of clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Shi, Z Y; Liu, P Y; Lau, Y; Lin, Y; Hu, B S; Shir J-M

    1996-02-01

    The in-vitro activity of 18 antimicrobial agents alone or in combination against 248 clinical isolates of Acinetobacter baumannii from Taiwan were tested by agar dilution. The MIC90S of ampicillin, amoxicillin, piperacillin, cefuroxime, cefotaxime, ceftriaxone, gentamicin, and amikacin were at least 128 mu g/ml. Ceftazidime, cefepime, sulbactam, clavulanic acid, and tazobactam presented moderate activity with MIC90S of 32, 16, 16, 32, and 32 mu g/ml, respectively. The increased activity of ampicillin/sulbactam, amoxicillin/clavulanic acid, and piperacillin/tazobactam was due to the intrinsic effect of sulbactam, clavulanic acid, and tazobactam, respectively. Imipenem, meropenem, and ciprofloxacin were the most active antimicrobial agents with MIC90S of 1, 1, and 0.5 mu g/ml, respectively. Nineteen isolates (7.7%) were resistant to all aminoglycosides and beta-lactam antibiotics, except carbapenems and ciprofloxacin. We are concerned about the multidrug resistance of A. baumannii in this study. PMID:9147913

  9. Prevalence and antimicrobial susceptibility of thermophilic Campylobacter in organic and conventional broiler flocks

    DEFF Research Database (Denmark)

    Heuer, Ole Eske; Pedersen, Karl; Andersen, J.S.;

    2001-01-01

    and sixty broiler flocks originating from organic, conventional and extensive indoor production farms were investigated for the presence of Campylobacter at the time of slaughter. Campylobacter isolates from a subsample of positive flocks were subjected to susceptibility testing. Campylobacter spp....... were isolated from 100% of organic broiler flocks, from 36.7% of conventional broiler flocks and from 49.2% of extensive indoor broiler flocks. Six of 62 Campylobacter isolates were resistant to one or more of the antimicrobials tested. Conclusions: These results indicate that the special...... characteristics of organic broiler production provide a high prevalence of Campylobacter positive flocks. Antimicrobial resistance was scarce among Campylobacter isolates from all rearing systems. Significance and Impact of the Study: Organic broiler flocks constitute a strong potential for introduction of...

  10. Antimicrobial susceptibility and presence of resistance genes in staphylococci from poultry

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Agersø, Yvonne; Ahrens, Peter;

    2000-01-01

    to ciprofloxacin. Only six (7%) S. aureus isolates and one Staphylococcus saprophyticus were penicillin resistant. Resistance to sulphamethoxazole was observed among 16 (19%) of S. aureus isolates and two coagulase negative staphylococci (CNS). Twenty (24%) of the S. aureus isolates were resistant to erythromycin...... of conventional biochemical testing and 16S rDNA sequencing. The most common species were Staphylococcus aureus (83), Staphylococcus hyicus (11), Staphylococcus xylosus (9) and Staphylococcus cohnii (6). The isolates were susceptible to most antimicrobials tested. A high frequency of S. aureus (30%) was resistant...

  11. Uterine Microbiology and Antimicrobial Susceptibility in Isolated Bacteria from Mares with Fertility Problems

    Directory of Open Access Journals (Sweden)

    Magnusson U

    2003-09-01

    Full Text Available Uterine microbiology and antimicrobial susceptibility was investigated in 239 mares with fertility problems in a prospective study in Sweden. Uterine swab samples were collected with double guarded swabs and transported overnight before being cultured. The Minimum Inhibitory Concentrations (MIC was determined for a panel of antimicrobials. From 152 of the 239 mares at least one bacterial species was isolated, most frequently E. coli (104 isolates, β-haemolytic streptococci (31 and fungi (16. β-haemolytic streptococci were more frequently (p E. coli (p β-haemolytic streptococcal isolates some resistance was noted for 4 of 11 tested antibiotics, however, all isolates were susceptible to the widely used penicillin G. Among E. coli isolates enrofloxacin was the only of the 10 tested antibiotics for which no resistance was noted. Resistance was most commonly noted to cephalothin (39% of the isolates, streptomycin (22%, trimethoprim/sulphamethoxazole (15% and ampicillin (11%. In conclusion, we show that both E. coli and β-haemolytic streptococci are frequently associated with fertility problems in mares and that antimicrobial resistance is a common feature of E. coli but also recognised for β-haemolytic streptococcal uterine isolates.

  12. Antimicrobial susceptibilities of Campylobacter jejuni and Campylobacter coli recovered from organic turkey farms in Germany.

    Science.gov (United States)

    El-Adawy, Hosny; Ahmed, Marwa F E; Hotzel, Helmut; Tomaso, Herbert; Tenhagen, Bernd-Alois; Hartung, Joerg; Neubauer, Heinrich; Hafez, Hafez M

    2015-11-01

    The popularity of food produced from animals kept under an organic regimen has increased in recent years. In Germany, turkey meat consumption has increased. Despite several studies assessing the susceptibility of campylobacters to various antibiotics in poultry, no sufficient data exists regarding the antimicrobial resistance of campylobacters in organic-reared turkeys. This study provides information about antibiotic resistance in Campylobacter isolated from turkeys reared on organic farms in Germany. Ninety-six Campylobacter strains (41 C. jejuni and 55 C. coli) were isolated from different free-range turkey flocks. In vitro antimicrobial sensitivity testing was done using a broth microdilution test, and the presence of resistance genes to antibiotics (ciprofloxacin, tetracycline) was investigated. All Campylobacter isolates from organic turkeys (n = 96) were phenotypically sensitive to gentamicin, erythromycin, streptomycin, and chloramphenicol. In this study, the antibiotic susceptibilities of C. jejuni to ciprofloxacin, tetracycline, and naladixic acid were 56.0%, 51.3%, and 56.0%, respectively. In contrast, 44.0%, 73.0%, and 74.6% of C. coli isolates were resistant to tetracycline, ciprofloxacin, and nalidixic acid, respectively. Replacement of the Thr-86→Ile in the gyrA gene, and the presence of the tet(O) gene were the mainly identified resistance mechanisms against fluoroquinolones and tetracycline, respectively.These results also reinforce the need to develop strategies and implement specific control procedures to reduce the development of antimicrobial resistance. PMID:26371330

  13. Lessons Learned from Surveillance of Antimicrobial Susceptibilities of Pseudomonas aeruginosa at a Large Academic Medical Center

    Directory of Open Access Journals (Sweden)

    Brett H. Heintz

    2010-04-01

    Full Text Available This research report assessed the differences in resistance rates and antimicrobial usage-versus-susceptibility relationships of Pseudomonas aeruginosa found in various hospital patient care areas. A simplified case control study was also performed to identify patient-specific risk factors associated with cefepime-resistant P. aeruginosa isolates. Last, we determined the consequence of combining mucoid and non-mucoid derived antimicrobial susceptibilities of P. aeruginosa into hospital antibiograms. Overall, susceptibility rates remained lower in the intensive care units (ICUs compared to the non-ICU patient care areas, except for cefepime over the last time period. Cefepime utilization and antimicrobial-resistance rates among P. aeruginosa isolates had a significant relationship. Decreased meropenem exposure was associated with lower resistance rates relative to cefepime. Risk factors independently associated with cefepime-resistant P. aeruginosa were structural lung disease, ICU admission, recent third generation cephalosporin use, frequent hospital admission and non-urine isolates. Large and statistically significant differences were observed between non-mucoid and combined percent susceptibility data for aminoglycosides. To control antimicrobial resistance and optimize initial empiric antimicrobial therapy, antimicrobial susceptibility and utilization patterns in specific patient care areas should be monitored and risk factors for antimicrobial resistance should be assessed. Mucoid strains of P. aeruginosa should not be included into antimicrobial susceptibility data as this may underestimate activity of most antipseudomonal agents.

  14. Clinical significance, antimicrobial susceptibility and molecular identification of Nocardia species isolated from children with cystic fibrosis.

    Science.gov (United States)

    Betrán, Ana; Villuendas, M Cruz; Rezusta, Antonio; Pereira, Javier; Revillo, M José; Rodríguez-Nava, Verónica

    2016-01-01

    Nocardia is an opportunistic pathogen that causes respiratory infections in immunocompromised patients. The aim of this study was to analyze the epidemiology, clinical significance and antimicrobial susceptibility of Nocardia species isolated from eight children with cystic fibrosis. The isolated species were identified as Nocardia farcinica, Nocardia transvalensis, Nocardia pneumoniae, Nocardia veterana and Nocardia wallacei. N. farcinica was isolated in three patients and all of them presented lung affectation with a chronic colonization and pneumonia. N. farcinica showed resistance against gentamicin, tobramycin, cefotaxime, but was susceptible to trimethoprim-sulfamethoxazole and amikacin. N. transvalensis, which was isolated from two patients, showed an association with chronic colonization. N. transvalensis was resistant to tobramycin and amikacin, but susceptible to ciprofloxacin, trimethoprim-sulfamethoxazole and cefotaxime. N. veterana, N. pneumoniae and N. wallacei were isolated from three different patients and appeared in transitory lung colonization. N. veterana and N. pneumoniae were susceptible to imipenem, trimethoprim-sulfamethoxazole, amikacin, tobramycin, and cefotaxime. N. wallacei was resistant to amikacin, tobramycin, imipenem, and trimethoprim-sulfamethoxazole and susceptible to ciprofloxacin and cefotaxime. All the isolates were identified up to species level by 16S rRNA gene sequencing. The presence of Nocardia in the sputum of patients with cystic fibrosis is not always an indication of an active infection; therefore, the need for a treatment should be evaluated on an individual basis. The detection of multidrug-resistant species needs molecular identification and susceptibility testing, and should be performed for all Nocardia infections. PMID:27155949

  15. Frequency and Antimicrobial Susceptibility Pattern of Acinetobacter Species Isolated from Pus and Pus Swab Specimens

    International Nuclear Information System (INIS)

    Objective: To evaluate the frequency and antimicrobial susceptibility pattern of Acinetobacter species isolated from pus and pus swab specimens at a tertiary care setting. Study Design: Cross-sectional observational study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from July 2008 to July 2012. Methodology: Data regarding positive culture and antimicrobial sensitivity pattern was retrieved from the pus and pus swab culture records of the Microbiology Department, AFIP, Rawalpindi. Only those pus and pus swab specimens which yielded the growth of Acinetobacter species were included in the study. Results:Out of 2781, 1848 were of pure pus while 933 were pus swab specimens. Out of 2538 culture positive isolates, 276 (10.9 percentage) were identified as Acinetobacterspecies. Among 276 Acinetobacter species, 245 (88.8 percentage) were Acinetobacter baumannii and 31 (11.2 percentage) were Acinetobacter johnsonii. Male/female ratio of the affected patients was 5.6:1. Doxycycline was the most sensitive antibiotic to which 45 percentage of the tested isolates were sensitive. Sensitivity to all other antimicrobials was 15 percentage or less. Conclusion: About 11 percentage of soft tissue and wound infections are caused by Acinetobacter species in our set up particularly in male. Doxycycline was the most sensitive antibiotic. Sensitivity to all other antimicrobials was 15 percentage or less. In vitro sensitivity to carbapenems is very low. (author)

  16. In vitro assessment of the antimicrobial susceptibility of caprine isolates of Mycoplasma mycoides subsp. capri.

    Science.gov (United States)

    Paterna, A; Tatay-Dualde, J; Amores, J; Prats-van der Ham, M; Sánchez, A; de la Fe, C; Contreras, A; Corrales, J C; Gómez-Martín, Á

    2016-08-01

    The minimum inhibitory concentration (MIC) and minimum mycoplasmacidal concentration (MMC) of 17 antimicrobials against 41 Spanish caprine isolates of Mycoplasma mycoides subsp. capri (Mmc) obtained from different specimens (milk, external auricular canal and semen) were determined using a liquid microdilution method. For half of the isolates, the MIC was also estimated for seven of the antimicrobials using an epsilometric test (ET), in order to compare both methods and assess the validity of ET. Mutations in genes gyrA, gyrB, parC and parE conferring fluoroquinolone resistance, which have been recently described in Mmc, were investigated using PCR. The anatomical origin of the isolate had no effect on its antimicrobial susceptibility. Moxifloxacin and doxycycline had the lowest MIC values. The rest of the fluoroquinolones studied (except norfloxacin), together with tylosin and clindamycin, also had low MIC values, although the MMC obtained for clindamycin was higher than for the other antimicrobials. For all the aminoglycosides, spiramycin and erythromycin, a notable level of resistance was observed. The ET was in close agreement with broth microdilution at low MICs, but not at intermediate or high MICs. The analysis of the genomic sequences revealed the presence of an amino acid substitution in codon 83 of the gene gyrA, which has not been described previously in Mmc. PMID:27387734

  17. Etiologic profile and antimicrobial susceptibility of community-acquired urinary tract infection in two Cameroonian towns

    Directory of Open Access Journals (Sweden)

    Akoachere Jane-Francis Tatah

    2012-05-01

    Full Text Available Abstract Background Urinary tract infection (UTI represents one of the most common diseases encountered in community medical practice. In resource poor settings, treatment is usually empiric due to the high cost and long duration required for reporting diagnosis by culture and antibiotic susceptibility testing. With the growing problem of drug resistance knowledge of antibiotic susceptibility pattern is pertinent for successful eradication of invading pathogens. Our study, the first of its kind in Cameroon, analyzed the distribution and antibiotic susceptibility of bacteria causing community-acquired urinary tract infection (CAUTI in two towns (Bamenda and Buea with a large number of young and middle aged persons, to provide data that could guide empiric treatment. Findings We cultured 235 urine specimens and analyzed the antibiotic susceptibility of isolates by the disc diffusion technique. Uropathogens were recovered from 137 (58.3%, with prevalence rates in Buea and Bamenda being 65.9% and 54% respectively. Predominant pathogens were Escherichia coli (31.4%, Klebsiella oxytoca (25.5% and Staphylococcus spp (24.1%. Geographic variation in uropathogen distribution and antibiotic susceptibility was observed, and a significant difference in pathogen distribution with respect to gender. The 20–39 years age group had the highest prevalence of infection. All pathogens isolated were detected in this group. Isolates exhibited low susceptibility to antibiotics tested. Bamenda isolates generally exhibited lower susceptibility compared to those from Buea. Conclusion Regional variation in etiology of CAUTI and antibiotic susceptibility observed in our study emphasizes the need to establish local and national antimicrobial resistance monitoring systems in Cameroon to provide information for the development of CAUTI treatment guidelines.

  18. 3种微生态制剂对抗菌药物的敏感性检测%Susceptibility Testing of Three Kinds of Microecological Preparation to Antimicrobial Agents

    Institute of Scientific and Technical Information of China (English)

    叶玲梅; 蔡咏梅; 陆红云

    2012-01-01

    Objective To detect the susceptibility of frequently - used microecological preparations Tetralogy of Viable Bifidobacterium Tablet, Bacillus Licheniformis Living Bacterial Capsule and Clostridium Butyricum Living Bacterial Tablet to 16 kinds of antimicrobial a-gents. Methods To culture and isolate the tested bacteria from these three kinds of probiotics, and the drug sensitivity testing was performed by using the microorganism analyzer and the drug sensitive slips. Results Tetralogy of Viable Bifidobacterium Tablet was sensitive to all the antimicrobial agents, Bacillus Licheniformis Living Bacterial Capsule was resistant to penicillins, cephalosporins, ery-thromycin and clindamycin with different degrees, but sensitive to aminoglycosides, and quinolones. Clostridium Butyricum Living Bacterial Tablet was resistant to cephalosporins, aminoglycosides and cotrimoxazole, but sensitive to penicillin, erythromycin, clindamycin and quinolones. Conclusion According to drug sensitivity test, Bacillus Licheniformis Living Bacterial Capsule and Clostridium Butyricum Living Bacterial Tablet can be used in combination with the resistant antimicrobial agents. But Tetralogy of Viable Bifidobacterium Tablet has the incompatibility with antibacterial agents and should be avoid the combination use with them, if must together using, the taking time should be stagger.%目的 检测常用微生态制荆双歧杆菌四联活菌片、地衣芽孢杆菌活菌胶囊、酪酸梭菌活菌片对16种抗菌药物的敏感性.方法 从3种微生态制剂中培养并分离供试菌,用微生物鉴定分析仪和药敏纸片进行药物敏感性检测.结果 双歧杆菌四联活菌片对抗菌药物均敏感;地衣芽孢杆菌活菌胶囊对青霉素类、头孢菌素类、红霉素、克林霉素有不同程度的耐药,对氨基苷类、喹诺酮类等抗菌药物敏感;酪酸梭菌活菌片对头孢菌素类、氨基苷类、复方新诺明耐药,对青霉素类、红霉素、克林霉素

  19. UROPATHOGENS AND THEIR ANTIMICROBIAL SUSCEPTIBILITY PATTERN IN A TERTIARY CARE HOSPITAL

    Directory of Open Access Journals (Sweden)

    Yashavanth

    2012-10-01

    Full Text Available ABSTRACT: BACKGROUND: Urinary tract infections (UTI are one of the most common infectious diseases in humans. Antimicrobial drug r esistance is one of the major threats due to wide spread use of inappropriate and empirical antibio tic therapy. The present study highlights the organisms causing UTI and their antimicrobial s usceptibility pattern. MATERIALS AND METHODS: A total number of 1266 urine samples were analysed in a tertiary care hospital. Urine samples were processed by calibrated loop techni que, delivering 0.001 ml of urine and plated on to MacConkey’s and Cysteine Lactose Electr olyte Deficient (CLED agar plates and incubated at 37 0 C overnight. Appropriate biochemical tests were carri ed out to identify the uropathogens. Antimicrobial susceptibility of the iso lates was determined against various antimicrobial agents. RESULTS: Among this, 332(26.22% culture positive isolates w ere identified and their antimicrobial susceptibility pat terns were analysed. Among the culture positive isolates, Escherichia coli (54.21%was the most common pathogen followed by Klebsiella spp (22.89% and Enterococcus spp (6.92%. Majority of these isolates were resistant to Cotrimoxazole, Amoxycillin/ Clavulanic acid, Piperacillin, Norfloxacin, Ciprofloxacin and also to third generation cephalosporins. Escheri chia coli isolates showed good sensitivity towards Amikacin, Piperacillin/ Tazobactum, Nitrofur antoin and Meropenem. Klebsiella isolates showed good sensitivity towards Amikacin, Levofloxa cin, Piperacillin/ Tazobactum and Meropenem. Staphylococcus aureus and Enterococcus spp s howed good response towards Linezolid, Netilmicin, Vancomycin and Teicoplanin. T here is also increase in incidence of Extended Spectrum Beta Lactamase (ESBL production am ong Escherichia coli (65% and Klebsiella spp (55%. Study also showed that females (67.17% are more vulnerable to urinary tract infections than males (32.83%. CONCLUSION: Due to excessive use of

  20. Antimicrobial susceptibility patterns, emm type distribution and genetic diversity of Streptococcus pyogenes recovered in Brazil

    Directory of Open Access Journals (Sweden)

    Glauber P Arêas

    2014-11-01

    Full Text Available Streptococcus pyogenes is responsible for a variety of infectious diseases and immunological complications. In this study, 91 isolates of S. pyogenes recovered from oropharynx secretions were submitted to antimicrobial susceptibility testing, emm typing and pulsed-field gel electrophoresis (PFGE analysis. All isolates were susceptible to ceftriaxone, levofloxacin, penicillin G and vancomycin. Resistance to erythromycin and clindamycin was 15.4%, which is higher than previous reports from this area, while 20.9% of the isolates were not susceptible to tetracycline. The macrolide resistance phenotypes were cMLSB (10 and iMLSB (4. The ermB gene was predominant, followed by the ermA gene. Thirty-two emm types and subtypes were found, but five (emm1, emm4, emm12, emm22, emm81 were detected in 48% of the isolates. Three new emm subtypes were identified (emm1.74, emm58.14, emm76.7. There was a strong association between emm type and PFGE clustering. A variety of PFGE profiles as well as emm types were found among tetracycline and erythromycin-resistant isolates, demonstrating that antimicrobial resistant strains do not result from the expansion of one or a few clones. This study provides epidemiological data that contribute to the development of suitable strategies for the prevention and treatment of such infections in a poorly studied area.

  1. Antimicrobial susceptibility of lactic acid bacteria isolated from Sombor cheese

    Directory of Open Access Journals (Sweden)

    Bulajić Snežana

    2011-01-01

    Full Text Available Extensive literature data pointed out that some lactic acid bacteria (LABs, the predominant microbiota in fermented dairy products, may serve as reservoirs of antibiotic resistance genes potentially transferable to human pathogens. Hence, there is a growing interest in the possible role of Las vectors of antibiotic resistance determinants. This paper reports the susceptibility patterns of a number of Lspecies (belonging to the genera Lactococcus, Lactobacillus, and Enterococcus isolated from different batches of autochthonous Sombor cheese, traditionally made without the addition of starter cultures, and currently proposed as a candidate for PDO/PGI designation. The experimental work was performed to select strains that do not contain antibiotic resistance genes among those with desirable technological characteristics such as rapid acidification, proteolysis, ability to metabolise citrate and form aromogenic compounds. In addition, the results of these screening procedures could also indicate the types and degrees of antimicrobial resistance already present among the Lcommunity of Sombor cheese, which according to their geographically restricted areas of production, specific manufacturing process and characteristic aroma and appearance, represent a distinct ecological niche.

  2. Antimicrobial susceptibility of foodborne pathogens in organic or natural production systems: an overview.

    Science.gov (United States)

    Jacob, Megan E; Fox, James Trent; Reinstein, Shelby L; Nagaraja, T G

    2008-12-01

    Organic and natural food production systems are increasing in popularity, at least partially because consumers perceive that these niche markets provide healthier and safer food products. One major difference between these niche markets and conventional production systems is the use of antimicrobials. Because antimicrobial agents exert selective pressures for antimicrobial resistance, relating antimicrobial susceptibility of foodborne bacteria to niche market production systems is of interest. Other differences between production systems might also influence the susceptibility of foodborne pathogens. The objective of this review is to compare the impact of food animal production systems on the antimicrobial susceptibility of common foodborne bacterial pathogens. Studies comparing the susceptibility of such pathogens were diverse in terms of geographic location, procedures, species of bacteria, and antimicrobials evaluated; thus, it was difficult to draw conclusions. The literature is highly variable in terms of production type and practices and susceptibility associations, although few studies have compared truly organic and conventional practices. When statistical associations were found between production type and minimum inhibitory concentrations or percentage of isolates resistant for a particular pathogen, the isolates from conventionally reared animals/products were more commonly resistant than the comparison group (organic, antibiotic free, etc.). Therefore, further studies are needed to better assess public health consequences of antimicrobial resistance and food animal production systems, specifically organic or natural versus conventional. PMID:18847380

  3. In vitro biofilm formation by uropathogenic Escherichia coliand their antimicrobial susceptibility pattern

    Institute of Scientific and Technical Information of China (English)

    Poovendran Ponnusamy; Vidhya Natarajan; Murugan Sevanan

    2012-01-01

    Objective:To detect in vitro biofilm formation of uropathogenic Escherichia coli(E. coli)(UPEC) strains isolated from urine specimens and also to determine their antimicrobial susceptibility pattern using 13 commonly used antibiotics.Methods: The present study comprised of166 urine specimens collected from tertiary care hospitals in and around Coimbatore, South India. All the specimens were subjected to gram staining, bacterial culture and theE. coli strains were screened for biofilm formation using Tube Method(TM), Congo Red Agar(CRA) and Tissue Culture Plate method(TCP) respectively. Subsequently, the antimicrobial susceptibility test was performed by Kirby Bauer-disk diffusion method for the biofilm and non-biofilm producingE. colistrains.Results: Of the100 (60.2 %)E. coli strains,72 strains displayed a biofilm positive phenotype under the optimized conditions in the Tube Method and the strains were classified as highly positive(17, 23.6%), moderate positive(19, 26.3 %) and weakly positive(36, 50.0 %), similarly under the optimized conditions on Congo Red agar medium, biofilm positive phenotype strains were classified as highly positive(23, 23 %), moderate positive(37, 37 %)and weakly positive (40, 40%). While inTCP method, the biofilm positive phenotype strains were also classified as highly positive(6, 6 %), moderate positive (80, 80 %)and weakly positive(14, 14 %), it didn’t not correlate well with the tube method for detecting biofilm formation in E. coli. The rates of antibiotic resistance of biofilm producingE. coliwere found to be 100 % for chloramphenicol and amoxyclav (amoxicillin and clavulanic acid),86% for gentamicin and cefotaxime,84% for ceftazidime,83% for cotrimoxazole and piperacillin/tazobactam,75% for tetracycline and70% for amikacin.Conclusions: This study reveals the prevalence and antimicrobial susceptibility pattern of biofilm and non-biofilm producing uropathogenic E. coli strains.

  4. Antimicrobial susceptibility profiles of thermophilic campylobacters isolated from patients in the town of Niš

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    Miljković-Selimović Biljana

    2009-01-01

    Full Text Available Background/Aim. In some clinical forms of human Campylobacter infections, such as prolonged diarrhea or associated with postinfections sequels, antibacterial treatment is necessary. The aim of the present study was to evaluate the antimicrobial susceptibility of thermophilic Campylobacter strains isolated from patients with diarrhea, as well as from patients with diarrhea followed by postinfections sequels, to drugs used in the therapy of enterocolitis, and to nalidixic acid used in laboratory identification and differentiation of thermophilic Campylobacter spp. Methods. We studied the antimicrobial susceptibility profiles of 131 Campylobacter strains isolated from patients with diarrhea (122 strains, diarrhea associated with rheumatic disorders (8 strains, and one strain isolated from a patient with Guillain-Barré Syndrome following Campylobacter enterocolitis. Susceptibility testing to erythromycin, gentamicin, tetracycline, chloramphenicol, ciprofloxacin and nalidixic acid was performed by the agar dilution method. Results. In the strains we investigated, resistance to gentamicin and chloramphenicol was not recorded, whereas a low rate of strains resistant to erythromycin (2.4%, a higher prevalence of strains resistant to tetracycline (9.9%, and a high level of resistance to ciprofloxacin (29.8% and nalidixic acid (33.3% were registered. All strains resistant to nalidixic acid were also resistant to ciprofloxacin. In addition, there was no difference in the occurrence of resistance between strains isolated from patients with diarrhea as compared to those isolated from patients with diarrhea followed by postinfection disorders. Conclusion. The fact that the most of Campylobacter strains were sensitive to erythromycin and all to gentamicin, makes erythromycin an antibiotic of choice in the treatment of Campylobacter diarrhea and gentamicin when parenteral therapy should be administered. Resistance to tetracycline and, especially, ciprofloxacin

  5. Stenotrophomonas maltophilia PhoP, a Two-Component Response Regulator, Involved in Antimicrobial Susceptibilities.

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    Ming-Che Liu

    Full Text Available Stenotrophomonas maltophilia, a gram-negative bacterium, has increasingly emerged as an important nosocomial pathogen. It is well-known for resistance to a variety of antimicrobial agents including cationic antimicrobial polypeptides (CAPs. Resistance to polymyxin B, a kind of CAPs, is known to be controlled by the two-component system PhoPQ. To unravel the role of PhoPQ in polymyxin B resistance of S. maltophilia, a phoP mutant was constructed. We found MICs of polymyxin B, chloramphenicol, ampicillin, gentamicin, kanamycin, streptomycin and spectinomycin decreased 2-64 fold in the phoP mutant. Complementation of the phoP mutant by the wild-type phoP gene restored all of the MICs to the wild type levels. Expression of PhoP was shown to be autoregulated and responsive to Mg2+ levels. The polymyxin B and gentamicin killing tests indicated that pretreatment of low Mg2+ can protect the wild-type S. maltophilia from killing but not phoP mutant. Interestingly, we found phoP mutant had a decrease in expression of SmeZ, an efflux transporter protein for aminoglycosides in S. maltophilia. Moreover, phoP mutant showed increased permeability in the cell membrane relative to the wild-type. In summary, we demonstrated the two-component regulator PhoP of S. maltophilia is involved in antimicrobial susceptibilities and low Mg2+ serves as a signal for triggering the pathway. Both the alteration in membrane permeability and downregulation of SmeZ efflux transporter in the phoP mutant contributed to the increased drug susceptibilities of S. maltophilia, in particular for aminoglycosides. This is the first report to describe the role of the Mg2+-sensing PhoP signaling pathway of S. maltophilia in regulation of the SmeZ efflux transporter and in antimicrobial susceptibilities. This study suggests PhoPQ TCS may serve as a target for development of antimicrobial agents against multidrug-resistant S. maltophilia.

  6. Stenotrophomonas maltophilia PhoP, a Two-Component Response Regulator, Involved in Antimicrobial Susceptibilities

    Science.gov (United States)

    Huang, Yi-Wei; Chen, Hsing-Yu; Hsueh, Po-Ren; Lai, Szu-Yu; Chen, Li-Chia; Chou, Yi-Hwa; Lin, Wen-Yuan; Liaw, Shwu-Jen

    2016-01-01

    Stenotrophomonas maltophilia, a gram-negative bacterium, has increasingly emerged as an important nosocomial pathogen. It is well-known for resistance to a variety of antimicrobial agents including cationic antimicrobial polypeptides (CAPs). Resistance to polymyxin B, a kind of CAPs, is known to be controlled by the two-component system PhoPQ. To unravel the role of PhoPQ in polymyxin B resistance of S. maltophilia, a phoP mutant was constructed. We found MICs of polymyxin B, chloramphenicol, ampicillin, gentamicin, kanamycin, streptomycin and spectinomycin decreased 2–64 fold in the phoP mutant. Complementation of the phoP mutant by the wild-type phoP gene restored all of the MICs to the wild type levels. Expression of PhoP was shown to be autoregulated and responsive to Mg2+ levels. The polymyxin B and gentamicin killing tests indicated that pretreatment of low Mg2+ can protect the wild-type S. maltophilia from killing but not phoP mutant. Interestingly, we found phoP mutant had a decrease in expression of SmeZ, an efflux transporter protein for aminoglycosides in S. maltophilia. Moreover, phoP mutant showed increased permeability in the cell membrane relative to the wild-type. In summary, we demonstrated the two-component regulator PhoP of S. maltophilia is involved in antimicrobial susceptibilities and low Mg2+ serves as a signal for triggering the pathway. Both the alteration in membrane permeability and downregulation of SmeZ efflux transporter in the phoP mutant contributed to the increased drug susceptibilities of S. maltophilia, in particular for aminoglycosides. This is the first report to describe the role of the Mg2+-sensing PhoP signaling pathway of S. maltophilia in regulation of the SmeZ efflux transporter and in antimicrobial susceptibilities. This study suggests PhoPQ TCS may serve as a target for development of antimicrobial agents against multidrug-resistant S. maltophilia. PMID:27159404

  7. Stenotrophomonas maltophilia PhoP, a Two-Component Response Regulator, Involved in Antimicrobial Susceptibilities.

    Science.gov (United States)

    Liu, Ming-Che; Tsai, Yi-Lin; Huang, Yi-Wei; Chen, Hsing-Yu; Hsueh, Po-Ren; Lai, Szu-Yu; Chen, Li-Chia; Chou, Yi-Hwa; Lin, Wen-Yuan; Liaw, Shwu-Jen

    2016-01-01

    Stenotrophomonas maltophilia, a gram-negative bacterium, has increasingly emerged as an important nosocomial pathogen. It is well-known for resistance to a variety of antimicrobial agents including cationic antimicrobial polypeptides (CAPs). Resistance to polymyxin B, a kind of CAPs, is known to be controlled by the two-component system PhoPQ. To unravel the role of PhoPQ in polymyxin B resistance of S. maltophilia, a phoP mutant was constructed. We found MICs of polymyxin B, chloramphenicol, ampicillin, gentamicin, kanamycin, streptomycin and spectinomycin decreased 2-64 fold in the phoP mutant. Complementation of the phoP mutant by the wild-type phoP gene restored all of the MICs to the wild type levels. Expression of PhoP was shown to be autoregulated and responsive to Mg2+ levels. The polymyxin B and gentamicin killing tests indicated that pretreatment of low Mg2+ can protect the wild-type S. maltophilia from killing but not phoP mutant. Interestingly, we found phoP mutant had a decrease in expression of SmeZ, an efflux transporter protein for aminoglycosides in S. maltophilia. Moreover, phoP mutant showed increased permeability in the cell membrane relative to the wild-type. In summary, we demonstrated the two-component regulator PhoP of S. maltophilia is involved in antimicrobial susceptibilities and low Mg2+ serves as a signal for triggering the pathway. Both the alteration in membrane permeability and downregulation of SmeZ efflux transporter in the phoP mutant contributed to the increased drug susceptibilities of S. maltophilia, in particular for aminoglycosides. This is the first report to describe the role of the Mg2+-sensing PhoP signaling pathway of S. maltophilia in regulation of the SmeZ efflux transporter and in antimicrobial susceptibilities. This study suggests PhoPQ TCS may serve as a target for development of antimicrobial agents against multidrug-resistant S. maltophilia. PMID:27159404

  8. The Prevalence and Antimicrobial Susceptibility of Bacterial Uropathogens Isolated from Pediatric Patients

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    R Ranjbar

    2009-06-01

    Full Text Available "nBackground: Urinary tract infection (UTI is considered as the most common bacterial infectious disease seen among the pediatric patients. The aim of this study was to investigate the prevalence and antimicrobial susceptibility of bacterial uropathogens isolated from the pediatric patients with urinary tract infections."nMethods: This descriptive study was conducted in Children Medial Center, Tehran, Iran from March 2006 to Feb 2007. Clean-catch midstream urine specimens were obtained from the patients and cultured on the appropriate bacteriological media. Bacterial isolates were identified by standard biochemical and serological tests. Antimicrobial susceptibility testing was performed according to CLSI guidelines."nResults: From 14199 urine specimens, 16.2% had positive results for bacterial cultures. Nine hundred twenty one strains were identified as Escherichia coli; 412 as Klebsiella spp., 285 as Coagulase negative Staphylocococci, 202 as Enterococcus spp., 158 as Pseudomonas spp., and 83 as Staphylococcus aureus. E. coli isolates showed high resistance to carbenicillin (68%, ampicillin (96%, trimethoprim-sulfomethoxazol (70% and kanamycin (65%. More than 30% of isolates of Klebsiella spp., Pseudomonas spp. and Enterobacter spp. have shown high degree of resistance to commonly used antibiotics."nConclusion: Our findings reinforce the need for ongoing investigation to show trends in antibiotic resistance, which can help to prescribing of antibiotics in clinics.

  9. Antimicrobial susceptibility of Clostridium difficile isolated from food animals on farms.

    Science.gov (United States)

    Thitaram, S N; Frank, J F; Siragusa, G R; Bailey, J S; Dargatz, D A; Lombard, J E; Haley, C A; Lyon, S A; Fedorka-Cray, P J

    2016-06-16

    Clostridium difficile is commonly associated with a spectrum of disease in humans referred to as C. difficile-associated disease (CDAD) and use of antimicrobials is considered a risk factor for development of disease in humans. C. difficile can also inhabit healthy food animals and transmission to humans is possible. As a result of the complexity and cost of testing, C. difficile is rarely tested for antimicrobial susceptibility. A total of 376 C. difficile strains (94 each from swine and dairy feces, and 188 from beef cattle feces) were isolated from healthy food animals on farms during studies conducted by the National Animal Health Monitoring System. Using the Etest (AB Biodisk, Solna, Sweden), samples were tested for susceptibility to nine antimicrobials implicated as risk factors for CDAD (linezolid, amoxicillin-clavulanic acid, ampicillin, clindamycin, erythromycin, levofloxacin, metronidazole, rifampicin, and vancomycin). Vancomycin was active against all isolates of C. difficile (MIC90=3.0μg/ml) while almost all isolates (n=369; 98.1%) were resistant to levofloxacin. With the exception of vancomycin, resistance varied by animal species as follows: linezolid (8.5% resistance among swine versus 2.1 and 1.1% resistance among dairy and beef, respectively), clindamycin (56.4% resistance among swine versus 80% and 90.9% resistance among dairy and beef, respectively), and rifampicin (2.1% and 0% resistance among swine and dairy cattle isolates, respectively versus 14.3% resistance among beef isolates). Regardless of species, multiple drug resistance was observed most often to combinations of clindamycin and levofloxacin (n=195; 51.9%) and ampicillin, clindamycin and levofloxacin (n=41; 10.9%). The reason for the variability of resistance between animal species is unknown and requires further research. PMID:27043382

  10. Techniques for anaerobic susceptibility testing.

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    Thornsberry, C

    1977-03-01

    Minimal inhibitory concentrations (MICs) of antimicrobial agents for anaerobic bacteria can be determined by agar dilution and broth dilution (including microdilution) techniques. If MICs are not determined routinely, the disk broth or category methods are recommended for routine use. The Bauer-Kirby disk diffusion method and its interpretative standards should not be used for anaerobes. PMID:850089

  11. Genetic Relatedness, Antimicrobial and Biocide Susceptibility Comparative Analysis of Methicillin-Resistant and -Susceptible Staphylococcus pseudintermedius from Portugal

    OpenAIRE

    Couto, Natacha; Belas, Adriana; Couto, Isabel; Perreten, Vincent; Pomba, Constança

    2014-01-01

    Forty methicillin-resistant and -susceptible Staphylococcus pseudintermedius (MRSP and MSSP, respectively) from colonization and infection in dogs and cats were characterized for clonality, antimicrobial, and biocide susceptibility. MSSP were genetically more diverse than MRSP by multi-locus sequence typing and pulsed-field gel electrophoresis. Three different spa types (t06, t02, t05) and two SCCmec types (II-III and V) were detected in the MRSP isolates. All MRSP and two MSSP strains were m...

  12. Effect of antimicrobial peptides on colistin-susceptible and colistin-resistant strains of Klebsiella pneumoniae and Enterobacter asburiae.

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    Kádár, Béla; Kocsis, Béla; Kristof, Katalin; Tóth, Ákos; Szabó, Dóra

    2015-12-01

    In this study susceptibility to different antimicrobial peptides was investigated on colistin-susceptible and colistin-resistant identical pulsotype strains of KPC-2 producing Klebsiella pneumoniae ST258 as well as colistin-susceptible and colistin-resistant Enterobacter asburiae strains isolated from clinical samples. In our test, bacteria were exposed to 50 mg/ml lactoferrin, lysozyme and protamine - cationic antimicrobial peptides belonging to innate immune system and having structural similarity to polymyxins - in separate reactions. After 18 hours incubation of colonies were counted. 40% of colistin-resistant K. pneumoniae strains and 97% of colistin-susceptible counterpart strains were lysed by protamine whereas 87% and 100% colony forming unit decrease by lysozyme was seen, respectively. In the case of colistin-resistant E. asburiae strains 1 log10 cell count increase were observed after treatment with lysozyme and 1.56 log10 after lactoferrin exposure compared to the initial number whereas the colistin-susceptible showed no relevant cell count increase. Our findings suggest that acquired colistin-resistance in Enterobacteriaceae is associated with tolerance against antimicrobial peptides. PMID:26689883

  13. In vitro susceptibility to antimicrobial drugs of 62 Salmonella strains isolated from horses in The Netherlands.

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    van Duijkeren, E; van Klingeren, B; Vulto, A G; Sloet van Oldruitenborgh-Oosterbaan, M M; Breukink, H J; van Miert, A S

    1995-06-01

    The in vitro activity of 17 antimicrobial drugs against strains of Salmonella typhimurium (n = 52), Salmonella thompson (n = 2), Salmonella heidelberg (n = 3), Salmonella hadar (n = 2), Salmonella enteritidis (n = 1), Salmonella infantis (n = 1) and Salmonella derby (n = 1) was tested using the agar dilution method. The strains were isolated from horses admitted to the Large Animal Clinics of Utrecht University. The majority of strains were susceptible to gentamicin, amikacin, kanamycin, enrofloxacin, ciprofloxacin, flumequine, colistine, furazolidone and ceftiofur. However, all strains of Salmonella typhimurium phage type 200 (n = 14), were multiresistant i.e. were resistant to ampicillin amoxycillin, amoxycillin in combination with clavulanic acid, chloramphenicol, nitrofurantoin, trimethoprim, aditoprim and baquiloprim. Two of these strains were also resistant to gentamicin. Based on the susceptibility data found in the present study in combination with pharmacokinetic data available in the literature a rationale for antimicrobial therapy in equine salmonellosis is given. As first choice, gentamicin at a dosage of 3 mg/kg combined with ampicillin at a dosage of 20 mg/kg given with a 8-12 hour dosing interval by intravenous route is advised. As an alternative, the intravenous administration of trimethoprim/sulfonamide combinations given twice daily at a combined dose of 30 mg/kg is suggested. PMID:7653025

  14. Prevalence and antimicrobial susceptibility of Campylobacter spp. in live and dressed chicken in Jordan.

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    Osaili, Tareq M; Alaboudi, Akram R; Al-Akhras, Rani R

    2012-01-01

    A total of 140 broiler flocks presented for slaughtering at Amman slaughterhouse were tested for Campylobacter spp. via collection of cloacal swabs from live birds, feathered skin samples at prescalding, and skin samples at postscalding (62°C or 57°C scalding temperature), postevisceration, and postchilling. The results indicated that 40% of the flocks tested by cloacal swabs, 34% at prescalding, 32% at post 57°C scalding, and 32% postevisceration were harboring Campylobacter jejuni. None of the skin samples collected from dressed birds at postscalding (62°C) or postwashing-chilling steps (regardless of scalding temperature) revealed the presence of C. jejuni. Thirty eight isolates were tested for susceptibility to ten antimicrobials by using the microbroth dilution method. Almost 50% of the isolates were multidrug resistant to 9 or 10 out of the ten tested antimicrobials. The other half of tested isolates were sensitive to erythromycin, tetracycline, doxycyclin, chlortetracycline, ciprofloxacin, enorfloxacin, gentamycin, tilmicosin, amoxicillin, and trimethoprim. PMID:21988398

  15. Susceptibility testing with the sensititer breakpoint broth microdilution system.

    Science.gov (United States)

    Doern, G V; Dascal, A; Keville, M

    1985-05-01

    The antimicrobial susceptibility profiles of a total of 318 aerobic and facultatively anaerobic bacteria (255 gram-negative bacilli and 63 gram-positive cocci) were determined, using a new commercially available breakpoint broth microdilution procedure (Sensititer Breakpoint System (SBS), Gibco Diagnostics, Inc., Madison, WI) that categorizes test results in the form of susceptibility categories: susceptible, intermediate, and resistant. Results obtained with the SBS were compared with those achieved with a standardized disk diffusion procedure. Among a total of 4,414 organism-antimicrobic comparisons, concordance between the results of the SBS and the disk diffusion procedure was observed in 3,888 cases (88.1%). Four hundred twenty-three (9.6%) minor discrepancies, 45 (1.0%) major discrepancies, and 58 (1.3%) very major discrepancies were noted. Arbitration of major and very major discrepancies with a full-range minimum inhibitory concentration (MIC) procedure confirmed the results of the SBS in 53.4% of cases. A single organism-antimicrobial combination, the nonenterococcal streptococci tested against the aminoglycosides, yielded a significant number of very major errors which were arbitrated in favor of the disk diffusion result. These errors were probably due to poor growth of the test organism in the broth medium used for performing the SBS test (i.e., cation-supplemented Mueller-Hinton broth). With this exception, the SBS was found to be at least as accurate as the standardized disk diffusion procedure. PMID:3922668

  16. Antimicrobial susceptibility of Pseudomonas aeruginosa isolates from dogs with otitis externa.

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    Mekić, S; Matanović, K; Šeol, B

    2011-07-30

    Pseudomonas aeruginosa is a common cause of otitis externa in dogs, and treatment of these infections is becoming problematic because of the increasing number of multiresistant strains. The aim of the present study was to compare the in vitro activities of cefepime, ceftazidime, enrofloxacin, ciprofloxacin, gentamicin and ticarcillin/clavulanic acid against 104 strains of P aeruginosa isolated from dogs with otitis externa. Antimicrobial susceptibility and minimum inhibitory concentrations, in µg/ml, were evaluated by the E test (bioMérieux). The most active compound was ceftazidime, with 100 per cent efficiency. The majority of tested strains were susceptible to ticarcillin/clavulanic acid (89.4 per cent), followed by ciprofloxacin (88.5 per cent) and cefepime (60.6 per cent). The highest resistance was observed to enrofloxacin (51.9 per cent) and gentamicin (43.3 per cent). Large numbers of strains were intermediately susceptible to antibiotics registered for use in veterinary medicine in Croatia--enrofloxacin (47.1 per cent) and gentamicin (41.3 per cent). PMID:21742683

  17. Frequency and Antimicrobial Susceptibility of Coagulasenegative Staphylococci Isolated from Bovine Mastitis in Dairy Farms from Tolima, Colombia

    OpenAIRE

    María del Pilar Sánchez Bonilla; Norma Patricia Gutiérrez Murillo

    2015-01-01

    Objective: To determine the antimicrobial presence and susceptibility of the coagulase-negative staphylococci group (ECN, for its initials in Spanish) in some cattle farms from Tolima, Colombia. Materials and methods: Using the California test for the diagnosis of mastitis (CMT, for its initials in Spanish), 484 quarters belonging to 121 cows from five small production ranches from a region of central Tolima were evaluated. CMT positive samples were cultivated for bacterial isolation. The ECN...

  18. Mycoplasma bovis: Mechanisms of Resistance and Trends in Antimicrobial Susceptibility

    Science.gov (United States)

    Lysnyansky, Inna; Ayling, Roger D.

    2016-01-01

    Mycoplasma bovis is a cell-wall-less bacterium and belongs to the class Mollicutes. It is the most important etiological agent of bovine mycoplasmoses in North America and Europe, causing respiratory disease, mastitis, otitis media, arthritis, and reproductive disease. Clinical disease associated with M. bovis is often chronic, debilitating, and poorly responsive to antimicrobial therapy, resulting in significant economic loss, the full extent of which is difficult to estimate. Until M. bovis vaccines are universally available, sanitary control measures and antimicrobial treatment are the only approaches that can be used in attempts to control M. bovis infections. However, in vitro studies show that many of the current M. bovis isolates circulating in Europe have high minimum inhibitory concentrations (MIC) for many of the commercially available antimicrobials. In this review we summarize the current MIC trends indicating the development of antimicrobial resistance in M. bovis as well as the known molecular mechanisms by which resistance is acquired. PMID:27199926

  19. In Vitro Susceptibility Test of Different Clinical Isolates against Ceftriaxone

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    Syed Hakim Masood

    2010-06-01

    Full Text Available Objectives: Because of the prevailing penicillin resistance in microorganisms, broad spectrum cephalosporins are used empirically specially in developing countries. The aim of this study is to determine the susceptibility pattern of different gram positive and gram negative pathogens against third generation cephalosporin-ceftriaxone to explore the existing effectiveness of this antibiotic.Methods: 180 clinical isolates of different gram positive and gram negative pathogens including P.mirabilis, S. typhi P.aeruginosa, E. coli, S. aureus and Klebsiella were collected from blood and urine samples of in-patients. 30 isolates of all species were tested against each of six brands of ceftriaxone using in vitro sensitivity tests by disc diffusion method (NCCLS criteria. The susceptibility limit was ≥21 mm zone of inhibition, while moderately susceptible was considered at 20-14 mm, and those isolates which showed >13 mm or no zone of inhibition were resistant to this antibacterial drug.Results: Ceftriaxone was found most effective against S. aureus. While 96.1% of the isolates showed susceptibility towards ceftriaxone, followed by E. coli (95%, P. aeruginosa (92.7%, K. pneumonia (89.4% and S. typhi (87.2%. P. mirabilis showed lowest susceptibility amongst all the test organisms (83.8%.Conclusion: Ceftriaxone can be used as a drug of choice in infections caused by S. aureus, E. coli, P. aurigenosa, K. pneumonia and S. typhi. However, it should be used with other antimicrobial agents in order to increase its effectiveness against P. mirabilis.

  20. Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus isolates from Trinidad & Tobago

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    Monteil Michele

    2006-07-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has become increasingly prevalent worldwide since it was first reported in a British hospital. The prevalence however, varies markedly in hospitals in the same country, and from one country to another. We therefore sought to document comprehensively the prevalence and antimicrobial susceptibility pattern of MRSA isolates in Trinidad and Tobago. Methods All Staphylococcus aureus isolates encountered in routine clinical specimens received at major hospitals in the country between 2000 and 2001 were identified morphologically and biochemically by standard laboratory procedures including latex agglutination test (Staphaurex Plus; Murex Diagnostics Ltd; Dartford, England; tube coagulase test with rabbit plasma (Becton, Dickinson & Co; Sparks, MD, USA, and DNase test using DNase agar (Oxoid Ltd; Basingstoke, Hampshire, England. MRSA screening was performed using Mueller-Hinton agar containing 6 μg oxacillin and 4% NaCl, latex agglutination test (Denka Seiken Co. Ltd, Tokyo, Japan and E-test system (AB Biodisk, Solna, Sweden. Susceptibility to antimicrobial agents was determined by the modified Kirby Bauer disc diffusion method while methicillin MICs were determined with E-test system. Results Of 1,912 S. aureus isolates received, 12.8% were methicillin (oxacillin resistant. Majority of the isolates were recovered from wound swabs (86.9% and the least in urine (0.4% specimens. Highest number of isolates was encountered in the surgical (62.3% and the least from obstetrics and gynaecology (1.6% facilities respectively. Large proportions of methicillin sensitive isolates are >85% sensitive to commonly used and available antimicrobials in the country. All MRSA isolates were resistant to ceftriaxone, erythromycin, gentamicin and penicillin but were 100% sensitive to vancomycin, rifampin and chloramphenicol. Conclusion There is a progressive increase in MRSA prevalence in the country but

  1. Combined antimicrobial susceptibility test against pan-drug-resistant Acinetobacter baumannii with E-test and microdilution checkerboard assay%应用E-test法、肉汤微量稀释棋盘法检测泛耐药鲍曼不动杆菌的试验

    Institute of Scientific and Technical Information of China (English)

    王铁山; 苏建荣

    2013-01-01

    Objective To evaluate the activity of antibiotics against pan-drug-resistant (PDR) Acinetobacter baumannii by combination antimicrobial susceptibility test in viro with epsilometric methods (Etest method) and microdilution checkerboard (CB method),and to detect a good correlation between timekill curve with the above mentioned two assays.Methods Thirty-one clinical isolates of PDR Acinetobacter baumannii were selected for mono and combination antimicrobial susceptibility test in vitro by E-test and CB method,then a comparison was conducted between the test results and the time-kill curve.Mono drugs involved tigecycline,colistin,imipenem and amikacin,and combinations involved two of drugs above,and three drugs involved imipenem/tigecycline,plus amikacin combination.Results Synergistic effect was detected in imipenem plus colistin and tigecycline plus imipenem combination.A high comparability was revealed between the E-test method with antimicrobial drugs added into the culture medium and the time-kill curves.Synergy in the combination of imipenem/tigecycline,plus amikacin was detected by the CB method and time-kill curves.Conclusion The results showed that the effect of specific combination of antibiotics against PDR Acinetobacter baumannii could be predicted by testing their synergistic effect with combination antimicrobial susceptibility test.%目的 比较E-test法和肉汤微量稀释棋盘法(CB法)检测体外联合药敏试验并与时间杀菌曲线对比的观察.方法 选择31株泛耐药(PDR)鲍曼不动杆菌临床株进行体外试验,分为替加环素、可立其丁、亚胺培南、阿米卡星单用和两药组合,亚胺培南+替加环素+阿米卡星三药组合也由CB法测试.这些测试的结果与时间杀菌曲线进行比较.结果 亚胺培南+可立其丁、替加环素+亚胺培南能检测到协同作用.培养基中加入抗菌药物的E-test法联合药敏试验与时间杀菌曲线更具有可比性.在三药组合中由CB法和

  2. The frequency of Neisseria gonorrhoeae endocervical infection among female carrier and changing trends of antimicrobial susceptibility patterns in Kashan, Iran.

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    Shima Afrasiabi

    2014-06-01

    Full Text Available Neisseria gonorrhoeae is the second most sexually transmitted diseases agents in developing countries. Antimicrobial resistance strains have created serious health concern. The aim of this study was to determine the frequency of endocervical gonococcal infection and antimicrobial susceptibility of N. gonorrhoeae in Kashan, Iran.In this study, 294 endocervical swabs were collected from married women referred to the obstetrics and gynecology clinics in Kashan from December 2012 to May 2013. The samples were cultured in modified Thayer Martin in 37°C with 5-10% CO2 for 72 hours. Gram staining, oxidase, catalase and carbohydrate utilization tests were used to identify the isolated species. All isolates were tested for their susceptibilities to antimicrobials using the Kirby Bauer-disk diffusion techniques.N. gonorrhoeae was detected in 2.38% of studied cases (95% confidence interval [CI] 1.5-3.26%. All isolates were resistance to ceftriaxone, penicillin G, ciprofloxacin, cefepime, and two isolate (28.5% showed intermediate sensitivity to tetracycline.Continued monitoring of prevalence of N. gonorrhoeae is important for preventing the dissemination of this microorganism. The present study emphasizes the importance of surveillance of antimicrobial resistance of N. gonorrhoeae in order to manage the rate of resistant strains and to revise the treatment policies.

  3. Antimicrobial Susceptibility and Genetic Characterisation of Burkholderia pseudomallei Isolated from Malaysian Patients

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    Yalda Khosravi

    2014-01-01

    Full Text Available Burkholderia pseudomallei, the causative agent of melioidosis, is intrinsically resistant to many antibiotics. Ceftazidime (CAZ, the synthetic β-lactam, is normally used as the first-line antibiotic therapy for treatment of melioidosis. However, acquired CAZ resistance can develop in vivo during treatment with CAZ, leading to mortality if therapy is not switched to a different antibiotic(s in a timely manner. In this study, susceptibilities of 81 B. pseudomallei isolates to nine different antimicrobial agents were determined using the disk diffusion method, broth microdilution test and Etest. Highest percentage of susceptibility was demonstrated to CAZ, amoxicillin/clavulanic acid, meropenem, imipenem, and trimethoprim/sulfamethoxazole. Although these drugs demonstrated the highest percentage of susceptibility in B. pseudomallei, the overall results underline the importance of the emergence of resistance in this organism. PCR results showed that, of the 81 B. pseudomallei, six multidrug resistant (MDR isolates carried bpeB, amrB, and BPSS1119 and penA genes. Genotyping of the isolates using random amplified polymorphic DNA analysis showed six different PCR fingerprinting patterns generated from the six MDR isolates clusters (A and eight PCR fingerprinting patterns generated for the remaining 75 non-MDR isolates clusters (B.

  4. Bacteremia among Jordanian children at Princess Rahmah Hospital: Pathogens and antimicrobial susceptibility patterns

    Directory of Open Access Journals (Sweden)

    A Mohammad

    2010-06-01

    Full Text Available Objective: To investigate microorganisms causing bacteremia in Jordanian children and to assess their sensitivity to various groups of antimicrobials."nMethods: A retrospective study was conducted on positive blood cultures taken from 378 children aged below 15 year, who sought medical attention at Princess Rahmah Hospital between January and December/2008."nResults: Out of 4475 tested blood samples, 378 isolates were recovered from blood cultures. The male to female isolate ratio was (1.26:1.0. The most frequent pathogen found was Staphylococcus aureus (86.2%, followed by Klebsiella spp. (9%, Escherichia coli (1.9%, Streptococcus spp. (1.9%, Pseudomonas spp. (0.8%, and Acinetobacter sp. was found in only one culture (0.3%. The susceptibility rate of S. aureus was recorded the highest (99.6% for vancomycin, and the lowest susceptibility rate (3.2% was recorded for aztreonam."nConclusions: Staphylococcus aureus was the main isolate in bacteremic children, with all isolates demonstrating susceptibility to vancomycin. Overall, aztreonam resistance was near 97%, and this rate was not affected by sex and blood isolate type. This information should be considered when empirical therapy is recommended or prescribed for children with bacteremia.

  5. Prevalence and antimicrobial susceptibility patterns of uropathogenic E. coli among people in Zakho, Iraq

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    Reem Fouad Polse

    2016-04-01

    Full Text Available Background: Antimicrobial resistance in uropathogenic E. coli is of major concern worldwide due to its increasing resistance to several commonly prescribed antibiotics. The aims of this study were to determine the prevalence and to evaluate the presence and antibiogram pattern of uropathogenic E. coli among people in Zakho city, Iraq. Methods: 1120 urine samples were collected from people. Samples were screened for E. coli isolates and their susceptibility to different antibiotics was analyzed. Results: Diagnoses tests showed that only 106 (9.4% isolates were E. coli. Females (90, 85% were more susceptible to urinary tract infections (UTIs than males (16, 15% (p <0.05. The age 11-21 years old (23, 21.7% was the most affected group (p <0.05. All isolates were resistant to penicillin, ampicillin and aztreonam. While, all these isolates were sensitive to imipenem and meropenem. Conclusions: The incidence of uropathogenic E. coli among people is comparable with reports from elsewhere. E. coli isolates are highly susceptible towards imipenem, and meropenem antibiotics, and highly resistant towards beta-lactam and cephalosporins antibiotics. Education programs and improving the hygienic measures are necessary to prevent contaminations with E. coli and minimize the use of beta-lactam and cephalosporin antibiotics. [Int J Res Med Sci 2016; 4(4.000: 1219-1223

  6. Comparison and Evaluation of Osiris and Sirscan 2000 Antimicrobial Susceptibility Systems in the Clinical Microbiology Laboratory

    OpenAIRE

    Nijs, A.; Cartuyvels, R.; Mewis, A; Peeters, V.; Rummens, J. L.; Magerman, K.

    2003-01-01

    The Osiris and Sirscan 2000 systems are two semiautomated systems that can be used to read and interpret the results on disk diffusion agar plates. They are both used for determination of susceptibility to antimicrobial agents. The present study compared both systems versus the NCCLS standard method of visual reading with a ruler. Both inpatient and outpatient samples with a total of 315 nonfastidious gram-negative strains were obtained. In total, 3,724 organism-antimicrobial agent combinatio...

  7. Antimicrobial susceptibility of ileal symbiont intracellularis isolated from pigs with proliferative enteropathy.

    OpenAIRE

    McOrist, S.; Mackie, R A; Lawson, G H

    1995-01-01

    Proliferative enteropathy is caused by the microaerophilic obligate intracellular bacterium ileal symbiont (IS) intracellularis. Treatment of this disease is problematic because of the lack of in vivo or in vitro data on the activities of antimicrobial agents. A new procedure for determining the susceptibility of IS intracellularis was developed by using a tissue culture system which promotes the in vitro multiplication of this organism. Nineteen antimicrobial agents were evaluated in triplic...

  8. Antimicrobial Susceptibility Pattern, Biochemical Characteristics and Biotyping of Salmonella paratyphi A: An Impact of Biofield Treatment

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Enteric fever is a major global problem. Emergence of antimicrobial resistance threatens to render current treatments ineffective. The current study was attempted to investigate the effect of biofield treatment on Salmonella paratyphi A (S. paratyphi A) in terms of antimicrobial susceptibility assay, biochemical characteristics and biotyping. S. paratyphi A strain were procured from MicroBioLogics in sealed packs bearing the American Type Culture Collection (ATCC 9150). The study was conducte...

  9. Antimicrobial Non-Susceptibility of Escherichia coli from Outpatients and Patients Visiting Emergency Rooms in Taiwan

    OpenAIRE

    Wang, Jann-Tay; Chang, Shan-Chwen; Chang, Feng-Yee; Fung, Chang-Phone; Chuang, Yin-Ching; Chen, Yao-Shen; Shiau, Yih-Ru; Tan, Mei-Chen; Wang, Hui-Ying; Lai, Jui-Fen; Huang, I-Wen; Yang Lauderdale, Tsai-Ling

    2015-01-01

    Longitudinal nationwide surveillance data on antimicrobial non-susceptibility and prevalence of extended-spectrum β-lactamases (ESBLs) as well as AmpC β-lactamases producers among Escherichia coli from different sources in the community settings are limited. Such data may impact treatment practice. The present study investigated E. coli from outpatients and patients visiting emergency rooms collected by the Taiwan Surveillance of Antimicrobial Resistance (TSAR) program. A total of 3481 E. col...

  10. In vitro susceptibility of Streptococcus mutans to chlorhexidine and six other antimicrobial agents.

    OpenAIRE

    Järvinen, H; Tenovuo, J; Huovinen, P

    1993-01-01

    The susceptibility of Streptococcus mutans to chlorhexidine and to six commonly used, systemic antibacterial agents (amoxicillin, cefuroxime, penicillin, sulfamethoxazole-trimethoprim, tetracycline, and erythromycin) was studied for 424 clinical isolates from 116 children and students. The MIC of chlorhexidine for all isolates was < or = 1 micrograms/ml. No resistance to the other antimicrobial agents was detected. Although widely exposed to various antimicrobial agents, S. mutans has remaine...

  11. Antimicrobial susceptibility of Clostridium difficile isolated from animals and humans in Brazil

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    Rodrigo Otávio Silveira Silva

    2014-05-01

    Full Text Available The objective of this study was to evaluate antimicrobial susceptibility in Clostridium difficile strains isolated from animals and humans in Brazil. The 54 C. difficile strains used were isolated from stool samples from piglets (n=16, dogs (n=13, humans (n=13, foals (n=8 calves (n=2, an ocelot (n=1 and a maned wolf (n=1. Antimicrobial susceptibility was determined using the serial plate agar dilution method for penicillin, florfenicol, oxytetracycline, erythromycin, vancomycin, metronidazole and tylosin. The C. difficile strains assessed were susceptible to metronidazole and vancomycin. Florfenicol resistance was rarely observed; 52 (96.4% strains were sensitive to this antimicrobial. Five (9.3%, five (9.3%, 14 (25.9% and 20 (37.0% strains were resistant to oxytetracycline, penicillin, tylosin and erythromycin respectively.

  12. Antimicrobial susceptibility and serovars of Salmonella from chickens and humans in Ibadan, Nigeria

    DEFF Research Database (Denmark)

    Fashae, K; Ogunsola, F; Aarestrup, Frank Møller;

    2010-01-01

    in 2007. All Salmonella isolates were serotyped and tested for antimicrobial susceptibility. RESULTS: Thirty-nine (4%) Salmonella isolates were obtained from human blood and 70 (11%) from chicken fecal samples. The human isolates revealed nine different serovars; 82% were non-typhoidal Salmonella and......BACKGROUND: This study determines the prevalence and antibiotic resistance of Salmonella serovars from humans and chickens in Ibadan, Nigeria, in 2004-2007. METHODOLOGY: A total of 991 blood samples were collected from patients in 2004 to 2005 and 641 fecal samples were collected from poultry farms....... Mouschaui, S. Jukestown, S. Oritamerin, and S. Onireke were isolated from both humans and chickens. Identical serovars were not found among human and chicken isolates. CONCLUSIONS: This study indicates that chickens are not a reservoir of Salmonella causing bacteraemia among humans in Ibadan, Nigeria...

  13. Antimicrobial susceptibility of environmental bovine mastitis pathogens in west central Iran.

    Science.gov (United States)

    Ebrahimi, Azizollah; Kheirabadi, K H Pirali; Nikookhah, Farzaneh

    2007-09-01

    The purpose of this study was to describe antimicrobial susceptibility of environmental mastitis pathogens isolated from dairy herds of Chahar Mahal province in west central Iran. Out of the 620 milk samples collected from the four districts, 180 were CMT (California mastitis test) positive that cultured and yield, 7 (3.88%) coagulase negative Staphylococci (CNS), 15 (8.33%) Streptococci other than agalactiae and 17 (9.44%) E. coli. CNS resistance to penicillin was 14.28% but for streptomycin, Oxytetracycline and Colistin, were 28.57%. Non agalactiae Streptococci resistance to Oxytetracycline and Kanamycin were 20 and 13.33%, respectively. E. coli resistance to penicillin, oxytetracycline, streptomycin, erythromycin and Colistin were 88.23, 82.35, 76.47, 76.47 and 52.94%, respectively. PMID:19090221

  14. Susceptibility to antimicrobial agents and plasmid carrying in Aeromonas hydrophila isolated from two estuarine systems.

    Science.gov (United States)

    Montoya, R; Dominguez, M; Gonzalez, C; Mondaca, M A; Zemelman, R

    1992-01-01

    Susceptibility to various antimicrobial agents and the presence of plasmids was investigated in eleven strains of Aeromonas hydrophila isolated from samples of sea water and these strains isolated from Aulacomya ater. Transference of resistance to Escherichia coli was attempted by conjugation and transformation experiments. The strains showed multiple resistance toward beta-lactam antibiotics and susceptibility to other antimicrobial agents. Five strains harboured plasmids with molecular weights below 5.7 MD. It was not possible to relate the resistance of the strains with the presence of their plasmids. PMID:1593967

  15. Antimicrobial Susceptibility and AP-PCR Typing of Acine¬tobac-ter Spp. Strains

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    R Ranjbar

    2007-10-01

    Full Text Available Background: Acinetobacter spp., as important opportunistic pathogens, have been found to be responsible for an increas­ing number of nosocomial infections. This study was undertaken to investigate the antimicrobial susceptibility and molecular typing of Iranian isolates of A. baumannii. Methods: The study was conducted over a period of 19 months in three hospitals in Tehran, Iran. Acinetobacter spp. were isolated from different clinical specimens using standard bacteriological methods. Antimicrobial susceptibility test was performed according to the standard CLSI guideline using 17 antibiotic disks. The AP-PCR fingerprinting was car­ried out using ARB11 primer. The PCR product was run and visualized in 2% agarose gels and stained with ethidium bro­mide. The AP-PCR profiles were grouped depending on the patterns of the amplified bands.Results: Sixty seven strains of Acinetobacter spp. (including 21 A. baumannii and 46 non- A. baumannii were isolated. The sources of these isolates were blood, urine, wound, and respiratory tract.  A. baumannii isolates were further studied. Re­sults showed that all A. baumannii isolates were resistant to at least 11 antibiotics tested. AP-PCR analysis of A. bauman­nii strains resulted in 7 different patterns. The dominant AP-PCR pattern was E (57.1%. Conclusion: Acinetobacter spp. are still important nosocomial pathogens in the region studied and most of isolates were multi-drug resistant. Our results also indicate that the AP-PCR technique represents a rapid and simple means for typing of A. baumannii.

  16. Elucidation of Antimicrobial Susceptibility Profiles and Genotyping of Salmonella enterica Isolates from Clinical Cases of Salmonellosis in New Mexico in 2008

    OpenAIRE

    Smith, Kenneth P.; George, Jeffy; Cadle, Kathleen M.; Kumar, Sanath; Aragon, Steven J.; Hernandez, Ricardo L.; Jones, Suzanna E.; Floyd, Jody L.; Varela, Manuel F.

    2010-01-01

    In this study, we investigated the antimicrobial susceptibility profiles and the distribution of some well known genetic determinants of virulence in clinical isolates of Salmonella enterica from New Mexico. The minimum inhibitory concentrations (MICs) for various antimicrobials were determined by using the E-test strip method according to CLSI guidelines. Virulence genotyping was performed by polymerase chain reaction (PCR) using primers specific for known virulence genes of Salmonella enter...

  17. Serotype Distribution, Antimicrobial Susceptibility, and Molecular Epidemiology of Streptococcus pneumoniae Isolated from Children in Shanghai, China.

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    Fen Pan

    Full Text Available Streptococcus pneumoniae is a common pathogenic cause of pediatric infections. This study investigated the serotype distribution, antimicrobial susceptibility, and molecular epidemiology of pneumococci before the introduction of conjugate vaccines in Shanghai, China.A total of 284 clinical pneumococcal isolates (270, 5, 4,3, and 2 of which were isolated from sputum, bronchoalveolar lavage fluid, blood, cerebral spinal fluid, and ear secretions, respectively from children less than 14 years of age who had not been vaccinated with a conjugate vaccine, were collected between January and December in 2013. All isolates were serotyped by multiplex polymerase chain reaction or quellung reactions and antimicrobial susceptibility testing was performed using the broth microdilution method. The molecular epidemiology of S.pneumoniae was analyzed by multilocus sequence typing (MLST.Among the 284 pneumococcal isolates, 19F (33.5%, 19A (14.1%, 23F (12.0%, and 6A (8.8% were the most common serotypes and the coverage rates of the 7-, 10-, and 13-valent pneumococcal conjugate vaccines (PCV7, PCV10, and PCV13 were 58.6%, 59.4% and 85.1%, respectively. Antimicrobial susceptibility showed that the prevalence rates of S.pneumoniae resistance to penicillin were 11.3% (32/284. Approximately 88.0% (250/284 of the isolates exhibited multi-drug resistance. MLST analysis revealed a high level of diversity, with 65 sequence types (STs among 267 isolates. Specifically, the four predominant STs were ST271 (24.3%, 65/267, ST320 (11.2%, 30/267, ST81 (9.7%, 26/267, and ST3173 (5.2%, 14/267, which were mainly associated with serotypes 19F, 19A, 23F, and 6A, respectively.The prevalent serotypes among clinical isolates from children were 19F, 19A, 23F, and 6A and these isolates showed high resistance rates to β-lactams and macrolides. The Taiwan19F-14 clone played a predominant role in the dissemination of pneumococcal isolates in Shanghai, China. Therefore, continued and

  18. Antimicrobial susceptibility of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Enterobacteriaceae isolates to fosfomycin

    OpenAIRE

    Falagas, Matthew E.; Maraki, Sofia; Karageorgopoulos, Drosos E.; Kastoris, Antonia C.; Mavromanolakis, Emmanuel; Samonis, George

    2010-01-01

    Abstract The advancing antimicrobial drug resistance among Enterobacteriaceae renders the evaluation of potential novel therapeutic options necessary. We sought to evaluate the in vitro antimicrobial activity of fosfomycin against multidrug-resistant (MDR) Enterobacteriaceae isolates. Antimicrobial susceptibility to fosfomycin and 12 additional antibiotics of MDR Enterobacteriaceae isolates collected between November 2007 and April 2009 at the University Hospital of Heraklion, Cret...

  19. Antimicrobial susceptibility survey of pathogens isolated from selected patients in Northern Italy

    Directory of Open Access Journals (Sweden)

    Elisabetta Maioli

    2005-03-01

    Full Text Available The Clinical Microbiology Laboratory of the University of Genoa participated, during the year 2003, in an international antimicrobial surveillance program.The collection of isolates was done according to the site of infection and/or type of patient. Four hundred twenty (420 clinical isolates were analyzed during this year and the frequencies of the different pathogens were investigated. A reference centre carried out susceptibility tests. Oxacillin-resistant Staphylococcus aureus represented 47.6% of all S. aureus isolates from blood stream infections and 33.3% of all S. aureus isolated from skin and soft tissue infections in hospitalised patients.These strains showed resistance to most of the antimicrobial agents evaluated, except vancomycin, teicoplanin, quinupristin/dalfopristin and linezolid which registered 100% of susceptibility. Some isolates from blood stream infections such as E. coli demonstrated resistance to ciprofloxacin (23.3%, levofloxacin (20%, and gatifloxacin (16.6%, and Klebsiella pneumoniae was resistant (18% to all fluoroquinolones tested. Pseudomonas aeruginosa manifested resistance to ciprofloxacin (16.6%, while 27.7% of these strains were resistant both to levofloxacin and gatifloxacin. All the Enterobacter cloacae isolated from blood were susceptible to ciprofloxacin, levofloxacin and gatifloxacin. Haemophilus influenzae and Moraxella catarrhalis collected from community-acquired respiratory tract infections were all inhibited by ciprofloxacin, levofloxacin and gatifloxacin. E. coli isolated from urinary tract infections in hospitalised patients were resistant to ciprofloxacin, levofloxacin and gatifloxacin (2.7%. All Salmonella spp. collected from samples of patients affected by infections of the gastro-intestinal tract were susceptible to all fluoroquinolones. Penicillin resistance in Streptococcus pneumoniae was found in 21.4% of isolates from patients with respiratory tract infections. Fluoroquinolone resistance was

  20. Antimicrobial Susceptibility of Staphylococci Isolated from Clinical Mastitis in Dairy Cows in Two Regions of Kosovo

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    DRITON SYLEJMANI

    2015-12-01

    Full Text Available This study was undertaken to evaluate antibiotic susceptibility of 26 strains of Coagulase Negative Staphylococci (CNS and 18 strains of Staphylococcus aureus isolated from samples of dairy cows with clinical mastitis. The isolates species of staphylococci were identified by using coagulase test (using rabbit plasma and API Staph system (bioMėrieux SA which differentiates S. aurues from other staphylococci. Isolates were tested for antimicrobial susceptibility on Mueller Hinton agar by dick diffusion method according to the Clinical Laboratory Standards Institute (CLSI/NCCLS. The findings of this study showed that the most effective in vitro drugs for S. aureus strains isolated from cows with clinical mastitis were amoxycillin/clavulanic acid (83.3%, tetracycline (77.8%, gentamycin (77.8% and trimethoprim (66.7% and for CNS strains trimethoprim (88.5%, amoxicillin-clavulanic acid (84.6%, tetracycline (77% and gentamicin (69.2% while the isolates of S. aureus and CNS were found to be more resistant to penicillin (55.5% and 53.8%, respectively, streptomycin (50% and 46.1%, respectively and ampicillin (38.9% and 46.1%, respectively.

  1. Variation in Streptococcus pneumoniae susceptibility to human antimicrobial peptides may mediate intraspecific competition

    OpenAIRE

    Habets, Michelle G. J. L.; Rozen, Daniel E; Brockhurst, Michael A

    2012-01-01

    Streptococcus pneumoniae is a facultative pathogen inhabiting the nasopharynx of humans where it is exposed to a range of antimicrobial peptides (AMPs) of the innate immune response. It is possible therefore that the susceptibility of strains to AMPs plays a role in determining their ability to colonize, and furthermore, that AMPs could mediate competitive interactions between co-colonizing genotypes. However, little is known about patterns of natural variation in AMP susceptibility of S. pne...

  2. Susceptibility of common bacterial respiratory pathogens to antimicrobial agents in outpatients from south Backa District

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    Horvat Olga

    2014-01-01

    Full Text Available Introduction. Acute infections of the upper respiratory tract are the most common reasons why patients visit general practitioners. Overuse of antibiotics in treatment of these conditions is extremely common practice although these infections are most frequently caused by viruses. The aim of this study was to determine the distribution and susceptibility of common pathogens to antimicrobial agents that cause infections of the upper respiratory tract in outpatients and to determine whether the results obtained from the examined sample were in accordance with the recommendations of the current National Guideline. Material and Methods. .The study included 945 strains isolated from the throat and nasal swabs from January 1st to March 31st, 2008, as well as from 330 strains isolated from January 1st to March 31st, 2013 in South Backa District, Serbia. Susceptibility tests were performed by the standard disc diffusion method and according to the criteria recommended by the Clinical and Laboratory Standards Institute. Results. The most commonly isolated strains were Streptococcus pyogenes, Staphylococcus aureus, Streptococcus pneumoniae, Branchamella catarrhalis, and Haemophilus influenzae. Susceptibility of Streptococcus pyogenes, Branchamella catarrhalis and Haemophilus influenzae to examined antibiotics did not substantially change over the two study periods. None of the isolates of Staphylococcus aures demonstrated resistance to methicillin in 2008, while the percentage of resistant strains was 5.93% in 2013. Susceptibility rates of Staphylococcus pneumoniae isolates to erythromycin and clindamycin were lower in 2013 than in 2008. Conclusion. The investigation results follow the recommendations of the National Guideline for the usage of natural penicillin in the treatment of tonsillopharyngitis. Amoxicillin/clavulanic acid is recommended for the treatment of rhinosinusitis, and second generation cephalosporins are the second choice.

  3. The identification, typing, and antimicrobial susceptibility of Pseudomonas aeruginosa isolated from mink with hemorrhagic pneumonia.

    Science.gov (United States)

    Qi, Jing; Li, Lulu; Du, Yijun; Wang, Shourong; Wang, Jinwen; Luo, Yanbo; Che, Jie; Lu, Jinxing; Liu, Hui; Hu, Guangchun; Li, Jixia; Gong, Yanwen; Wang, Guisheng; Hu, Ming; Shiganyan; Liu, Yuqing

    2014-06-01

    The biological characteristics and molecular epidemiology of Pseudomonas aeruginosa associated with mink hemorrhagic pneumonia from Shandong province of eastern China were determined in this study. From 2010 to 2011, 30 mink P. aeruginosa isolates were identified from lung, fecal and feed samples of clinical cases and subjected to serotyping, antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) using SpeI. The P. aeruginosa isolates belonged to four serotypes-21 of type G, four of type I, three of type M, one of type B, and one non-typable strain. The strains were divided into four large groups as determined by PFGE. Isolates from the group 2 were highly homologous and were obtained from the same region as an epidemic. All of the isolates were sensitive to piperacillin, piperacillin/tazobactam, ceftazidime, cefepime, imipenem, amikacin, gentamicin and tobramycin and resistant to ampicillin, cefuroxime and cefuroxime axetil. A high frequency of resistance was found to ampicillin/sulbactam, cefazolin, cefotetan, ceftriaxone, nitrofurantoin, and trimethoprim/sulfamethoxazole (96.7%). Resistance to ticarcillin/clavulanic acid, ciprofloxacin and levofloxacin was less common (13.3%). There was no relationship between antibiotic resistance and serotype distribution of the isolates. The epidemic serotype of P. aeruginosa from the mink hemorrhagic pneumonia in Shandong province was type G, which was a clone of commonly found in this province. These findings reveal the genetic similarities and antimicrobial susceptibility profiles of P. aeruginosa from clinical cases of mink hemorrhagic pneumonia and will facilitate the prevention and control of the disease in Shandong province of China. PMID:24629901

  4. Antimicrobial susceptibility profile of uropathogens in Maluti Adventist Hospital patients, 2011

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    Phillip Mubanga

    2015-02-01

    Full Text Available Background: Urinary tract infections (UTIs are amongst the most common infections encountered globally and are usually treated empirically based on bacterial resistance to antibiotics for a given region. Unfortunately in Lesotho, no published studies are available to guide doctors in the treatment of UTIs. Treatment protocols for Western countries have been adopted, which may not be applicable for this region.Aim: To determine the antimicrobial susceptibility profile of uropathogens in outpatients at the Maluti Adventist Hospital.Setting: The study was conducted at the outpatient department of the Maluti Adventist Hospital in Mapoteng, Lesotho.Methods: This was a prospective cross-sectional study using consecutive sampling of patients with clinical symptoms of UTI. Midstream urine samples were screened through chemistry and microscopy, then positive urine samples were cultured. The isolated uropathogens underwent antimicrobial susceptibility testing and inclusion continued until 200 culture samples were obtained. Descriptive statistics were used in the data analysis.Results: The top five cultured uropathogens were Escherichia coli (61.5%, Staphylococcus aureus (14%, Pseudomonasspecies (6.5%, Enterococcus faecalis (5.5% and Streptococcus agalactiae (5%. The isolated uropathogens showed low sensitivity to cotrimoxazole (32.5% – 75.0% and amoxicillin (33.2% – 87.5% and high sensitivity to ciprofloxacin (84.0% – 95.1% and nitrofurantoin (76.9% – 100%.Conclusion: In the Maluti setting, cotrimoxazole and amoxicillin should be avoided as first-line drugs for the empirical treatment of community-acquired UTI. We recommend the use of nitrofurantoin as first choice.

  5. Antimicrobial susceptibilities of clinical isolates of Acinetobacter baumannii from Singapore.

    OpenAIRE

    Kuah, B G; Kumarasinghe, G; Doran, J.; Chang, H R

    1994-01-01

    The in vitro activities of 17 antimicrobial agents alone or in combination against 70 clinical isolates of Acinetobacter baumannii from Singapore were determined by broth microdilution. The MICs of amoxicillin, ampicillin, ceftazidime, ceftriaxone, gentamicin, and piperacillin for 90% of the strains were > or = 128 micrograms/ml. Addition of sulbactam to ampicillin produced improved activity, whereas adding tazobactam to piperacillin did not. The MICs of amikacin, ciprofloxacin, and imipenem ...

  6. Antimicrobial Susceptibility Pattern and Biochemical Characteristics of Staphylococcus aureus: Impact of Bio field Treatment

    OpenAIRE

    Mahendra Kumar Trivedi

    2015-01-01

    Study background: Staphylococci are widespread in nature, mainly found on the skin and mucous membranes. Staphylococcus aureus (S. aureus) is the key organism for food poisoning due to massive production of heat stable exotoxins. The current study was attempted to investigate the effect of biofield treatment on antimicrobial susceptibility pattern and biochemical characteristics of S. aureus (ATCC 25923).

  7. Serogroups and antimicrobial susceptibility among Escherichia coli isolated from farmed mink (Mustela vison Schreiber) in Denmark

    DEFF Research Database (Denmark)

    Vulfson, L.; Pedersen, Karl; Chriel, M.; Frydendahl, K.; Andersen, T.H.; Madsen, Mogens; Dietz, H.H.

    2001-01-01

    Escherichia coli is commonly found in outbreaks of diarrhoea in mink during the production season although its role as a primary causal organism remains unclear. The present study was undertaken to determine the serogroups and antimicrobial susceptibility of E. coli isolates from healthy and diar...

  8. Antibiotic susceptibility and antimicrobial activity of autochthonous starter cultures as safety parameters for fresh cheese production

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    Dora Bučan

    2013-11-01

    Full Text Available The antibiotic susceptibility and antimicrobial activity, as food safety parameters important for application of autochthonous lactic acid bacteria (LAB, that previously satisfied technological criteria for functional starter cultures in fresh cheese production were examined. Soluble whole cell protein patterns of autochthonous LAB strains from fresh cheese, obtained by SDS-PAGE, revealed the presence of two predominant strains, which were identified as Lactobacillus fermentum A8 and Enterococcus faecium A7. These strains were not resistant and shown susceptibility to antibiotics: ampicillin, bacitracin, penicillin G, azithromycin, chloramphenicol, clarithromycin, clindamycin, spiramycin, tetracycline, streptomycin, neomycin, gentamicin, erythromycin, rifampicin and novobiocin. Lb. fermentum A8 strain displayed phenotypic resistance to vancomycin, but this resistance is intrinsic, not transferable and it is acceptable from the safety aspect. The capacity of Lb. fermentum A8 and Ec. faecium A7 to inhibit growth of test-microorganisms Listeria monocytogenes ATCC 11911, Escherichia coli 3014, Salmonella enterica serovar Typhimurium FP1 and Staphylococcus aureus 3048, was also analysed. According to obtained results, Lb. fermentum A8 and Ec. faecium A7 are safe from the aspect of spreading antibiotic resistance and could be useful as bioprotective cultures that inhibit common bacterial food contaminants, including L. monocytogenes.

  9. Antimicrobial susceptibility pattern of acinetobacter species-one year experience in a tertiary care setting

    International Nuclear Information System (INIS)

    Objective: To find out antimicrobial susceptibility pattern of Acinetobacter species isolated from 1 January 2009 through 31 December 2009 at Department of Microbiology, Armed Forces Institute of Pathology Rawalpindi. Materials and Methods: A total of 276 isolates of Acinetobacter spp yielded from various clinical specimens during the study period were included Routine conventional methods were used to identify various species of Acinetobacter and modified Kirby-Bauer disk diffusion method was used for susceptibility testing. Out of total 276 isolates, 176 (63.8%) turned out to be Acinetobacter baumannii and 100 (36.2%) were Acinetobacter johnsonii. Overall sensitivity of Acinetobacter spp against piperacillin/sulbactam, tigecycline, sulbactam/cefoperazone, piperacillin/tazobactam, imipenem, doxycycline, ceftazidime, ciprofloxacin, chloramphenicol, trimethoprim /sulfamethoxazole, ampicillin, gentamycin, ceftriaxone, amoxicillin/clavulanic acid and ampicillin were 64%,63%, 48%, 47%, 41%,39%,35%, 34%, 32%, 31 %, 29%, 19%, 18% and 5% respectively. Out of 276 isolates, 181 (66 %) were multidrug resistant while 33 (18 %) isolates were pan-drug resistant. (author)

  10. Standardization of a broth microdilution susceptibility testing method to determine minimum inhibitory concentrations of aquatic bacteria

    DEFF Research Database (Denmark)

    Miller, R.A.; Walker, R.D.; Carson, J.;

    2005-01-01

    -Hinton broth. These QC ranges were accepted by the CLSI/NCCLS Subcommittee on Veterinary Antimicrobial Susceptibility Testing in January 2004. This broth microdilution testing method represents the first standardized method for determining MICs of bacterial isolates whose preferred growth temperatures......A multiple laboratory study was conducted in accordance with the standards established by the Clinical and Laboratory Standards Institute (CLSI), formerly the National Committee for Clinical Laboratory Standards (NCCLS), for the development of quality control (QC) ranges using dilution...... antimicrobial susceptibility testing methods for bacterial isolates from aquatic animal species. QC ranges were established for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 when testing at 22, 28 and 35 degrees C (E. coli only) for 10 different antimicrobial agents...

  11. Antimicrobial susceptibility of listeria monocytogenes from food products

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Knöchel, Susanne; Hasman, Henrik

    2007-01-01

    susceptibility to ceftiofur, chloramphenicol, ciprofloxacin, erythromycin, florfenicol, penicillin, spectinomycin, streptomycin, tetracycline, tiamulin, trimethoprim, and co-trimoxazole, and the disinfectants benzalkonium chloride and triclosan, by determination of minimum inhibitory concentrations (MICs). All...... isolates were resistant to ceftiofur, but susceptible to the other antibiotics. A single isolate had a MIC of 4 mg/L for ciprofloxacin. For tiamulin. the MIC values were around the breakpoint used. Most isolates had MICs for triclosan at 16 mg/L. The MICs for benzalkonium chloride formed a bimodal...

  12. Antimicrobial susceptibilities of clinical isolates of Acinetobacter baumannii from Singapore.

    Science.gov (United States)

    Kuah, B G; Kumarasinghe, G; Doran, J; Chang, H R

    1994-10-01

    The in vitro activities of 17 antimicrobial agents alone or in combination against 70 clinical isolates of Acinetobacter baumannii from Singapore were determined by broth microdilution. The MICs of amoxicillin, ampicillin, ceftazidime, ceftriaxone, gentamicin, and piperacillin for 90% of the strains were > or = 128 micrograms/ml. Addition of sulbactam to ampicillin produced improved activity, whereas adding tazobactam to piperacillin did not. The MICs of amikacin, ciprofloxacin, and imipenem for 90% of the strains were 32, 32, and 16 micrograms/ml, respectively. PMID:7840598

  13. A 5 year (2005-2009 review of antimicrobial susceptibility of clinical Klebsiella pneumoniae isolates from pediatric patients in Jordan

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    Mohammad Al-Shara

    2013-10-01

    Full Text Available Aim of the Study: The present study was conducted to investigate antimicrobial susceptibility pattern of Klebsiella pneumoniae strains isolated from clinical specimens of Jordanian pediatric patients during a five year period from 2005-2009. A total of 1023 Klebsiella pneumoniae strains were isolated from clinical specimens and tested for their susceptibility to different antimicrobial drugs. Main findings: Overall, high susceptibility rate was recorded for ciprofloxacin (90.5%, followed by norfloxacin (84.8%, imipenem (69.9%, nalidixic acid (66.6%, and cefixime (63.9%. Low susceptibility rate was recorded for ampicillin (16.6%, followed by amoxicillin-clavulanic acid (22.5%, tobramycin (28.6%, amikacin (31.4%, cotrimoxazole (37.3%, and aztreonam (39.3%, Conclusion: most of β-lactam antibiotics as well as tobramycin, amikacin, cotrimoxazole, and aztreonam, should not be used in treating infections caused by pathogenic K. pneumoniae and other related bacteria in Jordan. However, quinolone compounds and imipenem seem to be effective in treatment of infections caused by pathogenic K. pneumoniae in children.

  14. Solobacterium moorei Bacteremia: Identification, Antimicrobial Susceptibility, and Clinical Characteristics▿

    OpenAIRE

    Pedersen, Rune Micha; Holt, Hanne Marie; Justesen, Ulrik Stenz

    2011-01-01

    We present five cases of Solobacterium moorei bacteremia. The isolates were identified with 16S rRNA gene sequencing and were susceptible to common antibiotics used for anaerobic infections. Bacteremia with S. moorei seems to be associated with debilitating conditions, but the prognosis of the infection appears to be good.

  15. Solobacterium moorei bacteremia: identification, antimicrobial susceptibility, and clinical characteristics

    DEFF Research Database (Denmark)

    Micha Pedersen, Rune; Holt, Hanne Marie; Justesen, Ulrik Stenz

    2011-01-01

    We present five cases of Solobacterium moorei bacteremia. The isolates were identified with 16S rRNA gene sequencing and were susceptible to common antibiotics used for anaerobic infections. Bacteremia with S. moorei seems to be associated with debilitating conditions, but the prognosis of the in...

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

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    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.

  17. Antimicrobial susceptibility of Gram-negative bacteria causing intra-abdominal infections in China: SMART China 2011

    Institute of Scientific and Technical Information of China (English)

    Zhang Hui; Yang Qiwen; Xiao Meng; Chen Minjun; Robert E.Badal; Xu Yingchun

    2014-01-01

    Background The Study for Monitoring Antimicrobial Resistance Trends program monitors the activity of antibiotics against aerobic and facultative Gram-negative bacilli (GNBs) from intra-abdominal infections (IAIs) in patients worldwide.Methods In 2011,1 929 aerobic and facultative GNBs from 21 hospitals in 16 cities in China were collected.All isolates were tested using a panel of 12 antimicrobial agents,and susceptibility was determined following the Clinical Laboratory Standards Institute guidelines.Results Among the Gram-negative pathogens causing IAIs,Escherichia coli (47.3%) was the most commonly isolated,followed by Klebsiella pneumoniae (17.2%),Pseudomonas aeruginosa (10.1%),and Acinetobacter baumannii (8.3%).Enterobacteriaceae comprised 78.8% (1521/1929) of the total isolates.Among the antimicrobial agents tested,ertapenem and imipenem were the most active agents against Enterobacteriaceae,with susceptibility rates of 95.1% and 94.4%,followed by amikacin (93.9%) and piperacillin/tazobactam (87.7%).Susceptibility rates of ceftriaxone,cefotaxime,ceftazidime,and cefepime against Enterobacteriaceae were 38.3%,38.3%,61.1%,and 50.8%,respectively.The leastactive agent against Enterobacteriaceae was ampicillin/sulbactam (25.9%).The extended-spectrum β-lactamase (ESBL) rates among E.coli,K.pneumoniae,Klebsiella oxytoca,and Proteus mirabilis were 68.8%,38.1%,41.2%,and 57.7%,respectively.Conclusions Enterobacteriaceae were the major pathogens causing IAIs,and the most active agents against the study isolates (including those producing ESBLs) were ertapenem,imipenem,and amikacin.Including the carbapenems,most agents exhibited reduced susceptibility against ESBL-positive and multidrug-resistant isolates.

  18. Pathogenic bacteria profile and antimicrobial susceptibility patterns of ear infection at Bahir Dar Regional Health Research Laboratory Center, Ethiopia.

    Science.gov (United States)

    Hailu, Derese; Mekonnen, Daniel; Derbie, Awoke; Mulu, Wondemagegn; Abera, Bayeh

    2016-01-01

    Ear infection linked with frequent antibiotic prescription, hearing impairment, severe disability and death is a public health threat in developing countries. However, there is scarcity of documented data in the study area. Therefore, this study aimed at determining bacterial etiologic agents and their antimicrobial susceptibility patterns among patients of all age groups referred to Bahir Dar Regional Health Research Laboratory Center. Retrospective data recorded on culture and antimicrobial susceptibility profile were retrieved for analysis. Pus swabs from discharging ears collected and processed for aerobic bacteria culture and susceptibility testing. Of the total 368 pus swab samples processed, 296 (80.4 %) were culture positive. Of which, 289 (97.6 %) were bacteria and 7 (2.4 %) were yeast cells. The proportion of ear infection was higher in males (92.7 %) than females (65 %) (P = 0.014). The frequency of ear infection below 21 years of age was 65.2 %. The predominant isolate was Pseudomonas aeruginosa (29.7 %) followed by Staphylococcus aureus (26.3 %) and Proteus spp. (21.9 %). High level of antimicrobial resistance rates were observed for amoxicillin/clavulanic acid, ampicillin and penicillin whereas ciprofloxacin, ceftriaxone, chloramphenicol, cotrimoxazole, gentamicin and amikacin were found effective against the isolated bacteria. Aerobic bacterial otitis media linked with high levels of resistance against amoxicillin/clavulanic acid and ampicillin is major health problem in the study area. Moreover, considerable level of oxacillin resistant S. aureus suggests the diffusion of methicillin resistant S. aureus in the community. Therefore, treatment of otitis media in the study area needs to be guided by antibiotic susceptibility testing of isolates. PMID:27119070

  19. Antimicrobial susceptibility and genetic characteristics of Neisseria gonorrhoeae isolates from India, Pakistan and Bhutan in 2007–2011

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    Sethi Sunil

    2013-01-01

    Full Text Available Abstract Background Knowledge on antimicrobial drug resistance and genetic characteristics of Neisseria gonorrhoeae isolates circulating in India, Pakistan, and Bhutan is sorely lacking. In this paper, we describe the prevalence of antimicrobial resistance and molecular characteristics of N. gonorrhoeae isolates from India, Pakistan, and Bhutan in 2007–2011. Methods Antimicrobial susceptibility and β-lactamase production were tested for 65 N. gonorrhoeae isolates from India (n=40, Pakistan (n=18 and Bhutan (n=7 using Etest methodology (eight antimicrobials and nitrocefin solution, respectively. Resistance determinants, i.e. penA, mtrR, porB1b, gyrA, and parC, were sequenced. N. gonorrhoeae multiantigen sequence typing (NG-MAST was performed for molecular epidemiology. Results The highest resistance level was observed for ciprofloxacin (94%, followed by penicillin G (68%, erythromycin (62%, tetracycline (55%, and azithromycin (7.7%. All the isolates were susceptible to ceftriaxone, cefixime, and spectinomycin. Thirty-four (52% of the isolates were producing β-lactamase. No penA mosaic alleles or A501-altered alleles of penicillin-binding protein 2 were identified. Forty-nine NG-MAST STs were identified, of which 42 STs have not been previously described worldwide. Conclusions Based on this study, ceftriaxone, cefixime, and spectinomycin can be used as an empirical first-line therapy for gonorrhoea in India, Pakistan, and Bhutan, whereas ciprofloxacin, penicillin G, tetracycline, erythromycin, and azithromycin should not be. It is imperative to strengthen the laboratory infrastructure in this region, as well as to expand the phenotypic and genetic surveillance of antimicrobial resistance, emergence of new resistance, particularly, to extended-spectrum cephalosporins, and molecular epidemiology.

  20. Data Mining Validation of Fluconazole Breakpoints Established by the European Committee on Antimicrobial Susceptibility Testing▿

    Science.gov (United States)

    Cuesta, Isabel; Bielza, Concha; Larrañaga, Pedro; Cuenca-Estrella, Manuel; Laguna, Fernando; Rodriguez-Pardo, Dolors; Almirante, Benito; Pahissa, Albert; Rodríguez-Tudela, Juan L.

    2009-01-01

    European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints classify Candida strains with a fluconazole MIC ≤ 2 mg/liter as susceptible, those with a fluconazole MIC of 4 mg/liter as representing intermediate susceptibility, and those with a fluconazole MIC > 4 mg/liter as resistant. Machine learning models are supported by complex statistical analyses assessing whether the results have statistical relevance. The aim of this work was to use supervised classification algorithms to analyze the clinical data used to produce EUCAST fluconazole breakpoints. Five supervised classifiers (J48, Correlation and Regression Trees [CART], OneR, Naïve Bayes, and Simple Logistic) were used to analyze two cohorts of patients with oropharyngeal candidosis and candidemia. The target variable was the outcome of the infections, and the predictor variables consisted of values for the MIC or the proportion between the dose administered and the MIC of the isolate (dose/MIC). Statistical power was assessed by determining values for sensitivity and specificity, the false-positive rate, the area under the receiver operating characteristic (ROC) curve, and the Matthews correlation coefficient (MCC). CART obtained the best statistical power for a MIC > 4 mg/liter for detecting failures (sensitivity, 87%; false-positive rate, 8%; area under the ROC curve, 0.89; MCC index, 0.80). For dose/MIC determinations, the target was >75, with a sensitivity of 91%, a false-positive rate of 10%, an area under the ROC curve of 0.90, and an MCC index of 0.80. Other classifiers gave similar breakpoints with lower statistical power. EUCAST fluconazole breakpoints have been validated by means of machine learning methods. These computer tools must be incorporated in the process for developing breakpoints to avoid researcher bias, thus enhancing the statistical power of the model. PMID:19433568

  1. STAPHYLOCOCCUS AUREUS NASAL CARRIAGE AMONG INJECTING AND NON-INJECTING DRUG USERS AND ANTIMICROBIAL SUSCEPTIBILITY

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    Mojtaba Varshochi

    2013-01-01

    Full Text Available Staphylococcus Aureus (SA is one of the most prevalent bacterial pathogens in human beings. Approximately 20% of healthy persons are persistent carriers and 60% are intermittent carriers of SA. Nasal cavity is one of the most important sites of its colonization. Intravenous (IV drug abuse has been proposed as a risk factor for colonization of SA in the nasal mucosa. The goal of this study was to determine the frequency of SA carriers in nasal cavity among IV and non-IV drug abusers (addicts, as well as to assess the antimicrobial susceptibility pattern of the positive cases. In a cross-sectional analysis of 300 drug addicts (Group I: 100 non-injecting addicts, Group II: 100 IV injecting drug addicts in rehab, Group III: 100 IV injecting drug addicts not in rehab in the infectious diseases clinics of Tabriz’s Imam Reza and Sina teaching hospitals and the rehabilitation center of Razi hospital, were investigated. Hospitalized addicts, insulin-dependent diabetic cases, HIV positive patients and those on chronic hemodialysis were excluded. The nasal mucosal sample was prepared from each case for SA isolation and its antimicrobial susceptibility was investigated by antibiogram. Eighty-four cases (28% were culture positive for SA, including 26 cases in group one, 32 cases in group two and 26 cases in group three (p = 0.55. There was only one MRSA isolate present in all the cases studied (1.2%. No resistance to linozolid, rifampin and vancomycin was observed. The resistance to erythromycin, cefoxitin, ciprofloxacin, clindamycin, co-trimoxazol and gentamicin were 3.6, 4.8, 2.4, 3.6, 1.2 and 2.4% respectively. No statistically significant differences existed between the three groups in antibacterial susceptibility pattern. Sensitivity to oxacillin using the E-test results and disc diffusion were completely consistent. The percentage of carries of SA in the anterior nasal mucosa among IV and non-IV drug addicts is not considerably higher than the

  2. 65株不同圈养野生动物源性肠杆科菌的药敏分析%Application of the Antimicrobial Susceptibility Test for Enterobacteriaceae in 65 Species of Captive Wild Animals

    Institute of Scientific and Technical Information of China (English)

    黄淑芳; 胡新波; 王才益; 江志

    2011-01-01

    Using the method of K-B antimicrobial susceptibility test(AST),we analyzed the drug susceptibility of intestinal rod bacteria to 10 kinds of clinical antibiotics including penicillins,cephalosporins,dilute aminoglycoside,quinolones,and sulfonamides.Intestinal rod bacteria were sampled from wild animals held at Hangzhou Zoo.The most effective drugs were the third generation cephalosporin,cefoperazone,and cefotaxime,which eliminated 83.1%of bacteria.Less effective antibiotics included quinolone and aminoglycoside drugs,which eliminated 60%or more of bacteria.Least effective was cefradine,a first generation cephalosporin.Effectiveness of cephradine was 58.5%,while that of ampicillin penicillin was 43.1%,and that of sulfamethoxazole of quinolone sulfa was 21.5%.This research provides a basis for clinical medication of captive wildlife.%采用K-B法药敏试验,分析圈养野生动物肠杆科菌对青霉素类、头孢类、氨基糖甙类、喹诺酮类、磺胺类的10种临床常用抗生素的药敏情况。结果显示:最敏感的是头孢稀类的三代头孢,头孢哌酮和头孢噻肟,其敏感率均为83.1%;较敏感的为喹诺酮类和氨基糖甙类药物,敏感率大于或等于60%;敏感性较差的是一代头孢中的头孢拉定、磺胺类药中的复方新诺明、青霉素类的氨苄青霉素,其敏感性分别为58.5%、43.1%和21.5%,被研究结果为兽医临床用药提供了依据。

  3. Antimicrobial susceptibility of Mycoplasma bovis isolates from veal calves and dairy cattle in the Netherlands.

    Science.gov (United States)

    Heuvelink, Annet; Reugebrink, Constance; Mars, Jet

    2016-06-30

    Control of Mycoplasma bovis infections depends on good husbandry practices and antibiotic treatment. To allow more prudent use of antimicrobial drugs, there is a need for information on the susceptibility profile of this pathogen. The objective of the present study was to analyse the in vitro antimicrobial susceptibility of clinical M. bovis isolates in the Netherlands. The collection comprised 95 bovine isolates, originating from lungs (n=56), mastitis milk (n=27), and synovial fluid (n=12), collected between 2008 and 2014. Minimal inhibitory concentrations (MICs) were assessed by broth microdilution, both by using in-house prepared MIC plates and by using commercially available MIC plates. For each antimicrobial agent, the range of MIC results, the MIC50, and MIC90 values were calculated. M. bovis strains recently isolated in the Netherlands appeared to be characterized by relatively high MIC values for antimicrobial agents that, until now, have been recommended by the Dutch Association of Veterinarians for treating pneumonia caused by Mycoplasma species. Fluoroquinolones appeared to be the most efficacious in inhibiting M. bovis growth, followed by tulathromycin and oxytetracycline. The highest MIC values were obtained for erythromycin, tilmicosin, and tylosin. Future studies should be done on determining M. bovis specific clinical breakpoints, standardization of methods to determine MIC values as well as molecular studies on detection of antimicrobial resistance mechanisms of M. bovis isolates to develop PCR assays for determining resistance. PMID:27259820

  4. Antimicrobial susceptibility of Clostridium perfringens isolated from domestic and wild animal species in Brazil

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    Carlos Augusto de Oliveira Júnior

    2016-02-01

    Full Text Available Clostridium perfringens is a microorganism commonly found in the microbiota of humans and animals and a potential cause of enteric, muscle or nervous diseases. The treatment of these diseases is based on antimicrobial therapy and it is extremely important to know the antimicrobial susceptibility profile of the strains present in the region. The aim of this study was to evaluate the antimicrobial susceptibility of C. perfringens isolated from domestic and wild animals in Brazil against seven different antimicrobials. Forty-one strains from the stool samples of cattle (n = 12, buffalo (n = 2, goat (n = 3, dogs (n = 12 and wild carnivores (n = 12 were examined. The minimum inhibitory concentration was determined by the agar dilution method using Brucella agar supplemented with 5% of sheep blood, 0.1% of vitamin K, 0.1% of hemin and concentrations ranging from 0,25 to 256,0 mg L-1 of the following antibiotics: erythromycin, florfenicol, metronidazole, oxytetracycline, penicillin, tylosin, and vancomycin. All C. perfringens strains were susceptible to florfenicol, metronidazole, penicillin and vancomycin. Two strains (4.9% were resistant to erythromycin and tylosin, while five (12.2% were resistant to oxytetracycline, one of which (2.4% from an ocelot.

  5. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals

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    Zeynab Golshani

    2012-11-01

    Full Text Available Please cite this article as: Golshani Z, Ahadi AM, Sharifzadeh A. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals. Arch Hyg Sci 2012;1(2:48-53. Abstract: Background & Aims of the Study: The aim of this study was to detect and survey the antibiotic resistance pattern of Pseudomonas (P. aeruginosa isolated from patients in Isfahan (located in central Iran hospitals. Materials & Methods : A Total of 50 clinical isolates of P. aeruginosa were collected from urine, wound, trachea, ear swab, and pus, and then were confirmed by standard tests. Antibiotic susceptibility was determined by the Kirby-Bauer disc diffusion method. Susceptibility data were compared by chi-square test using SPSS version 15. Results: Among the isolated strains, resistance to oxacillin was seen in 100%, ceftriaxone in 76%, amikacin in 70%, ceftazidime in 68%, cefepime in 68%, tobramycin in 62%, gentamicin in 60%, ciprofloxacin in 58%, and imipenem in 58% of the isolates. Conclusions: Comparison of the results showed that, patterns of antibiotic resistance are different from one hospital to another in various areas. Therefore, it is suggested that such studies should be performed in different hospitals. Also, prescribing correct medications is essential to prevent further increases in resistant bacteria. References: 1. Pagani L, Mantengoli E, Migliavacca R, Nucleo E, Pollini S, Spalla M, et al. Multifocal Detection of Multidrug-Resistant Pseudomonas aeruginosa Producing the PER-1 Extended- Spectrum β-Lactamase in Northern Italy. J Clin Microbiol 2004;42(6:2523–9. 2. Ling TKW, Xiong J, Yu Y, Lee CC, Ye H, Hawkey PM, et al. Multicenter Antimicrobial Susceptibility Survey of Gram-Negative Bacteria Isolated from Patients with Community-Acquired Infections in the People's Republic of China. Antimicrob Agents Chemother 2006;50(1:374–8. 3. Gupta V, Datta P, Agnihotri N, Chander J. Comparative in vitro Activities of Seven

  6. Evaluation of Ciprofloxacin as a Representative of Veterinary Fluoroquinolones in Susceptibility Testing

    OpenAIRE

    Riddle, Christa; Lemons, Carol L.; Papich, Mark G.; Altier, Craig

    2000-01-01

    Currently in veterinary medicine, ciprofloxacin is often used in susceptibility testing to represent the entire class of fluoroquinolone antimicrobials. Using quality control organisms as well as clinical isolates, we compared the MIC of ciprofloxacin to those of three other fluoroquinolones used in animals and found that ciprofloxacin is not an adequate representative of other members of this class.

  7. Meat industry wastewater: microbiological quality and antimicrobial susceptibility of E. coli and Salmonella sp. isolates, case study in Vojvodina, Serbia.

    Science.gov (United States)

    Stošić, Milena; Čučak, Dragana; Kovačević, Srđan; Perović, Marija; Radonić, Jelena; Sekulić, Maja Turk; Miloradov, Mirjana Vojinović; Radnović, Dragan

    2016-01-01

    Wastewater from meat processing industries is a fusion of compounds with a high load of organic matter, and pathogen microorganisms like Escherichia coli, and Salmonella sp. The aim of this research was to determine microbiological characteristics of the wastewater discharged from the meat processing industry in order to get a more detailed insight into meat industry wastewater pollution, and to evaluate the resistance of bacterial strains E. coli and Salmonella sp. to antibiotics. The evaluation of the antimicrobial susceptibility was performed on 37 strains of E. coli and eight strains of Salmonella sp. to nine different antibiotics. The number of faecal pollution indicators was very high in all samples. From a total of 37 strains of E. coli, a moderate degree of resistance was shown to tetracycline (37.83%); a low degree of resistance to ampicillin (21.62%), streptomycin (24.32%), trimethoprim-sulfamethoxazol (18.92%) and nalidixic acid (16.22%); and very low to: chloramphenicol (13.51%), ciprofloxacin (2.7%), gentamicin and cefotaxime (0.0%). The results for eight strains of Salmonella sp. show that all eight isolates had some degree of susceptibility to nine tested antimicrobial agents and six strains were fully susceptible to all tested antibiotics. PMID:27191574

  8. Diversity and antimicrobial susceptibility profiling of staphylococci isolated from bovine mastitis cases and close human contacts.

    Science.gov (United States)

    Schmidt, T; Kock, M M; Ehlers, M M

    2015-09-01

    The objectives of this study were to examine the diversity of Staphylococcus spp. recovered from bovine intramammary infections and humans working in close contact with the animals and to evaluate the susceptibility of the staphylococcal isolates to different antimicrobials. A total of 3,387 milk samples and 79 human nasal swabs were collected from 13 sampling sites in the KwaZulu-Natal province of South Africa. In total, 146 Staph. aureus isolates and 102 coagulase-negative staphylococci (CNS) were recovered from clinical and subclinical milk samples. Staphylococcusaureus was isolated from 12 (15.2%) of the human nasal swabs and 95 representative CNS were recovered for further characterization. The CNS were identified using multiplex-PCR assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and tuf gene sequencing. Seven Staphylococcus spp. were identified among the CNS of bovine origin, with Staph.chromogenes (78.4%) predominating. The predominant CNS species recovered from the human nasal swabs was Staph.epidermidis (80%) followed by Staph.chromogenes (6.3%). The antimicrobial susceptibility of all staphylococcal isolates was evaluated using disk diffusion and was supplemented by screening for specific antimicrobial resistance genes. Ninety-eight (67.1%) Staph.aureus isolates of bovine origin were pansusceptible; 39 (26.7%) isolates were resistant to a single class, and 7 (4.8%) isolates were resistant to 2 classes of antimicrobials. Two Staph. aureus (1.4%) isolates were multidrug-resistant. Resistance to penicillin was common, with 28.8% of the bovine and 75% of the human Staph. aureus isolates exhibiting resistance. A similar observation was made with the CNS, where 37.3% of the bovine and 89.5% of the human isolates were resistant to penicillin. Multidrug-resistance was common among the human CNS, with 39% of the isolates exhibiting resistance to 3 or more classes of antimicrobials. The antimicrobial

  9. Prevalence, genetic diversity, and antimicrobial susceptibility profiles of Staphylococcus aureus isolated from bovine mastitis in Zhejiang Province, China

    Institute of Scientific and Technical Information of China (English)

    Jian-ping LI; Hai-jian ZHOU; Lin YUAN; Ting HE; Song-hua HU

    2009-01-01

    This study was conducted to determine genetic diversity and antimicrobial susceptibility profiles of Staphylococcusaureus recovered from bovine mastitis in Zhejiang Province, China. Out of 3178 quarter milk samples from 846 lactating cows, among which 459 cows (54.3%) were found HMT positive, 890 quarters (28%) were found having subclinical mastitis. From 75 representative S. aureus isolates, 16 distinct types were identified by pulsed-field gel electrophoresis (PFGE). Four major PFGE types (A, B, C, and D) accounted for 82.7% of all isolates, and type A (41.3%) was observed in multiple herds across the studied areas. Each region was found to have a predominant type: Hangzhou type A (64.1%), Ningbo type C (34.5%) and type B (23.1%), Jinhua type D (53.3%), and Taizhou type C (62.5%). Results of antimicrobial susceptibility tests showed that 90.7% of the isolates were resistant to at least one antimicrobial. Resistance to penicillin and ampicillin (77.3%), tetracycline (60.0%), or erythromycin (48.0%) was observed. The bacteria resistant to multiple antibiotics such as penicillin, ampicillin, tetracycline, and erythromycin were commonly found. The information obtained from this study is useful for designing specific control programs for bovine S. aureus mastiffs in this region.

  10. Antimicrobial Susceptibility of Common Bacterial Pathogens Isolated from a New Regional Hospital in Southern Taiwan.

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    Hung-Ming Chen

    2003-12-01

    Full Text Available Background: Antimicrobial resistance has become a major health problem in Taiwan.While some trends in antimicrobial resistance are universal, others appear tobe unique for specific regions.Methods: To determine the distribution and antimicrobial drug resistance of bacterialpathogens in a new hospital in southern Taiwan, surveillance data on majorbacterial pathogens isolated from Chang Gung Memorial Hospital at Chia-Yifrom January 2002 through December 2002 were retrospectively analyzed.Results: The most common gram-positive isolate was Staphylococcus aureus.Escherichia coli and Klebsiella pneumoniae were the two most commongram negative isolates. Pseudomonas aeruginosa ranked the first amonggram-negative, glucose non-fermenting isolates, followed in the order of frequencyby Acinetobacter baumannii. Oxacillin resistance rate of S. aureuswas 58%, while vancomycin and teicoplanin remained effective against all ofthe isolates. The penicillin non-susceptibility rate of Streptococcus pneumoniaewas 52%, and it is notable that the rate of resistance to erythromycinwas 87%. Resistance to various antimicrobial agents for P. aeruginosa,Aeromonas hydrophila, and gram-negative enteric bacilli was very commonin our study. Infections caused by multidrug-resistant A. baumannii was notuncommon in this hospital but fortunately, imipenem resistant A. baumanniiwas rarely encountered. Antimicrobial resistance was common in nontyphoidSalmonella, S. choleraesuis and serogroup B isolates in particular.Conclusion: The high rates of antimicrobial resistance among these major bacterialpathogens in this new hospital are impressive and alarming. Judicious use ofantimicrobial agents can never be overemphasized. Continued surveillanceof the changes of resistance patterns over time is necessary.

  11. Prevotella intermedia and Porphyromonas gingivalis isolated from osseointegrated dental implants: colonization and antimicrobial susceptibility Prevotella intermedia e Porphyromonas gingivalis isolados de implantes osseointegrados: colonização e susceptibilidade a antimicrobianos

    OpenAIRE

    Eduardo Augusto Pfau; Mario Julio Avila-Campos

    2005-01-01

    The colonization and antimicrobial susceptibility of P. intermedia and P. gingivalis isolated from peri-implant and gingival sulcus samples were determined. Samples were collected from 30 patients submitted to implant in three different times: at the moment of the surgery, 20 and 60 days after the implant installation. Organisms were identified by using a biochemical tests or API 32-A kit and by PCR. The antimicrobial susceptibility was determined by using an agar dilution method. Nineteen P....

  12. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shrimps in Malaysia

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    Vengadesh eLetchumanan

    2015-01-01

    Full Text Available Vibrio parahaemolyticus is a marine and estuarine bacterium that has been the leading cause of foodborne outbreaks which leads to a significant threat to human health worldwide. Consumption of seafood contaminated with Vibrio parahaemolyticus causes acute gastroenteritis in individuals. The bacterium poses two main virulence factor including the thermostable direct hemolysin (tdh which is a pore-forming protein that contributes to the invasiveness of the bacterium in humans and TDH-related hemolysin (trh, which plays a similar role as thermostable direct hemolysin (tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance Vibrio parahaemolyticus strains in shrimps purchased from wetmarkets and supermarkets. The toxR-based PCR assay indicated that a total of 57.8% (185/320 isolates were positive for V. parahaemolyticus. Only 10% (19/185 toxR-positive isolate exhibit the TDH-related hemolysin (trh gene and none of the isolates were tested positive for thermostable direct hemolysin (tdh. The MAR index was measured for 14 common antimicrobial agents. The results indicated 98% of the isolates were highly susceptible to imipenem, ampicillin sulbactam (96%, chloramphenicol (95%, trimethoprim-sulfamet (93%, gentamicin (85%, levofloxacin (83% and tetracycline (82%. The chloramphenicol (catA2 and kanamycin (aphA-3 resistance genes were detected in the resistant V. parahaemolyticus isolates. Our results demonstrate that shrimps are contaminated with V. parahaemolyticus, some of which carry the trh-gene thus being potential to cause food borne illness. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields.

  13. Prevalence of uropathogens and antimicrobial susceptibility profile in outpatient from Jataí-GO

    Directory of Open Access Journals (Sweden)

    Dayane Moraes

    2014-06-01

    Full Text Available Introduction: Urinary tract infections (UTIs affect people worldwide. Escherichia coli is the main agent of UTI, however the etiology may vary according to the age and sex of the patient. Regional variations in the prevalence and antimicrobial resistance should be considered for therapy choice. Objectives: This study aimed to conduct a survey on the main agents of UTI, and assess the resistance of these microorganisms, during the period of March 2010 to June 2012 in the city of Jataí-GO. Method: A retrospective cross-sectional study were performed, collecting data on the prevalence of uropathogens and their sensitivity profiles which were evaluated by disk diffusion method. Results: During this period, 2,181 urine cultures were evaluated, of which 510 (23.4% were positive, predominantly female (81.4% and aged between 21 and 64 years old (59.7%. The most frequently isolated microorganism was E. coli (61%, followed by Staphylococcus saprophyticus (9.4%, and Proteus (9.4%. The prevalence of these bacteria according to the patient sex has suffered a statistically significant change (p < 0.05. It was possible to detect high resistance rate of E. coli to some antibiotics of choice for UTI treatment, such as ampicillin (57.9 %, pipemidic acid (50.5 %, nalidixic acid (48.6 %, and trimethoprim-sulfamethoxazole (44.8%. Conclusion: These data demonstrate the need to know the reality of each region in order to establish an appropriate empirical therapy, when it is not possible to perform culture and antimicrobial susceptibility testing.

  14. Antimicrobial susceptibility of Staphylococcus aureus isolated from bovine mastitis in Europe and the United States

    DEFF Research Database (Denmark)

    De Oliveira, A. P.; Watts, J. L.; Salmon, S. A.; Aarestrup, Frank Møller

    2000-01-01

    (123), Switzerland (69), United States (53), and Zimbabwe (6). The antimicrobial agents tested were penicillin, ampicillin, oxacillin, cephalothin, ceftiofur, amoxicillin + clavulanate, penicillin + novobiocin, enrofloxacin, premafloxacin, erythromycin, clindamycin, lincomycin, pirlimycin, neomycin...

  15. Urinary Escherichia coli antimicrobial susceptibility profiles and their relationship with community antibiotic use in Tasmania, Australia.

    Science.gov (United States)

    Meumann, Ella M; Mitchell, Brett G; McGregor, Alistair; McBryde, Emma; Cooley, Louise

    2015-10-01

    This study assessed urinary Escherichia coli antibiotic susceptibility patterns in Tasmania, Australia, and examined their association with community antibiotic use. The susceptibility profiles of all urinary E. coli isolates collected in Tasmania between January 2010 and December 2012 were included. The amount of Pharmaceutical Benefits Scheme (PBS)-subsidised use of amoxicillin, amoxicillin/clavulanic acid (AMC), cefalexin, norfloxacin, ciprofloxacin and trimethoprim was retrieved (at the Tasmanian population level) and the number of defined daily doses per 1000 population per day in Tasmania for these antibiotics was calculated for each month during the study period. Antimicrobial susceptibility data were assessed for changes over time in the 3-year study period. Antimicrobial use and susceptibility data were assessed for seasonal differences and lag in resistance following antibiotic use. Excluding duplicates, 28145 E. coli isolates were included. Resistance levels were low; 35% of isolates were non-susceptible to amoxicillin, 14% were non-susceptible to trimethoprim and cefalexin, gentamicin and norfloxacin. Amoxicillin use increased by 35% during winter/spring compared with summer/autumn, and AMC use increased by 21%. No seasonal variation in quinolone use or resistance was detected. The low levels of antimicrobial resistance identified may relate to Tasmania's isolated geographical location. Significant seasonal variation in amoxicillin and AMC use is likely to be due to increased use of these antibiotics for treatment of respiratory tract infections in winter. Quinolone use is restricted by the PBS in Australia, which is the likely explanation for the low levels of quinolone use and resistance identified. PMID:26187365

  16. Prevalence, serovars and antimicrobial susceptibility of Salmonella spp. from wild and domestic green iguanas (Iguana iguana) in Grenada, West Indies.

    Science.gov (United States)

    Sylvester, W R B; Amadi, V; Pinckney, R; Macpherson, C N L; McKibben, J S; Bruhl-Day, R; Johnson, R; Hariharan, H

    2014-09-01

    Cloacal swabs from 62 green iguanas (Iguana iguana), including 47 wild and 15 domestic ones from five parishes of Grenada, were sampled during a 4-month period of January to April 2013 and examined by enrichment and selective culture for the presence of Salmonella spp. Fifty-five per cent of the animals were positive, and eight serovars of Salmonella were isolated. The most common serovar was Rubislaw (58.8%), a serovar found recently in many cane toads in Grenada, followed by Oranienburg (14.7%), a serovar that has been causing serious human disease outbreaks in Japan. Serovar IV:48:g,z51 :- (formerly, S. Marina) highly invasive and known for serious infections in children in the United States, constituted 11.8% of the isolates, all of them being from domestic green iguanas. Salmonella Newport, a serovar recently found in a blue land crab in Grenada, comprised 11.8% of the isolates from the green iguanas. The remaining four less frequent serovars included S. Javiana and S. Glostrup. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim-sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, mainly to streptomycin, tetracycline and cefotaxime. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars from wild and domestic green iguanas in Grenada, West Indies. PMID:24325463

  17. Antimicrobial susceptibility and tetracycline resistance determinant genotyping of Gallibacterium anatis

    DEFF Research Database (Denmark)

    Bojesen, Anders M.; Vazquez, Maria E.; Bager, Ragnhild J.;

    2011-01-01

    . Multidrug resistance (resistance towards≥three drugs) was observed for 65% of the field strains and only two strains were susceptible to all compounds. Most prominently, resistance to tetracycline and sulfamethoxazole was observed in 92% and 97% of the field strains, respectively. For comparison these...... figures were 67% and 42%, respectively, for the reference strains.Genotyping of tetracycline resistance determinants was performed with primers specific for tet(A–E, H, K–M, O). Strains positive for tet(B), tet(H) and tet(L) were identified, however, in 20 out of 49 tetracycline resistant strains no...... the tetracycline resistance determinants in the remaining 41% of strains where no determinant was assigned....

  18. European surveillance study on antimicrobial susceptibility of Gram-positive anaerobic cocci

    DEFF Research Database (Denmark)

    Brazier, J; Chmelar, D; Dubreuil, L;

    2008-01-01

    Gram-positive anaerobic cocci (GPAC) are a heterogeneous group of microorganisms frequently isolated from local and systemic infections. In this study, the antimicrobial susceptibilities of clinical strains isolated in 10 European countries were investigated. After identification of 299 GPAC to...... Parvimonas micra (formerly Peptostreptococcus micros), isolated from skin and soft tissue infections. All isolates were susceptible to imipenem, metronidazole, vancomycin and linezolid. Twenty-one isolates (7%) were resistant to penicillin (n=13) and/or to clindamycin (n=12). Four isolates were resistant to...... both agents. The majority of resistant isolates were identified as F. magna and originated from blood, abscesses and soft tissue infections....

  19. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals

    OpenAIRE

    Zeynab Golshani; Ali Mohammad Ahadi; Ali Sharifzadeh

    2012-01-01

    Please cite this article as: Golshani Z, Ahadi AM, Sharifzadeh A. Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Patients Referring to Hospitals. Arch Hyg Sci 2012;1(2):48-53. Abstract: Background & Aims of the Study: The aim of this study was to detect and survey the antibiotic resistance pattern of Pseudomonas (P.) aeruginosa isolated from patients in Isfahan (located in central Iran) hospitals. Materials & Methods : A Total of 50 clinical isola...

  20. Evaluation of Antimicrobial Susceptibility of Enterobacteriaceae Causing Urinary Tract Infections in Africa

    OpenAIRE

    Tansarli, Giannoula S.; Athanasiou, Stavros; Falagas, Matthew E.

    2013-01-01

    Our objective was to evaluate the antimicrobial susceptibility of Enterobacteriaceae causing urinary tract infections (UTIs) in adults in Africa. The PubMed database was systematically searched to identify relevant studies published after 2000. Google, World Health Organization, and African Field Epidemiology networks were also searched. Twenty-eight studies, accounting for 381,899 urine isolates from 14 African countries, met the inclusion criteria. Escherichia coli, Klebsiella spp., and Pro...

  1. Stenotrophomonas maltophilia infections in a general hospital: patient characteristics, antimicrobial susceptibility, and treatment outcome.

    Directory of Open Access Journals (Sweden)

    George Samonis

    Full Text Available INTRODUCTION: Stenotrophomonas maltophilia is acquiring increasing importance as a nosocomial pathogen. METHODS: We retrospectively studied the characteristics and outcome of patients with any type of S. maltophilia infection at the University Hospital of Heraklion, Crete, Greece, between 1/2005-12/2010. S. maltophilia antimicrobial susceptibility was tested with the agar dilution method. Prognostic factors for all-cause in-hospital mortality were assessed with multivariate logistic regression. RESULTS: Sixty-eight patients (median age: 70.5 years; 64.7% males with S. maltophilia infection, not related to cystic fibrosis, were included. The 68 patients were hospitalized in medical (29.4%, surgical (26.5%, hematology/oncology departments (23.5%, or the intensive care units (ICU; 20.6%. The most frequent infection types were respiratory tract (54.4%, bloodstream (16.2%, skin/soft tissue (10.3%, and intra-abdominal (8.8% infection. The S. maltophilia-associated infection was polymicrobial in 33.8% of the cases. In vitro susceptibility was higher to colistin (91.2%, trimethoprim/sulfamethoxazole and netilmicin (85.3% each, and ciprofloxacin (82.4%. The empirical and the targeted treatment regimens were microbiologically appropriate for 47.3% and 63.6% of the 55 patients with data available, respectively. Most patients received targeted therapy with a combination of agents other than trimethoprim/sulfamethoxazole. The crude mortality and the mortality and the S. maltophilia infection-related mortality were 14.7% and 4.4%, respectively. ICU hospitalization was the only independent prognostic factor for mortality. CONCLUSION: S. maltophilia infection in a general hospital can be associated with a good prognosis, except for the patients hospitalized in the ICU. Combination reigmens with fluoroquinolones, colistin, or tigecycline could be alternative treatment options to trimethoprim/sulfamethoxazole.

  2. Prevalence and Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Nasal Carriers

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    Hedieh Moradi-Tabriz

    2015-10-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major virulence factors of hospital and community acquired infections. Healthcare workers can be the host of S.aureus for many months. And it is very important due to the possibility of transmission to patients. Theaim of this study was to determine the prevalence of S.aureus nasal carriers, the antibiotic susceptibility pattern and its effective factors on Sina Hospital workers in Tehran, Iran.Methods: healthcare workers from different wards of Sina Hospital were studied in Tehran, Iran in 2010. Samples were taken from both nostrils of each individual. After 18-24hr incubation, the isolates were evaluated by gram stain, catalase, coagulase, DNase and manitol salt agar bywhich staphylococci were isolated. Disk diffusion antimicrobial susceptibility tests against oxacillin, cefoxitin and vancomycin was performed. Finally, by using PCR, the mecA gene was studied in methicillin-resistant strains (MRSA.Results: 34of the 166 workers, were nasal carriers of S. aureus and one of them was MRSA. The ratio of carriers in operating room workers was more than other wards, without significant relationship (p.value>0.05. S.aureus was found in 34.3% of operating room, 13.8% of nurses and 22.7% of licensed and other personnel. There was a significant relationship betweenoccupations and S.aureus carriage (p.value:0.03.Conclusion: According to the low prevalence of S. aureus and MRSA carriers in Sina hospital, it can be said that the role of the hospital staff as a source of infections caused by S. aureus especially is very low.

  3. Antimicrobial susceptibilities and bacteriological characteristics of bovine Pseudomonas aeruginosa and Serratia marcescens isolates from mastitis.

    Science.gov (United States)

    Ohnishi, Mamoru; Sawada, Takuo; Hirose, Kazuhiko; Sato, Reiichiro; Hayashimoto, Mizuki; Hata, Eiji; Yonezawa, Chizuko; Kato, Hajime

    2011-12-29

    The presence of metallo-β-lactamase (MBL)-producing and multidrug-resistant Pseudomonas aeruginosa (MDRP) strains among bovine isolates of Gram-negative bacilli, and O-serotypes of bovine Serratia marcescens and P. aeruginosa isolates have been reported rarely. The aims of this study were to (1) elucidate antimicrobial susceptibilities and O-serotypes of P. aeruginosa and S. marcescens isolates from bovine mastitis and the presence of MBL-producers and MDRP strains among them and (2) evaluate their relationships to human isolates. We investigated the MICs of 24 antimicrobials and O-serotypes for 116 P. aeruginosa and 55 S. marcescens isolates in Japan, primarily in 2006. A total of 171 isolates exhibited high antimicrobial susceptibilities with the exception of a partial drug. P. aeruginosa isolates exhibited high susceptibilities of ≥ 95.7% to ciprofloxacin, imipenem, meropenem, piperacillin, ceftazidime, cefepime, cefoperazone/sulbactam, amikacin, tobramycin, and gentamicin; however, they exhibited a susceptibility of only 69.8% to aztreonam. They exhibited substantial resistances to ceftriaxone, enrofloxacin, cefotaxime, and moxalactam. S. marcescens isolates exhibited high susceptibilities of ≥ 90.9% to kanamycin, ceftiofur, sulfamethoxazole-trimethoprim, and the 15 aforementioned drugs, but exhibited resistance to minocycline. Neither MBL-producers nor MDRP strains were detected among the 171 strains. The dominant serotypes of P. aeruginosa isolates were OG, OA, OB, OI, OF, OE, and OK; those of S. marcescens isolates were O6 and O5. Every S. marcescens isolate was pigmented. These findings suggest that bovine P. aeruginosa and S. marcescens isolates differ from human isolates from both antibiogram and phenotypic perspectives, and could help to evaluate differences in bacteriological characteristics between bovine and human isolates. PMID:21783330

  4. Proteases (caseinase and elastase, hemolysins, adhesion and susceptibility to antimicrobials of Stenotrophomonas maltophilia isolates obtained from clinical specimens

    Directory of Open Access Journals (Sweden)

    Garcia Doroti de Oliveira

    2002-01-01

    Full Text Available Forty-six S. maltophilia isolates obtained from hospital clinical specimens were studied for protease (caseinase and elastase production, hemolytic activity, adhesion to HEp-2 cells, plastic and glass. Susceptibility to antimicrobial agents was also evaluated. The majority of isolates were obtained from respiratory tract secretions of patients using medical devices. All the isolates grown overnight were able to hydrolyze casein at 30masculineC and 37masculineC. After 72h, all the isolates hydrolyzed elastase at 30masculineC and 40 isolates (87% at 37masculineC. Most of the isolates presented hemolytic activity after 96h of incubation at both temperatures. Rabbit blood showed the hightest hemolytic activity, after 96h 61% and 98% of tested isolates presented beta-hemolysis at 30masculineC and 37masculineC, respectively. All isolates were susceptible to trimethoprim-sulfametoxazole and were resistant to most beta-lactams tested. By the dilution method, S. maltophilia showed a high susceptibility to ticarcillin-clavulanate and a lower susceptibility to ciprofloxacin than the agar diffusion. The isolates showed adhesion to HEp-2 cells, plastic and glass. The proteolytic activities and adhesion to inanimate surfaces detected in S. maltophilia can be related to the pathogenesis of this bacterium and/or medical device colonization which favors the development of nosocomial infections.

  5. Sensititre autoreader for same-day breakpoint broth microdilution susceptibility testing of members of the family Enterobacteriaceae.

    OpenAIRE

    Doern, G V; Staneck, J L; Needham, C.; Tubert, T

    1987-01-01

    The Sensititre Autoreader system is an instrument-assisted broth microdilution susceptibility test procedure based on the detection of fluorogenic growth substrate metabolism by test bacteria with different concentrations of antimicrobial agents. In the current investigation, this system was assessed as a means for predicting the in vitro activity of 17 antimicrobial agents versus numerous species of the family Enterobacteriaceae and Pseudomonas aeruginosa by using a breakpoint broth microdil...

  6. Antimicrobial susceptibility pattern of bacteria isolated from patients with urinary tract infection

    International Nuclear Information System (INIS)

    To determine the antimicrobial susceptibility pattern of bacterial pathogens in the patients of urinary tract infection reporting at a tertiary care hospital. Study Design: Laboratory based study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from January to December 2012. Methodology: A total of 440 culture positive bacterial isolates from 1110 urine samples; submitted over a period of one year were included in this study. Identification of bacterial isolates was done by standard biochemical profile of the organisms. The antimicrobial susceptibility of culture positive bacterial isolates was performed by disk diffusion method as recommended by Clinical Laboratory Standard Institute guidelines (CLSI). Results: Out of the 440 culture positive urine samples, 152 (34.6%) were from indoor patients whereas 288 (65.4%) from outdoor patients. Gram negative bacteria accounted for 414 (94%) of the total isolates while rest of the 26 (6%) were Gram positive bacteria. The most prevalent bacterial isolate was Escherichia (E.) coli 270 (61.3%) followed by Pseudomonas (P.) aeruginosa 52 (12%) and Klebsiella (K.) pneumoniae 42 (9.5%). The susceptibility pattern of E. coli showed that 96.2% of the bacterial isolates were sensitive to imipenem, 85.1% to amikacin, 80.7% to piperacillin/tazobactam and 72.6% to nitrofurantoin. In case of P. aeruginsosa, 73% bacterial isolates were sensitive to tazobactam/piperacillin, 69.2% to sulbactam/cefoperazone and 65.38% to imipenem. The antibiogram of K. pneumoniae has revealed that 76.1% of the bacterial isolates were sensitive to imipenem and 52.3% to piperacillin/tazobactam. Nitrofurantoin and imipenem were the most effective antimicrobials amongst the Enterococcus spp. as 92.3% showed susceptibility to this bacterial isolate. Conclusion: Majority of the bacterial isolates were sensitive to imipenem and piperacillin/tazobactam while susceptibility to most of the commonly used oral

  7. Prevalence, Molecular Characterization, and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus Isolated from Milk and Dairy Products.

    Science.gov (United States)

    Al-Ashmawy, Maha Abdou; Sallam, Khalid Ibrahim; Abd-Elghany, Samir Mohammed; Elhadidy, Mohamed; Tamura, Tomohiro

    2016-03-01

    The present work was undertaken to study the prevalence, molecular characterization, virulence factors, and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) in raw milk and dairy products in Mansoura City, Egypt. MRSA was detected in 53% (106/200) among all milk and dairy products with prevalence rates of 75%, 65%, 40%, 50%, and 35% in raw milk, Damietta cheese, Kareish cheese, ice cream, and yogurt samples, respectively. The mean S. aureus counts were 3.49, 3.71, 2.93, 3.40, and 3.23 log10 colony-forming units (CFU)/g among tested raw milk, Damietta cheese, Kareish cheese, ice cream and yogurt, respectively, with an overall count of 3.41 log10 CFU/g. Interestingly, all recovered S. aureus isolates were genetically verified as MRSA strains by molecular detection of the mecA gene. Furthermore, genes encoding α-hemolysin (hla) and staphylococcal enterotoxins (sea, seb, sec) were detected in all isolates. The antimicrobial susceptibility pattern of recovered MRSA isolates against 13 tested antimicrobials revealed that the least effective drugs were penicillin G, cloxacillin, tetracycline, and amoxicillin with bacterial resistance percentages of 87.9%, 75.9%, 65.2%, and 55.6%, respectively. These findings suggested that milk and dairy products represent a potential infection risk threat of multidrug-resistant and toxigenic S. aureus in Egypt due to neglected hygienic practices during production, retail, or storage stages. These findings highlighted the crucial importance of applying more restrictive hygienic measures in dairy production in Egypt for food safety. PMID:26836943

  8. Antimicrobial susceptibility of Staphylococcus aureus and characterization of methicillin-resistant Staphylococcus aureus isolated from bovine mastitis in Korea.

    Science.gov (United States)

    Nam, Hyang-Mi; Lee, Ae-Li; Jung, Suk-Chan; Kim, Mal-Nam; Jang, Geum-Chan; Wee, Sung-Hwan; Lim, Suk-Kyung

    2011-02-01

    A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea. PMID:21034263

  9. Antimicrobial susceptibility of Staphylococcus pseudintermedius colonizing healthy dogs in Saskatoon, Canada.

    Science.gov (United States)

    Priyantha, Roshan; Gaunt, Mathew C; Rubin, Joseph E

    2016-01-01

    This study reports antimicrobial susceptibility of Staphylococcus pseudintermedius carried by healthy dogs in Saskatoon, and describes changes in antimicrobial resistance since a 2008 study. One hundred healthy dogs presenting to the wellness service at the Western College of Veterinary Medicine were screened for S. pseudintermedius by culturing rectal and pharyngeal swabs. Staphylococcus pseudintermedius was identified biochemically and antimicrobial minimum inhibitory concentrations were determined by broth microdilution. Methicillin resistance was confirmed by polymerase chain reaction (PCR) and sequencing of the mecA gene. Of 221 S. pseudintermedius isolates from 78 dogs, 7 were methicillin resistant. No resistance to the fluoroquinolones, nitrofurantoin, tigecycline, vancomycin, quinupristin-dalfopristin, linezolid, or daptomycin was identified. Of the 78 positive dogs, isolates resistant to penicillin were found in 78%, to ampicillin in 61% and to tetracycline in 26%; resistance to oxacillin, erythromycin, clindamycin, trimethoprim + sulfamethoxazole, chloramphenicol, and gentamicin was found in < 10% of dogs. Compared to the 2008 study, the frequency of resistance to all drugs increased, and the frequency of colonization with pan-susceptible isolates decreased from 46% to 30%. PMID:26740701

  10. Antimicrobial susceptibility of enterococci from Italian patients with infective endocarditis

    Directory of Open Access Journals (Sweden)

    Claudio Farina

    2010-03-01

    Full Text Available The epidemiological and clinical study “Studio Endocarditi Italiane” (SEI evaluated 947 cases of infective endocarditis in 2004-2008. Enterococcal aethiology was described in 11% cases.The aim of our study was to evacuate the in vitro activity of twelve antibiotics alone and in association against 20 strains (15 E. faecalis, 5 E. faecium. Results show the in vitro activity of tigecyicline, daptomicine and linezolid. Synergism is appreciated for ceftriaxone-fosfomycin (FICindex50=0.34, FICindex90=0.56 against E. faecalis and for imipenem-fosfomycin against E. faecium.The majority of the tested strains show addition using ampicillin-ceftriaxone (FICindex50=0.85, FICindex90=1.01 and moxifloxacin- tigecycline (FICindex50=0.77, FICindex90=1.96.

  11. NORMAL VAGINAL BACTERIAL FLORA OF GIANT PANDAS (AILUROPODA MELANOLEUCA) AND THE ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF THE ISOLATES.

    Science.gov (United States)

    Yang, Xin; Yang, Jiang; Wang, Hongning; Li, Caiwu; He, Yongguo; Jin, SenYan; Zhang, Hemin; Li, Desheng; Wang, Pengyan; Xu, Yuesong; Xu, Changwen; Fan, Chengyun; Xu, Lulai; Huang, Shan; Qu, Chunmao; Li, Guo

    2016-06-01

    To study the typical vaginal bacterial flora of giant pandas (Ailuropoda melanoleuca), we took vaginal swabs for the sake of bacterial isolation, from 24 healthy female giant pandas. A total of 203 isolates were identified, representing a total of 17 bacterial species. The most common bacteria isolated were Lactobacillus spp. (54.2%, 13/24), followed by Staphylococcus epidermidis (41.7%, 10/24) and Escherichia coli (33.3%, 8/24). Some opportunistic pathogenic bacteria, such as Peptostreptococcus spp., Klebsiella pneumoniae , and Proteus mirabilis , were also isolated but showed no pathology. Antimicrobial susceptibility testing of aerobic bacterial isolates was performed with the disk diffusion method. Of the 152 isolates, resistance was most frequently observed with chloramphenicol (17.8%), followed by tetracycline (14.5%), ciprofloxacin (12.5%), streptomycin (11.8%), and florfenicol (11.8%), whereas 7.2% were multidrug resistant. This is the first report of the normal culturable vaginal bacterial flora of giant pandas and the antimicrobial susceptibility patterns of the isolates. PMID:27468049

  12. NORMAL VAGINAL BACTERIAL FLORA OF GIANT PANDAS (AILUROPODA MELANOLEUCA) AND THE ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF THE ISOLATES.

    Science.gov (United States)

    Yang, Xin; Yang, Jiang; Wang, Hongning; Li, Caiwu; He, Yongguo; Jin, SenYan; Zhang, Hemin; Li, Desheng; Wang, Pengyan; Xu, Yuesong; Xu, Changwen; Fan, Chengyun; Xu, Lulai; Huang, Shan; Qu, Chunmao; Li, Guo

    2016-03-01

    In order to study the typical vaginal bacterial flora of giant pandas (Ailuropoda melanoleuca), we took vaginal swabs for the sake of bacterial isolation, from 24 healthy female giant pandas. A total of 203 isolates were identified, representing a total of 17 bacterial species. The most common bacteria isolated were Lactobacillus spp. (54.2%, 13 of 24), followed by Staphylococcus epidermidis (41.7%, 10 of 24) and Escherichia coli (33.3%, 8 of 24). Some opportunistic pathogenic bacteria, such as Peptostreptococcus spp., Klebsiella pneumoniae, and Proteus mirabilis, were also isolated but showed no pathology. Antimicrobial susceptibility testing of aerobic bacterial isolates was performed with disk diffusion method. Of the 152 isolates, resistance was most frequently observed with chloramphenicol (17.8%), followed by tetracycline (14.5%), ciprofloxacin (12.5%), streptomycin (11.8%), and florfenicol (11.8%), while 7.2% were multidrug resistant. This is the first report of the normal vaginal culturable bacterial flora of giant pandas, followed by the antimicrobial susceptibility patterns of the isolates. PMID:27010307

  13. Susceptibilidad in vitro de Arcobacter butzleri a seis drogas antimicrobianas In vitro susceptibility of Arcobacter butzleri to six antimicrobial drugs

    Directory of Open Access Journals (Sweden)

    L. Otth

    2004-12-01

    Full Text Available Se determinaron los patrones de susceptibilidad de 50 cepas de A. butzleri mediante el método del E-test. Ninguna cepa fue resistente a gentamicina y tetraciclina, pero, hubo cepas resistentes a eritromicina (2% y ciprofloxacina (2%. Además, el 90 y el 98% de las cepas fueron resistentes a ampicilina y cloramfenicol respectivamente. Solamente dos de las 45 cepas ampicilina-resistentes fueron productoras de ß-lactamasa. Palabras clave: Arcobacter butzleri, susceptibilidad antimicrobiana, bacterias emergentes, E-test, ß-lactamasaThe susceptibility patterns of 50 A. butzleri strains to six antimicrobial agents were determined using the E-test method. No strain was found to be resistant to gentamicin and tetracycline, but two different strains (2% were resistant to erythromycin and ciprofloxacin. Ninety and 98% of the strains were resistant to ampicillin and chloramphenicol, respectively. Only two of the 45 ampicillin resistant strains were able to produce ß-lactamase.

  14. Species distribution and antimicrobial susceptibility of enterococci isolated from broilers infected experimentally with Eimeria spp and fed with diets containing different supplements

    Directory of Open Access Journals (Sweden)

    A.P.V. Cassenego

    2011-06-01

    Full Text Available Resistant bacteria in animal can be spread to environment and to humans. Poultry feed and infections caused by Eimeria spp. are important factors in determining the intestinal microbial communities. The aim of this study was to verify the prevalence of species and antimicrobial susceptibility of Enterococcus isolated from broilers fed with different supplements and infected experimentally with Eimeria spp. Broilers were divided in eight groups, fed with diets supplemented with a combination of antimicrobial, ionophore-coccidiostatics, probiotic, essential oil. At 14 days old all birds, except the control, received a solution containing oocysts of Eimeria spp. Samples of cloacal swabs from broilers were collected. A total of 240 Enterococcus sp. strains were isolated, confirmed genus by PCR, classified as species, tested for antimicrobial susceptibility and screened by PCR for the presence of tet(L, tet(M and erm(B genes. The overall distribution of species isolated from fecal samples was E. faecalis (40%, followed by E. casseliflavus/E. gallinarum (10.8%, E. mundtii (10.8%, E. faecium (10.8%, E. columbae (5.8% and E. gallinarum (4.2%. Changes in the composition or frequency of Enterococcus species were observed in all dietary supplementation. Antimicrobial susceptibility tests showed resistance phenotypes a range of antibiotics, especially used in humans such as, streptomycin, penicillin, rifampicin and vancomycin. There was no correlation between different supplementation for broilers and antimicrobial resistance and the presence of tet(M, tet(L and erm(B genes. Dietary supplementation had effect on the Enterococcus sp. colonization, but did not have significant effect on the phenotype and genotype of antimicrobial resistance in enterococci.

  15. Species distribution and antimicrobial susceptibility of enterococci isolated from broilers infected experimentally with Eimeria spp and fed with diets containing different supplements.

    Science.gov (United States)

    Cassenego, A P V; d'Azevedo, P A; Ribeiro, A M L; Frazzon, J; Van Der Sand, S T; Frazzon, A P G

    2011-04-01

    Resistant bacteria in animal can be spread to environment and to humans. Poultry feed and infections caused by Eimeria spp. are important factors in determining the intestinal microbial communities. The aim of this study was to verify the prevalence of species and antimicrobial susceptibility of Enterococcus isolated from broilers fed with different supplements and infected experimentally with Eimeria spp. Broilers were divided in eight groups, fed with diets supplemented with a combination of antimicrobial, ionophore-coccidiostatics, probiotic, essential oil. At 14 days old all birds, except the control, received a solution containing oocysts of Eimeria spp. Samples of cloacal swabs from broilers were collected. A total of 240 Enterococcus sp. strains were isolated, confirmed genus by PCR, classified as species, tested for antimicrobial susceptibility and screened by PCR for the presence of tet(L), tet(M) and erm(B) genes. The overall distribution of species isolated from fecal samples was E. faecalis (40%), followed by E. casseliflavus/E. gallinarum (10.8%), E. mundtii (10.8%), E. faecium (10.8%), E. columbae (5.8%) and E. gallinarum (4.2%). Changes in the composition or frequency of Enterococcus species were observed in all dietary supplementation. Antimicrobial susceptibility tests showed resistance phenotypes a range of antibiotics, especially used in humans such as, streptomycin, penicillin, rifampicin and vancomycin. There was no correlation between different supplementation for broilers and antimicrobial resistance and the presence of tet(M), tet(L) and erm(B) genes. Dietary supplementation had effect on the Enterococcus sp. colonization, but did not have significant effect on the phenotype and genotype of antimicrobial resistance in enterococci. PMID:24031659

  16. Molecular characterization and antimicrobial susceptibility of Streptococcus pneumoniae isolated from children hospitalized with respiratory infections in Suzhou, China.

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    Qian Geng

    Full Text Available BACKGROUND: Dissemination of antibiotic resistant clones is recognized as an important factor in the emergence and prevalence of resistance in pneumococcus. This study was undertaken to survey the antimicrobial susceptibility and serotypes distribution of pneumococci and to explore the circulating clones in hospitalized children in Suzhou, China. METHODS: The pneumococci were isolated from the nasopharyngeal aspirates of children less than 5 years of age admitted to Soochow-University-Affiliated-Children's-Hospital with respiratory infections. The capsular serotypes were identified by multiplex polymerase chain reaction (PCR. Antimicrobial susceptibility was tested by E-test. The presence of ermB, mefA/E genes were detected by PCR and the genotypes were explored by Multilocus sequence typing (MLST. RESULTS: From July 2012 to July 2013, a total of 175 pneumococcal isolates were collected and all strains were resistant to erythromycin and clindamycin, about 39.4% strains were non-susceptible to penicillin G. Overall, 174 (99.4% isolates were resistant to ≥ 3 types of antibiotics. Serotypes 19F (28.1%, 6B (19.7%, 19A (18.0%, and 23F (17.4% were the most common serotypes in all identified strains. The serotypes coverage of PCV7 and PCV13 were 71.9% and 89.9%, respectively. Four international antibiotic-resistant clones, including Taiwan19F-14 (n = 79, Spain23F-1(n = 25, Taiwan23F-15(n = 7 and Spain6B-2(n = 7, were identified. The Taiwan19F-14 clones have a higher non-susceptibility rate in β-lactams than other clones and non-clone isolates (p<0.001. In addition, 98.7% Taiwan19F-14 clones were positive of both ermB and mefA/E genes, compare to 33.3% in other clones and non-clone strains. CONCLUSIONS: The spread of international antibiotic-resistant clones, especially Taiwan19F-14 clones, played a predominant role in the dissemination of antimicrobial resistant isolates in Suzhou, China. Considering the high prevalence of PCV7 serotypes and

  17. Antimicrobial Non-Susceptibility of Escherichia coli from Outpatients and Patients Visiting Emergency Rooms in Taiwan.

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    Jann-Tay Wang

    Full Text Available Longitudinal nationwide surveillance data on antimicrobial non-susceptibility and prevalence of extended-spectrum β-lactamases (ESBLs as well as AmpC β-lactamases producers among Escherichia coli from different sources in the community settings are limited. Such data may impact treatment practice. The present study investigated E. coli from outpatients and patients visiting emergency rooms collected by the Taiwan Surveillance of Antimicrobial Resistance (TSAR program. A total of 3481 E. coli isolates were studied, including 2153 (61.9% from urine and 1125 (32.3% from blood samples. These isolates were collected biennially between 2002 and 2012 from a total of 28 hospitals located in different geographic regions of Taiwan. Minimum inhibitory concentrations (MIC were determined using methods recommended by the Clinical Laboratory Standards Institute (CLSI. The prevalence and factors associated with the presence of ESBL and AmpC β-lactamase-producers were determined. Significant increases in non-susceptibility to most β-lactams and ciprofloxacin occurred during the study period. By 2012, non-susceptibility to cefotaxime and ciprofloxacin reached 21.1% and 26.9%, respectively. The prevalence of ESBL- and AmpC- producers also increased from 4.0% and 5.3%, respectively, in 2002-2004, to 10.7% for both in 2010-2012 (P < 0.001. The predominant ESBL and AmpC β-lactamase genes were CTX-M and CMY-types, respectively. Non-susceptibility of urine isolates to nitrofurantoin remained at around 8% and to fosfomycin was low (0.7% but to cefazolin (based on the 2014 CLSI urine criteria increased from 11.5% in 2002-2004 to 23.9% in 2010-2012 (P <0.001. Non-susceptibility of isolates from different specimen types was generally similar, but isolates from elderly patients were significantly more resistant to most antimicrobial agents and associated with the presence of ESBL- and AmpC- β-lactamases. An additional concern is that decreased ciprofloxacin

  18. Isolamento e teste de susceptibilidade a antimicrobianos de bactérias em infecções uterinas de éguas Isolation and antimicrobial susceptibility of bacteria in uterine infections in mares

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    N. Silva

    1999-06-01

    Full Text Available Foram examinados 206 "swabs" cervicais e uterinos de éguas de várias raças, de diversas regiões do Estado de Minas Gerais, durante o período de 1986 a 1996. Cerca de 164 "swabs" foram positivos para a presença de microrganismos causadores de endometrites. Streptococcus equi subsp. zooepidemicus (25,7% e Escherichia coli (15,1% foram os principais agentes infecciosos isolados. Outros microrganismos presentes foram: Staphylococcus aureus (9,2%, Streptococcus alfa-hemolítico (9,2%, Pseudomonas aeruginosa (3,9%, Staphylococcus coagulase negativo (6,3%, Bacillus spp. (1,9%, Rhodococcus equi (3,4% e Proteus mirabilis (1,5%. As provas de susceptibilidade aos antimicrobianos revelaram que amicacina e gentamicina (70,2%, ampicilina (59,5% e cloranfenicol (59,5% foram os antibióticos de maior ação in vitro contra os microrganismos isolados.This study examined 206 cervical and uterine swabs collected from infected mares from herds in the Minas Gerais State, Brazil, from 1986 to 1996. Amongst 164 successful isolations, 25.7% were identified as Streptococcus equi, subsp. zooepidemicus, and 15.1% as Escherichia coli, both considered the most important isolates. Other bacteria found included Staphylococcus aureus (9.2%, Streptococcus alpha-hemolytic (9.2%, Pseudomonas aeruginosa (3.9%, coagulase negative Staphylococcus (6.3%, Bacillus spp. (1.9%, Rhodococcus equi (3.4% and Proteus mirabilis (1.5%. The antibiotic susceptibility tests revealed amikacin and gentamicin (70.2%, ampicillin and chloramphenicol (59.5% as the most effective in vitro antibiotics against these microorganisms.

  19. Serotyping, Genotyping, and Antimicrobial Susceptibility of Ornithobacterium rhinotracheale Isolates from Mexico.

    Science.gov (United States)

    Peña-Vargas, Edgar Rafael; Vega-Sánchez, Vicente; Morales-Erasto, Vladimir; Trujillo-Ruíz, Héctor Hugo; Talavera-Rojas, Martín; Soriano-Vargas, Edgardo

    2016-09-01

    The bacterium Ornithobacterium rhinotracheale is associated with respiratory disease and septicemia in poultry. In this study, 9 reference strains and a total of 23 isolates of O. rhinotracheale from respiratory diseased poultry from Mexico were serotyped and genotyped. Furthermore, the antimicrobial susceptibility of isolates and reference strains of O. rhinotracheale were determined. All isolates belong to serotype A and showed a clonal relationship. All reference strains and isolates were resistant to colistin, fosfomycin, gentamicin, kanamycin, streptomycin, and trimethoprim-sulfamethoxazole. These results should eventually be helpful in planning strategies for the control of O. rhinotracheale infections in poultry in Mexico. PMID:27610728

  20. Bacterial pathogens implicated in causing urinary tract infection (uti and their antimicrobial susceptibility pattern in Ethiopia

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    Theodros Getachew

    2010-01-01

    Full Text Available Introduction: Urinary Tract Infection (UTI is one of the most common infectious disease ranking next to upper respiratory tract infection is the cause of morbidity and mortality in human. They are mostly caused by bacteria. However, studies conducted in Ethiopia are few and are not extensive. Therefore, studying bacterial pathogens causing UTI and their drug susceptibility patterns is of a highest priority. Material & Methods: A total of 3228 urine samples were collected from 2004 to 2009. Fresh midstream urine samples were aseptically collected in sterile containers. Each sample was cultured onto 5% sheep blood agar and CLED agar plates using a calibrated loop, delivering 1ul of the sample. This was incubated at 37° C aerobically overnight. Bacterial isolates were identified using standard biochemical tests and antimicrobial susceptibility pattern was determined using the Kirby ¿ Bauer¿s disk diffusion method followed CLSI guidelines. Result & discussion: From a total of 3228 urine samples significant bacterial growth was obtained from 651 samples. The gram positive and negative bacteria accounted 17.7 % and 80.2% respectively, the rest 2.2 % are yeasts. The majority 475(72.9 of the isolates were from women while the remaining 176 (27.1 were from men. A wide spectrum of uropathogens was isolated, of which 359 (55.1 % were Escherichia coli, 107 (16.4 % Klebsiella species, 66 (10.1 % streptococcus species, 49(7.5% staphylococcus species, 14 (2.2 % citrobacter species, 14 (2.2 % candida species, 13 (2 % enterobacter species, 11 (1.7 % pseudomonas and the rest 2.8% are 5 proteus species, 5 salmonella species, 4 acinetobacter species and 4 M. morganii. Resistance rate to Gram-negative bacilli were 96 % to amoxicilline-clavulanic acid, 66.9 % to tetracycline, 61.4 % to ampicillin, 64.7 % to trimethoprimsulfamethoxazole, 37.6 % to chloramphenicol, 34 % to norfloxacine and 22.4 % to ceftriaxone. Among Gram-positive, 45.1 % were resistant to

  1. Extended Spectrum β-lactamases and antimicrobial susceptibility among clinical isolates of Pseudomonas aeruginosa in the West Bank, Palestine

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    Tamer Essawi

    2013-06-01

    Full Text Available Objectives: Class D oxacillinases are frequently acquired by gram negative bacteria in general and P. aeruginosa in particular.P. aeruginosa is commonly implicated in causing nosocomial infections. The evolution of antibiotic resistance inP. aeruginosa and the acquisition of blaOXA genes interfere with successful treatment.Methods: A total of 49 clinical isolates of P. aeruginosa were obtained from Rafidia Hospital, West Bank, Palestine.Antimicrobial susceptibility testing of the isolates was performed by the standard disc diffusion method following theguidelines of CLSI. The prevalence of class D β-lactamases (OXA groups I, II and III as well as the pseudomonas specificenzymes (CARB-3 were determined by PCR.Results: Susceptibility of P. aeruginosa to carbapenems was the highest 89%, and lowest to ticarcillin/clavulanic acid70%. This study revealed that P. aeruginosa produced oxacillinase enzymes at rates of: OXA-10 (40.8%, OXA-2 (20.4%and OXA-1 (18.4%. All ceftazidime resistant strains expressed OXA-1 and OXA-2, 18.4%. PSE group was expressed in10.2%.Conclusions: This is the first research conducted to investigate the correlation between OXA genes (blaOXA-1, bla-OXA-2 and blaOXA-10 and antimicrobial resistance among P. aeruginosa clinical isolates in Palestine. The results obtainedcould contribute to better treatment and reduction of the evolution of resistant strains. In addition, it will provideimportant information regarding the geographical distribution of class D β-lactamases. J Microbiol Infect Dis 2013; 3(2:56-60Key words: P. aeruginosa, β-lactamase, susceptibility, oxacillinases, blaOXA genes

  2. Antimicrobial Susceptibility of Udder Pathogens Isolated from Dairy Herds in the West Littoral Region of Uruguay

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    Franklin A

    2002-03-01

    Full Text Available A total of 522 strains belonging to streptococci, enterococci and staphylococci isolated from sub-clinical and clinical cases of bovine mastitis from the west littoral region of Uruguay were analysed for their susceptibility to several antimicrobial agents. The susceptibility patterns were studied by agar disk diffusion methods (ADDM and broth micro-dilution to determine the minimum inhibitory concentration (MIC. The concentration that inhibits 90% (MIC90 of the analysed strains reported in micrograms per millilitre, for Staphylococcus aureus were > 8, 8, ≤ 0.5, ≤ 4, ≤ 1, ≤ 0.5, > 64, ≤ 0.25, 0.5, ≤ 1 and ≤ 1 to penicillin, ampicillin, oxacillin, cephalotin, gentamicin, erythromycin, oxitetracycline, enrofloxacin, trimethoprim/sulfamethoxazole, neomycin, and clindamycin, respectively. Coagulase-negative staphylococci (CNS had different values for penicillin (4 and ampicillin (2, while the other antimicrobial agents had the same MIC90 values as reported for S. aureus. The MIC90 values for streptococci were 0.12, 0.25, ≤ 4, 16, ≤ 0.25, 0.5, 0.25 for penicillin, ampicillin, cephalotin, gentamicin, erythromycin, oxytetracycline and trimethoprim-sulfamethoxazole, whereas MIC90 for enterococci were 4, 4, 4, ≤ 0.5, 2, > 8 for penicillin, ampicillin, gentamicin, erythromycin, oxytetracycline and trimethoprim-sulfamethoxazole, respectively. Of 336 strains of S. aureus, 160 (47.6% were resistant to penicillin. For 41 CNS strains, 10 (27% presented penicillin-resistance. All the streptococcal strains were susceptible to penicillin, while 3 (7% of the 43 enteroccocal strains were resistant. Non significant statistical differences were found between the results obtained by ADDM and broth micro-dilution for classifying bacterial isolates as susceptible or resistant according to the National Committee of Clinical Laboratory Standards.

  3. Antimicrobial susceptibility of Staphylococcus aureus isolated from bovine mastitis in Europe and the United States

    DEFF Research Database (Denmark)

    De Oliveira, A. P.; Watts, J. L.; Salmon, S. A.;

    2000-01-01

    Minimum inhibitory concentrations were determined for 811 strains of Staphylococcus aureus isolated from cases of bovine mastitis in 11 countries. The countries and number of isolates included Denmark (105), England (92), Finland (95), Germany (103), Iceland (22), Ireland (42), Norway (101), Swed...... antimicrobial agents tested regardless of country. Given the differences in antimicrobial use in various countries, the widespread adoption of mastitis control programs to prevent infections limits the exposure of S. aureus infected animals to antimicrobial drugs.......Minimum inhibitory concentrations were determined for 811 strains of Staphylococcus aureus isolated from cases of bovine mastitis in 11 countries. The countries and number of isolates included Denmark (105), England (92), Finland (95), Germany (103), Iceland (22), Ireland (42), Norway (101), Sweden...

  4. PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ISOLATES IN A TERTIARY CARE HOSPITAL IN PUNJAB

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    Satish

    2013-10-01

    Full Text Available ABSTRACT: BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA is an important cause of nosocomial infections worldwide. This prospective study was undertaken to know the prevalence of MRSA, to study antimicrobial susceptibility pattern and inducible clindamycin resistance in Staphylococcus aureus isolates obtained from the indoor patients of a tertiary care hospital in Punjab. MATERIALS AND METHODS : All the iso lates of Staphylococcus aureus obtained from various clinical specimens were identified by standard methods. MRSA was detected using 30ug cefoxitin disc by disc diffusion method as per CLSI guidelines, 2007. Each isolate was tested for other anti - staphyloc occal antibiotics by Kirby - Bauer disc diffusion method. Additionally, inducible clindamycin resistance was studied by disc induction test (D test. RESULTS : During a period of one year, a total of 252 isolates of Staphylococcus aureus were obtained. Eighty six (34.1% isolates were methicillin resistant Staphylococcus aureus (MRSA and the remaining 166 (65.8% isolates were methicillin sensitive Staphylococcus aureus (MSSA. MRSA isolates were significantly less sensitive to common anti - staphylococcal anti biotics as compared to MSSA isolates. However, MRSA isolates showed relatively better sensitivity to some of the antibiotics like netilmicin, levofloxacin, tetracycline and clindamycin. Susceptibility to ciprofloxacin was low in both MSSA (19.8% and MRSA (9.3%. None of the isolate of Staphylococcus aureus was resistant to vancomycin, linezolid and teicoplanin. Inducible clindamycin resistance was present in 17 (19.7% MRSA isolates as against 8 (4.8% MSSA isolates. CONCLUSION : Robust antimicrobial stewa rdship and strengthened infection control measures are required to prevent spread and reduce emergence of resistance

  5. Properties and antimicrobial susceptibility of Trueperella pyogenes isolated from bovine mastitis in China.

    Science.gov (United States)

    Alkasir, Rashad; Wang, Jianfang; Gao, Jian; Ali, Tariq; Zhang, Limei; Szenci, Ottó; Bajcsy, Árpád Csaba; Han, Bo

    2016-03-01

    Trueperella (T.) pyogenes is an opportunistic pathogen that causes suppurative diseases in domestic animals. In this work, the properties, pathogenesis and phenotypic diversity of T. pyogenes isolates from bovine mastitis were studied. Both pyolysin (plo) and collagen-binding protein (cbp) virulence factor genes were detected by PCR in all T. pyogenes isolates (n = 50). Using the tissue culture plate method, 90% of T. pyogenes isolates were able to form biofilms. The minimum inhibitory concentrations (MICs) of 13 antimicrobials against T. pyogenes isolates were determined. High susceptibility was observed to rifampin (96%), ampicillin (94%), ciprofloxacin (94%), and penicillin (92%), while low susceptibility was found to trimethoprim-sulphamethoxazole (10%) and bacitracin (2%). The intracellular assay revealed that T. pyogenes isolates had different cytopathogenic effects on cells. The high percentage (28.6%) of T. pyogenes isolates suggests that this bacterium is an important contributor to mastitis. Moreover, the high occurrence of multidrug resistance, biofilm production, intracellular survival, and the temporal dynamics of T. pyogenes interactions are key factors for a better understanding of how immunity acts on infections with these bacteria and how they evade immune surveillance, thus highlighting the need for the prudent use of antimicrobial agents in veterinary medicine. PMID:26919137

  6. Susceptibilidade antimicrobiana de Campylobacter fetus subsp. venerealis isolado de bovinos Antimicrobial susceptibility of Campylobacter fetus subsp. venerealis isolated from cattle

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    Agueda C. Vargas

    2005-03-01

    Full Text Available A campilobacteriose venérea bovina, ocasionada principalmente pelo Campylobacter fetus subsp. fetus e Campylobacter subsp. venerealis, é transmitida através do coito ou por inseminação com sêmen contaminado. O propósito deste estudo foi determinar a susceptibilidade in vitro de isolados de C. fetus subesp. venerealis a agentes antimicrobianos comumente utilizados para o tratamento clínico e de sêmen. Foram testadas duas cepas padrão, sendo uma de C. fetus subsp. fetus e outra de C. fetus subsp. venerealis, bem como 21 amostras de isolados clínicos de C. fetus subsp. venerealis. Os testes foram realizados conforme o método de Kirby-Bauer. A amostra padrão de C. fetus subsp. fetus demonstrou-se resistente à lincomicina, penicilina e ácido nalidíxico, enquanto a de C. fetus subsp. venerealis apresentou susceptibilidade a todos antimicrobianos testados, com exceção do ácido nalidíxico. Todas as amostras de C. fetus subsp. venerealis foram susceptíveis à amicacina, ampicilina, cefalotina, estreptomicina, gentamicina, penicilina e tetraciclina. Foi observada resistência de 42,86% à lincomicina e 4,76 % a enrofloxacina, e de 100% ao ácido nalidíxico. Ainda, 4,76% apresentaram susceptibilidade intermediária à enrofloxacina, neomicina e polimixina B e 9,52% à lincomicina. Os resultados evidenciaram a sensibilidade das amostras analisadas aos antimicrobianos comumente utilizados para o tratamento clínico e do sêmen.Venereal campylobacteriosis is associated with infection of Campylobacter fetus subsp. fetus and Campylobacter fetus subsp. venerealis. The etiological agent is transmitted by natural bull breeding or artificial insemination using contaminated semen. The present study aimed to determine the in vitro susceptibility of C. fetus subsp. venerealis isolates to antimicrobial drugs generally used in clinical and semen treatment. Reference strains of C. fetus subsp. fetus and C. fetus subsp. venerealis and 21 C. fetus

  7. Frequency and Antimicrobial Susceptibility of Coagulasenegative Staphylococci Isolated from Bovine Mastitis in Dairy Farms from Tolima, Colombia

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    María del Pilar Sánchez Bonilla

    2015-09-01

    Full Text Available Objective: To determine the antimicrobial presence and susceptibility of the coagulase-negative staphylococci group (ECN, for its initials in Spanish in some cattle farms from Tolima, Colombia. Materials and methods: Using the California test for the diagnosis of mastitis (CMT, for its initials in Spanish, 484 quarters belonging to 121 cows from five small production ranches from a region of central Tolima were evaluated. CMT positive samples were cultivated for bacterial isolation. The ECN found were tested for susceptibility to the antibiotics. The results were analyzed with descriptive statistics. Results: 252 (52% quarters did not show any type of reaction to the CMT, nor did they show any clinical signs of mastitis, therefore they were considered free of the disease. From the quarters, 73 (15% turned positive for CMT and bacteriological culture. From these, 36 strains of ECN were isolated (7.4% of the total of quarters; S. aureus-ECP, 28 (5.8%; Streptococcus spp., 6 (1.2%.; Escherichia coli, 2 (0.4%, and Klebsiella pneumoniae, 2 (0.2%. The clinical and subclinical mastitis in the quarter occurred in 1.4% and 13.6%, respectively. In 5 (1.0% of the quarters, clinical mastitis caused by ECN was found and subclinical mastitis in 31 (6.4%. 61% of the ECN strains were resistant to penicillin, and 58%, to tetracycline; 97% were sensitive to cefoperazone. Conclusion: The ECN group, considered a global emergent of mastitis, is evidenced with high frequency in ranches from Tolima, Colombia, causing clinical and subclinical mastitis with varied response to antimicrobials.

  8. A two-hour antibiotic susceptibility test by ATP-bioluminescence.

    Science.gov (United States)

    March Rosselló, Gabriel Alberto; García-Loygorri Jordán de Urries, María Cristina; Gutiérrez Rodríguez, María Purificación; Simarro Grande, María; Orduña Domingo, Antonio; Bratos Pérez, Miguel Ángel

    2016-01-01

    The antibiotic susceptibility test (AST) in Clinical Microbiology laboratories is still time-consuming, and most procedures take 24h to yield results. In this study, a rapid antimicrobial susceptibility test using ATP-bioluminescence has been developed. The design of method was performed using five ATCC collection strains of known susceptibility. This procedure was then validated against standard commercial methods on 10 strains of enterococci, 10 staphylococci, 10 non-fermenting gram negative bacilli, and 13 Enterobacteriaceae from patients. The agreement obtained in the sensitivity between the ATP-bioluminescence method and commercial methods (E-test, MicroScan and VITEK2) was 100%. In summary, the preliminary results obtained in this work show that the ATP-bioluminescence method could provide a fast and reliable AST in two hours. PMID:25979598

  9. Comparative antimicrobial susceptibility of aerobic and facultative bacteria from community-acquired bacteremia to ertapenem in Taiwan

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    Fung Chang-Phone

    2007-07-01

    Full Text Available Abstract Background Ertapenem is a once-a-day carbapenem and has excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The susceptibility of isolates of community-acquired bacteremia to ertapenem has not been reported yet. The present study assesses the in vitro activity of ertapenem against aerobic and facultative bacterial pathogens isolated from patients with community-acquired bacteremia by determining and comparing the MICs of cefepime, cefoxitin, ceftazidime, ceftriaxone, ertapenem, piperacillin, piperacillin-tazobactam, ciprofloxacin, amikacin and gentamicin. The prevalence of extended broad spectrum β-lactamases (ESBL producing strains of community-acquired bacteremia and their susceptibility to these antibiotics are investigated. Methods Aerobic and facultative bacteria isolated from blood obtained from hospitalized patients with community-acquired bacteremia within 48 hours of admission between August 1, 2004 and September 30, 2004 in Chang Gung Memorial Hospital at Keelung, Taiwan, were identified using standard procedures. Antimicrobial susceptibility was evaluated by Etest according to the standard guidelines provided by the manufacturer and document M100-S16 Performance Standards of the Clinical Laboratory of Standard Institute. Antimicrobial agents including cefepime, cefoxitin, ceftazidime, ceftriaxone, ertapenem, piperacillin, piperacillin-tazobactam, ciprofloxacin, amikacin and gentamicin were used against the bacterial isolates to test their MICs as determined by Etest. For Staphylococcus aureus isolates, MICs of oxacillin were also tested by Etest to differentiate oxacillin-sensitive and oxacillin-resistant S. aureus. Results Ertapenem was highly active in vitro against many aerobic and facultative bacterial pathogens commonly recovered from patients with community-acquired bacteremia (128/159, 80.5 %. Ertapenem had more potent activity than ceftriaxone, piperacillin

  10. Antimicrobial susceptibility pattern of bacterial isolates from wound infection and their sensitivity to antibiotic agents at super specialty hospital, Amravati city, India

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    Hrishikesh Sawdekar

    2015-02-01

    Full Text Available Background: Wound infection is one of the health problems that is caused and aggravated by the invasion of pathogenic organisms. Information on local pathogens and sensitivity to antimicrobial agent is crucial for successful treatment of wounds. So the present study was conducted to determine antimicrobial susceptibility pattern of bacterial isolates from wound infection and their sensitivity to antimicrobial agents. Methods: A retrospective study was conducted among patients with wound infection in Suyash super speciality hospital, from January 2012 to December 2013. Wound swab was collected using sterile cotton swabs and processed for bacterial isolation and susceptibility testing to Systemic antimicrobial agents. Results: In this study 78 bacterial isolates were recovered from 258 specimens showing an isolation rate of 31.2%. The predominant bacteria isolated from wounds were gram positive staphylococci 36 (46.2%, followed by gram negative streptococci 18 (23.1% gram negative pseudomonas 12 (15.4 % and gram negative proteus 8 (10.4%. The gram positive and gram negative bacteria constituted 68 (87.2% and 10 (12.8% of bacterial isolates; respectively. Conclusion: In the present study most of the pathogens isolated from wound isolates showed high rate of resistance to most commonly used newer antibiotics used to treat bacterial infections. Therefore, rational use of antibiotics should be practiced. [Int J Res Med Sci 2015; 3(2.000: 433-439

  11. Microdilution procedure for antifungal susceptibility testing of Paracoccidioides brasiliensis to amphotericin b and itraconazole

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    E Takahagi-Nakaira

    2009-01-01

    Full Text Available In vitro tests employing microdilution to evaluate fungal susceptibility to antifungal drugs are already standardized for fermentative yeasts. However, studies on the susceptibility of dimorphic fungi such as Paracoccidioides brasiliensis employing this method are scarce. The present work introduced some modifications into antifungal susceptibility testing from the European Committee on Antimicrobial Susceptibility Testing (EUCAST, concerning broth medium and reading time, to determine minimal inhibitory concentration (MIC of amphotericin B and itraconazole against Paracoccidioides brasiliensis. Yeast-like cells of P. brasiliensis (Pb18 strain were tested for susceptibility to amphotericin B and itraconazole in RPMI 1640 medium, supplemented with 2% glucose and nitrogen source and incubated at 35°C. The MIC of amphotericin B and itraconazole against Pb18 were respectively 0.25 µg/mL and 0.002 µg/mL. The results of minimal fungicidal concentration (MFC showed that amphotericin B at 0.25 µg/mL or higher concentrations displayed fungicidal activity against Pb18 while itraconazole at least 0.002 µg/mL has a fungistatic effect on P. brasiliensis. In conclusion, our results showed that the method employed in the present study is reproducible and reliable for testing the susceptibility of P. brasiliensis to antifungal drugs.

  12. Identification and Antimicrobial Susceptibility of Salmonella species Isolated from Washing and Rinsed Water of Broilers in Pluck Shops

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    Tuhin-Al-Ferdous

    2013-02-01

    Full Text Available The study was designed with a view to isolate, identifies and characterizes Salmonella species from washing and rinsed water of broilers in pluck shops at Sreepur of Gazipur district in Bangladesh during the period from December 2011 to May 2012. A total of 30 samples collected from the different layers of drums of pluck shops’ were subjected to bacterial isolation and identification by using cultural and biochemical techniques. Furthermore, the isolated Salmonella species were characterized by antimicrobial susceptibility testing. Among the 27 positiveSalmonella isolates 11.11% (n = 3 were Salmonella pullorum, 29.83% isolates (n = 8 were Salmonella gallinarum and the rest 59.26% isolates (n = 16 were Salmonella typhimurium. In case of motility test performed by MIU media and hanging drop slide method, 40.74% isolates were non-motile and 59.26% isolates were motile. Salmonella spp. were resistant to doxycyclin and erythromycin. However, most of the Salmonella spp. were susceptible to sulfamethoxazole-trimethoprim and gentamicin. Out of 27 Salmonella isolates, 75% Salmonella typhimurium, 100% Salmonella gallinarum and 100% Salmonella pullorum were detected as multidrug resistant. The findings of the study revealed the presence of multidrug resistant Salmonella species in washing and rinsed water of broilers in Pluck shops at Sreepur of Gazipur district in Bangladesh.

  13. Susceptibility of bacterial etiological agents to commonly-used antimicrobial agents in children with sepsis at the Tamale Teaching Hospital

    OpenAIRE

    Acquah, Samuel EK; Quaye, Lawrence; Sagoe, Kenneth; Juventus B. Ziem; Bromberger, Patricia I; Amponsem, Anthony A

    2013-01-01

    Background Bloodstream infections in neonates and infants are life-threatening emergencies. Identification of the common bacteria causing such infections and their susceptibility patterns will provide necessary information for timely intervention. This study is aimed at determining the susceptibilities of bacterial etiological agents to commonly-used antimicrobial agents for empirical treatment of suspected bacterial septicaemia in children. Methods This is a hospital based retrospective anal...

  14. Reduced Susceptibility to Rifampicin and Resistance to Multiple Antimicrobial Agents among Brucella abortus Isolates from Cattle in Brazil

    OpenAIRE

    Barbosa Pauletti, Rebeca; Reinato Stynen, Ana Paula; Pinto da Silva Mol, Juliana; Seles Dorneles, Elaine Maria; Alves, Telma Maria; de Sousa Moura Souto, Monalisa; Minharro, Silvia; Heinemann, Marcos Bryan; Lage, Andrey Pereira

    2015-01-01

    This study aimed to determine the susceptibility profile of Brazilian Brucella abortus isolates from cattle to eight antimicrobial agents that are recommended for the treatment of human brucellosis and to correlate the susceptibility patterns with origin, biotype and MLVA16-genotype of the strains. Screening of 147 B. abortus strains showed 100% sensitivity to doxycycline and ofloxacin, one (0.68%) strain resistant to ciprofloxacin, two strains (1.36%) resistant to streptomycin, two strains (...

  15. Treatment of enteric fever in children on the basis of current trends of antimicrobial susceptibility of Salmonella enterica serovar typhi and paratyphi A

    Directory of Open Access Journals (Sweden)

    Manchanda V

    2006-01-01

    Full Text Available Purpose: Recent reports indicate decreased susceptibility of S. typhi to fluoroquinolones, especially ciprofloxacin. Chloramphenicol has been suggested as first line therapy of enteric fever in many studies. This is a prospective study that describes the trends of antimicrobial susceptibility of S. typhi and S. paratyphi A causing bacteraemia in children and reports therapeutic failure to ciprofloxacin and evaluates the possible use of chloramphenicol, ampicillin, ciprofloxacin and third generation cephalosporins as first line therapy in the treatment of enteric fever in children. Methods: The present study was conducted from April 2004 to March 2005 in a superspeciality children hospital at New Delhi. A total of 56 S. typhi and five S. paratyphi A isolates were obtained among the 673 blood cultures performed. Antimicrobial testing was done using disk diffusion technique (NCCLS method for 13 antimicrobials and MICs were calculated for ampicillin, ciprofloxacin, chloramphenicol and cefotaxime. Analysis of data was done using WHONET software. Results: All 56 isolates of S. typhi were sensitive to amoxycillin+clavulanate, gentamicin, cefixime, cefotaxime and ceftazidime. Multidrug resistance (MDR, resistance to three drugs was seen in 22 cases (39% and resistance to five drugs was seen in 12 cases (21%. Only two isolates were resistant to chloramphenicol (3%. MIC 90 for ampicillin, chloramphenicol, ciprofloxacin and cefotaxime were 1.0 mg/ml, 4.0 mg/ml, 64 mg/ml and 0.125 mg/ml respectively. All S. paratyphi A isolates were sensitive to ampicillin and chloramphenicol and resistant to nalidixic acid.MIC distribution data for chloramphenicol revealed elevated MIC but still in susceptible range. Conclusions: There is an urgent need for further clinical studies to evaluate response to chloramphenicol in such cases. Antimicrobial susceptibility data and MIC distribution favour use of ampicillin as a drug of choice for the treatment of enteric fever

  16. Etiology, antimicrobial susceptibility profile of Staphylococcus spp. and risk factors associated with bovine mastitis in the states of Bahia and Pernambuco

    Directory of Open Access Journals (Sweden)

    Carina C. Krewer

    2013-05-01

    Full Text Available The purpose of this paper was to study the etiology of mastitis, determine the antimicrobial susceptibility profile of Staphylococcus spp. and to identify the risk factors associated with infection in dairy cows in the states of Bahia and Pernambuco, Brazil. From the 2,064 milk samples analyzed, 2.6% were associated with cases of clinical mastitis and 28.2% with subclinical mastitis. In the microbiological culture, Staphylococcus spp. (49.1% and Corynebacterium spp. (35.3% were the main agents found, followed by Prototheca spp. (4.6% and Gram negative bacilli (3.6%. In the antimicrobial susceptibility testing, all 218 Staphylococcus spp. were susceptible to rifampicin and the least effective drug was amoxicillin (32.6%. Multidrug resistance to three or more drugs was observed in 65.6% of Staphylococcus spp. The risk factors identified for mastitis were the extensive production system, not providing feed supplements, teat drying process, not disinfecting the teats before and after milking, and inadequate hygiene habits of the milking workers. The presence of multiresistant isolates in bovine milk demonstrates the importance of the choice and appropriate use of antimicrobial agents. Prophylactic and control measures, including teat antisepsis and best practices for achieving hygienic milking should be established in order to prevent new cases of the disease in herds.

  17. Spectrum and antimicrobial susceptibility pattern of pathogens causing urinary tract infection experience in a tertiary care setting

    International Nuclear Information System (INIS)

    Objective: To determine the spectrum and antimicrobial susceptibility pattern of pathogens causing urinary tract infection from the samples received at AFIP Rawalpindi. Place and duration of study. The study was carried out at Department of Microbiology, Armed Forces Institute of Pathology from January 2010 to June 2010. Material and Method: This was descriptive cross-sectional study. A total of 500 bacterial isolates out of 2050 urine culture samples, for a period of six month were included in the study. Indentification was carried out by standard biochemical profile of the organisms. The antimicrobial susceptibilities of isolated organisms were performed by disk diffusion method as recommended by Clinical Laboratory Standard Institute. Results Out of the culture positive cases, gram-negative bacteria constituted the largest group with a total of 434 (87%) isolates, while gram-positive bacteria constituted only 44 (8.8%) isolates. E. coli was the most common isolate accounting for 63% of the total positive bacterial cultures followed by Klebsiella spp (9%) and P. aernginosa (7%). Susceptibility pattern of E. coli revealed that 96% of isolates were sensitive to imipenem, 91% to piperacillin-tazobactam and 87% to Nitrofurantoin. For Klebsiella spp, 86% of Isolates were susceptible to Imipenem and 71 % to piperacillin-tazobactam. As regards acinetobacter spp, 94% of Isolates were susceptible to piperacillin-tazobactam and 70 % to Imipenem an piperacilline-sulbactam. Antibiogram of P. aeruginosa revealed that 94% of isolates were sensitive to ceftazidime and 86% to imipenem. Nitrofurantoin was the most effective urinary antibiotic in case of enterococcus spp as 85% of isolates were susceptible to this compound. Conclusion: From the present study we conclude that E. coli was the predominant urinary pathogen in our set up. The antimicrobial susceptibility patterns of E. coli revealed that majority of isolates were susceptible to imipenem and piperacilline

  18. Etiologic profile and antimicrobial susceptibility of community-acquired urinary tract infection in two Cameroonian towns

    OpenAIRE

    Akoachere Jane-Francis Tatah; Yvonne Suylika; Akum Njom; Seraphine Esemu

    2012-01-01

    Abstract Background Urinary tract infection (UTI) represents one of the most common diseases encountered in community medical practice. In resource poor settings, treatment is usually empiric due to the high cost and long duration required for reporting diagnosis by culture and antibiotic susceptibility testing. With the growing problem of drug resistance knowledge of antibiotic susceptibility pattern is pertinent for successful eradication of invading pathogens. Our study, the first of its k...

  19. Disk susceptibility testing of slow-growing anaerobic bacteria.

    Science.gov (United States)

    Kwok, Y Y; Tally, F P; Sutter, V L; Finegold, S M

    1975-01-01

    The susceptibility of 55 strains of slow-growing anaerobes to eight clinically useful or potentially useful antibiotics was determined by agar dilution and disk diffusion tests. Strains of the genera Peptococcus, Peptostreptococcus, Megasphaera, Veillonella, Eubacterium, Bifidobacterium, Clostridium, and Fusobacterium were included. All strains were susceptible to chloramphenicol, but varied in their susceptibility to penicillin, lincomycin, clindamycin, tetracyclines, and vancomycin. Correlation between minimal inhibitory concentration and inhibition zone diameters was generally good. Prediction of susceptibility based on zone diameter measurements appeared satisfactory. Although routine susceptibility testing of anaerobic bacteria is not recommended, there are circumstances where such testing is relevant to the clinical situation. For those laboratories ill-equipped to do dilution tests, a disk diffusion test would give relatively accurate preliminary information. Quantitative susceptibility tests could then be done by a reference laboratory. PMID:1137353

  20. Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    According to the instantaneous growth rate (dN/dt) of E. coli CVCC249 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase and declining phase, in each of which obvious variation in physiological and biochemical properties was detected, including total DNA, total protein, and MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N0/{1+exp[r((x-BC50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC50 represents the mean level of susceptivity, while the bactericidal span BC1-99=(2lnN0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC249 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase and declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity and research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

  1. [Susceptibility of clinically-isolated bacteria strains to respiratory quinolones and evaluation of antimicrobial agent efficacy by Monte Carlo simulation].

    Science.gov (United States)

    Kosaka, Tadashi; Yamada, Yukiji; Kimura, Takeshi; Kodama, Mai; Fujitomo, Yumiko; Masaki, Nakanishi; Toshiaki, Komori; Keisuke, Shikata; Fujita, Naohisa

    2016-02-01

    Respiratory quinolones (RQs) are broad-spectrum antimicrobial agents used for the treatment of a wide variety of community-acquired and nosocomial infections. However, bacterial resistance to quinolones has been on the increase. In this study, we investigated the predicted efficacy of RQs for various strains of 9 bacterial species clinically isolated at our university hospital using the Monte Carlo simulation (MCS) method based on pharmacokinetics/pharmacodynamics modeling. In addition, the influence of the patients' renal function on the efficacy of RQs was evaluated. We surveyed antimicrobial susceptibility testing of 9 bacterial species (n = number of strains) [Streptococcus pneumoniae (n = 15), Streptococcus pyogenes (n = 14), Streptococcus agalactiae (n = 19), methicillin-susceptible Staphylococcus aureus (MSSA) (n = 24), Escherichia coli (n = 35), Haemophilus influenzae (n = 17), Klebsiella pneumoniae (n = 14), Pseudomonas aeruginosa (n = 31), and Moraxella catarrhalis (n = 11)] to 4 RQs [garenoxacin (GRNX), levofloxacin (LVFX), sitafloxacin (STFX), and moxifloxacin (MFLX)]. We found that compared with the other RQs, Gram-positive cocci was most resistant to LVFX, and that the minimum inhibitory concentration (MIC₉₀) values for S. pneumoniae, S. pyogenes, S. agalactiae, and MSSA were high (2, 16, > 16, and 8 µg/mL, respectively). In regard to Gram-negative rods, the susceptibility of E. coli to RQs was found to be decreased, with the MIC₉₀ values of GRNX, LVFX, STFX, and MFLX being > 16, 16, 1, and 16 µg/mL, respectively. MCS revealed that the target attainment rate of the area under the unbound concentration-time curve divided by the MIC₉₀ (ƒ · AUC/MIC ratio), against S. pneumoniae was 86.9-100%, but against E. coli was low (52.1-66.2%). The ƒ · AUC/MIC target attainment rate of LVFX against S. pneumoniae, S. pyogenes, and S. agalactiae tended to decrease due to increased creatinine clearance, and that of LVFX and STFX against MSSA also

  2. Antimicrobial Susceptibilities, Phage Types, and Molecular Characterization of Salmonella enterica Serovar Enteritidis from Chickens and Chicken Meat in Turkey

    DEFF Research Database (Denmark)

    Kalender, H.; Sen, S.; Hasman, Henrik; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2009-01-01

    Thirty-eight Salmonella Enteritidis isolates from chickens and chicken meat in Turkey were examined for antimicrobial susceptibility, XbaI pulsed-field gel electrophoresis (PFGE) patterns, phage types, plasmid profiles, and resistance genes. Seven different PFGE patterns were observed, with the...

  3. Bacterial contamination, bacterial profile and antimicrobial susceptibility pattern of isolates from stethoscopes at Jimma University Specialized Hospital

    OpenAIRE

    Shiferaw, Teklu; Beyene, Getenet; Kassa, Tesfaye; Sewunet, Tsegaye

    2013-01-01

    Introduction Hospital acquired infections are recognized as critical public health problems. Infections are frequently caused by organisms residing in healthcare environment, including contaminated medical equipment like Stethoscopes. Objective To determine bacterial contamination, bacterial profile and anti-microbial susceptibility pattern of the isolates from stethoscopes at Jimma University Specialized Hospital. Methodology Cross-sectional study conducted from May to September 2011 at Jimm...

  4. Molecular epidemiology and antimicrobial susceptibility of clinical Staphylococcus aureus from healthcare institutions in Ghana

    DEFF Research Database (Denmark)

    Egyir, Beverly; Guardabassi, Luca; Sørum, Marit;

    2014-01-01

    The objective of this study was to determine the antimicrobial susceptibility patterns and clonal diversity of clinical Staphylococcus aureus isolates from Ghana. A total of 308 S. aureus isolates from six healthcare institutions located across Northern, Central and Southern Ghana were characteri...

  5. Multicenter Evaluation of the Mycobacteria Growth Indicator Tube for Testing Susceptibility of Mycobacterium tuberculosis to First-Line Drugs

    OpenAIRE

    Rüsch-Gerdes, Sabine; Domehl, Cornelia; Nardi, Giampietro; Gismondo, Maria Rita; Welscher, Hans-Martin; Pfyffer, Gaby E.

    1999-01-01

    In a multicenter study involving three reference centers for mycobacteria, the reliability of the Mycobacteria Growth Indicator Tube (MGIT) for rapid antimicrobial susceptibility testing (AST) of Mycobacterium tuberculosis was evaluated and compared to the radiometric method (BACTEC 460TB). Test cultures for which the results of the MGIT and BACTEC 460TB tests were discordant were checked by the conventional proportion method on solid medium. Four hundred forty-one isolates have been tested f...

  6. Aspirin increases susceptibility of Helicobacter pylori to metronidazole by augmenting endocellular concentrations of antimicrobials

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ping Zhang; Wei-Hong Wang; Yu Tian; Wen Gao; Jiang Li

    2009-01-01

    AIM: To investigate the mechanisms of aspirin increasing the susceptibility of Helicobacter pylori ( H pylori) to metronidazole. METHODS: H pylori reference strain 26 695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin (1 mmol/L). The rdxA gene of H pylori was amplified by PCR and sequenced. The permeability of H pylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-3H]-tetracycline. The outer membrane proteins (OMPs) of H pylori 26 695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins (hopA, hopB, hopC, hopD and hopE) and the putative RND efflux system (hefABC) of H pylori were analyzed using real-time quantitative PCR. RESULTS: The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin. The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and hefA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION: Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of H pylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.

  7. The detection and antimicrobial susceptibility profile of Shigella isolates from meat and swab samples at butchers' shops in Gondar town, Northwest Ethiopia.

    Science.gov (United States)

    Garedew, Legesse; Hagos, Zenabu; Zegeye, Bidir; Addis, Zelalem

    2016-01-01

    Food borne pathogens are major causes of deaths, illnesses and billions of dollars of expenses. The burden of food borne illness is worsened by the ever increasing rate of antimicrobial resistance microbes. Shigella, a bacterial pathogen associated with food, is reported to account for higher prevalence rates of food borne illness in different settings. A cross-sectional study was conducted from February 10 to June 30, 2013, at the butcher houses of Gondar town in the Northwest of Ethiopia to assess the prevalence and antimicrobial susceptibility pattern of Shigella. Cattle raw meat and swab samples from selected critical control points, including knives, chopping boards, and the hands and noses of butchers, were collected and analyzed. The identification of Shigella was carried out using colony characteristics, the Gram reaction, and biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. The overall hygienic status of the butcher shops was also assessed using a checklist. An observational analysis revealed that the sanitary condition of the butcher shops and their premises was poor. Of 306 samples screened, 10.5% were positive for Shigella. Approximately 7.4% of meat samples and 10.2% of swab samples were contaminated with Shigella. Out of the total Shigella isolates, 90.6%, 46.9%, 18.8% and 9.4% were resistant to ampicillin, amoxicillin, ceftriaxone and tetracycline, respectively. A multidrug resistance pattern was recorded in 27.8% of the isolates. In conclusion, the safety of meat sold at Gondar butchers houses was poor. The identified Shigella isolates showed high levels of drug resistance and multidrug resistance patterns for commonly used antimicrobials in veterinary and human medicine. Practicing wise use of antimicrobials and strict sanitary interventions at different critical control points is strongly recommended, in addition to further in-depth studies to prevent unprecedented consequences from

  8. Short communication: In vitro antimicrobial susceptibility of Mycoplasma bovis isolates identified in milk from dairy cattle in Belgium, Germany, and Italy.

    Science.gov (United States)

    Barberio, A; Flaminio, B; De Vliegher, S; Supré, K; Kromker, V; Garbarino, C; Arrigoni, N; Zanardi, G; Bertocchi, L; Gobbo, F; Catania, S; Moroni, P

    2016-08-01

    The objective of this study was to assess the in vitro antimicrobial susceptibility of 73 isolates of Mycoplasma bovis isolated from milk of dairy cattle herds of Belgium, Germany, and Italy. Minimal inhibitory concentration (MIC) values were determined by the microbroth dilution method for the following antimicrobials: erythromycin, spiramycin, tilmicosin, tylosin, lincomycin, enrofloxacin, doxycycline, oxytetracycline, florfenicol, and tiamulin. Macrolides, florfenicol, oxytetracycline, and enrofloxacin, were chosen because they represent antimicrobials families commonly used in several countries for treatment of M. bovis, and their MIC values in cattle population are reported in several studies, allowing a comparison with previous data. Doxycycline and tiamulin were selected to assess the susceptibility of M. bovis to new antimicrobials, because they are not registered in the European Union for the treatment of dairy cattle. Among the agents of the different antimicrobial classes, the macrolides showed the highest concentration to inhibit 90% of isolates (MIC90), all above the highest concentration tested: >8μg/mL for erythromycin, >16μg/mL for spiramycin, and >32μg/mL for tilmicosin and tylosin. Also the MIC90 of lincomycin was above the highest concentration tested (>32μg/mL), but the distribution of the MIC values was almost perfectly bimodal: 41 isolates had a MIC ≤0.5μg/mL and 30 isolates >32μg/mL. Oxytetracycline had a 2-fold higher concentration to inhibit 50% of isolates (2 vs. 0.5μg/mL) and 1-fold higher MIC90 (4 vs. 2μg/mL) than doxycycline. Enrofloxacin and florfenicol had both a MIC90 of 2μg/mL, whereas tiamulin had a MIC90 of 0.5μg/mL. Significant differences on the MIC values were found among the 3 countries for several antimicrobials: compared with Germany, Belgium and Italy showed significantly higher MIC for lincomycin, spiramycin, and tylosin, and lower for oxytetracycline and florfenicol. The Belgian isolates showed the lowest MIC

  9. Antimicrobial susceptibility patterns of clinical Escherichia coli isolates from dogs and cats in the United States: January 2008 through January 2013.

    Science.gov (United States)

    Thungrat, Kamoltip; Price, Stuart B; Carpenter, D Mark; Boothe, Dawn Merton

    2015-09-30

    Escherichia coli is among the most common bacterial pathogens in dogs and cats. The lack of a national monitoring program limits evidence-based empirical antimicrobial choices in the United States. This study describes antimicrobial susceptibility patterns for presumed clinical E. coli isolates from dogs (n=2392) or cats (n=780) collected from six geographic regions in the United States between May 2008 and January 2013. Minimum inhibitory concentrations (MIC) were determined for 17 drugs representing 6 drug classes. Urinary tract isolates were most common (71%). Population MIC distributions were generally bimodal with the second mode above the resistant breakpoint for all drugs except gentamicin, amikacin, and meropenem. The MIC90 exceeded the susceptible breakpoint for ampicillin, amoxicillin-clavulanic acid, cephalothin (surrogate drug for cephalexin), and doxycycline but was below the susceptible breakpoint for all others. None of isolates was susceptible or resistant to all drug tested; 46% were resistant to 1 or 2 antimicrobial categories, and 52% to more than three categories. The resistance percentages were as follows: doxycycline (100%), cephalothin (98%)>ampicillin (48%)>amoxicillin-clavulanic acid (40%)>ticarcillin-clavulanic acid (18%)>cefpodoxime (13%), cefotaxime (12%), cefoxitin (11%), cefazolin (11%), enrofloxacin (10%), chloramphenicol (9.6%)>ciprofloxacin (9.2%), ceftazidime (8.7%), trimethoprim-sulfamethoxazole (7.9%), gentamicin (7.9%)>meropenem (1.5%), amikacin (0.7%) (P<0.05). Resistance to ampicillin and amoxicillin-clavulanic acid was greatest in the South-Central region (P<0.05). E. coli resistance may preclude empirical treatment with doxycycline, cephalexin, ampicillin, or amoxicillin-clavulanic acid. Based on susceptibility patterns, trimethoprim-sulfonamides may be the preferred empirical oral treatment. PMID:26165272

  10. Relative efficacy of cefuroxime versus dicloxacillin as definitive antimicrobial therapy in methicillin-susceptible Staphylococcus aureus bacteraemia

    DEFF Research Database (Denmark)

    Rasmussen, Jon Bjarke; Knudsen, Jenny Dahl; Arpi, Magnus;

    2014-01-01

    OBJECTIVES: The objective of the present study was to compare the efficacy of cefuroxime with that of dicloxacillin as definitive antimicrobial therapy in methicillin-susceptible Staphylococcus aureus bacteraemia (MS-SAB) using a Danish bacteraemia database, information on the indication for...... antimicrobial therapy, multivariate adjustment and propensity score (PS) matching. METHODS: This was a retrospective cohort study. MS-SAB cases from 1 January 2006 to 31 December 2008 were included from a total of seven hospitals in the greater Copenhagen area and seven hospitals in the North Denmark Region....... Information including demographics, antimicrobial therapy and clinical condition was obtained. The physician's note detailing the indication for starting empirical antimicrobial therapy was given special attention. Hazard ratios (HRs) and 95% CIs for 30 day and 90 day mortality were calculated using PS...

  11. Distribution and antimicrobial susceptibility of bacteria from adults with community-acquired pneumonia or complicated skin and soft tissue infections in France: the nationwide French PREMIUM study.

    Science.gov (United States)

    Leprince, C; Desroches, M; Emirian, A; Coutureau, C; Anais, L; Fihman, V; Soussy, C J; Decousser, J W

    2015-10-01

    The empirical therapy of community-acquired pneumonia (CAP) and complicated skin and soft tissue infections (cSSTIs) must be based on updated bacterial distribution and susceptibility data. A nationwide study consecutively collected 1288 isolates from CAP (n=467) and cSSTIs (n=821) from 18 French hospitals between 2012 and 2013. The MIC values of commonly used antimicrobial agents, including ceftaroline, were determined. Bacterial distribution featured Pneumococcus, Haemophilus influenzae, and Staphylococcus aureus for CAPs and S. aureus, β-hemolytic streptococci and Enterobacteriaceae for cSSTIs. Antimicrobial susceptibility testing indicated i) the sustained third-generation cephalosporins and levofloxacin activity against pneumococci and H. influenzae, ii) no methicillin-resistant Staphylococcus aureus emergence among respiratory pathogens, iii) the high in vitro activity of ceftaroline against staphylococci from cSSTIs (98.7% susceptibility), and iv) the worrisome decreasing fluoroquinolone and third-generation cephalosporin susceptibilities among Enterobacteriaceae. This laboratory-based survey depicts a contrasting situation and supports the scoring of patients for the resistant pathogen risk before empirical therapy. PMID:26166208

  12. In vitro antimicrobial susceptibility of Mycoplasma mycoides mycoides large colony and Arcanobacterium pyogenes isolated from clinical cases of ulcerative balanitis and vulvitis in Dorper sheep in South Africa

    Directory of Open Access Journals (Sweden)

    A. Kidanemariam

    2005-06-01

    Full Text Available The in vitro activities of enrofloxacin, florfenicol, oxytetracycline and spiramycin were determined against field isolates of Mycoplasma mycoides mycoides large colony (MmmLC by means of the broth microdilution technique. The minimum inhibitory concentrations (MICs of these antimicrobial drugs were determined for a representative number of 10 isolates and 1 type strain. The susceptibility of Arcanobacterium pyogenes to enrofloxacin, oxytetracycline and tilmicosin was determined by means of an agar disk diffusion test. The MICs of enrofloxacin, florfenicol, oxytetracycline and spiramycin were within the ranges of 0.125-0.5, 1.0-2.0, 2.0-4.0 and 4.0-8.0 µg / m , respectively. This study has shown that resistance of MmmLC against enrofloxacin, florfenicol, oxytetracycline and spiramycin was negligible. All the field strains of A. pyogenes that were tested were susceptible to enrofloxacin, oxytetracycline and tilmicosin with mean inhibition zones of 30.6, 42.3 and 35.8mm, respectively. Although there is lack of data on in vivo efficacy and in vitro MIC or inhibition zone diameter breakpoints of these antimicrobial drugs for MmmLC, the MIC results indicate that these 4 classes of antimicrobial drugs should be effective in the treatment of ulcerative balanitis and vulvitis in sheep in South Africa.

  13. Study of Prevalence and Antimicrobial Susceptibility of Blood Culture Bacterial Isolates

    Directory of Open Access Journals (Sweden)

    Ayobola, E. D.

    2011-01-01

    Full Text Available Bloodstream infections are associated with significant morbidity and mortality. Definitive diagnosis is by bacteriologic culture of blood samples to identify organisms and establish antibiotic susceptibility. Between July and September 2009, 249 blood samples collected from patients at the University of Benin Teaching Hospital were processed. Positive cultures which accounted for 48(19.3% of total samples screened, were purified and identified according to standard methods. Sensitivity of bacteria to different antibiotics was determined by Kirby-Bauer disk diffusion method. Microorganisms recovered were Staphylococcus aureus (14.6%, Providencia spp., Pseudomonas aeruginosa, Enterobacter spp., Klebsiella pneumoniae and Proteus mirabilis (12.5% respectively, Escherichia coli and Staphylococcus epidermidis (8.3% respectively and Citrobacter freundii (6.3% . The highest antibiotic activities against Gram positive isolates were observed for ofloxacin (90.9%, nitrofurantoin (81.8% and gentamicin (72.7%, while in Gram negative bacteria, ofloxacin (81.1% and nalidixic acid (45.9% were most effective. The possibility of drug resistance acquisition by bacteria makes continuous surveillance of antimicrobial susceptibility patterns of bacteria essential as this will enhance efforts to identify resistance and attempt to limit its spread.

  14. Antimicrobial susceptibilities and molecular epidemiology of clinical isolates of Clostridium difficile in taiwan.

    Science.gov (United States)

    Lin, Yi-Chun; Huang, Yu-Tsung; Tsai, Pei-Jane; Lee, Tai-Fen; Lee, Nan-Yao; Liao, Chun-Hsing; Lin, Shyr-Yi; Ko, Wen-Chien; Hsueh, Po-Ren

    2011-04-01

    The antimicrobial susceptibility and virulence factors of Clostridium difficile clinical isolates in Taiwan have not previously been reported. One hundred and thirteen isolates were collected from two major teaching hospitals in Taiwan from 2001 to 2009. Molecular typing was performed by an automated repetitive extragenic palindromic sequence-based PCR (rep-PCR) method (DiversiLab; Bacterial Barcodes, Inc., Athens, GA) and PCR ribotyping. Detection of tcdA, tcdB, cdtA, and cdtB genes was performed using a multiplex PCR assay, and gyrA and gyrB genes of moxifloxacin-nonsusceptible isolates were sequenced. All isolates were susceptible to vancomycin and metronidazole. Ninety-five (84%) isolates were susceptible to moxifloxacin, and the MIC(90) for nemonoxacin was 4 μg/ml. Tigecycline showed favorable antibacterial activity (MIC(90) of 0.06 μg/ml). Thirteen rep-PCR types were identified as a predominant rep-PCR type (type A; non-North American pulsed-field gel electrophoresis type 1 [NAP1], -NAP7, or -NAP8) accounting for 52.2% (59 isolates). Nine of 18 moxifloxacin-nonsusceptible isolates belonged to the rep-PCR type A. The rep-PCR type A and C isolates were distinct from NAP1 (ribotype 027) and NAP8 (ribotype 078) as determined by PCR ribotyping. Seventy-four (65%) isolates harbored tcdA and tcdB, and 15 (13%) harbored cdtAB encoding binary toxin. Eleven isolates had a gene deletion in tcdC, including a 39-bp deletion (9 isolates) and an 18-bp deletion (2). In conclusion, dissemination of a predominant C. difficile clone in southern and northern Taiwan was noted. However, no NAP1 (ribotype 027) isolate could be discovered in this study. PMID:21263053

  15. Susceptibility of Clostridium difficile Toward Antimicrobial Agents Used as Feed Additives for Food Animals

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Tvede, Michael

    2011-01-01

    A total of 65 toxigenic Clostridium difficile strains isolated from patients with antibiotic-associated diarrhea were tested for susceptibility to avilamycin, flavomycin, monensin, and salinomycin. Except for flavomycin the substances showed in vitro efficacy comparable to reports of the currently...

  16. Susceptibility testing of Propionibacterium acnes comparing agar dilution with E test.

    OpenAIRE

    Smith, M.A.; Alperstein, P; France, K.; Vellozzi, E M; Isenberg, H D

    1996-01-01

    Propionibacterium acnes has been identified as a significant agent of nosocomial infections, including endophthalmitis. Data concerning susceptibility of P. acnes to newer beta-lactam antibiotics and fluoroquinolones are limited. Recent reports suggest that quinolones have activity against these organisms sufficient to warrant further study. We undertook a study to select appropriate antimicrobial agents for use in a rabbit model of P. acnes endophthalmitis. We compared the antibiotic suscept...

  17. Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria.

    Science.gov (United States)

    Ayepola, Olayemi O; Olasupo, Nurudeen A; Egwari, Louis O; Becker, Karsten; Schaumburg, Frieder

    2015-01-01

    Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun States, Nigeria from 2010-2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC) were deduced using the Based Upon Repeat Pattern algorithm (BURP). Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL) was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test). Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%), t2304 (4.4%) and t8435 (4.1%). spa-CC 084 was predominant among isolates from infection (80.3%, n = 167) and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9-13.2, p<0.001, chi2-test). In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084. PMID:26348037

  18. Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria.

    Directory of Open Access Journals (Sweden)

    Olayemi O Ayepola

    Full Text Available Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217 and asymptomatic carriers (n = 73 during a cross sectional study in Lagos and Ogun States, Nigeria from 2010-2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC were deduced using the Based Upon Repeat Pattern algorithm (BURP. Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test. Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%, t2304 (4.4% and t8435 (4.1%. spa-CC 084 was predominant among isolates from infection (80.3%, n = 167 and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9-13.2, p<0.001, chi2-test. In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084.

  19. OCIMUM BASILICUM AND MENTHA PIPERITA ESSENTIAL OILS INFLUENCE THE ANTIMICROBIAL SUSCEPTIBILITY OF STAPHYLOCOCCUS AUREUS STRAINS

    Directory of Open Access Journals (Sweden)

    Dan Mihaiescu

    2012-03-01

    Full Text Available Essential oils extracted by microwave assisted hydrodistillation technique from Ocinum basilicum and Mentha piperita were characterized by GC-MS. An adapted diffusion method was used in order to assess the potentiator effect of the essential oils on the susceptibility of Staphylococcus aureus clinical and reference strains to some of the currently used antibiotics, i.e. clindamycin, ciprofloxacin, tetracycline, gentamicin, penicillin and erythromycin.. The Ocimum basilicum and Mentha piperita essential oils, exhibited a strong, strain specific influence on the antibiotic susceptibility of the tested strains.

  20. Antimicrobial susceptibility monitoring of mastitis pathogens isolated from acute cases of clinical mastitis in dairy cows across Europe: VetPath results.

    Science.gov (United States)

    Thomas, Valérie; de Jong, Anno; Moyaert, Hilde; Simjee, Shabbir; El Garch, Farid; Morrissey, Ian; Marion, Hervé; Vallé, Michel

    2015-07-01

    VetPath is an ongoing pan-European antimicrobial susceptibility monitoring programme collecting pathogens from diseased cattle, pigs and poultry not recently treated with antibiotics. Non-replicate milk samples were collected from cows with acute clinical mastitis in eight countries. Escherichia coli, Staphylococcus aureus and Streptococcus uberis were isolated by standardised methods. Antimicrobial susceptibility was determined in a central laboratory by CLSI broth microdilution methodology; results were interpreted using clinical breakpoints where available. Among E. coli (n=280), resistance to tetracycline (14.3%) and cefapirin (11.1%) were most common. Resistance to other β-lactam antibiotics was absent (ceftiofur) or very low (cefalexin, amoxicillin/clavulanic acid). The MIC90 of enrofloxacin and marbofloxacin was 0.03 and 0.06μg/mL, respectively, with 0.7% of strains displaying a deviating high MIC. Staphylococcus aureus (n=250) were susceptible to most antibiotics tested, although 36.0% were resistant to penicillin G. For other β-lactam antibiotics where a CLSI breakpoint was available, no resistance was detected. Tetracycline resistance was low (5.2%). Streptococcus uberis (n=282) were susceptible to all β-lactam antibiotics, although 29.8% were intermediately susceptible to penicillin G; 18.8% of strains were resistant to erythromycin and 28.7% to tetracycline. This European study shows that bacteria associated with acute clinical mastitis are susceptible to most antibiotics with the exception of penicillin G against S. aureus, and erythromycin and tetracycline against S. uberis. The results of this study should serve as a reference baseline. This work also highlights the urgent need to set additional clinical breakpoints for antibiotics frequently used to treat mastitis. PMID:26003836

  1. Reliability of provocative tests of motion sickness susceptibility

    Science.gov (United States)

    Calkins, D. S.; Reschke, M. F.; Kennedy, R. S.; Dunlop, W. P.

    1987-01-01

    Test-retest reliability values were derived from motion sickness susceptibility scores obtained from two successive exposures to each of three tests: (1) Coriolis sickness sensitivity test; (2) staircase velocity movement test; and (3) parabolic flight static chair test. The reliability of the three tests ranged from 0.70 to 0.88. Normalizing values from predictors with skewed distributions improved the reliability.

  2. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand.

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  3. Use of Aeromonas spp. as General Indicators of Antimicrobial Susceptibility among Bacteria in Aquatic Environments in Thailand

    Science.gov (United States)

    Usui, Masaru; Tagaki, Chie; Fukuda, Akira; Okubo, Torahiko; Boonla, Chanchai; Suzuki, Satoru; Seki, Kanako; Takada, Hideshige; Tamura, Yutaka

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria, and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya River, 2 sites at the mouth of Chao Phraya River, 3 sites in Ta Chin River, and 5 sites at city canals) and 12 sites (6 sites at city canals; 2 sites at chicken farms; 2 sites at pig farms; and 2 samples from sites at pig farms, which were subsequently treated at a biogas plant) in Thailand in 2013 and 2014, respectively. In total, 117 Aeromonas spp. were isolated from the water samples, and these organisms exhibited various antimicrobial susceptibility profiles. Notably, there was a significant correlation between the environmental concentration of tetracyclines and the rates of tetracycline resistance in the isolated Aeromonas spp.; however, both the concentration and rates of tetracycline resistance in samples derived from pig farms were higher than those of samples harvested from other aquatic environments. These findings suggest that the high concentrations of antimicrobials observed in these aquatic environments likely select for ARGs. Furthermore, they indicate that Aeromonas spp. comprise an effective marker for monitoring antimicrobial resistance in aquatic environments. PMID:27433156

  4. Antimicrobial susceptibility of canine and human Staphylococcus aureus collected in Saskatoon, Canada.

    Science.gov (United States)

    Rubin, J E; Chirino-Trejo, M

    2011-11-01

    Staphylococcus aureus is one of the most common causes of infection in people and is increasingly recognized in dogs. The increasing prevalence of methicillin resistant S. aureus (MRSA) is complicating the treatment of these infections. Panton Valentine leukocidin (PVL), a toxin involved in the pathogenesis of necrotic syndromes in people may be partially responsible for the rise of MRSA. Canine and human S. aureus from the same geographic area are genetically similar, indicating a common population and likely transmission. The implications of increasing antimicrobial resistance complicated by interspecies transmission, necessitates including both dogs and humans in S. aureus resistance surveillance studies. A collection of 126 S. aureus isolates from people (n = 99) and dogs (n = 27) were included, minimum inhibitor concentrations to a panel of 33 antimicrobials used in human and veterinary medicine were determined. No resistance to vancomycin, linezolid, daptomycin, quinupristin/dalfopristin or nitrofurantoin was found. A wide range of antibiograms were found; including resistance to 0-12 drugs (0-6 drug classes). Outstanding antibiograms included a canine MRSA resistant to rifampin and a human MRSA resistant to chloramphenicol. Inducible clindamycin resistance was found among 78% and 4% of canine and human MRSA and 17% and 25% of canine colonizing and human methicillin susceptible S. aureus (MSSA), respectively. Resistance to mupirocin was only found among human isolates including 20% of MRSA and 4% of MSSA. While no canine isolates were PVL positive, 39% of human MRSA and 2% of MSSA carried the gene. The bidirectional transmission of S. aureus between people and dogs necessitates the inclusion of isolates from both species in future studies. PMID:21824346

  5. Genomic characterization and antimicrobial susceptibility of bovine intrauterineEscherichia coli and its relationship with postpartum uterine infections

    Institute of Scientific and Technical Information of China (English)

    YANG Li-ming; WANG Yi-hao; PENG Yu; MIN Jiang-tao; HANG Su-qin; ZHU Wei-yun

    2016-01-01

    To investigate the roles ofEscherichia coli in the pathogenesis of postpartum uterine diseases in dairy cows, a total of 145E. coli isolates were recovered from 18 healthy cows (61 isolates) and 25 cows with clinical endometritis (84 isolates) at 25–35 days after parturition. Genomic characteristics including phylogenetic grouping, genetic diversity and virulence genes of E. coli isolates were screened to proifle the characteristics related to uterine infections. The susceptibility of the bacteria against 23 antibiotics was also evaluated to support prevention and treatment of clinical cases. Genetic diversity ofE. coli identiifed by random ampliifcation of polymorphic DNA (RAPD) revealed 103 clonal types, including 3 common types to unaffected cows and endometritis cows, 39 types speciifc to healthy cows and 61 types in endometritis subjects. In addition, the isolates from endometritis uteri showed more genetic variability compared with that of healthy cows. Ac-cording to the ifndings of phylogenetic grouping, theE. coli isolates were assigned to group A (35.9%), B1 (59.3%) and D (4.8%). The expression of 10 of 20 virulence gens were detected positively, and onlyifmH gene was revealed signiifcantly (P<0.05) associated with endometritis. From antimicrobial susceptibility test,E. coli was found highly resistant to tetracy-cline, ampicilin, carbenicilin and amoxicilin, but sensitive to amikacin, netilmicin, tobramycin, cefepime and ceftazidime. In conclusion,E. coliwere extensively observed in both healthy and endometritis cows, and presented a large clonal types, however, ifmH was the only gene observed associated with clinical endometritis. Our results suggest that the drugs like amikacin, netilmicin, tobramycin and cefepime could be considered for preventing and treating clinical endometritis in the practical management of dairy cow.

  6. Avaliação das metodologias M.I.C.E.®, Etest® e microdiluição em caldo para determinação da CIM em isolados clínicos Evaluation of M.I.C.E.TM, Etest® and CLSI broth microdilution methods for antimicrobial susceptibility testing of nosocomial bacterial isolates

    Directory of Open Access Journals (Sweden)

    Eloiza Helena Campana

    2011-04-01

    .I.C.E., Thermo Fisher Scientific, Basingstoke, UK, recently released into the market, represents a rapid alternative to antimicrobial susceptibility testing. OBJECTIVE: The objective of this study was to evaluate the performance of M.I.C.E. methodology in relation to broth microdilution (reference test and Etest® (BioMérieux, Marcy l'Étoile, France. Material and method: A total of 160 bacterial isolates were collected comprising the following species: P. aeruginosa (20, Acinetobacter spp. (20, K. pneumoniae (20, E. coli (20, S. aureus (20, coagulase-negative Staphylococcus (20, E. faecalis (20 and E. faecium (20. Following Clinical Laboratory Standands Institute (CLSI standards (2009 and the manufacturers' recommendations, antimicrobial susceptibility testing was performed using broth microdilution method, Etest and M.I.C.E. The results were interpreted according to the criteria established by CLSI and compared through regression analysis. RESULTS: All antimicrobial combinations vs. bacterial species were evaluated and M.I.C.E. methodology yielded good results with general correlation (MIC variation ± 1-log2 > 90%, except for cefotaxime (85% and vancomycin (76.3% when compared with the reference method. The M.I.C.E. results compared to Etest showed general correlation (> 96%, except for amoxicillin/clavulanic acid (67.5% combination. CONCLUSION: AST results obtained from M.I.C.E. methodology showed a good correlation with those from broth microdilution and Etest, which corroborates its time effectiveness in the determination of MIC. However, the combination of amoxicillin/clavulanic acid requires further attention.

  7. Multiplex PCR to determine Streptococcus pneumoniae serotypes causing otitis media in the Republic of Ireland with further characterisation of antimicrobial susceptibilities and genotypes.

    LENUS (Irish Health Repository)

    Vickers, I

    2011-03-01

    The purpose of this study was to determine the serotypes, genotypes and antimicrobial susceptibilities of Streptococcus pneumoniae causing otitis media (OM) in children in Dublin, Ireland. S. pneumoniae isolates (n = 28) from spontaneously discharging OM were studied. Serotyping was performed using a previously undescribed multiplex polymerase chain reaction (PCR) scheme in combination with serological methods. Multilocus sequence typing (MLST) was performed using standard procedures. Antimicrobial susceptibility testing was performed using the Etest method. Fourteen different S. pneumoniae serotypes were identified. The five most common serotypes were 3, 19F, 19A, 14 and 6A, which accounted for 68% of all infections. The 7-valent pneumococcal conjugate vaccine (PCV7), 10-valent pneumococcal conjugate vaccine (PHiD-CV) and 13-valent pneumococcal conjugate vaccine (PCV13) provided potential coverages of 43%, 46% and 86%, respectively. Reduced susceptibility to penicillin was evident for 25% of isolates and was associated with serotypes 14, 19A, 19F and 9V. A total of 21 different sequence types (STs) were identified. Pneumococcal Molecular Epidemiology Network (PMEN) clones or their variants represented 54% (15\\/28) of all isolates. Continued monitoring and characterisation of S. pneumoniae causing OM in Ireland is warranted in order to guide future vaccine and treatment policies.

  8. Caspofungin Etest susceptibility testing of Candida species

    DEFF Research Database (Denmark)

    Arendrup, Maiken Cavling; Pfaller, Michael A; Rosenvinge, Flemming Schønning

    2012-01-01

    The purpose of this study was to evaluate the performance of caspofungin Etest and the recently revised CLSI breakpoints. A total of 497 blood isolates, of which 496 were wild-type isolates, were included. A total of 65/496 susceptible isolates (13.1%) were misclassified as intermediate (I) or re...... resistant (R). Such misclassifications were most commonly observed for Candida krusei (73.1%) and Candida glabrata (33.1%). The revised breakpoints cannot be safely adopted for these two species....

  9. Antimicrobial susceptibility of photodynamic therapy (UVA/riboflavin against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Renata Tiemi Kashiwabuchi

    2012-12-01

    Full Text Available PURPOSE: To assess S. aureus in vitro viability after the exposure to ultraviolet light A (UVA and riboflavin (B2. METHODS: Samples of S. aureus in 96 well plates (in triplicate were exposed to riboflavin (B2 and ultraviolet light A (365 nm wavelength at a power density of 3 mW/cm², 8 mm spot diameter, for 30 minutes. Control groups were prepared as well in triplicate: blank control, ultraviolet light A only, riboflavin only and dead bacteria Control. The bacterial viability was measured using fluorescent microscopy. In order to investigate the occurrence of "viable but non-culturable" microorganisms after treatment, the cell viability was also investigated by plate culture procedure onto a broth medium. Statistical analysis was performed using the triplicate values from each experimental condition. RESULTS: No difference was observed among the treatment group and the control samples (p=1. CONCLUSION: The combination of riboflavin 0.1% and ultraviolet light A at 365 nm did not exhibit antimicrobial activity against oxacillin susceptible S. aureus.

  10. Antimicrobial Susceptibility and Microorganisms Isolated from Blood Cultures of Hospitalized Patients in Intensive Care Units

    Directory of Open Access Journals (Sweden)

    Emine Küçükateş

    2016-06-01

    Full Text Available Aim: The aim of this study was to evaluate microorganism growth in blood cultures of hospitalized patients in our intensive care units and to determine appropriate antimicrobial agents for treatment. Methods: We retrospectively investigated the blood cultures obtained from the patients hospitalized in the Coronary and Surgical Intensive Care Units at the Institute of Cardiology, İstanbul University, between July 2013 and December 2014. All microorganisms were identified using the conventional methods. Results: A total of 1034 blood cultures were obtained from 324 patients. Microbial growth was detected in 174 (16.8% blood cultures of 68 patients. Among all microbial growth, 113 (58.55% were gram-positive bacteria, 69 (35.75% were gram-negative rods and 11 (5.7% were fungi. Staphylococcus aureus was the most frequent microorganism (48; 24.87%, followed by coagulasenegative Staphylococci (35; 18,13%, Enterococcus spp. (30; 15,54%, Stenotrophomonas maltophilia, Escherichia coli, and Pseudomonas spp. 60.4% of Staphylococcus aureus were methicillin-resistant and 65.7% of coagulase-negative Staphylococci were also methicillin-resistant. All Staphylococci and Enterococci were not resistant to vancomycin, teicoplanin and tigecycline. All the gram-negative rods were susceptible to colistin and tigecycline, followed by imipenem (71.6% and meropenem (70.7%. Conclusions: We assume that infection control measures must be increased due to high antibiotic resistance and besides, antibiotic policies should be improved.

  11. Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

    OpenAIRE

    Fernández-Natal, I.; J.A. Sáez-Nieto; Rodríguez-Lázaro, D.; Valdezate-Ramos, S.; Parras-Padilla, T.; Medina, M.J.; R.H. Rodríguez-Pollán; Van Der Blom, J; Tauch, A.; Soriano, F

    2016-01-01

    During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods u...

  12. Prevalence and Antimicrobial Susceptibility Patterns of Bacteria from Milkmen and Cows with Clinical Mastitis in and around Kampala, Uganda

    OpenAIRE

    Kateete, David Patrick; Kabugo, Usuf; Baluku, Hannington; Nyakarahuka, Luke; Kyobe, Samuel; Okee, Moses; Najjuka, Christine Florence; Joloba, Moses Lutaakome

    2013-01-01

    Background Identification of pathogens associated with bovine mastitis is helpful in treatment and management decisions. However, such data from sub-Saharan Africa is scarce. Here we describe the distribution and antimicrobial susceptibility patterns of bacteria from cows with clinical mastitis in Kampala, Uganda. Due to high concern of zoonotic infections, isolates from milkmen are also described. Methodology/Principal Findings Ninety seven milk samples from cows with clinical mastitis and 3...

  13. Altered Competitive Fitness, Antimicrobial Susceptibility, and Cellular Morphology in a Triclosan-Induced Small-Colony Variant of Staphylococcus aureus

    OpenAIRE

    Forbes, Sarah; Latimer, Joe; Bazaid, Abdulrahman; McBain, Andrew J.

    2015-01-01

    Staphylococcus aureus can produce small-colony variants (SCVs) that express various phenotypes. While their significance is unclear, SCV propagation may be influenced by relative fitness, antimicrobial susceptibility, and the underlying mechanism. We have investigated triclosan-induced generation of SCVs in six S. aureus strains, including methicillin-resistant S. aureus (MRSA). Parent strains (P0) were repeatedly passaged on concentration gradients of triclosan using a solid-state exposure s...

  14. Interpretive criteria for mupirocin susceptibility testing of Staphylococcus spp. using CLSI guidelines.

    LENUS (Irish Health Repository)

    Creagh, S

    2012-02-03

    Mupirocin is an antimicrobial agent commonly used to treat staphylococcal infection or to eliminate persistent carriage. To date, interpretive criteria have not been established to define susceptibility or resistance when performing mupirocin susceptibility testing. In this evaluation, using CLSI guidelines, a total of 502 staphylococci comprising 219 methicillin-sensitive Staphylococcus aureus, 222 methicillin-resistant S. aureus and 61 coagulase-negative staphylococci are tested by broth microdilution, disc diffusion and E-test. Disc diffusion using 5 microg mupirocin discs was found to be a reliable method to distinguish susceptible and resistant strains. Minimum inhibitory concentration (MIC) determination was required to differentiate low-level and high-level resistance to mupirocin. E-test was found to be an accurate alternative to broth microdilution for the routine determination of MIC values of staphylococci to mupirocin. Broth microdilution and disc-diffusion results were plotted on a scattergram, and error rates were calculated. No errors were found using susceptibility criteria of < 4 microg\\/mL (MIC) and > 19 mm (zone diameter).

  15. Evaluation of the pathogenic potential, antimicrobial susceptibility, and genomic relations of Yersinia enterocolitica strains from food and human origin.

    Science.gov (United States)

    Lucero-Estrada, Cecilia S M; Soria, José Miguel; Favier, Gabriela Isabel; Escudero, María Esther

    2015-11-01

    Yersinia enterocolitica is a food-borne pathogen that causes gastroenteritis with occasional postinfection sequels. This study was aimed to determinate the pathogenic potential, antimicrobial susceptibility, and genomic relationships of Y. enterocolitica strains of different bioserotypes (B/O) isolated from foods and human samples in San Luis, Argentina. Strains obtained by culture were bioserotyped and characterized by phenotypic and genotypic virulence markers, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE). Yersinia enterocolitica was detected in 9.2% of 380 samples, with a distribution of 10.6% (30/284) for food products and 5.2% (5/96) for human samples. Regarding the pathogenic potential, B1A strains of different serotypes were virF(-) ail(-), of which 72.0% (13/18) were ystB(+) with virulence-related phenotypic characteristics. Among B2/O:9 isolates, 75.0% (9/12) exhibited the genotype virF(+) ail(+) ystB(-) along with phenotypic traits associated with virulence; the same genotype was observed in 80.0% (4/5) of B3/O:3 and B3/O:5 strains. By PFGE, it was possible to separate Y. enterocolitica biotypes into 4 clonal groups (A to D) with 23 genomic types, generating a discriminatory index of 0.96. All isolates were susceptible to antimicrobials used for clinical treatment. This study highlights the presence of pathogenic bioserotypes and the high genomic diversity of the Y. enterocolitica strains isolated in our region. PMID:26370735

  16. Environmental parameters and antimicrobial susceptibility of enterobacteriaceae isolated from estuarine waters of São Vicente, São Paulo state, Brazil

    Directory of Open Access Journals (Sweden)

    N. G. G. S. Lourenço

    2007-01-01

    Full Text Available Diseases transmitted by water consists a serious public health problem and enterobacteria are the main group of microorganisms responsible for outbreaks in humans. Such pathogenic bacteria proliferate in water polluted by domestic and industrial sewage and reach the population through seawater contact. The aim of the present work was to study environmental parameters as well as to identify Enterobacteriaceae species and their antimicrobial susceptibility in water samples collected from the estuarine area of São Vicente city (São Paulo State, Brazil. Strains were identified by using traditional biochemical tests described in literature and antimicrobial susceptibility tests were carried out using the disk diffusion method. Out of 26 samples, Escherichia coli was the most frequent species (40.1%, followed by Citrobacter, Enterobacter and Klebsiella. The most effective drugs against the tested microorganisms were gentamycin, netilmicin, ciprofloxacin and cefepime. Since these bacteria are commonly found in seashore contaminated by sewage effluents, it can be concluded that estuarine waters of São Vicente are polluted and potentially capable of causing diseases and spreading pathogenic bacteria to human communities.

  17. Antimicrobial susceptibility monitoring of bacterial pathogens isolated from respiratory tract infections in dogs and cats across Europe: ComPath results.

    Science.gov (United States)

    Morrissey, Ian; Moyaert, Hilde; de Jong, Anno; El Garch, Farid; Klein, Ulrich; Ludwig, Carolin; Thiry, Julien; Youala, Myriam

    2016-08-15

    ComPath is a pan-European resistance monitoring programme collecting bacterial pathogens from dogs and cats. We present data for respiratory tract infection (RTI) isolates collected between 2008 and 2010. Antimicrobial minimal inhibitory concentrations (MICs) were determined and susceptibility calculated following Clinical Laboratory Standards Institute (CLSI) standards for veterinary medicine. The main pathogen from dogs was Staphylococcus intermedius Group (49/215, 22.8%) which was >90% susceptible to most antimicrobials (including oxacillin - 93.9%; 3 isolates confirmed mecA-positive) but only 59.2%, 73.5% and 87.8% susceptible to tetracycline, chloramphenicol and penicillin. Bordetella bronchiseptica (48/215, 22.3%), streptococci (36/215, 16.7%), Escherichia coli (24/215, 11.2%) and Pasteurella multocida (23/215, 10.7%) were also found in dog RTI. There are no breakpoints for Bordetella bronchiseptica. Most streptococci were penicillin- chloramphenicol-, ampicillin- and pradofloxacin-susceptible. None were enrofloxacin-resistant but 6 isolates (16.7%) were of intermediate susceptibility. The least active agent against streptococci was tetracycline (47.2% susceptible). For E. coli, 37.5% were ampicillin-susceptible but 83.3% were amoxicillin/clavulanic acid-susceptible. Only chloramphenicol showed susceptibility>90% against E. coli, with 66.7% tetracycline-susceptible and 79.2% to 87.5% susceptibility to enrofloxacin, trimethoprim-sulfamethoxazole or pradofloxacin. P. multocida were susceptible to pradofloxacin (no other breakpoints are available). The main pathogen from cats was P. multocida (82/186, 44.1%), where only pradofloxacin has breakpoints (100% susceptible). Streptococci were also collected from cats (25/186, 13.4%) and were >90% susceptible to all antimicrobials except tetracycline (36% susceptible). Most susceptibility was calculated with human-derived breakpoints and some antimicrobials had no breakpoints. Therefore predictions of clinical utility

  18. Distribution, Detection of Enterotoxigenic Strains and Antimicrobial Drug Susceptibility Patterns of Bacteroides Fragilis Group in Diarrheic and Non-Diarrheic Feces from Brazilian Infants

    OpenAIRE

    Débora Paula Ferreira; Vânia Lúcia Silva; Danielle Aparecida Guimarães; Cíntia Marques Coelho; Danielle Alves Gomes Zauli; Luiz de Macêdo Farias; Maria Auxiliadora Roque Carvalho; Claudio Galuppo Diniz

    2010-01-01

    Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrhe...

  19. Susceptibility of Staphylococcus aureus Clinical Isolates to Propolis Extract Alone or in Combination with Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Mieczysław Sajewicz

    2013-08-01

    Full Text Available The objective of this study was to assess in vitro the antimicrobial activity of ethanolic extract of Polish propolis (EEPP against methicillin-sensitive Staphylococcus aureus (MSSA and methicillin-resistant Staphylococcus aureus (MRSA clinical isolates. The combined effect of EEPP and 10 selected antistaphylococcal drugs on S. aureus clinical cultures was also investigated. EEPP composition was analyzed by a High Performance Liquid Chromatography (HPLC method. The flavonoid compounds identified in Polish Propolis included flavones, flavonones, flavonolols, flavonols and phenolic acids. EEPP displayed varying effectiveness against twelve S. aureus strains, with minimal inhibitory concentration (MIC within the range from 0.39 to 0.78 mg/mL, determined by broth microdilution method. The average MIC was 0.54 ± 0.22 mg/mL, while calculated MIC50 and MIC90 were 0.39 mg/mL and 0.78 mg/mL, respectively. The minimum bactericidal concentration (MBC of the EEPP ranged from 0.78 to 3.13 mg/mL. The in vitro combined effect of EEPP and 10 antibacterial drugs was investigated using disk diffusion method-based assay. Addition of EEPP to cefoxitin (FOX, clindamycin (DA, tetracycline (TE, tobramycin (TOB, linezolid (LIN, trimethoprim+sulfamethoxazole (SXT, penicillin (P, erythromycin (E regimen, yielded stronger, cumulative antimicrobial effect, against all tested S. aureus strains than EEPP and chemotherapeutics alone. In the case of ciprofloxacin (CIP and chloramphenicol (C no synergism with EEPP was observed.

  20. Are Creativity Tests Susceptible to Coaching?

    Science.gov (United States)

    Fairweather, Elizabeth C.; Cramond, Bonnie; Landis, Rebecca Nordin

    2015-01-01

    Critics of creativity tests, some of which are used widely in determining student eligibility for special educational opportunities such as gifted programs, claim that scores on these tests can be improved with specific training on the scoring components of the tests. However, we could find no empirical evidence supporting this claim. So, we…

  1. Antimicrobial activities of natural antimicrobial compounds against susceptible and antibiotic-resistant pathogens in the absence and presence of food

    Science.gov (United States)

    In an effort to improve microbial food safety, we are studying the antimicrobial activities of different classes of natural compounds including plant essential oils, apple, grape, olive, and tea extracts, bioactive components, and seashell-derived chitosans against multiple foodborne pathogens in cu...

  2. Determination of Susceptibilities of 26 Leptospira sp. Serovars to 24 Antimicrobial Agents by a Broth Microdilution Technique

    OpenAIRE

    Murray, Clinton K.; Hospenthal, Duane R.

    2004-01-01

    The MICs of 24 antimicrobials for 26 Leptospira spp. serovars were determined using a broth microdilution technique. The MICs at which 90% of isolates tested were inhibited (MIC90s) of cefepime, imipenem-cilastatin, erythromycin, clarithromycin, and telithromycin were all ≤0.01 μg/ml. The MIC90s of amoxicillin, aztreonam, cefdinir, chloramphenicol, and penicillin G were ≥3.13 μg/ml. Many antimicrobials have excellent in vitro activity against Leptospira.

  3. Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Sigrid Mayrhofer

    2011-01-01

    Full Text Available Strains of the genus Bifidobacterium are frequently used as probiotics, for which the absence of acquired antimicrobial resistance has become an important safety criterion. This clarifies the need for antibiotic susceptibility data for bifidobacteria. Based on a recently published standard for antimicrobial susceptibility testing of bifidobacteria with broth microdilution method, the range of susceptibility to selected antibiotics in 117 animal bifidobacterial strains was examined. Narrow unimodal MIC distributions either situated at the low-end (chloramphenicol, linezolid, and quinupristin/dalfopristin or high-end (kanamycin, neomycin concentration range could be detected. In contrast, the MIC distribution of trimethoprim was multimodal. Data derived from this study can be used as a basis for reviewing or verifying present microbiological breakpoints suggested by regulatory agencies to assess the safety of these micro-organisms intended for the use in probiotics.

  4. Antimicrobial susceptibility and beta-lactamase production of selected gram-negative bacilli from two Croatian hospitals: MYSTIC study results.

    Science.gov (United States)

    Bedenic, B; Goic-Barisic, I; Budimir, A; Tonkic, M; Mihajkevic, L J; Novak, A; Sviben, M; Plecko, V; Punda-Polic, V; Kalenic, S

    2010-06-01

    The meropenem yearly Susceptibility Test Information Collection (MYSTIC) programme is a global, longitudinal resistance surveillance network that monitors the activity of meropenem and compares its activity with other broadspectrum antimicrobial agents. We now report the antimicrobial efficacy of meropenem compared to other broad-spectrum agents within the selective Gram-negative pathogen groups from two Croatian Hospitals investigated between 2002-2007. A total of 1510 Gram-negative pathogens were tested and the minimum-inhibitory concentrations (MICs) were determined by broth microdilution method according to CLSI.There was no resistance to either imipenem or meropenem observed for Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis in both medical centers. High resistance rates of K. pneumoniae to ceftazidime (18%), cefepime (17%) and gentamicin (39%) are raising concern. Acinetobacter baumannii turned out to be the most resistant Gram-negative bacteria with 81% resistant to ceftazidime, 73% to cefepime, 69% to gentamicin and 71% to ciprofloxacin. Almost 20% of Pseudomonas aeruginosa strains were resistant to imipenem, 13% to meropenem, 69% to gentamicin and 38% to ciprofloxacin.The prevalence of extended-spectrum beta-lactamases (ESBLs) in E. coli was 10% and in K. pneumoniae 49%. PCR and sequencing of the amplicons revealed the presence of SHV-5 in nine E. coli strains and additional tem-1 beta-lactamase five strains. Five K. pneumoniae strains were positive for bla(SHV-5 )gene. Eight ESBL positive Enterobacter spp. strains were found to produce tem and CtX-m beta-lactamases. Plasmid-mediated AmpC beta-lactamases were not found among K. pneumoniae, E. coli and Enterobacter spp. Three A. baumannii strains from Zagreb University Center were identified by multiplex PCR as OXA-58 like producers. Six A. baumannii strains from Split University Center were found to possess an ISAba1 insertion sequence upstream of bla(OXA-51 )gene. According to our results

  5. Reduced Susceptibility to Rifampicin and Resistance to Multiple Antimicrobial Agents among Brucella abortus Isolates from Cattle in Brazil

    Science.gov (United States)

    Barbosa Pauletti, Rebeca; Reinato Stynen, Ana Paula; Pinto da Silva Mol, Juliana; Seles Dorneles, Elaine Maria; Alves, Telma Maria; de Sousa Moura Souto, Monalisa; Minharro, Silvia; Heinemann, Marcos Bryan; Lage, Andrey Pereira

    2015-01-01

    This study aimed to determine the susceptibility profile of Brazilian Brucella abortus isolates from cattle to eight antimicrobial agents that are recommended for the treatment of human brucellosis and to correlate the susceptibility patterns with origin, biotype and MLVA16-genotype of the strains. Screening of 147 B. abortus strains showed 100% sensitivity to doxycycline and ofloxacin, one (0.68%) strain resistant to ciprofloxacin, two strains (1.36%) resistant to streptomycin, two strains (1.36%) resistant to trimethoprim-sulfamethoxazole and five strains (3.40%) resistant to gentamicin. For rifampicin, three strains (2.04%) were resistant and 54 strains (36.73%) showed reduced sensitivity. Two strains were considered multidrug resistant. In conclusion, the majority of B. abortus strains isolated from cattle in Brazil were sensitive to the antimicrobials commonly used for the treatment of human brucellosis; however, a considerable proportion of strains showed reduced susceptibility to rifampicin and two strains were considered multidrug resistant. Moreover, there was no correlation among the drug susceptibility pattern, origin, biotype and MLVA16-genotypes of these strains. PMID:26181775

  6. Susceptibility testing of fish cell lines for virus isolation

    DEFF Research Database (Denmark)

    Ariel, Ellen; Skall, Helle Frank; Olesen, Niels Jørgen

    2009-01-01

    Passage of cell cultures may adversely influence cell susceptibility to virus infection through selection of cell clones that thrive in vitro but may not necessarily display high sensitivity to virus infection. Susceptibility to a given virus can therefore vary not only between cell lines and......-cell-culture-adapted" virus by propagating the virus in heterologous cell lines to the one tested. A stock of test virus was produced and stored at - 80 °C and tests were conducted biannually. This procedure becomes complicated when several cell lines are in use and does not account for variation among lineages. In comparing...... cell lineages, we increased the number of isolates of each virus, propagated stocks in a given cell line and tested all lineages of that line in use in the laboratory. Testing of relative cell line susceptibility between laboratories is carried out annually via the Inter-laboratory Proficiency Test...

  7. Sporulation properties and antimicrobial susceptibility in endemic and rare Clostridium difficile PCR ribotypes.

    Science.gov (United States)

    Zidaric, Valerija; Rupnik, Maja

    2016-06-01

    Increased sporulation and antibiotic resistance have been proposed to be associated with certain Clostridium difficile epidemic strains such as PCR ribotype 027. In this study we examined these properties in another widespread PCR ribotype, 014/020, in comparison to prevalent PCR ribotype 002 and a group of rarely represented PCR ribotypes. Highest sporulation was observed in 014/020 strains at 24 h, while after 72 h PCR ribotype 002 and rare PCR ribotypes formed higher total number of spores. PCR ribotype 014/020 strains exhibited slightly higher resistance to tested antimicrobials, followed by group of rare PCR ribotypes and less common PCR ribotype 002. Neither sporulation properties nor antibiotic resistance clearly differed in endemic and rare strains. PMID:27095618

  8. Antioxidant, Antimicrobial Activity and Toxicity Test of Pilea microphylla

    Directory of Open Access Journals (Sweden)

    Shaida Fariza Sulaiman

    2010-01-01

    Full Text Available A total of 9 plant extracts were tested, using two different kinds of extracting methods to evaluate the antioxidant and antimicrobial activities from Pilea microphylla (Urticaceae family and including toxicity test. Antioxidant activity were tested by using DPPH free radical scavenging, also total phenolic contents and total flavonoid contents were determined. Toxicity assay carried out by using brine shrimps. Methanol extract of method I (ME I showed the highest antioxidant activity at 69.51±1.03. Chloroform extract of method I (CE I showed the highest total phenolic contents at 72.10±0.71 and chloroform extract of method II (CE II showed the highest total flavonoid contents at 60.14±0.33. The antimicrobial activity of Pilea microphylla extract was tested in vitro by using disc diffusion method and minimum inhibitory concentration (MIC. The Pilea microphylla extract showed antibacterial activity against some Gram negative and positive bacteria. The extracts did not exhibit antifungal and antiyeast activity. The hexane extract of method I (HE I was not toxic against brine shrimp (LC50 value was 3880 μg/ml. Therefore, the extracts could be suitable as antimicrobial and antioxidative agents in food industry.

  9. Surveillance of antimicrobial susceptibility of aerobic and facultative Gram-negative bacilli isolated from patients with intra-abdominal infections in China: the 2002-2009 Study for Monitoring Antimicrobial Resistance Trends (SMART).

    Science.gov (United States)

    Yang, Qiwen; Wang, Hui; Chen, Minjun; Ni, Yuxing; Yu, Yunsong; Hu, Bijie; Sun, Ziyong; Huang, Wenxiang; Hu, Yunjian; Ye, Huifen; Badal, Robert E; Xu, Yingchun

    2010-12-01

    The objective of this study was to investigate the distribution and susceptibility of aerobic and facultative Gram-negative bacilli (GNB) isolated from patients with intra-abdominal infections (IAIs) in China. From 2002 to 2009, minimum inhibitory concentrations of 14 antibiotics for 3420 aerobic and facultative GNB from up to eight hospitals in six cities were determined by the broth microdilution method. Enterobacteriaceae comprised 82.9% (2834/3420) of the total isolates, with Escherichia coli (49.2%) being the most commonly isolated species followed by Klebsiella pneumoniae (17.0%), Enterobacter cloacae (5.8%) and Citrobacter freundii (2.3%). Amongst the antimicrobial agents tested, the three carbapenems (ertapenem, imipenem and meropenem) were the most active agents against Enterobacteriaceae, with susceptibility rates of 96.1-99.6% (2002-2009), 98.2-100% (2002-2009) and 99.6-100% (2002-2004), respectively, followed by amikacin (86.8-95.1%) and piperacillin/tazobactam (84.5-94.3%). Susceptibility rates of all tested third- and fourth-generation cephalosporins against Enterobacteriaceae declined by nearly 30%, with susceptibility rates of 40.2%, 39.1%, 56.3% and 51.8% in 2009 for ceftriaxone, cefotaxime, ceftazidime and cefepime, respectively. The occurrence of extended-spectrum β-lactamases increased rapidly, especially for E. coli (from 20.8% in 2002 to 64.9% in 2009). Susceptibility of E. coli to ciprofloxacin decreased from 57.6% in 2002 to 24.2% in 2009. The least active agent against Enterobacteriaceae was ampicillin/sulbactam (SAM) (25.3-44.3%). In conclusion, Enterobacteriaceae were the major pathogens causing IAIs, and carbapenems retained the highest susceptibility rates over the 8-year study period. Third- and fourth-generation cephalosporins, fluoroquinolones and SAM may not be ideal choices for empirical therapy of IAIs in China. PMID:21036547

  10. Antifungal Susceptibility Testing of Ascomycetous Yeasts Isolated from Animals.

    Science.gov (United States)

    Álvarez-Pérez, Sergio; García, Marta E; Peláez, Teresa; Martínez-Nevado, Eva; Blanco, José L

    2016-08-01

    Recent studies suggest that antifungal resistance in yeast isolates of veterinary origin may be an underdiagnosed threat. We tested a collection of 92 ascomycetous yeast isolates that were obtained in Spain from birds, mammals and insects for antifungal susceptibility. MICs to amphotericin B and azoles were low, and no resistant isolates were detected. Despite these results, and given the potential role of animals as reservoirs of resistant strains, continuous monitoring of antifungal susceptibility in the veterinary setting is recommended. PMID:27216048

  11. Antimicrobial susceptibility pattern of invasive pneumococcal isolates in North West Nigeria

    Directory of Open Access Journals (Sweden)

    Garba Iliyasu

    2015-01-01

    Full Text Available Background: An alarming increase in infections due to penicillin non-susceptible pneumococci (PNSP has been documented in nearly all countries. Increasingly, PNSP are also resistant to other antibiotics, and a growing number of clinical failures following the use of these agents have been reported. Aims: To determine the resistance pattern of pneumococcal isolates from patients with invasive pneumococcal infection in North West Nigeria. Materials and Methods: In a cross-sectional study clinical specimens were obtained from patients with community acquired pneumonia (CAP, meningitis and bacteraemia over a 2 year period. Pneumococcus strains were identified. Isolates were tested against a panel of antibiotics using E-test strips, and interpreted according to the CLSI criteria. 0.06 ΅g/ml was used as break point for penicillin. Analysis was carried out using descriptive statistics; relationships determined using chi-squared or Fisher′s exact tests, with P < 0.05 regarded as significant. Results: Total number of isolates was 132. Twenty-two (16.7% of the isolates were fully sensitive to penicillin while 73 (55.3% and 37 (28.0% were intermediately and fully resistant, respectively. One hundred and twenty-seven (96.2% of the isolates were fully resistant to trimethoprim-sulphamethoxazole. Eleven (8.5% were fully resistant to amoxicillin and 104 (78.8% and 17 (12.9% were intermediately resistant and fully susceptible. One hundred and six (80.3% of the isolates were fully susceptible to chloramphenicol. Resistance to penicillin was shown to infer resistance to other antibiotics. Conclusions: Pneumococcal resistance is common in North West Nigeria. Ceftriaxone retains excellent activity against most of the invasive isolate, while trimethoprim-sulphamethoxazole is almost uniformly resistant.

  12. Polyclonal Mycobacterium avium infections in patients with AIDS: variations in antimicrobial susceptibilities of different strains of M. avium isolated from the same patient.

    Science.gov (United States)

    von Reyn, C F; Jacobs, N J; Arbeit, R D; Maslow, J N; Niemczyk, S

    1995-01-01

    Broth microdilution MICs were determined for pairs of strains isolated from five AIDS patients with polyclonal Mycobacterium avium infection. Four (80%) of the five patients were infected simultaneously with strains having different antimicrobial susceptibility patterns. These findings have implications for the interpretation of susceptibility data in M. avium prophylaxis and treatment trials. PMID:7790424

  13. Polyclonal Mycobacterium avium infections in patients with AIDS: variations in antimicrobial susceptibilities of different strains of M. avium isolated from the same patient.

    OpenAIRE

    von Reyn, C F; Jacobs, N J; Arbeit, R D; Maslow, J.N.; Niemczyk, S

    1995-01-01

    Broth microdilution MICs were determined for pairs of strains isolated from five AIDS patients with polyclonal Mycobacterium avium infection. Four (80%) of the five patients were infected simultaneously with strains having different antimicrobial susceptibility patterns. These findings have implications for the interpretation of susceptibility data in M. avium prophylaxis and treatment trials.

  14. Personalized Genetic Testing and Norovirus Susceptibility

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    Natalie Prystajecky

    2014-01-01

    Full Text Available BACKGROUND: The availability of direct-to-consumer personalized genetic testing has enabled the public to access and interpret their own genetic information. Various genetic traits can be determined including resistance to norovirus through a nonsense mutation (G428A in the FUT2 gene. Although this trait is believed to confer resistance to the most dominant norovirus genotype (GII.4, the spectrum of resistance to other norovirus strains is unknown. The present report describes a cluster of symptomatic norovirus GI.6 infection in a family identified to have norovirus resistance through personalized genetic testing.

  15. MICROBIOLOGY AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OF CASES OF CHRONIC SUPPURATIVE OTITIS MEDIA IN A TERTIARY CARE TEACHING HOSPITAL

    Directory of Open Access Journals (Sweden)

    Vishal Sharma* and Gagandeep Kaur

    2014-05-01

    Full Text Available Chronic suppurative otitis media (CSOM is a chronic inflammation of the middle ear and mastoid cavity that presents as ear discharge. If untreated it can lead to various intracranial and extra cranial complications. This prospective study was carried out to find out various agents causing chronic suppurative otitis media and do determine the antibiogram. A total of 170 patients presenting with ear discharge were included in this study.  Specimen processing, organism isolation, identification and antibiotic susceptibility were performed as per standard protocols. Pseudomonas aeruginosa was the most common organism isolated followed by Staphylococcus aureus, coagulase negative staphylococci, Klebsiella, Proteus, Aspergillus and Candida. Antimicrobial sensitivity pattern of bacterial isolates showed a variable pattern. Of the most common antibiotics available as topical preparations, gentamicin and ciprofloxacin were highly effective against study isolates. Empirical therapy followed by definitive treatment can help prevent emergence of resistance to various antimicrobial agents in these cases.

  16. Technological characterisation, antibiotic susceptibility and antimicrobial activity of wild-type Leuconostoc strains isolated from North Italian traditional cheeses.

    Science.gov (United States)

    Morandi, Stefano; Cremonesi, Paola; Silvetti, Tiziana; Brasca, Milena

    2013-11-01

    Genotypic and technological properties, antibiotic susceptibility and antimicrobial activity of 35 Leuconostoc strains, isolated from different Italian raw milk cheeses, were investigated. RAPD-PCR was used to study genetic variability and to distinguish closely related strains. The results showed a high degree of heterogeneity among isolates. All the strains had weak acidifying activity and showed low proteolytic and lipolytic activities. Reduction activity, was generally low. All the Leuconostoc were susceptible to ampicillin, mupirocin, erythromycin, quinupristin/dalfopristin and tetracycline. Many strains were classified as resistant to oxacillin, ciprofloxacin and nitrofurantonin, while all isolates were found resistant to vancomycin. PCR-based detection did not identify any of the common genetic determinants for vancomycin (vanA, vanB, vanC1, vanC2, vanC3, vanD, vanE, vanG) or erythromycin (ermB and ermC). Tetracycline resistance genes were detected in 25 tetracycline susceptible strains, the most frequent one being tetM. One strain, belonging to Ln. pseudomesenteroides species, was positive for the presence of the int gene of the Tn916/Tn1545 trasposon family. This is the first time the conjugative transposon Tn916 has been detected inside the Leuconostoc species. All strains showed antimicrobial activity against Enterococcus faecalis and Ent. faecium. The presence of genes encoding amino-acid decarboxylases (hdc and tdc) was not detected. Some strains are interesting in view of their use in cheese production as starter and non starter cultures. PMID:24067095

  17. Increasing spectrum in antimicrobial resistance of Shigella isolates in Bangladesh: resistance to azithromycin and ceftriaxone and decreased susceptibility to ciprofloxacin.

    Science.gov (United States)

    Rahman, Mahbubur; Shoma, Shereen; Rashid, Harunur; El Arifeen, Shams; Baqui, A H; Siddique, A K; Nair, G B; Sack, D A

    2007-06-01

    Antimicrobial resistance of Shigella isolates in Bangladesh, during 2001-2002, was studied and compared with that of 1991-1992 to identify the changes in resistance patterns and trends. A significant increase in resistance to trimethoprim-sulphamethoxazole (from 52% to 72%, p or =3 anti-Shigella drugs (multidrug-resistant [MDR]) compared to 52% of 369 strains (p or =32 microg/mL) and had 10-fold higher MIC90 (0.25 microg/mL) to ciprofloxacin than that of nalidixic acid-susceptible strains exhibiting decreased ciprofloxacin susceptibility, which were detected as ciprofloxacin-susceptible and nalidixic acid-resistant by the disc-diffusion method. These strains were frequently associated with MDR traits. High modal MICs were observed to azithromycin (MIC 6 microg/mL) and nalidixic acid (MIC 128 micdrog/mL) and low to ceftriaxone (MIC 0.023 microg/mL). Conjugative R-plasmids-encoded extended-spectrum beta-lactamase was responsible for resistance to ceftriaxone/cefixime. The growing antimicrobial resistance of Shigella is worrying and mandates monitoring of resistance. Pivmecillinam or ciprofloxacin might be considered for treating shigellosis with caution. PMID:17985817

  18. Using Soxhlet Ethanol Extraction to Produce and Test Plant Material (Essential Oils for Their Antimicrobial Properties

    Directory of Open Access Journals (Sweden)

    James Redfern

    2013-11-01

    Full Text Available As the issue of antimicrobial resistance continues to grow, there is a renewed interest in deriving antimicrobial products from natural compounds, particularly extracts from plant materials. This paper describes how essential oil can be extracted from the common herb, thyme (Thymus vulgaris in the classroom. Subsequently, the extract can be tested for its antimicrobial activity. A number of variables are suggested.

  19. Analysis of quorum sensing-dependent virulence factor production and its relationship with antimicrobial susceptibility in Pseudomonas aeruginosa respiratory isolates.

    Science.gov (United States)

    Karatuna, O; Yagci, A

    2010-12-01

    Pseudomonas aeruginosa is an opportunistic pathogen causing severe respiratory infections. The pathogenesis of these infections is multifactorial and the production of many virulence factors is regulated by quorum sensing (QS), a cell-to-cell communication mechanism. The two well defined QS systems in P. aeruginosa, the las and rhl systems, rely on N-acyl homoserine lactone signal molecules, also termed autoinducers. We assessed the activity of QS-dependent virulence factors (including elastase, alkaline protease, pyocyanin and biofilm production) in respiratory isolates of P. aeruginosa and their relationship with antimicrobial susceptibility. We identified sixteen isolates displaying impaired phenotypic activity; among them, eleven isolates were also defective in autoinducer production, and therefore considered QS-deficient. Six of the QS-deficient isolates failed to amplify one or more of the four QS regulatory genes (lasI, lasR, rhlI, rhlR) with PCR: one isolate was negative for rhlR, two isolates were negative for rhlI and rhlR and three isolates were negative for all four genes. The isolates that were negative for virulence factor production were generally less susceptible to the antimicrobials and statistically significant correlations were observed between the lack of elastase production and resistance to piperacillin and ceftazidime; between failure in alkaline protease production and resistance to tobramycin, piperacillin, piperacillin-tazobactam, cefepime, imipenem and ciprofloxacin; and between failure in pyocyanin production and resistance to amikacin, tobramycin, ceftazidime, ciprofloxacin and ofloxacin. The results obtained indicate that, despite the pivotal role of QS in the pathogenesis of P. aeruginosa respiratory infections, QS-deficient strains are still capable of causing infections and tend to be less susceptible to antimicrobials. PMID:20132256

  20. Isolation, identification and antimicrobial susceptibility of Pantoea (Enterobacter agglomerans isolated from consumed powdered infant formula milk (PIF in NICU ward: First report from Iran.

    Directory of Open Access Journals (Sweden)

    Jalal Mardaneh

    2013-09-01

    Full Text Available Pantoea agglomerans is a Gram-negative rod in the Enterobacteriaceae family. It is reported as both commensal and opportunistic pathogen of animals and humans. This organism is potential candidates as powdered infant milk formula-borne opportunistic pathogen. The aim of our study was to perform isolation, identification and antimicrobial susceptibility pattern of Pantoea (Enterobacter agglomerans strains isolated from consumed powdered infant formula milk (PIF in NICU ward.A of total 125 powdered infant formula milk (PIF samples were purchased from hospital drug stores between June 2011 to March 2012. P. agglomerans was isolated according to FDA method. For final confirmation, biochemical tests embedded in the API-20E system were used. The drug susceptibility test was performed using the disc diffusion method according to CLSI guidelines.Out of the 125 samples investigated, 8 (6.4% samples were positive for P. agglomerans and these were uniformly susceptible to tigecycline, chloramphenicol, cefepime, levofloxacin, minocycline and colistin. Fifty percent of isolates were resistant to cefotaxime, moxifloxacin, cotrimoxazole and ticarcillin.Controlling the primary populations of P. agglomerans during the PIF production process and preventing post processing contamination, by using suitable microbiological guidelines, is accessible. Sanitary practices for the preparation of infant formula in both the home and hospitals should be carefully controlled.

  1. Serological characterization and antimicrobial susceptibility of Streptococcus suis isolates from diagnostic samples in Denmark during 1995 and 1996

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Jorsal, Sven Erik Lind; Jensen, N. E.

    1998-01-01

    antimicrobial agents. The majority of cases were lung diseases (57%), followed by septicaemia (16%), meningitis (15%) and endocarditis (8%). Almost 96% of the isolates could be typed using the 28 antisera. The most common serotype was serotype 2 (29%), followed by serotype 7 (17%), and serotypes 3, 4 and 8 (9...... resistant to lincomycin and spiramycin. The differences in susceptibility between isolates of serotype 2 and the other serotypes were statistically significant. Compared to a previous Danish study the distribution of serotypes of S. suis causing infections among pigs in Denmark has changed during the last...

  2. In vitro antimicrobial activity of linezolid tested against vancomycin-resistant enterococci isolated in Brazilian hospitals

    Directory of Open Access Journals (Sweden)

    Reis Adriana O.

    2001-01-01

    Full Text Available The emergence of vancomycin-resistant enterococci (VRE has been described recently in Brazil. This is in contrast to the USA and Europe, where the VRE appeared in the late 1980s. The progressive increase in VRE isolation poses important problems in the antimicrobial therapy of nosocomial infections. Treatment options and effective antimicrobial agents for VRE are often limited and the possibility of transfer of vancomycin genes to other Gram-positive microorganisms continues. In the search for antimicrobial agents for multiresistant Gram-positive cocci, compounds such as linezolid and quinupristin/dalfopristin have been evaluated. The present study was conducted to evaluate the in vitro activity of the oxazolidinone linezolid and 10 other antimicrobial agents, including quinupristin-dalfopristin, against multiresistant enterococci isolated in Brazilian hospitals. Thirty-three vancomycin resistant isolates (17 Enterococcus faecium and 16 E. faecalis, were analyzed. Strains were isolated from patients at São Paulo Hospital, Oswaldo Cruz Hospital, Hospital do Servidor Público Estadual, Santa Marcelina Hospital, Santa Casa de Misericórdia de São Paulo, and Hospital de Clínicas do Paraná. The samples were tested by a broth microdilution method following the National Committee for Clinical Laboratory Standards (NCCLS recommendations. All isolates were molecular typed using pulsed-field gel electrophoresis (PFGE. Linezolid was the most active compound against these multiresistant enterococci, showing 100% inhibition at the susceptible breakpoints. Quinupristin/dalfopristin and teicoplanin showed poor activity against both species. The molecular typing results suggest that there has been interhospital spread of vancomycin resistant E. faecium and E. faecalis among Brazilian hospitals. The results of this study indicate that linezolid is an appropriate therapeutic option for the treatment of vancomycin-resistant enterococci infections in Brazil.

  3. In vitro antimicrobial activity of linezolid tested against vancomycin-resistant enterococci isolated in Brazilian hospitals.

    Science.gov (United States)

    Reis, A O; Cordeiro, J C; Machado, A M; Sader, H S

    2001-10-01

    The emergence of vancomycin-resistant enterococci (VRE) has been described recently in Brazil. This is in contrast to the USA and Europe, where the VRE appeared in the late 1980s. The progressive increase in VRE isolation poses important problems in the antimicrobial therapy of nosocomial infections. Treatment options and effective antimicrobial agents for VRE are often limited and the possibility of transfer of vancomycin genes to other Gram-positive microorganisms continues. In the search for antimicrobial agents for multiresistant Gram-positive cocci, compounds such as linezolid and quinupristin/dalfopristin have been evaluated. The present study was conducted to evaluate the in vitro activity of the oxazolidinone linezolid and 10 other antimicrobial agents, including quinupristin-dalfopristin, against multiresistant enterococci isolated in Brazilian hospitals. Thirty-three vancomycin resistant isolates (17 Enterococcus faecium and 16 E. faecalis), were analyzed. Strains were isolated from patients at São Paulo Hospital, Oswaldo Cruz Hospital, Hospital do Servidor Público Estadual, Santa Marcelina Hospital, Santa Casa de Misericórdia de São Paulo, and Hospital de Clínicas do Paraná. The samples were tested by a broth microdilution method following the National Committee for Clinical Laboratory Standards (NCCLS) recommendations. All isolates were molecular typed using pulsed-field gel electrophoresis (PFGE). Linezolid was the most active compound against these multiresistant enterococci, showing 100% inhibition at the susceptible breakpoints. Quinupristin/dalfopristin and teicoplanin showed poor activity against both species. The molecular typing results suggest that there has been interhospital spread of vancomycin resistant E. faecium and E. faecalis among Brazilian hospitals. The results of this study indicate that linezolid is an appropriate therapeutic option for the treatment of vancomycin-resistant enterococci infections in Brazil. PMID:11779450

  4. Aerobic and anaerobic susceptibility tests with three tetracyclines. Reassessment of the "class concept" of disk testing.

    Science.gov (United States)

    Barry, A L; Draper, D L; Wong, M K

    1978-11-01

    Both aerobic and anaerobic susceptibility tests were performed with tetracycline, doxycycline, and minocycline, using disk diffusion and agar dilution technics. The data were examined in order to reassess the concept of testing a single disk, representative of the tetracycline class of antimicrobics. All strains that were susceptible to a tetracycline disk were predictably susceptible to the tetracycline analogs. Some strains that gave zones in the resistant or intermediate range were susceptible or moderately susceptible to doxycycline and minocycline by agar dilution methods. However, disk tests with the more active analogs were often unproductive, since most tetracycline-resistant strains gave indeterminate results with doxycycline or minocycline disks. It was concluded that the "class concept" of disk testing is still appropriate and that tests with tetracycline disks predict susceptibility to the other tetracycline analogs reasonably well. PMID:717289

  5. Bacterial pathogens and their antimicrobial susceptibility in Otukpo Benue state of Nigeria

    Institute of Scientific and Technical Information of China (English)

    Okwori EE; Nwadioha SI; Nwokedi EOP; Odimayo M; Jombo GTA

    2011-01-01

    Objective:To isolate bacterial pathogens and test for their antibiotic susceptibility. Methods:A total of 20 000 samples from 9 different clinical sites were processed in the laboratory between 1987 to 2000. The specimens were inoculated on the appropriate media for the isolation of the bacteria. Biochemical and serology tests were carried out on the organisms to confirm the type of bacteria isolated. Antibiotic susceptibility test was also carried out on each of the bacteria isolated. Results:A total of 18 520 bacteria were isolated from the specimens. The specimens were from nine different clinical sites, i.e. wound accounted for 22.84%, urine 31.67%, blood 12.38%, genital 7.70%, sputum 6.81%, stool 6.28%, cerebrospinal fluid 5.98%, aspirates 3.85%and ear/throat swabs were 2.49%. Gram negative bacteria accounted for 76%of isolates. The main species were Pseudomonas 2 238 (12.08%), Escherichia coli (E. coli) 2 073 (11.19%) and Staphylococcus aureus (S. aureus) which accounted for 2 511 (13.56%) of the total isolates. S. aureus showed 70%and 65%resistance to penicillin and ampicillin, respectively. Surprisingly, 40%of the organism was resistant to cloxacillin. E. coli showed 47%and 42%resistance to ampicillin and gentamicin, respectively. 49%of Salmonella typhi was resistant to chloramphenicol while 37%of Neisseria meningitidis was resistant to penicillin. Conclusions: The rate of bacteria isolated from the clinical specimens is high and antibiotic sensitivity pattern of the organisms vary from one antibiotic to the other.

  6. Antimicrobial drug susceptibility of Leptospira interrogans serovar hardjo isolated from cattle.

    OpenAIRE

    Prescott, J.F.; Nicholson, V M

    1988-01-01

    The susceptibility to commonly used drugs of 18 isolates of Leptospira hardjo from the kidneys of feedlot cattle from different sources was determined quantitatively. All isolates were susceptible to penicillin G, ampicillin, tetracycline, erythromycin and streptomycin. Susceptibility to sulphamethazine was ambiguous. No drug resistance was detected and the results were similar to those described for other serovars.

  7. Antimicrobial Susceptibility and Plasmid Replicon Typing of Salmonella enterica serovar Kentucky isolates recovered from Broilers

    Science.gov (United States)

    Salmonella Kentucky has become the predominate serotype recovered from broiler slaughter in the United States and the prevalence of antimicrobial resistance (AMR) has increased dramatically in this serotype. Relationships between AMR, genotype, and plasmid replicon types were characterized for 600 ...

  8. Staphylococcus aureus small colony variants are susceptible to light activated antimicrobial agents

    OpenAIRE

    Tubby, S.; Wilson, M.; Wright, J A; Zhang, P.; Nair, S. P.

    2013-01-01

    Background: Antibiotic therapy can select for small colony variants of Staphylococcus aureus that are more resistant to antibiotics and can result in persistent infections, necessitating the development of more effective antimicrobial strategies to combat small colony variant infections. Photodynamic therapy is an alternative treatment approach which utilises light in combination with a light-activated antimicrobial agent to kill bacteria via a non-specific mechanism of action. In...

  9. THE EFFECTIVENESS OF ANTIMICROBIAL PRESERVATIVES TESTING OF THE MEDICINE "EFIAL"

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    Borshchevskiy GI

    2015-04-01

    Full Text Available Dosage form - spray is one of the most advanced and modern methods of medicines administration in the human body. The advantage of airborne mode of medicines delivery (inhalation than injection and enterable methods is the ability to direct and rapid impact on the area of inflammation of the mucous membranes or when fine evaporation - on the bronchi and lungs. When finished medicinal product itself has not a sufficient antimicrobial activity, in its composition can be administered antimicrobial preservatives, which is especially important for medicines as aqueous solutions. Because microbial contamination can cause infection of the patient or damage to the finished product, antimicrobial preservatives are designed to prevent microbial contamination of the finished medicinal product during storage and use, especially in the case of multi-container packaging. Rationale of composition and technology of spray “Efial” was conducted by us using physical, chemical and technological methods. An important task in creating new medicines is the study of preservatives choice. The aim of this work is to test the effectiveness of antimicrobial preservatives of spray “Efial”. Material & methods The object of the test – “Efial”containing preservatives on the lower: series 10814 (holding inoculated samples at a temperature of 20-25 º C and series 10914 (holding inoculated samples at 2-8 º C. Materials: 1. Nutrient medium: soy-casein agar, sabourodextrose agar. 2. Solutions: buffer solution of sodium chloride and peptone pH =7.0, containing 50 g/l of polysorbate-80, 5 g/l of lecithin, 1 g/l of histidine hydrochloride. Test-microorganisms: Staphylococcus aureus ATCC 6538; Pseudomonas aeruginosa ATCC 9027; Candida albicans ATCC 10231; Aspergillus brasiliensis АТСС 16404. Preparation of inoculums was carried by State Pharmacopoeia of Ukraine, p. 5.1.3. Results & discussion The checks of methods for determining total viable microorganisms

  10. Intravascular catheter related infections and antimicrobial susceptibility pattern of isolated bacteria in a tertiary care hospital of Bangladesh

    Directory of Open Access Journals (Sweden)

    F J Mansur

    2014-01-01

    Full Text Available The aim of this study was to evaluate the rate of bacterial colonisation and catheter related blood stream infections (CRBSI together with the antibiotic susceptibility patterns in a tertiary care hospital. CRBSI was detected with semi-quantitative and quantitative methods. The antimicrobial susceptible patterns of the isolated organisms were performed by Kirby Bauer disk diffusion method. The rate of catheter colonisation and CRBSI were 42.1% and 14% (16.1/1000 catheter days respectively. The most common causative pathogens were Pseudomonas sp. (23.7%, Acinetobacter sp. (18.4%, Staphylococcus aureus (13.2% and Enterobacteriaceae (10.5%. The rate of isolation of methicillin resistance S. aureus, imipenem resistant Pseudomonas sp. and extended spectrum β lactamase producing Enterobacteriaceae were 60%, 44.0% and 100%. The result of this study would be useful for control and treatment of CRBSI.

  11. The Activity of Antimicrobial Surfaces Varies by Testing Protocol Utilized

    Science.gov (United States)

    Campos, Matias D.; Zucchi, Paola C.; Phung, Ann; Leonard, Steven N.; Hirsch, Elizabeth B.

    2016-01-01

    Background Contaminated hospital surfaces are an important source of nosocomial infections. A major obstacle in marketing antimicrobial surfaces is a lack of efficacy data based on standardized testing protocols. Aim We compared the efficacy of multiple testing protocols against several “antimicrobial” film surfaces. Methods Four clinical isolates were used: one Escherichia coli, one Klebsiella pneumoniae, and two Staphylococcus aureus strains. Two industry methods (modified ISO 22196 and ASTM E2149), a “dried droplet”, and a “transfer” method were tested against two commercially available antimicrobial films, one film in development, an untreated control, and a positive (silver) control film. At 2 (only ISO) and 24 hours following inoculation, bacteria were collected from film surfaces and enumerated. Results Compared to untreated films in all protocols, there were no significant differences in recovery on either commercial brand at 2 or 24 hours after inoculation. The silver surface demonstrated significant microbicidal activity (mean loss 4.9 Log10 CFU/ml) in all methods and time points with the exception of 2 hours in the ISO protocol and the transfer method. Using our novel droplet method, no differences between placebo and active surfaces were detected. The surface in development demonstrated variable activity depending on method, organism, and time point. The ISO demonstrated minimal activity at 2 hours but significant activity at 24 hours (mean 4.5 Log10 CFU/ml difference versus placebo). The ASTEM protocol exhibited significant differences in recovery of staphylococci (mean 5 Log10 CFU/ml) but not Gram-negative isolates (10 fold decrease). Minimal activity was observed with this film in the transfer method. Conclusions Varying results between protocols suggested that efficacy of antimicrobial surfaces cannot be easily and reproducibly compared. Clinical use should be considered and further development of representative methods is needed. PMID

  12. Virulence determinants, antimicrobial susceptibility, and molecular profiles of Erysipelothrix rhusiopathiae strains isolated from China.

    Science.gov (United States)

    Ding, Yi; Zhu, Dongmei; Zhang, Jianmin; Yang, Longsheng; Wang, Xiangru; Chen, Huanchun; Tan, Chen

    2015-11-01

    The aim of this study was to understand the epidemiology, serotype, antibiotic sensitivity, and clonal structure of Erysipelothrix rhusiopathiae strains in China. Forty-eight strains were collected from seven provinces during the period from 2012 to 2013. Pulse-field electrophoresis identified 32 different patterns which were classified into clonal groups A–D. Most pulsed-field gel electrophoresis (PFGE) patterns were observed in clonal complex A and B, suggesting high diversity of genetic characterization in these two predominant clonal complexes. Antibiotic sensitivity test shows that all the stains were susceptible to ampicillin, erythromycin, and cefotaxime, and resistant to kanamycin, cefazolin, sulfadiazine, and amikacin. Erythromycin and ampicillin are recommended as first-line antibiotics for treatment of E. rhusiopathiae in China. The high variation in PFGE pattern among the main clonal groups shows that the E. rhusiopathiae in China may originate from different lineages and sources instead of from expansion of a single clonal lineage across different regions. PMID:26975059

  13. Agar dilution method for susceptibility testing of Neisseria gonorrhoeae

    Directory of Open Access Journals (Sweden)

    Marta C de Castillo

    1996-12-01

    Full Text Available The antibiotic susceptibilities of Neisseria gonorrhoeae isolates obtained from patients attending a clinic for sexually transmitted diseases in Tucumán, Argentina, were determined by the agar dilution method (MIC. 3.5% of the isolates produced ²-lactamase. A total of 96.5% of ²-lactamase negative isolates tested were susceptible to penicillin (MIC < 2 µgml-1; 14.03% of the tested isolates were resistant to tetracycline (MIC < 2 µgml-1, and 98% of the tested isolates were susceptible to spectinomycin (MIC < 64 µgml-1. The MICs for 95% of the isolates, tested for other drugs were: < 2 µgml-1 for cefoxitin, < 0.06 µgml-1 for cefotaxime, < 0.25 µgml-1 for norfloxacin, < 10 µgml-1 for cephaloridine, < 10 µgml-1 for cephalexin, and < 50 µgml-1 for kanamycin. Antibiotic resistance among N. gonorrhoeae isolates from Tucumán, Argentina, appeared to be primarily limited to penicillin and tetracycline, which has been a general use against gonorrhoeae in Tucumán since 1960. Periodic monitoring of the underlying susceptibility profiles of the N. gonorrhoeae strains prevalent in areas of frequent transmission may provide clues regarding treatment options and emerging of drug resistance.

  14. Susceptibility of Gardnerella vaginalis biofilms to natural antimicrobials subtilosin, ε-poly-L-lysine, and lauramide arginine ethyl ester.

    Science.gov (United States)

    Turovskiy, Yevgeniy; Cheryian, Thomson; Algburi, Ammar; Wirawan, Ruth E; Takhistov, Paul; Sinko, Patrick J; Chikindas, Michael L

    2012-01-01

    Bacterial vaginosis is a common vaginal infection associated with numerous gynecological and obstetric complications. This condition is characterized by the presence of thick adherent vaginal biofilms, composed mainly of Gardnerella vaginalis. This organism is thought to be the primary aetiological cause of the infection paving the way for various opportunists to colonize the niche. Previously, we reported that the natural antimicrobials subtilosin, ε-poly-L-lysine, and lauramide arginine ethyl ester selectively inhibit the growth of this pathogen. In this study, we used plate counts to evaluate the efficacy of these antimicrobials against established biofilms of G. vaginalis. Additionally, we validated and compared two rapid methods (ATP viability and resazurin assays) for the assessment of cell viability in the antimicrobial-treated G. vaginalis biofilms. Out of the tested antimicrobials, lauramide arginine ethyl ester had the strongest bactericidal effect, followed by subtilosin, with clindamycin and polylysine showing the weakest effect. In comparison to plate counts, ATP viability and resazurin assays considerably underestimated the bactericidal effect of some antimicrobials. Our results indicate that these assays should be validated for every new application. PMID:23024575

  15. Screening probiotic strains for safety: Evaluation of virulence and antimicrobial susceptibility of enterococci from healthy Chinese infants.

    Science.gov (United States)

    Zhang, Fen; Jiang, Meiling; Wan, Cuixiang; Chen, Xiaoyan; Chen, Xiaoyong; Tao, Xueying; Shah, Nagendra P; Wei, Hua

    2016-06-01

    The aim of this study was to evaluate the safety of enterococci isolated from Chinese infants and screen out potential probiotic candidates. One hundred eight strains were isolated from feces of 34 healthy infants, and 38 strains of Enterococcus spp. were categorized as follows: E. faecalis (22), E. faecium (10), E. hirae (3), E. durans (2), and E. casseliflavus (1). Of these, 72.7% of E. faecalis came from infants delivered by cesarean and 62.5% of E. faecium from infants delivered vaginally. For safety evaluation of strains, we determined presence of virulence genes; production of hemolysin, gelatinase, and biofilm; and antimicrobial susceptibility of enterococci. Six out of 14 virulence genes were detected with a distribution of gelE (26.3%), cylA (39.4%), esp (15.8%), efaA (63.2%), asa1 (50.0%), and ace (50.0%). In phenotype analysis, 36.8% of the strains exhibited positive hemolytic activity and 17.5% were positive for production of gelatinase. Results of antimicrobial susceptibility showed that different percentages of the strains were resistant to ciprofloxacin (5.2%), vancomycin (7.8%), rifampicin (10.5%), erythromycin (52.6%), and gentamycin (52.6%); remarkably, none of the strains were resistant to ampicillin or chloramphenicol. In total, 10 strains, including 6 E. faecium, which are free of virulence determinants and sensitive to common antimicrobial agents (e.g., ampicillin and vancomycin), were further assessed for their probiotic properties. All strains survived well in simulated gastric fluid and intestinal tract, with maximum reductions of 0.600 and 0.887 log cfu/mL, respectively. Six strains of E. faecium could resist 0.3 to 1.0% bile salt, of which E. faecium WEFA23 presented the highest growth (75.06%) at 1.0% bile salt. All strains showed bile salt hydrolase activity on glycodeoxycholic acid, but only 3 of E. faecium showed activity on taurodeoxycholic acid. These results deliver useful information on the safety of enterococci in infants in

  16. NEW ANTIMICROBIAL SENSITIVITY TESTS OF BIOFILM OF STREPTOCOCCUS MUTANS IN ARTIFICIAL MOUTH MODEL

    Institute of Scientific and Technical Information of China (English)

    李鸣宇; 汪俊; 刘正; 朱彩莲

    2004-01-01

    Objective To develop a new antimicrobial sensitivity test model for oral products in vitro.Methods A biofilm artificial mouth model for antimicrobial sensitivity tests was established by modifying the LKI chromatography chamber. Using sodium fluoride and Tea polyphenol as antimicrobial agent and Streptococcus mutans as target, sensitivity tests were studied. Results The modeling biofilm assay resulted in a MIC of 1.28mg/ml for fluoride against S. mutans, which was 32 times the MIC for broth maco-dilution method. The differential resistance of bacteria bioflim to antimicrobial agent relative to planktonic cells was also demonstrated. Conclusion The biofilm artificial mouth model may be useful in oral products test.

  17. Resistance to antimicrobial agents used for animal therapy in pathogenic , zoonotic and indicator bacteria isolated from different food animals in Denmark: A baseline study for the Danish Integrated Antimicrobial Resistance Monitoring Programme (DANMAP)

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Bager, Flemming; Jensen, N. E.; Madsen, M.; Meyling, A.; Wegener, Henrik Caspar

    1998-01-01

    collected from October 1995 through December 1996 were tested for susceptibility to all major classes of antimicrobial agents used for therapy in Denmark. Bacterial species intrinsically resistant to an antimicrobial were not tested towards that antimicrobial. Acquired resistance to all antimicrobials was...

  18. Species distribution and antimicrobial susceptibility of gram-negative aerobic bacteria in hospitalized cancer patients

    Directory of Open Access Journals (Sweden)

    El-Sharif Amany

    2009-02-01

    Full Text Available Abstract Background Nosocomial infections pose significant threats to hospitalized patients, especially the immunocompromised ones, such as cancer patients. Methods This study examined the microbial spectrum of gram-negative bacteria in various infection sites in patients with leukemia and solid tumors. The antimicrobial resistance patterns of the isolated bacteria were studied. Results The most frequently isolated gram-negative bacteria were Klebsiella pneumonia (31.2% followed by Escherichia coli (22.2%. We report the isolation and identification of a number of less-frequent gram negative bacteria (Chromobacterium violacum, Burkholderia cepacia, Kluyvera ascorbata, Stenotrophomonas maltophilia, Yersinia pseudotuberculosis, and Salmonella arizona. Most of the gram-negative isolates from Respiratory Tract Infections (RTI, Gastro-intestinal Tract Infections (GITI, Urinary Tract Infections (UTI, and Bloodstream Infections (BSI were obtained from leukemic patients. All gram-negative isolates from Skin Infections (SI were obtained from solid-tumor patients. In both leukemic and solid-tumor patients, gram-negative bacteria causing UTI were mainly Escherichia coli and Klebsiella pneumoniae, while gram-negative bacteria causing RTI were mainly Klebsiella pneumoniae. Escherichia coli was the main gram-negative pathogen causing BSI in solid-tumor patients and GITI in leukemic patients. Isolates of Escherichia coli, Klebsiella, Enterobacter, Pseudomonas, and Acinetobacter species were resistant to most antibiotics tested. There was significant imipenem -resistance in Acinetobacter (40.9%, Pseudomonas (40%, and Enterobacter (22.2% species, and noticeable imipinem-resistance in Klebsiella (13.9% and Escherichia coli (8%. Conclusion This is the first study to report the evolution of imipenem-resistant gram-negative strains in Egypt. Mortality rates were higher in cancer patients with nosocomial Pseudomonas infections than any other bacterial infections

  19. NFECTIONS BY MULTIDRUG RESISTANT ORGANISMS IN A NEUROSURGICAL AND NEUROPSYCHIATRIC CARE CENTRE AND THE CHANGING ANTIMICROBIAL SUSCEPTIBILITY PATTERNS.

    Directory of Open Access Journals (Sweden)

    Ravikumar

    2012-10-01

    Full Text Available ABSTRACT: BACKGROUND: Infections contribute to major morbidity and morta lity in the developing countries. Antimicrobial resistance is an other major problem with the increasing infections and non availability of ideal antimicrob ial agent. Despite the advances in antimicrobial therapy, infections remain a serious b urden. This study was designed t o assess the increasing infection rates and antimicrobial su sceptibility patterns in neurosurgical and neuropsychiatric patients. Over a period of three years and six months from Jan uary 2009 to June 2012, various samples were processed, isolated the infectious agent and identified. The different samples included samples like CSF, urine, pus, tracheal aspira tes, shunt & catheter tips, tissue and blood. These were assessed for antimicrobial susceptibility patterns by conventional and automated culture and sensitivity systems. The results were t hen statistically analyzed. This study found that in general, there is a trend towards increased rates of infections, the majority of which were caused by Multi Drug Res istant Gram Negative Bacilli (MDRGNB, followed by Candida species and Cryptococcus species, Methicillin Resistant Staphylococcus aureus (MRSA, and Mycobacterium tuberculosis. The infection rates, from January 2009 to June 2012, were 3.7% to 5.1% for MDRGNB, 2.89% to 4.24% for Candida, 2.93% to 3.13% for Cryptococcus, 2.8% to 2.1%(till June 2012 for MRSA and 1.3% to 5.7% for Mycobacterium tuberculosis. Also, a trend towards increasing resi stance among the isolates to the carbapenem antibiotics was observed. The increasing trend of infections is a cause for c oncern throughout the country. Indiscriminate use of antibiotics, hospital personnel not adhering to safety precautions etc are the main reasons for the increased infection rates. Newer therapeutic agents and strict antibiotic policies are required to effectively cont rol the issue of emerging infections.

  20. Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

    Directory of Open Access Journals (Sweden)

    Gonzalo Castillo-Rojas

    Full Text Available Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation, respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE. E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

  1. Susceptibility of anaerobic bacteria to sulfamethoxazole/trimethoprim and routine susceptibility testing.

    Science.gov (United States)

    Wüst, J; Wilkins, T D

    1978-09-01

    The minimal inhibitory concentrations (MICs) of sulfamethoxazole and trimethoprim against 144 strains of obligately anaerobic bacteria were determined on Diagnostic Sensitivity Test agar (Oxoid) or in prereduced Diagnostic Sensitivity Test broth, both supplemented with sodium pyruvate (1 mg/ml), hemin (5 mug/ml), and vitamin K(1) (1 mug/ml). Fifty-eight percent of the strains were susceptible to sulfamethoxazole alone (MIC disk test proposed by Wilkins and Thiel, modified by using prereduced Diagnostic Sensitivity Test broth instead of brain heart infusion broth and by using a smaller inoculum, there was over 90% correlation with the MICs. Poor results were found when the broth-disk tests were performed in brain heart infusion broth. There was very poor correlation between inhibition zone diameters by an agar diffusion method and MICs. PMID:708016

  2. Impact of restriction of cefepime use on the antimicrobial susceptibility of Gram-negative bacilli related to healthcare-associated infections in an orthopedic hospital

    Directory of Open Access Journals (Sweden)

    Rossi F

    2011-08-01

    Full Text Available Priscila R Oliveira1, Adriana P Paula1, Karine Dal-Paz1, Cassia S Felix1, Flavia Rossi2, Jorge S Silva1, Ana Lucia M Lima11Orthopaedics and Traumatology Department, 2Pathology Department, University of São Paulo, São Paulo, BrazilIntroduction: In recent decades, antimicrobial resistance has become a public health problem, particularly in cases of healthcare-associated infections. Interaction between antibiotic consumption and resistance development is of particular interest regarding Gram-negative bacilli, whose growing resistance has represented a great challenge.Objective: Assess the impact of restriction of cefepime use on antimicrobial susceptibility among the Gram-negative bacilli (GNB most frequently involved in healthcare-associated infections (HAI.Methods: Data relating to hospital occupancy and mortality rates, incidence of HAI, incidence of GNB as causative agents of HAI, antimicrobial consumption at the hospital and antimicrobial susceptibility of GNB related to HAI were compared between two periods: a 24-month period preceding restriction of cefepime use and a 24-month period subsequent to this restriction.Results: There was a significant drop in cefepime consumption after its restriction. Susceptibility of Acinetobacter baumanii improved relating to gentamicin, but it worsened in relation to imipenem, subsequent to this restriction. For Pseudomonas aeruginosa, there was no change in antimicrobial susceptibility. For Klebsiella pneumoniae and Enterobacter spp, there were improvements in susceptibility relating to ciprofloxacin.Conclusion: Restriction of cefepime use had a positive impact on K. pneumoniae and Enterobacter spp, given that after this restriction, their susceptibilities to ciprofloxacin improved. However, for A. baumanii, the impact was negative, given the worsening of susceptibility to imipenem.Keywords: ecological studies, cross infection, drug resistance, microbial, Gram-negative bacilli, cefepime

  3. Antimicrobial susceptibility and occurrence of resistance genes among Salmonella enterica serovar Weltevreden from different countries

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Lertworapreecha, M.; Evans, M.C.;

    2003-01-01

    Objectives: This study was conducted to investigate the occurrence of antimicrobial resistance among Salmonella Weltevreden isolates from different sources in South-East Asia (Indonesia, Laos, Malaysia, Taiwan, Thailand, Vietnam), Australia, Denmark, New Zealand and the USA. Methods: A total of 503...

  4. Antimicrobial susceptibility and genotyping analysis of Hungarian Neisseria gonorrhoeae strains in 2013.

    Science.gov (United States)

    Nemes-Nikodém, Éva; Brunner, Alexandra; Pintér, Dóra; Mihalik, Noémi; Lengyel, György; Marschalkó, Márta; Kárpáti, Sarolta; Szabó, Dóra; Ostorházi, Eszter

    2014-12-01

    Emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is a major public health concern worldwide. The current study aims to determine the antimicrobial resistance in N. gonorrhoeae and associated molecular typing to enhance gonococcal antimicrobial surveillance in Hungary. In the National N. gonorrhoeae Reference Laboratory of Hungary 187 N. gonorrhoeae infections were detected in 2013, antibiograms were determined for all the isolated strains, and 52 (one index strain from every sexually contact related group) of them were also analysed by the N. gonorrhoeae multi-antigen sequence typing (NG-MAST) method. Twenty-two different NG-MAST sequence types (STs) were identified, of which 8 STs had not been previously described. In Hungary, the highly diversified gonococcal population displayed high resistance to penicillin, ciprofloxacin and tetracycline (the antimicrobials previously recommended for gonorrhoea treatment). Resistance to the currently recommended extended spectrum cephalosporines were rare: only two of the expected strains, an ST 1407 and an ST 210, had cefixime MIC above the resistance breakpoint. By the revision of our National Treatment Guideline, it must be considered, that the azithromycin resistance is about 60% among the four most frequently isolated STs in Hungary. PMID:25496972

  5. Antimicrobial susceptibility of Clostridium difficile isolated from food animals on farms

    Science.gov (United States)

    Clostridium difficile is commonly associated with a spectrum of disease in humans referred to as C. difficile-associated disease (CDAD) and use of antimicrobials is considered a risk factor for development of disease in humans. Clostridium difficile can also inhabit healthy food animals and transmi...

  6. Evaluation of BACTEC Mycobacteria Growth Indicator Tube (MGIT 960) Automated System for Drug Susceptibility Testing of Mycobacterium tuberculosis

    OpenAIRE

    Ardito, Fausta; Posteraro, Brunella; Sanguinetti, Maurizio; Zanetti, Stefania; Fadda, Giovanni

    2001-01-01

    The reliability of the BACTEC MGIT 960 system, an automated version of the Mycobacteria Growth Indicator Tube (MGIT), for antimicrobial susceptibility testing of Mycobacterium tuberculosis was evaluated on 78 clinical isolates. Rifampin (RMP), isoniazid (INH), streptomycin (SM), and ethambutol (EMB) were tested at the following concentrations: 1.0 μg/ml for RMP, 0.1 and 0.4 μg/ml for INH, 1.0 and 4.0 μg/ml for SM, and 5.0 and 7.5 μg/ml for EMB. Results were compared with those obtained by the...

  7. Investigation into the susceptibility of Burkholderia cepacia complex isolates to photodynamic antimicrobial chemotherapy (PACT)

    Science.gov (United States)

    Cassidy, C. M.; Watters, A. L.; Donnelly, R. F.; Tunney, M. M.

    2009-06-01

    The main cause of morbidity and mortality in cystic fibrosis (CF) sufferers is progressive pulmonary damage caused by recurrent and often unremitting respiratory tract infection. Causative organisms include Pseudomonas aeruginosa and Haemophilus influenzae, but in recent years the Burkholderia cepacia complex has come to the fore. This group of highly drug-resistant Gram-negative bacteria are associated with a rapid decline in lung function and the often fatal cepacia syndrome, with treatment limited to patient segregation and marginally effective antibacterial regimens. Thus, development of an effective treatment is of the upmost importance. PACT, a non-target specific therapy, has proven successful in killing both Gram-positive and Gram-negative bacteria. In this study, planktonic cultures of six strains of the B. cepacia complex were irradiated (635 nm, 200 J cm-2,10 minutes irradiation) following 30 seconds incubation with methylene blue (MB) or meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP). Rates of kill of > 99 % were achieved with MB- and TMP-PACT. A MB concentration of 50 μg ml-1 and TMP concentration of 500 μg ml-1 were associated with highest percentage kills for each photosensitizer. PACT is an attractive option for treatment of B.cepacia complex infection. Further study, involving biofilm culture susceptibility, delivery of light to the target and in vivo testing will be necessary before it PACT becomes a viable treatment option for CF patients who are colonised or infected with B. cepacia complex.

  8. The bacteriology and antimicrobial susceptibility of infected and non-infected dog bite wounds: fifty cases.

    Science.gov (United States)

    Meyers, Bruce; Schoeman, Johan P; Goddard, Amelia; Picard, Jackie

    2008-03-18

    Dog bite wounds are a common reason for dogs requiring veterinary care, but there is surprisingly little data on the bacteriology of bite wounds. A prospective study was performed on dogs with various grades of bite wound to identify the bacteria present in these wounds. Swabs were collected from all wounds for bacterial culture and cytology. All swabs were cultured aerobically and anaerobically and all aerobic cultures were evaluated for antibiotic susceptibility using the Kirby Bauer disk diffusion test. Fifty dogs with 104 bite wounds, inflicted within the previous 72h, were included. The victims were predominately intact male small breed dogs. Of the 104 wounds, 21 were judged by cytology to be infected and 83 non-infected. Infected wounds were significantly more likely to culture positive (p=0.02). Sixteen percent of wounds showed no growth. Sixteen percent grew aerobes, 1% anaerobes and 67% a mixture of aerobes and anaerobes. Pasteurella canis and pyogenic streptococci were common in infected wounds, whereas Bacillus spp., Actinomyces spp. and the oral streptococci were usually found in contaminated wounds. Three anaerobic genera were cultured, namely, Prevotella, Clostridium and Peptostreptococcus. One case represented the first isolation of Capnocytophaga canimorsus in an infected dog bite wound. Although no single antibiotic therapy was considered to be effective against all the bacteria, amoxycillin plus clavulanic acid, 1st and 3rd generation cephalosporins ampicillin or amoxycillin and potentiated sulphonamides gave the best in vitro sensitivity results. PMID:18029118

  9. In vitro susceptibility testing of Paracoccidioides brasiliensis to sulfonamides.

    OpenAIRE

    Restrepo, A; Arango, M D

    1980-01-01

    A total of 60 clinical isolates of Paracoccidioides brasiliensis were tested for susceptibility to sulfadiazine and sulfadimethoxyne by the agar dilution technique. A modification of the Mueller-Hinton medium was devised which gave good growth of the yeast form. The minimum inhibitory concentrations for only 51.6% of the isolates were in the range of the recommended blood serum concentration (50 micrograms/ml). For 6 to 8% of the isolates, the minimum inhibitory concentrations were above 200 ...

  10. Comparative virulence genotyping and antimicrobial susceptibility profiling of environmental and clinical Salmonella enterica from Cochin, India

    Digital Repository Service at National Institute of Oceanography (India)

    Parvathi, A.; Vijayan, J.; Murali, G.; Chandran, P.

    . Newport revealed multiple drug resistance to ampicillin, amoxicillin/clavulanic acid, trimethorprim-sulfamethoxazole, chloramphenicol, tetracycline, cephalothin, and cephalexin. In comparison, S. Typhi were susceptible to all clinically relevant...

  11. High-throughput metal susceptibility testing of microbial biofilms

    Directory of Open Access Journals (Sweden)

    Turner Raymond J

    2005-10-01

    Full Text Available Abstract Background Microbial biofilms exist all over the natural world, a distribution that is paralleled by metal cations and oxyanions. Despite this reality, very few studies have examined how biofilms withstand exposure to these toxic compounds. This article describes a batch culture technique for biofilm and planktonic cell metal susceptibility testing using the MBEC assay. This device is compatible with standard 96-well microtiter plate technology. As part of this method, a two part, metal specific neutralization protocol is summarized. This procedure minimizes residual biological toxicity arising from the carry-over of metals from challenge to recovery media. Neutralization consists of treating cultures with a chemical compound known to react with or to chelate the metal. Treated cultures are plated onto rich agar to allow metal complexes to diffuse into the recovery medium while bacteria remain on top to recover. Two difficulties associated with metal susceptibility testing were the focus of two applications of this technique. First, assays were calibrated to allow comparisons of the susceptibility of different organisms to metals. Second, the effects of exposure time and growth medium composition on the susceptibility of E. coli JM109 biofilms to metals were investigated. Results This high-throughput method generated 96-statistically equivalent biofilms in a single device and thus allowed for comparative and combinatorial experiments of media, microbial strains, exposure times and metals. By adjusting growth conditions, it was possible to examine biofilms of different microorganisms that had similar cell densities. In one example, Pseudomonas aeruginosa ATCC 27853 was up to 80 times more resistant to heavy metalloid oxyanions than Escherichia coli TG1. Further, biofilms were up to 133 times more tolerant to tellurite (TeO32- than corresponding planktonic cultures. Regardless of the growth medium, the tolerance of biofilm and planktonic

  12. MICROBIOLOGICAL AND THEIR ANTIMICROBIAL SUSCEPTIBILITY PATTERN IN PATIENTS WITH CHRONIC DISCHARGING EAR DISEASE

    Directory of Open Access Journals (Sweden)

    Abhinav Paul

    2015-05-01

    Full Text Available AIM: Aim is to find out the bacteriological flora and their susceptibility pattern in patients with chronic discharging ear in tertiary care centre, Ranchi, Jharkhand. DESIGN: Prospective study . METHOD S : A total of 30 patients with unilateral or bilateral active chronic discharging ear patient attending OPD and Indoor, ENT Department, RIMS were included. RESULT: A total of 30 patients were studied with unilateral and bilateral discharging ear. The microbi ology of ear swab taken from 30 patients were evaluated and the most common pathogen isolated was Staphylococcus aureus (73.33% followed by Pseudomonas aeruginosa (20%, Coliforms (6.67%. Staphylococcus aureus were found to susceptible to levofloxacin (8 6.36%, gentamicin (86.36%, and ciprofloxacin (81.81% a nd pseudomonas aeruginosa were resistant to ciprofloxacin and cloxacillin and susceptible to amikacin (83.33%, lomefloxacin (66.67%, and azithromycin (50%. CONCLUSION: Staphylococcus aureus was t he most common pathogen isolated from ear swabs of patients with chronic discharging ear disease. This study determines the prevalent bacterial organism with antibiotic susceptibility to start empirical treatment and thus, to prevent the emergence of resis tant strain. KEYWORDS: C hronic otitis media, susceptibility, ear discharge, microbiology susceptibility.

  13. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

    Directory of Open Access Journals (Sweden)

    Débora Paula Ferreira

    2010-10-01

    Full Text Available Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110 and non-diarrheic (n=65 fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic, and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

  14. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of bacteroides fragilis group in diarrheic and non-diarrheic feces from brazilian infants.

    Science.gov (United States)

    Ferreira, Débora Paula; Silva, Vânia Lúcia; Guimarães, Danielle Aparecida; Coelho, Cíntia Marques; Zauli, Danielle Alves Gomes; Farias, Luiz Macêdo; Carvalho, Maria Auxiliadora Roque; Diniz, Claudio Galuppo

    2010-07-01

    Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic), and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children. PMID:24031535

  15. EUCAST technical note on isavuconazole breakpoints for Aspergillus, itraconazole breakpoints for Candida and updates for the antifungal susceptibility testing method documents.

    Science.gov (United States)

    Arendrup, M C; Meletiadis, J; Mouton, J W; Guinea, J; Cuenca-Estrella, M; Lagrou, K; Howard, S J

    2016-06-01

    The Subcommittee on Antifungal Susceptibility Testing (AFST) of the ESCMID European Committee for Antimicrobial Susceptibility Testing (EUCAST) has determined breakpoints for isavuconazole and Aspergillus and for itraconazole and Candida spp., released a new document summarizing existing and new minimum inhibitory concentration ranges for quality control strains and revised the method documents for yeast and mould susceptibility testing. This technical note is based on the EUCAST isavuconazole and itraconazole rationale documents, version 1.0 of the routine and extended internal quality control for antifungal susceptibility testing as recommended by EUCAST, and the E.Def 7.3, E.Def 9.2 and E.Def 9.3 method documents (http://www.eucast.org). PMID:26851656

  16. Improved Susceptibility Pattern of Antimicrobials Using Vital Energy Treatment on Shigella sonnei

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Complementary and alternative medicine (CAM) has become increasingly popular and reported for countless benefits in biomedical health care systems. The study assessed the potential impact of The Trivedi Effect® (biofield energy) on Shigella sonnei for changes in antimicrobial sensitivity, biochemical study, and biotype number using MicroScan Walk-Away® system. The cells were obtained from MicroBioLogics Inc., USA bearing the American Type Culture Collection (ATCC 9...

  17. A comparison of non-typhoidal Salmonella from humans and food animals using pulsed-field gel electrophoresis and antimicrobial susceptibility patterns

    Science.gov (United States)

    Salmonellosis is one of the most important foodborne diseases affecting humans. To characterize the relationship between Salmonella causing human infections and their food animal reservoirs, we compared pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility patterns of non-typhoida...

  18. Antimicrobial susceptibility and genetic characteristics of Neisseria gonorrhoeae isolates from Vietnam, 2011

    Directory of Open Access Journals (Sweden)

    Olsen Birgitta

    2013-01-01

    Full Text Available Abstract Background Antimicrobial resistance (AMR in Neisseria gonorrhoeae is a major public health concern worldwide. In Vietnam, knowledge regarding N. gonorrhoeae prevalence and AMR is limited, and data concerning genetic characteristics of N. gonorrhoeae is totally lacking. Herein, we investigated the phenotypic AMR (previous, current and possible future treatment options, genetic resistance determinants for extended-spectrum cephalosporins (ESCs, and genotypic distribution of N. gonorrhoeae isolated in 2011 in Hanoi, Vietnam. Methods N. gonorrhoeae isolates from Hanoi, Vietnam isolated in 2011 (n = 108 were examined using antibiograms (Etest for 10 antimicrobials, Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST, and sequencing of ESC resistance determinants (penA, mtrR and penB. Results The levels of in vitro resistance were as follows: ciprofloxacin 98%, tetracycline 82%, penicillin G 48%, azithromycin 11%, ceftriaxone 5%, cefixime 1%, and spectinomycin 0%. The MICs of gentamicin (0.023-6 mg/L, ertapenem (0.002-0.125 mg/L and solithromycin (penA mosaic alleles were found, however, 78% of the isolates contained an alteration of amino acid A501 (A501V (44% and A501T (34% in the encoded penicillin-binding protein 2. A single nucleotide (A deletion in the inverted repeat of the promoter region of the mtrR gene and amino acid alterations in MtrR was observed in 91% and 94% of the isolates, respectively. penB resistance determinants were detected in 87% of the isolates. Seventy-five different NG-MAST STs were identified, of which 59 STs have not been previously described. Conclusions In Vietnam, the highly diversified gonococcal population displayed high in vitro resistance to antimicrobials previously recommended for gonorrhoea treatment (with exception of spectinomycin, but resistance also to the currently recommended ESCs were found. Nevertheless, the MICs of three potential future treatment options were low. It is

  19. Bacteremic pneumococcal pneumonia: serotype distribution, antimicrobial susceptibility, severity scores, risk factors, and mortality in a single center in Chile

    Directory of Open Access Journals (Sweden)

    Alberto Fica

    2014-04-01

    Full Text Available AIMS: Bacteremic pneumococcal pneumonia (BPP is a severe condition. To evaluate seasonal distribution, mortality, serotype frequencies, antimicrobial susceptibility, and different severity scores among patients with BPP. PATIENTS AND METHODS: Patients were identified by laboratory data and restricted to adulthood. Standard methods were used for serotyping and antimicrobial susceptibility. Risk factors were analyzed by univariate and multivariate methods. Severity scores (APACHE II, CURB-65 and CAP PIRO were compared using ROC curves. RESULTS: Sixty events of community-acquired BPP occurred between 2005 and 2010. A seasonal pattern was detected. Mean age was 72.1 years old (81.4% >60 years. All had a predisposing factor. Previous influenza (3.3% or pneumococcal immunization (1.7% was infrequent. Admission to critical units was required by 51.7%. Twenty-two serotypes were identified among 59 strains. Only one strain had intermediate resistance to penicillin (1.7%. In-hospital mortality reached 33.3%. Multivariate analysis identified a CAP PIRO score>3 (OR 29.7; IC95 4.7-187, age >65 years (OR 42.1; IC95 2.2-796, and a platelet count<100,000/μL (OR 10.9; IC95 1.2-96 as significant independent factors associated with death. ROC curve analysis did not reveal statistical differences between the three severity scores to predict death (AUC 0.77-0.90. The prognostic yield for all of them was limited (Positive Likelihood Ratio: 1.5-3.8. CONCLUSIONS: BPP had a high case-fatality rate in this group of adult patients with no association to resistant isolates, and a low immunization record. Three independent factors were related to death and the prognostic yield of different severity scores was low.

  20. Isolation and speciation of Enterococci from various clinical samples and their antimicrobial susceptibility pattern with special reference to high level Aminoglycoside resistance

    Directory of Open Access Journals (Sweden)

    :Saroj Golia, Nirmala AR, Asha S Kamath B

    2014-07-01

    Full Text Available Background and Objectives: Enterococci are important nosocomial agents and strains resistant to penicillin and other antibiotics occur frequently. Enterococci are intrinsically resistant to cephalosporins and offer low level resistance to aminoglycosides. In penicillin sensitive strains, synergism occurs with combination treatment with penicillin and aminoglycoside. Serious infections caused by them are treated with penicillin and aminoglycoside combination. But the synergistic effect is lost, when the strain develops high level aminoglycoside resistance. The choice of drug for infections due to such strains is vancomycin. The present study was carried out to isolate and speciate Enterococci from various clinical samples, to know the susceptibility pattern of the isolates, to determine the High Level Aminoglycoside Resistance (HLAR among Enterococcal isolates. Methods: A total of One hundred Enterococcal species isolated from various clinical samples were identified by various biochemical reactions. Antimicrobial susceptibility testing and HLAR were determined by Kirby- Bauer disc diffusion method. Results: Out of 100 Enterococcal isolates, 59 were E. faecalis, 38 were E. faecium, 3 were other Enterococcal species. Among these 53 isolates showed High Level Aminoglycoside Resistance. Conclusion: Present study shows the presence of drug resistance to most of commonly used antibiotics and HLAR is also more in E.faecium compared to E.fecalis.

  1. Etiology and Antimicrobial Susceptibility of Bace­rial Septic Arthritis and Osteomyelitis

    Directory of Open Access Journals (Sweden)

    N Kalantari

    2007-09-01

    Full Text Available Background: To assess the distribution and resistance of the pathogens responsible for septic arthritis and osteomyelitis over a 10 years period in children admitted to Children's Medical Center Hospital, Tehran, Iran.Methods: Microbiologic and clinical presentation reports from 145 cases of septic arthritis and osteomyelitis from March 1995 to February 2005 were retrospectively reviewed. Results: Of 145 cases, 71(49% had positive culture: 71.8%(51/71 of organisms were isolated from synovial fluid alone, 8.4%(6/71 from blood culture alone and 19.7% (14/71 from both synovial fluids and blood cultures. Staphylococcus aureus was the most common pathogen isolated, making up 60.5% of all positive cultures, followed by Klebsiella spp. (14% and coagulase-negative staphylococci (8.4%. Thirty eight percent of S. aureus and 84% of coagulase-negative staphylo­cocci isolates were resistant to cloxacillin. All isolates of S. aureus were susceptible to clindamycin and also, 89% were susceptible to vancomycin. Among Klebsiella spp., amikacin was shown to be very effective, with susceptibility rates of 100%. Haemophilus influenzae was identified in only 2% of all patients.Conclusion: The present study highlights the importance of characterizing the etiology and antibiotic susceptibility of organ­isms causing septic arthritis or osteomylitis in children.

  2. Serogroups and antimicrobial susceptibility among Escherichia coli isolated from farmed mink (Mustela vison Schreiber) in Denmark

    DEFF Research Database (Denmark)

    Vulfson, L.; Pedersen, Karl; Chriel, M.;

    2001-01-01

    most frequent being O2 (11.0%). O78 (11.0%), O153 (7.1%). O25 (5.7%). O6 (4.8%). and O15 (4.8%). but diarrhoea was not associated with specific serogroups. All isolates were sensitive to enrofloxacin, neomycin, gentamicin and colistin. In contrast, considerable variations in susceptibility were found...

  3. Performance of the microscopic observation drug susceptibility assay in pyrazinamide susceptibility testing for Mycobacterium tuberculosis

    Institute of Scientific and Technical Information of China (English)

    HUANG Zi-kun; LUO Qing; JIANG Bi-xia; LI Wei-ting; XU Xiao-meng; XIONG Guo-liang; LI Jun-ming

    2013-01-01

    Background Drug susceptibility assay is very important in tuberculosis therapy.Pyrazinamide is a first line antituberculosis drug and diagnosis of its resistance in Mycobacterium tuberculosis (M.tuberculosis) is difficult and time consuming by conventional methods.In this study,we aimed to evaluate the performance of the microscopic observation drug susceptibility (MODS) assay in the detection of pyrazinamide resistance in M.tuberculosis relative to the conventional Wayne assay and Lowenstein-Jensen (L J) proportion method.Methods M.tuberculosis clinical isolates (n=132) were tested by the MODS and the Wayne assay:the results were compared with those obtained by the LJ proportion method.Mutations in the gene were identified by direct sequencing of the pncA genes of all isolates in which pyrazinamide resistance was detected by any of the three methods.Results Compared to the LJ results,the sensitivity and specificity of the MODS assay were 97.8% and 96.5% respectively; the sensitivity and specificity of the Wayne assay were 87.0% and 97.7% respectively.Mutations in the pncA gene were found in 41 of 46 strains that were pyrazinamide resistant (3 tests),in 1 of the 4 strains (LJ only),in 42 of 48 strains (at least 1 test),but no mutations in 1 strain sensitive according to the MODS assay only.The MODS assay,Wayne assay and LJ proportion method provided results in a median time of 6,7 and 26 days respectively.Conclusions MODS assay offers a rapid,simple and reliable method for the detection of pyrazinamide resistance in M.tuberculosis and is an optimal alternative method in resource limited countries.

  4. [Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1996), III. Secular changes in susceptibility].

    Science.gov (United States)

    Kumamoto, Y; Tsukamoto, T; Hirose, T; Yokoo, A; Shigeta, S; Takahashi, T; Shiraiwa, Y; Ogiwara, M; Yoshida, H; Imafuku, Y; Murai, M; Watanabe, K; Uchida, H; Kobayashi, Y; Matsuda, S; Fujime, M; Fujita, K; Igari, J; Oguri, T; Yamaguchi, K; Matsumoto, T; Kashitani, F; Kaku, M; Ooe, H; Mochida, C

    1998-03-01

    Susceptibilities to various antimicrobial agents were examined for Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp., and Pseudomonas aeruginosa that were isolated from patients with urinary tract infections (UTIs) in 10 hospitals during June 1996 to May 1997, and the results were compared with those obtained during the same period in earlier years. 1. E. faecalis Among E. faecalis strains, those with high susceptibilities to ampicillin and minocycline appeared to have decreased in the latest study period. 2. S. aureus To almost antimicrobial agents, S. aureus isolated from uncomplicated UTIs showed low susceptibilities. But the MIC50s of those agents for S. aureus from complicated UTIs have changed better state. Particularly, the MIC50s of imipenem and clindamycin were 0.125 microgram/ml or below in the latest period for the first time in our history. 3. E. coli The susceptibilities to piperacillin and quinolones of E. coli isolated from uncomplicated UTIs were better than those isolated from complicated UTIs. 4. Klebsiella spp. The susceptibilities to almost antimicrobial agents of Klebsiella spp. have been better during the latest period, compared to those during period of 1995-1996, but to ofloxacin and ciprofloxacin have appeared to have been lower. 5. P. aeruginosa The susceptibilities to quinolones of P. aeruginosa have been better during the latest period compared those during periods of 1995-1996. But, the susceptibilities to cefozopran, carbapenems and monobactams of P. aeruginosa isolated from complicated UTIs appeared to have been lower. These susceptibility changes should be utilized in determining clinical treatments. PMID:9597551

  5. Evaluation of antimicrobial effectiveness of ophthalmic drops according to the pharmacopeial tests criteria

    OpenAIRE

    N Samadi; Tarighi, P.; M.R Fazeli; H Mehrgan

    2009-01-01

    ABSTRACT Background: In this study antimicrobial effectiveness test was performed on eye-drops which had high microbial contaminations in hospital practice to find out whether their antimicrobial efficacies affect the magnitude of microbial contamination during their uses. Materials and Methods: Artificial tear, atropine sulfate, betamethasone, homatropine hydrobromide, phenylephrine hydrochloride, phenylephrine zinc, pilocarpine hydrochloride, tetracaine hydrochloride and tropicamide eye-dro...

  6. Protocols to test the activity of antimicrobial peptides against the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Khilnani, Jasmin C; Wing, Helen J

    2015-10-01

    Paenibacillus larvae is the causal agent of the honey bee disease American Foulbrood. Two enhanced protocols that allow the activity of antimicrobial peptides to be tested against P. larvae are presented. Proof of principle experiments demonstrate that the honey bee antimicrobial peptide defensin 1 is active in both assays. PMID:26210039

  7. In vitro susceptibility testing of Fonsecaea pedrosoi to antifungals

    Directory of Open Access Journals (Sweden)

    BEDOUT Catalina de

    1997-01-01

    Full Text Available Based on the difficulties experienced in the treatment of chromoblastomycosis, 12 primary human isolates of F. pedrosoi, were tested for their in vitro susceptibility to various antimycotics. We adapted the recommendations of the NCCLS for yeasts and followed the indications for mold testing from other authors in order to determine their MIC?s and the MLC?s. It was found that a significant proportion of the isolates were resistant to 3 of the 4 antimycotics tested, as revealed by high MIC values, as follows: 33% were resistant to amphotericin B (AMB, 58.3% to 5 fluocytosine (5 FC and 66.7% to fluconazole (FLU. Contrarywise, none of the isolates proved resistant to itraconazole (ITZ. Determination of the MLC?s revealed that a larger proportion of the isolates were not killed by AMB, 5 FC (91.7%, FLU (100% or even, ITZ (41.7%. These data indicate that it would be desirable to determine the susceptibility of F. pedrosoi before initiating therapy, in order to choose the more effective antifungal and avoid clinical failure

  8. Susceptibility of anaerobic bacteria to metronidazole, ornidazole, and tinidazole and routine susceptibility testing by standardized methods.

    Science.gov (United States)

    Wust, J

    1977-04-01

    A total of 114 strains of anaerobic bacteria were examined for their susceptibility to metronidazole, ornidazole, and tinidazole by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration in different media. All strains, with the exception of the isolates of Propionibacterium acnes, were inhibited by 3.1 mug each and killed by 6.3 mug each of all three nitroimidazole compounds per ml. No significant differences in MIC values were found among metronidazole, ornidazole, and tinidazole. Only minor differences were detected by comparing MIC values obtained in brain heart infusion agar with and without sheep blood, brucella agar, and Mueller-Hinton agar (both containing blood). When the strains were tested by the modified broth-disk method proposed by the Anaerobe Laboratory of the Virginia Polytechnic Institute (VPI), there was good correlation with the MIC values (97.4% agreement for metronidazole and 94.7% for ornidazole and tinidazole). For routine testing, use of a 30-mug-class disk of either nitroimidazole derivative is proposed for the broth-disk method, resulting in a final concentration of 6 mug/ml in the test tubes, a concentration easily attainable in body fluids. In contrast to the broth-disk method, there was very poor correlation between inhibition zone diameters by the standardized VPI agar diffusion test and MIC values. PMID:856015

  9. Susceptibility

    Czech Academy of Sciences Publication Activity Database

    Petrovský, Eduard

    Dordrecht: Springer, 2007 - (Gubbins, D.; Herrero-Bervera, E.), s. 931-933. (Encyclopedia of Earth sciences series). ISBN 978-1-4020-3992-8 Institutional research plan: CEZ:AV0Z30120515 Keywords : magnetic susceptibility * magnetic field * magnetization curve Subject RIV: DE - Earth Magnetism, Geodesy, Geography

  10. Induction of In Vitro Resistance to Penicillin in Viridans Group Streptococci and Its Effect on Susceptibility Pattern of Other Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Shree V. Dhotre

    2016-04-01

    Full Text Available Background: The development of resistance to penicillin in Viridans Group Streptococci (VGS during therapy has been reported. However, the in vitro development of resistance to penicillin or other antimicrobial agents in VGS is mostly overlooked and rarely reported. Aim & Objectives: To induce in vitro resistance to penicillin in VGS and to study its effect on susceptibility pattern of other structurally related (Beta–lactams and unrelated antimicrobial agents. Material and Methods: Four isolates of VGS susceptible to all antimicrobial agents were manipulated in vitro to induce resistance to penicillin by sequential exposure to increasing concentrations of penicillin. Results: Increase in MIC values of penicillin from 0.06-0.12 µg/ml to 2-32 µg/ml was observed indicating development of resistance to penicillin. A significant increase in Minimum Inhibitory Concentration (MIC values of ampicillin and slight increase in MIC values of other antimicrobial agents in some isolates was also noted. Conclusions: Exposure to increasing concentrations of penicillin can promote the development of resistance to penicillin and cross-resistance to other antimicrobial agents suggesting its mutagenic role.

  11. Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from patients attending a public referral center for sexually transmitted diseases in Belo Horizonte, State of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Ligia Maria Bedeschi Costa

    2013-06-01

    Full Text Available Introduction The aim of this study was to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates obtained from patients attending a public referral center for sexually transmitted diseases and specialized care services (STD/SCS in Belo Horizonte, Brazil. Methods Between March 2011 and February 2012, 201 specimens of Neisseria gonorrhoeae were consecutively obtained from men with symptoms of urethritis and women with symptons of cervicitis or were obtained during their initial consultation. The strains were tested using the disk diffusion method, and the minimum inhibitory concentrations of azithromycin, cefixime, ceftriaxone, ciprofloxacin, chloramphenicol, penicillin, tetracycline and spectinomycin were determined using the E-test. Results The specimens were 100% sensitive to cefixime, ceftriaxone and spectinomycin and exhibited resistances of 4.5% (9/201, 21.4% (43/201, 11.9% (24/201, 22.4% (45/201 and 32.3% (65/201 to azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. Intermediate sensitivities of 17.9% (36/201, 4% (8/201, 16.9% (34/201, 71.1% (143/201 and 22.9% (46/201 were observed for azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. The specimens had plasmid-mediated resistance to penicillin PPNG 14.5% (29/201 and tetracycline TRNG 11.5% (23/201. Conclusions The high percentage of detected resistance to penicillin, tetracycline, chloramphenicol and ciprofloxacin indicates that these antibiotics are not appropriate for gonorrhea treatment at the Health Clinic and possibly in Belo Horizonte. The resistance and intermediate sensitivity of these isolates indicates that caution is recommended in the use of azithromycin and emphasizes the need to establish mechanisms for the surveillance of antimicrobial resistance for the effective control of gonorrhea.

  12. Disk diffusion susceptibility testing of the Bacteroides fragilis group.

    Science.gov (United States)

    Horn, R; Bourgault, A M; Lamothe, F

    1987-10-01

    The susceptibilities of 225 isolates of the Bacteroides fragilis group to six antibiotics were determined by a new disk diffusion test in Wilkins-Chalgren agar and by the standard agar dilution method. For disk diffusion, the bacteria were directly suspended in saline and immediately swabbed onto 15-cm agar plates. Disks of cefoxitin (30 micrograms), chloramphenicol (30 micrograms), clindamycin (2 micrograms), moxalactam (30 micrograms), imipenem (10 micrograms), and ticarcillin (75 micrograms) were applied, and the plates were incubated at 37 degrees C in an anaerobic atmosphere. Zone sizes were measured at 24 h. The results of disk diffusion and agar dilution were compared by regression analysis by the method of least squares and by the error rate-bounded method. Zones were easily measured for 216 strains (96%). The correlation between the MICs and diameters of inhibition for cefoxitin, clindamycin, moxalactam, and ticarcillin was generally good. A correlation could not be established for chloramphenicol and imipenem, as there were too few resistant strains. With the recommended resistance breakpoints, the following susceptible and resistant zone diameter breakpoints could be established: cefoxitin, less than or equal to 19 and greater than or equal to 21 mm; clindamycin, less than or equal to 14 and greater than or equal to 18 mm; moxalactam, less than or equal to 21 and greater than or equal to 25 mm; and ticarcillin, less than or equal to 15 and greater than or equal to 16 mm. By applying these zone criteria, the percentage of false-susceptible strains was less than 1% and of false-resistant strains was less than 4% for the drugs tested. PMID:3481247

  13. OCIMUM BASILICUM AND MENTHA PIPERITA ESSENTIAL OILS INFLUENCE THE ANTIMICROBIAL SUSCEPTIBILITY OF STAPHYLOCOCCUS AUREUS STRAINS

    OpenAIRE

    Dan Mihaiescu; Crina Saviuc; Ioana Marinaş; Carmen Mariana Chifiriuc; Alexandru Mihai Grumezescu; Veronica Lazǎr

    2012-01-01

    Essential oils extracted by microwave assisted hydrodistillation technique from Ocinum basilicum and Mentha piperita were characterized by GC-MS. An adapted diffusion method was used in order to assess the potentiator effect of the essential oils on the susceptibility of Staphylococcus aureus clinical and reference strains to some of the currently used antibiotics, i.e. clindamycin, ciprofloxacin, tetracycline, gentamicin, penicillin and erythromycin.. The Ocimum basilicum and Mentha piperit...

  14. Molecular Characterization and Antimicrobial Susceptibility of Nasal Staphylococcus aureus Isolates from a Chinese Medical College Campus

    OpenAIRE

    DU, JIMEI; Chen, Chun; Ding, Baixing; Tu, Jinjing; Qin, Zhiqiang; Parsons, Chris; Salgado, Cassandra; Cai, Qiangjun; SONG, Yulong; Bao, Qiyu; Zhang, Liming; Pan, Jingye; Wang, LiangXing; Yu, Fangyou

    2011-01-01

    Staphylococcus aureus colonization and infection occur more commonly among persons living or working in crowded conditions, but characterization of S. aureus colonization within medical communities in China is lacking. A total of 144 (15.4%, 144/935) S. aureus isolates, including 28 (3.0%, 28/935) MRSA isolates, were recovered from the nares of 935 healthy human volunteers residing on a Chinese medical college campus. All S. aureus isolates were susceptible to vancomycin, quinupristin/dalfopr...

  15. Trends in antimicrobial susceptibility of Salmonella Typhi from North India (2001-2012)

    OpenAIRE

    Singhal, L.; Gupta, P. K.; Kale, P.; V Gautam; Ray, P.

    2014-01-01

    Purpose: Enteric fever is endemic in India with Salmonella Typhi being the major causative agent. Antibiotic therapy constitutes the mainstay of management. The present study was undertaken to find the susceptibility profile of Salmonella enterica var Typhi (S. Typhi) blood isolates in a tertiary care hospital between January 2001 and December 2012. Materials and Methods: A retrospective analysis of laboratory records was carried out. Conventional blood culture method was used until 2009; fro...

  16. Antimicrobial Susceptibility and Molecular Mechanisms of Fosfomycin Resistance in Clinical Escherichia coli Isolates in Mainland China.

    Directory of Open Access Journals (Sweden)

    Ya Li

    Full Text Available Escherichia coli is one of the most common pathogens in nosocomial and community-acquired infections in humans. Fosfomycin is a broad-spectrum antibiotic which inhibits peptidoglycan synthesis responsible for bacterial cell wall formation. Although low, the exact E. coli susceptibility to fosfomycin as well as the mechanisms of resistance in the population from Mainland China are mostly unknown. 1109 non-duplicate clinical E. coli strains isolated from urine, sputum, blood and pus samples in 20 widely dispersed tertiary hospitals from Mainland China were collected from July 2009 to June 2010, followed by determination of minimum inhibitory concentrations of fosfomycin. Detection of the murA, glpT, uhpT, fosA, fosA3 and fosC genes was performed in fosfomycin non-susceptible E. coli strains and conjugation experiments were employed to determine the mobility of fosA3 gene. In this study, 7.8% (86/1109 E. coli strains were fosfomycin non-susceptible. Amino acid substitutions in GlpT and MurA were found in six and four E.coli strains, respectively, while the uhpT gene was absent in eighteen E.coli strains. Twenty-nine isolates carried the transferable plasmid with the fosA3 gene at high frequencies of around 10(-6 to 10(-7 per donor cell in broth mating. The majority of isolates were susceptible to fosfomycin, showing that the drug is still viable in clinical applications. Also, the main mechanism of E. coli resistance in Mainland China was found to be due to the presence of the fosA3 gene.

  17. Antimicrobial susceptibility patterns of enterobacteriaceae isolated from HIV-infected patients in Kinshasa

    OpenAIRE

    Iyamba, Jean-Marie Liesse; Wambale, José Mulwahali; Takaisi-Kikuni, Ntondo za Balega

    2014-01-01

    Introduction People infected by Human Immunodeficiency Virus (HIV) are susceptible to develop severe bacterial infections. We set out to determine the frequency and the sensitivity to antibiotics of enterobaceriaceae isolated from urine and feces of HIV-infected persons. Methods Urine and feces samples were collected from HIV-infected patients of the Centre de Traitement Ambulatoire de Kabinda (CTA/Kabinda, Kinshasa) and analyzed at the Reference National Laboratory for HIV/AIDS and Sexually ...

  18. Lyme Borreliosis: is there a preexisting (natural) variation in antimicrobial susceptibility among Borrelia burgdorferi strains?

    Science.gov (United States)

    Hodzic, Emir

    2015-01-01

    The development of antibiotics changed the world of medicine and has saved countless human and animal lives. Bacterial resistance/tolerance to antibiotics have spread silently across the world and has emerged as a major public health concern. The recent emergence of pan-resistant bacteria can overcome virtually any antibiotic and poses a major problem for their successful control. Selection for antibiotic resistance may take place where an antibiotic is present in the skin, gut, and other tissues of humans and animals and in the environment. Borrelia burgdorferi, the etiological agents of Lyme borreliosis, evades host immunity and establishes persistent infections in its mammalian hosts. The persistent infection poses a challenge to the effective antibiotic treatment, as demonstrated in various animal models. An increasingly heterogeneous subpopulation of replicatively attenuated spirochetes arises following treatment, and these persistent antimicrobial tolerant/resistant spirochetes are non-cultivable. The non-cultivable spirochetes resurge in multiple tissues at 12 months after treatment, with B. burgdorferi-specific DNA copy levels nearly equivalent to those found in shame-treated experimental animals. These attenuated spirochetes remain viable, but divide slowly, thereby being tolerant to antibiotics. Despite the continued non-cultivable state, RNA transcription of multiple B. burgdorferi genes was detected in host tissues, spirochetes were acquired by xenodiagnostic ticks, and spirochetal forms could be visualized within ticks and mouse tissues. A number of host cytokines were up- or down-regulated in tissues of both shame- and antibiotic-treated mice in the absence of histopathology, indicating a lack of host response to the presence of antimicrobial tolerant/resistant spirochetes. PMID:26295288

  19. Testing methods for antimicrobial activity of TiO2 photocatalyst

    Directory of Open Access Journals (Sweden)

    Markov Siniša L.

    2014-01-01

    Full Text Available In recent years, a lot of commercial TiO2 photocatalyst products have been developed and extensively studied for prospective and safe antimicrobial application in daily life, medicine, laboratories, food and pharmaceutical industry, waste water treatments and in development of new self-cleaning and antimicrobial materials, surfaces and paints. This paper reviews the studies published worldwide on killing microorganisms, methods for testing the antimicrobial activity, light sources and intensities, as well as calculation methods usually used when evaluating the antimicrobial properties of the TiO2-based products. Additionally, some strengths and weaknesses of the available methods for testing the antimicrobial activity of TiO2 photocatalyst products have been pointed out.[Projekat Ministarstva nauke Republike Srbije, br. III45008

  20. Prevalence of community acquired urinary tract infections in silchar medical college, Assam, India and its antimicrobial susceptibility profile

    Directory of Open Access Journals (Sweden)

    Indu Sharma

    2012-01-01

    Full Text Available Background: This study was conducted to know the rate of prevalence of community acquired UTI infections in both males and females, Assam, North-East India. Materials and Methods: A 50 μl of urine sample from each of the subjects was streaked on cystine lactose electrolyte-deficient agar medium. The plates were incubated overnight at 37°C. Pure, isolated colonies of each type was separately cultured and characterized. The susceptibility of the clinical isolates to routinely prescribed antibiotics in the hospital was performed against various antibiotics. Results: Of the total 40 patients, 26 positive samples were obtained of which 19 females (73.07% and 7 male (26.92% patients were shown to be urine culture positive. The most commonly isolated bacterium was Escherichia coli with a frequency rate of (33.3% followed by Staphyloccous aureus (22.2%, Klebsiella pnemoniae (11.1%, coagulase negative Staphylococcus (CoNS (7.4%, Pseudomonas sp. (7.4%, Proteus myxofaciens (3.7%, Proteus mirabilis (3.7%, Edwardsiella tarda (3.7%, Morganella morganii (3.7%, and Citrobacter fruendii (3.7%. Analysis of the samples showed that UTI was more common in females of younger age group as compared with males. It was also observed that the patients responded effectively to imepenem (IE, cepefime, amikacin, norfloxacin, and co-trimoxazole antimicrobial agents against Gram-negative bacilli. Furthermore, the most effective antibiotics against Gram-positive cocci was found to be ampicillin, ciprofloxacin, IE, and penicillin G (benzyl penicillin. Conclusions: Antibiotics have been in use for a long period and more often the misuse of antimicrobial drugs has today led to a general rise in the emergence of resistant bacteria.

  1. Comparative in vitro activities of twelve antimicrobial agents against Campylobacter species.

    OpenAIRE

    Fliegelman, R M; Petrak, R M; Goodman, L. J.; Segreti, J; Trenholme, G M; Kaplan, R L

    1985-01-01

    The in vitro susceptibility of 27 Campylobacter jejuni, 31 Campylobacter coli, and 30 Campylobacter fetus subsp. fetus strains to 12 antimicrobial agents was determined. Ciprofloxacin, a new quinoline derivative, was the most active agent tested. Antimicrobial susceptibility differed among the three species tested.

  2. Drug susceptibility testing of clinical isolates of streptococci and enterococci by the Phoenix automated microbiology system

    Directory of Open Access Journals (Sweden)

    Sokeng Gertrude

    2007-05-01

    Full Text Available Abstract Background Drug resistance is an emerging problem among streptococcal and enterococcal species. Automated diagnostic systems for species identification and antimicrobial susceptibility testing (AST have become recently available. We evaluated drug susceptibility of clinical isolates of streptococci and enterococci using the recent Phoenix system (BD, Sparks, MD. Diagnostic tools included the new SMIC/ID-2 panel for streptococci, and the PMIC/ID-14 for enterococci. Two-hundred and fifty isolates have been investigated: β-hemolytic streptococci (n = 65, Streptococcus pneumoniae (n = 50, viridans group streptococci (n = 32, Enterococcus faecium (n = 40, Enterococcus faecalis (n = 43, other catalase-negative cocci (n = 20. When needed, species ID was determined using molecular methods. Test bacterial strains were chosen among those carrying clinically-relevant resistance determinants (penicillin, macrolides, fluoroquinolones, glycopeptides. AST results of the Phoenix system were compared to minimal inhibitory concentration (MIC values measured by the Etest method (AB Biodisk, Solna, Sweden. Results Streptococci: essential agreement (EA and categorical agreement (CA were 91.9% and 98.8%, respectively. Major (ME and minor errors (mE accounted for 0.1% and 1.1% of isolates, respectively. No very major errors (VME were produced. Enterococci: EA was 97%, CA 96%. Small numbers of VME (0.9%, ME (1.4% and mE (2.8% were obtained. Overall, EA and CA rates for most drugs were above 90% for both genera. A few VME were found: a teicoplanin and high-level streptomycin for E. faecalis, b high-level gentamicin for E. faecium. The mean time to results (± SD was 11.8 ± 0.9 h, with minor differences between streptococci and enterococci. Conclusion The Phoenix system emerged as an effective tool for quantitative AST. Panels based on dilution tests provided rapid and accurate MIC values with regard to clinically-relevant streptococcal and enterococcal

  3. Etiology and antimicrobial susceptibility of udder pathogens from cases of subclinical mastitis in dairy cows in Sweden

    Directory of Open Access Journals (Sweden)

    Nyman Ann-Kristin J

    2011-06-01

    Full Text Available Abstract Background A nationwide survey on the microbial etiology of cases of subclinical mastitis in dairy cows was carried out on dairy farms in Sweden. The aim was to investigate the microbial panorama and the occurrence of antimicrobial resistance. Moreover, differences between newly infected cows and chronically infected cows were investigated. Methods In total, 583 quarter milk samples were collected from 583 dairy cows at 226 dairy farms from February 2008 to February 2009. The quarter milk samples were bacteriological investigated and scored using the California Mastitis Test. Staphylococci were tested for betalactamase production and presence of resistance was evaluated in all specific udder pathogens. Differences between newly infected cows and chronically infected cows were statistically investigated using logistic regression analysis. Results The most common isolates of 590 bacteriological diagnoses were Staphylococcus (S aureus (19% and coagulase-negative staphylococci (CNS; 16% followed by Streptococcus (Str dysgalactiae (9%, Str. uberis (8%, Escherichia (E. coli (2.9%, and Streptococcus spp. (1.9%. Samples with no growth or contamination constituted 22% and 18% of the diagnoses, respectively. The distribution of the most commonly isolated bacteria considering only bacteriological positive samples were: S. aureus - 31%, CNS - 27%, Str. dysgalactiae - 15%, Str. uberis - 14%, E. coli - 4.8%, and Streptococcus spp. - 3.1%. There was an increased risk of finding S. aureus, Str. uberis or Str. dysgalactiae in milk samples from chronically infected cows compared to findings in milk samples from newly infected cows. Four percent of the S. aureus isolates and 35% of the CNS isolates were resistant to penicillin G. Overall, resistance to other antimicrobials than penicillin G was uncommon. Conclusions Staphylococcus aureus and CNS were the most frequently isolated pathogens and resistance to antimicrobials was rare.

  4. Etiology and antimicrobial susceptibility of udder pathogens from cases of subclinical mastitis in dairy cows in Sweden

    Science.gov (United States)

    2011-01-01

    Background A nationwide survey on the microbial etiology of cases of subclinical mastitis in dairy cows was carried out on dairy farms in Sweden. The aim was to investigate the microbial panorama and the occurrence of antimicrobial resistance. Moreover, differences between newly infected cows and chronically infected cows were investigated. Methods In total, 583 quarter milk samples were collected from 583 dairy cows at 226 dairy farms from February 2008 to February 2009. The quarter milk samples were bacteriological investigated and scored using the California Mastitis Test. Staphylococci were tested for betalactamase production and presence of resistance was evaluated in all specific udder pathogens. Differences between newly infected cows and chronically infected cows were statistically investigated using logistic regression analysis. Results The most common isolates of 590 bacteriological diagnoses were Staphylococcus (S) aureus (19%) and coagulase-negative staphylococci (CNS; 16%) followed by Streptococcus (Str) dysgalactiae (9%), Str. uberis (8%), Escherichia (E.) coli (2.9%), and Streptococcus spp. (1.9%). Samples with no growth or contamination constituted 22% and 18% of the diagnoses, respectively. The distribution of the most commonly isolated bacteria considering only bacteriological positive samples were: S. aureus - 31%, CNS - 27%, Str. dysgalactiae - 15%, Str. uberis - 14%, E. coli - 4.8%, and Streptococcus spp. - 3.1%. There was an increased risk of finding S. aureus, Str. uberis or Str. dysgalactiae in milk samples from chronically infected cows compared to findings in milk samples from newly infected cows. Four percent of the S. aureus isolates and 35% of the CNS isolates were resistant to penicillin G. Overall, resistance to other antimicrobials than penicillin G was uncommon. Conclusions Staphylococcus aureus and CNS were the most frequently isolated pathogens and resistance to antimicrobials was rare. PMID:21649936

  5. Antimicrobial Susceptibility of Escherichia coli Strains Isolated from Alouatta spp. Feces to Essential Oils

    Directory of Open Access Journals (Sweden)

    Valéria Maria Lara

    2016-01-01

    Full Text Available This study evaluated the in vitro antibacterial activity of essential oils from Lippia graveolens (Mexican oregano, Origanum vulgaris (oregano, Thymus vulgaris (thyme, Rosmarinus officinalis (rosemary, Cymbopogon nardus (citronella, Cymbopogon citratus (lemongrass, and Eucalyptus citriodora (eucalyptus against Escherichia coli (n=22 strains isolated from Alouatta spp. feces. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL−1; MBC mean = 2618 μg mL−1, thyme (MIC mean = 2618 μg mL−1; MBC mean = 2909 μg mL−1, and oregano (MIC mean = 3418 μg mL−1; MBC mean = 4800 μg mL−1 showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL−1. Our results confirm the antimicrobial potential of some essential oils, which deserve further research.

  6. Antimicrobial Susceptibility of Escherichia coli Strains Isolated from Alouatta spp. Feces to Essential Oils

    Science.gov (United States)

    Carregaro, Adriano Bonfim; Santurio, Deise Flores; de Sá, Mariangela Facco; Santurio, Janio Moraes; Alves, Sydney Hartz

    2016-01-01

    This study evaluated the in vitro antibacterial activity of essential oils from Lippia graveolens (Mexican oregano), Origanum vulgaris (oregano), Thymus vulgaris (thyme), Rosmarinus officinalis (rosemary), Cymbopogon nardus (citronella), Cymbopogon citratus (lemongrass), and Eucalyptus citriodora (eucalyptus) against Escherichia coli (n = 22) strains isolated from Alouatta spp. feces. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL−1; MBC mean = 2618 μg mL−1), thyme (MIC mean = 2618 μg mL−1; MBC mean = 2909 μg mL−1), and oregano (MIC mean = 3418 μg mL−1; MBC mean = 4800 μg mL−1) showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL−1. Our results confirm the antimicrobial potential of some essential oils, which deserve further research. PMID:27313638

  7. Antimicrobial Susceptibility of Escherichia coli Strains Isolated from Alouatta spp. Feces to Essential Oils.

    Science.gov (United States)

    Lara, Valéria Maria; Carregaro, Adriano Bonfim; Santurio, Deise Flores; de Sá, Mariangela Facco; Santurio, Janio Moraes; Alves, Sydney Hartz

    2016-01-01

    This study evaluated the in vitro antibacterial activity of essential oils from Lippia graveolens (Mexican oregano), Origanum vulgaris (oregano), Thymus vulgaris (thyme), Rosmarinus officinalis (rosemary), Cymbopogon nardus (citronella), Cymbopogon citratus (lemongrass), and Eucalyptus citriodora (eucalyptus) against Escherichia coli (n = 22) strains isolated from Alouatta spp. feces. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL(-1); MBC mean = 2618 μg mL(-1)), thyme (MIC mean = 2618 μg mL(-1); MBC mean = 2909 μg mL(-1)), and oregano (MIC mean = 3418 μg mL(-1); MBC mean = 4800 μg mL(-1)) showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL(-1). Our results confirm the antimicrobial potential of some essential oils, which deserve further research. PMID:27313638

  8. Isolation and Identification of Pathogenic Gram-Positive Bacteria from Egg Shell of Hen and to See Their Antimicrobial Susceptibility Pattern

    Directory of Open Access Journals (Sweden)

    Jannatul Fardows

    2016-01-01

    Full Text Available Background: Food-borne disease is a major public health problem affecting developed as well as developing countries. Inaccurately treated eggs can be one of its causes. So we designed this study to observe the possibility of transmission of pathogenic Gram-positive bacteria from market eggs to the community. Objectives: To identify different Gram-positive bacteria in eggs and to observe their antimicrobial susceptibility. Materials and Methods: This observational study was conducted in the department of Microbiology, Dhaka Medical College, Dhaka. Shells of 150 eggs collected from different markets of Dhaka city were tested. Bacteria were isolated and identified by culture and relevant biochemical tests. Results: Out of 150 egg shells, 120 (80% yielded growth of different bacteria. Of them, Staphylococcus spp. were 80 (66.67%, Streptococcus spp. 8 (6.67%, Bacillus subtilis 20 (16.67% and Bacillus cereus 12 (10%. Out of 80 Staphylococcus spp., 30 (25% were Staphylococcus aureus and 50 (41.67% were Staphylococcus saprophyticus. Most of the Gram-positive bacteria were sensitive to ciprofloxacin, ceftriaxone and imipenem. No MRSA and VRSA were found. Conclusion: It can be concluded from this study that Gram-positive bacteria from market eggs may be an important source of infection to the community.

  9. Static NLO susceptibilities testing approximation schemes against exact results

    CERN Document Server

    Del Freo, L; Painelli, A; Freo, Luca Del; Terenziani, Francesca; Painelli, Anna

    2001-01-01

    The reliability of the approximations commonly adopted in the calculation of static optical (hyper)polarizabilities is tested against exact results obtained for an interesting toy-model. The model accounts for the principal features of typical nonlinear organic materials with mobile electrons strongly coupled to molecular vibrations. The approximations introduced in sum over states and finite field schemes are analyzed in detail. Both the Born-Oppenheimer and the clamped nucleus approximations turn out to be safe for molecules, whereas for donor-acceptor charge transfer complexes deviations from adiabaticity are expected. In the regime of low vibrational frequency, static susceptibilities are strongly dominated by the successive derivatives of the potential energy and large vibrational contributions to hyperpolarizabilities are found. In this regime anharmonic corrections to hyperpolarizabilities are very large, and the harmonic approximation, exact for the linear polarizability, turns out totally inadequate ...

  10. Identification and antimicrobial susceptibility patterns of Staphylococcus spp. isolated from canine chronic otitis externa

    Directory of Open Access Journals (Sweden)

    Silva N.

    2001-01-01

    Full Text Available Swab samples obtained from 96 dogs with chronic otitis externa were cultured for the isolation of Staphylococcus species. Of 57 staphylococcal strains, 41 (72% were coagulase-negative (CNS. The identification of staphylococci strains was made by standard procedures for the routine identification of staphylococci in clinical practice. S. sciuri was the most frequent species isolated (22.8% from chronic otitis externa in dogs followed by S. intermedius (12.3%, S. auricularis (10.5% and S. aureus (8.8%. Three (5.2% CNS strains could not be identified. Bacterial isolates were susceptible to enrofloxacin, gentamicin, cephalothin, chloramphenicol and neomycin. Resistance was most common to penicillin G, oxacillin and ampicillin.

  11. Longitudinal study of Clostridium difficile and antimicrobial susceptibility of Escherichia coli in healthy horses in a community setting

    DEFF Research Database (Denmark)

    Schoster, Angelika; Staempfli, H. R.; Arroyo, L. G.;

    2012-01-01

    were to investigate and molecularly characterize isolates of Clostridium difficile, Clostridium perfringens and Salmonella, collected sequentially over a one year period, and to determine the antibiotic susceptibility profile for E. coli. Fecal samples were collected monthly from 25 adult horses for...... one year. Selective cultures were performed for all above bacteria. C. difficile isolates were characterized via PCR toxin gene profiling and ribotyping. Broth microdilution was performed to assess antimicrobial susceptibility profiles of E. coli. Toxigenic Clostridium difficile was isolated from 15....... Resistance to =1 and = 3 antimicrobials was present in 31/232 (13.4%) and 6/232 (2.6%) respectively. Only two horses shed the same strain of toxigenic C. difficile for more than one month, indicating that shedding is transient. The high number of ribotype 078 is consistent with recent emergence of this...

  12. Effects of Breakpoint Changes on Carbapenem Susceptibility Rates ofEnterobacteriaceae: Results from the SENTRY Antimicrobial Surveillance Program, United States, 2008 to 2012

    Directory of Open Access Journals (Sweden)

    Robert P Rennie

    2014-01-01

    Full Text Available In the absence of clinical resistance, breakpoints for many antimicrobial agents are often set high. Clinical failures following use of the agents over time requires re-evaluation of breakpoints. This is based on patient response, pharmacokinetic/pharmacodynamic information and in vitro minimal inhibitory concentration data. Data from the SENTRY Antimicrobial Surveillance Program has shown that Clinical and Laboratory Standards Institute breakpoint changes for carbapenems that occurred between 2008 and 2012 in North America have resulted in decreased levels of susceptibility for some species. In particular, reduced susceptibility to imipenem was observed for Proteus mirabilis (35% and Morganella morganii (80%. Minor decreases in susceptibility were also noted for Enterobacter species with ertapenem (5% and imipenem (4.3%, and Serratia species with imipenem (6.4%. No significant decreases in susceptibility were observed for meropenem following the breakpoint changes. There were no earlier breakpoints established for doripenem. Very few of these Enterobacteriaceae produce carbapenamase enzymes; therefore, the clinical significance of these changes has not yet been clearly determined. In conclusion, ongoing surveillance studies with in vitro minimum inhibitory concentration data are essential in predicting the need for breakpoint changes and in identifying the impact of such changes on the percent susceptibility of different species.

  13. Characterization of Renibacterium salmoninarum with reduced susceptibility to macrolide antibiotics by a standardized antibiotic susceptibility test.

    Science.gov (United States)

    Rhodes, Linda D; Nguyen, Oanh T; Deinhard, Rebecca K; White, Teresa M; Harrell, Lee W; Roberts, Marilyn C

    2008-08-01

    Three cohorts of juvenile and subadult Chinook salmon Oncorhynchus tshawytscha received multiple treatments with macrolide antibiotics for bacterial kidney disease (BKD) during rearing in a captive broodstock program. A total of 77 mortalities among the cohorts were screened for Renibacterium salmoninarum, the etiologic agent of BKD, by agar culture from kidney, and isolates from 7 fish were suitable for growth testing in the presence of macrolide antibiotics. The minimum inhibitory concentration (MIC) of erythromycin and azithromycin was determined by a modification of the standardized broth assay using defined medium. The American Type Culture Collection (ATCC) type strain 33209 exhibited a MIC of 0.008 microg m(-1) to either erythromycin or azithromycin. Isolates from 3 fish displayed MICs identical to the MICs for the ATCC type strain 33209. In contrast, isolates from 4 fish exhibited higher MICs, ranging between 0.125 and 0.250 microg ml(-1) for erythromycin and between 0.016 and 0.031 microg ml(-1) for azithromycin. Sequence analysis of the mutational hotspots for macrolide resistance in the 23S rDNA gene and the open reading frames of ribosomal proteins L4 and L22 found identical sequences among all isolates, indicating that the phenotype was not due to mutations associated with the drug-binding site of 23S rRNA. These results are the first report of R. salmoninarum with reduced susceptibility to macrolide antibiotics isolated from fish receiving multiple antibiotic treatments. PMID:18814542

  14. Staphylococcus aureus antimicrobial susceptibility of abscess samples from adults and children from the Kaleida Health System in western New York State, 2003 to 2006.

    Science.gov (United States)

    Hsiao, Chiu-Bin; Dryja, Diane; Abbatessa, Laurie; Patel, Pravin H

    2010-05-01

    Staphylococcus aureus is the most common etiologic agent of skin abscesses. The regional rate of methicillin-resistant S. aureus (MRSA) abscesses may reflect the prevalence of local community-acquired MRSA (CAMRSA). A retrospective study was conducted to compare the antimicrobial susceptibility patterns of S. aureus isolates recovered from abscesses from 2003 to 2006 from patients at hospitals of the Kaleida Health System in western New York. S. aureus susceptibility information was obtained from a Vitek Legacy system, and the location and source of each isolate were identified. EpiInfo software was used to analyze the antimicrobial susceptibilities of all isolates and the trends in the rates of MRSA. A total of 2,848 S. aureus abscesses were identified by the Kaleida Health Clinical Microbiology Laboratory. Of those, 978 S. aureus abscess events occurred in four hospitals, including three adult facilities (547 episodes with 62 cases of bacteremia) and one children's facility (431 episodes with 2 cases of bacteremia). The MRSA rates in adults increased from 56% (2003) to 71% (2006), and that in children increased from 26% (2003) to 64% (2006). Of the MRSA isolates in the children's samples, more than 92% were susceptible to clindamycin. Of the MRSA isolates in the adult samples, 50% were susceptible to clindamycin in 2003 and 2004, whereas greater than 75% were susceptible in 2005 and 2006. The increased rates of MRSA abscesses with susceptibility to clindamycin may reflect the high prevalence level of CAMRSA in the western New York community. The variations in S. aureus susceptibilities could serve as an indicator of the changing resistance patterns within a broad urban community. PMID:20181909

  15. Prevalence of Urinary Tract Infection and Antimicrobial Susceptibility among Diabetic Patients with Controlled and Uncontrolled Glycemia in Kuwait

    Science.gov (United States)

    Sewify, May; Nair, Shinu; Warsame, Samia; Murad, Mohamed; Alhubail, Asma; Behbehani, Kazem; Al-Refaei, Faisal; Tiss, Ali

    2016-01-01

    Diabetic patients have higher risk of urinary tract infection (UTI). In the present study, we investigated the impact of glycemic control in diabetic patients on UTI prevalence, type of strains, and their antimicrobial drugs susceptibility. This study was conducted on urine samples from 722 adult diabetic patients from which 252 (35%) samples were positive for uropathogens. Most UTI cases occurred in the uncontrolled glycemic group (197 patients) versus 55 patients with controlled glycemia. Higher glycemic levels were measured in uncontrolled glycemia group (HbA1c = 8.3 ± 1.5 and 5.4 ± 0.4, resp., P < 0.0001). Females showed much higher prevalence of UTI than males in both glycemic groups (88.5% and 11.5%, resp., P < 0.0001). In the uncontrolled glycemia group 90.9% of the UTI cases happened at ages above 40 years and a clear correlation was obtained between patient age ranges and number of UTI cases (r = 0.94; P = 0.017), whereas in the group with controlled glycemia no trend was observed. Escherichia coli was the predominant uropathogen followed by Klebsiella pneumoniae and they were together involved in 76.2% of UTI cases. Those species were similarly present in both diabetic groups and displayed comparable antibiotic resistance pattern. These results highlight the importance of controlling glycemia in diabetic patients to reduce the UTI regardless of age and gender. PMID:26844231

  16. Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

    Directory of Open Access Journals (Sweden)

    I. Fernández-Natal

    2016-03-01

    Full Text Available During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β-lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species.

  17. Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples.

    Science.gov (United States)

    Fernández-Natal, I; Sáez-Nieto, J A; Rodríguez-Lázaro, D; Valdezate-Ramos, S; Parras-Padilla, T; Medina, M J; Rodríguez-Pollán, R H; Blom, J; Tauch, A; Soriano, F

    2016-03-01

    During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β-lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X) resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species. PMID:26933505

  18. Species distribution and antimicrobial susceptibility of enterococci isolated from broilers infected experimentally with Eimeria spp and fed with diets containing different supplements

    OpenAIRE

    Cassenego, A.P.V.; d’Azevedo, P.A.; A.M.L. Ribeiro; Frazzon, J.; Van Der Sand, S.T.; Frazzon, A. P. G.

    2011-01-01

    Resistant bacteria in animal can be spread to environment and to humans. Poultry feed and infections caused by Eimeria spp. are important factors in determining the intestinal microbial communities. The aim of this study was to verify the prevalence of species and antimicrobial susceptibility of Enterococcus isolated from broilers fed with different supplements and infected experimentally with Eimeria spp. Broilers were divided in eight groups, fed with diets supplemented with a combination o...

  19. In vitro antimicrobial susceptibility of Mycoplasma mycoides mycoides large colony and Arcanobacterium pyogenes isolated from clinical cases of ulcerative balanitis and vulvitis in Dorper sheep in South Africa

    OpenAIRE

    A. Kidanemariam; J. Gouws; M. Van Vuuren; Gummow, B.

    2005-01-01

    The in vitro activities of enrofloxacin, florfenicol, oxytetracycline and spiramycin were determined against field isolates of Mycoplasma mycoides mycoides large colony (MmmLC) by means of the broth microdilution technique. The minimum inhibitory concentrations (MICs) of these antimicrobial drugs were determined for a representative number of 10 isolates and 1 type strain. The susceptibility of Arcanobacterium pyogenes to enrofloxacin, oxytetracycline and tilmicosin was determined by means of...

  20. Isolation, identification and antimicrobial susceptibility of Pantoea (Enterobacter) agglomerans isolated from consumed powdered infant formula milk (PIF) in NICU ward: First report from Iran

    OpenAIRE

    Jalal Mardaneh; Mohammad Mehdi Soltan Dallal

    2013-01-01

    Background and Objectives Pantoea agglomerans is a Gram-negative rod in the Enterobacteriaceae family. It is reported as both commensal and opportunistic pathogen of animals and humans. This organism is potential candidates as powdered infant milk formula-borne opportunistic pathogen. The aim of our study was to perform isolation, identification and antimicrobial susceptibility pattern of Pantoea (Enterobacter) agglomerans strains isolated from consumed powdered infant formula milk (PIF) in N...

  1. Escherichia coli Strains Isolated from the Uteri Horn, Mouth, and Rectum of Bitches Suffering from Pyometra: Virulence Factors, Antimicrobial Susceptibilities, and Clonal Relationships among Strains

    OpenAIRE

    Agostinho, Juliana M. A.; Andressa de Souza; Schocken-Iturrino, Ruben P.; Beraldo, Lívia G.; Borges, Clarissa A.; Fernando A. Ávila; José M. Marin

    2014-01-01

    Pyometra is recognized as one of the main causes of disease and death in the bitch, and Escherichia coli is the major pathogen associated with this disease. In this study, 70 E. coli isolates from the uteri horn, mouth, and rectum of bitches suffering from the disease and 43 E. coli isolates from the rectum of clinically healthy bitches were examined for the presence of uropathogenic virulence genes and susceptibility to antimicrobial drugs. DNA profiles of isolates from uteri horn and mouth ...

  2. Antimicrobial Susceptibility of Bloodstream Isolates of Staphylococcus aureus: Global Results from the Tigecycline Evaluation and Surveillance Trial, 2004-2008

    Directory of Open Access Journals (Sweden)

    Daniel Amsterdam

    2010-01-01

    Full Text Available Problem statement: The Tigecycline Evaluation and Surveillance Trial (TEST commenced in 2004 to monitor the activity of tigecycline, a new glycylcycline and numerous comparators against major hospital-and community-associated pathogens. In this report we examine the efficacy of tigecycline and comparators against isolates of Staphylococcus aureus collected from blood. Approach: Almost 4000 blood-derived isolates of Staphylococcus aureus were collected from participating centers globally between 2004-2008. Results: All isolates were susceptible to tigecycline (MIC90 0.25 mg L-1 and linezolid (MIC90 4 mg L-1; 99.9% of isolates were susceptible to vancomycin (MIC90 1 mg L-1. Tigecycline and linezolid activity were unaffected by resistance to methicillin, ICU vs non-ICU isolate collection or the age of patients from which the isolates were collected. Although 95.3% of MSSA were levofloxacin susceptible, only 14.4% of MRSA isolates were susceptible to levofloxacin in this study. Conclusion: Tigecycline is shown here to be active against S. aureus isolates collected from blood and is unaffected by methicillin resistance. However, tigecycline is not as yet approved for the treatment of bacteremic infections.

  3. Rifaximin disc diffusion test for in vitro susceptibility testing of Clostridium difficile

    OpenAIRE

    Huhulescu, Steliana; Sagel, Ulrich; Fiedler, Anita; Pecavar, Verena; Blaschitz, Marion; Wewalka, Guenther; Allerberger, Franz; Indra, Alexander

    2011-01-01

    Rifaximin is a rifampicin derivative, poorly absorbed by the gastro-intestinal tract. We studied the in vitro susceptibility to rifamixin of 1082 Clostridium difficile isolates; among these,184 isolates from a strain collection were tested by an in-house rifaximin disc (40 µg) diffusion test, by an in-house rifaximin broth microdilution test, by rifampicin Etest and by rpoB gene sequencing. In the absence of respective CLSI or EUCAST MIC breakpoints for rifaximin and rifampicin against C. dif...

  4. Using Soxhlet Ethanol Extraction to Produce and Test Plant Material (Essential Oils) for Their Antimicrobial Properties †

    OpenAIRE

    James Redfern; Malcolm Kinninmonth; Dariel Burdass; Joanna Verran

    2014-01-01

    As the issue of antimicrobial resistance continues to grow, there is a renewed interest in deriving antimicrobial products from natural compounds, particularly extracts from plant materials. This paper describes how essential oil can be extracted from the common herb, thyme (Thymus vulgaris) in the classroom. Subsequently, the extract can be tested for its antimicrobial activity. A number of variables are suggested.

  5. Antimicrobial susceptibility and genetic characteristics of Haemophilus influenzae isolated from community-acquired respiratory tract infection patients in Shanghai City, China.

    Science.gov (United States)

    Qin, Liang; Zhou, Zhaoyan; Hu, Bijie; Yamamoto, Taro; Watanabe, Hiroshi

    2012-08-01

    Haemophilus influenzae is an important causative pathogen of community-acquired respiratory infection in China. In this study we investigated 37 H. influenzae strains isolated from patients with community-acquired respiratory tract infections (CARTI) in Shanghai city between Dec 2008 and Apr 2009. H. influenzae clinical isolates were identified, and b-lactamase production tests were conducted and minimal inhibitory concentrations(MIC) were measured. Pulsed-field gel electrophoresis(PFGE) was introduced as an effective finger printing method. Two isolates (5.4%) were verified as serotype b strains, and 30 strains (81.1%) were nontypeable H. influenzae. Furthermore, 10 (27.0%) were b-lactamase-producing ampicillin-resistance (BLPAR) (TEM-1 type)strains, 11 (29.8%) were low-b-lactamase-nonproducing ampicillin-resistant H. influenzae (Low-BLNAR) strains,and the rest were b-lactamase-negative ampicillin-susceptible(BLNAS) strains. Minimum inhibitory concentrations(MIC90; lg/ml) were 2 for ampicillin/sulbactam, 0.05 force fotaxime, 16 for cefaclor, 2 for azithromycin, 0.12 for levofloxacin, and 4 for imipenem. Fingerprint typing by PFGE revealed 23 independent patterns for the isolates. Pattern A (defined in this study) was predominant in BLPAR strains, and a variety of other patterns were detected in Low-BLNAR and BLNAS strains. Although the incidence of ampicillin resistant H. influenzae is increasing in CARTI patients in China, current antimicrobial chemotherapy seems to be effective. PMID:22302696

  6. [Antimicrobial susceptibility of clinical isolates of aerobic Gram-positive cocci and anaerobic bacteria in 2006].

    Science.gov (United States)

    Yamaguchi, Takahiro; Yoshida, Isamu; Itoh, Yoshihisa; Tachibana, Mineji; Takahashi, Choichiro; Kaku, Mitsuo; Kanemitsu, Keiji; Okada, Masahiko; Horikawa, Yoshinori; Shiotani, Joji; Kino, Hiroyoshi; Ono, Yuka; Baba, Hisashi; Matsuo, Shuji; Asari, Seishi; Toyokawa, Masahiro; Matsuoka, Kimiko; Kusano, Nobuchika; Nose, Motoko; Murase, Mitsuharu; Miyamoto, Hitoshi; Saikawa, Tetsunori; Hiramatsu, Kazufumi; Kohno, Shigeru; Yanagihara, Katsunori; Yamane, Nobuhisa; Nakasone, Isamu; Maki, Hideki; Yamano, Yoshinori

    2010-12-01

    The activity of antibacterial agents against aerobic Gram-positive cocci (26 species, 1022 strains) and anaerobic bacteria (23 species, 184 strains) isolated from clinical specimens in 2006 at 16 clinical facilities in Japan were studied using either broth microdilution or agar dilution method. The ratio of methicillin-resistant strains among Staphylococcus aureus and Staphylococcus epidermidis was 53.0% and 65.8%, suggesting that resistant strains were isolated at high frequency. Vancomycin (VCM) and quinupristin/dalfopristin (QPR/DPR) had good antibacterial activity against methicillin-resistant S. aureus and methicillin-resistant S. epidermidis, with MIC90s of < or = 2 micrcog/mL. The ratio of penicillin (PC) intermediate and resistant strains classified by mutations of PC-binding proteins among Streptococcus pneumoniae was 87.6%. Ceftriaxone, cefpirome, cefepime, carbapenem antibiotics, VCM, teicoplanin, linezolid(LZD) and QPR/DPR had MIC90s of < or = 1 microg/mL against PC-intermediate and resistant S. pneumoniae strains. Against all strains of Enterococcus faecalis and Enterococcus faecium, the MICs of VCM and TEIC were under 2 microg/mL, and no resistant strain was detected, suggesting that these agents had excellent activities against these species. 10.9% of E. faecalis strains or 3.5% of E. faecium strains showed intermediate or resistant to LZD. 24.4% of E. faecium strains showed intermediate or resistant to QPR/DPR. Against all strains of Clostridium difficile, the MIC of VCM were under 1 microg/mL, suggesting that VCM had excellent activity against C. difficile. Carbapenems showed good activity against Peptococcaceae, Bacteroides spp., and Prevotella spp. However since several strains of Bacteroides fragilis showed resistant to carbapenems and the susceptibility of this species should be well-focused in the future. PMID:21425596

  7. Molecular characterization and antimicrobial susceptibility of nasal Staphylococcus aureus isolates from a Chinese medical college campus.

    Science.gov (United States)

    Du, Jimei; Chen, Chun; Ding, Baixing; Tu, Jinjing; Qin, Zhiqiang; Parsons, Chris; Salgado, Cassandra; Cai, Qiangjun; Song, Yulong; Bao, Qiyu; Zhang, Liming; Pan, Jingye; Wang, Liangxing; Yu, Fangyou

    2011-01-01

    Staphylococcus aureus colonization and infection occur more commonly among persons living or working in crowded conditions, but characterization of S. aureus colonization within medical communities in China is lacking. A total of 144 (15.4%, 144/935) S. aureus isolates, including 28 (3.0%, 28/935) MRSA isolates, were recovered from the nares of 935 healthy human volunteers residing on a Chinese medical college campus. All S. aureus isolates were susceptible to vancomycin, quinupristin/dalfopristin and linezolid but the majority were resistant to penicillin (96.5%), ampicillin/sulbactam (83.3%) and trimethoprim/sulfamethoxazole (93.1%). 82%, (23/28) of the MRSA isolates and 66% (77/116) of the MSSA isolates were resistant to multiple antibiotics, and 3 MRSA isolates were resistant to mupirocin--an agent commonly used for nasal decolonization. 16 different sequence types (STs), as well as SCCmec genes II, III, IVd, and V, were represented among MRSA isolates. We also identified, for the first time, two novel STs (ST1778 and ST1779) and 5 novel spa types for MRSA. MRSA isolates were distributed in different sporadic clones, and ST59-MRSA-VId- t437 was found within 3 MRSA isolates. Moreover, one isolate with multidrug resistance belonging to ST398-MRSA-V- t571 associated with animal infections was identified, and 3 isolates distributed in three different clones harbored PVL genes. Collectively, these data indicate a high prevalence of nasal MRSA carriage and molecular heterogeneity of S. aureus isolates among persons residing on a Chinese medical college campus. Identification of epidemic MRSA clones associated with community infection supports the need for more effective infection control measures to reduce nasal carriage and prevent dissemination of MRSA to hospitalized patients and health care workers in this community. PMID:22114670

  8. [Antimicrobial susceptibility of clinical isolates of aerobic gram-positive cocci and anaerobic bacteria in 2008].

    Science.gov (United States)

    Yoshida, Isamu; Yamaguchi, Takahiro; Kudo, Reiko; Fuji, Rieko; Takahashi, Choichiro; Oota, Reiko; Kaku, Mitsuo; Kunishima, Hiroyuki; Okada, Masahiko; Horikawa, Yoshinori; Shiotani, Joji; Kino, Hiroyoshi; Ono, Yuka; Fujita, Shinichi; Matsuo, Shuji; Kono, Hisashi; Asari, Seishi; Toyokawa, Masahiro; Kusano, Nobuchika; Nose, Motoko; Horii, Toshinobu; Tanimoto, Ayako; Miyamoto, Hitoshi; Saikawa, Tetsunori; Hiramatsu, Kazufumi; Kohno, Shigeru; Yanagihara, Katsunori; Yamane, Nobuhisa; Nakasone, Isamu; Maki, Hideki; Yamano, Yoshinori

    2012-02-01

    The activity of antibacterial agents against aerobic Gram-positive cocci (25 genus or species, 1029 strains) and anaerobic bacteria (21 genus or species, 187 strains) isolated from clinical specimens in 2008 at 16 clinical facilities in Japan were studied using either broth microdilution or agar dilution method. The ratio of methicillin-resistant strains among Staphylococcus aureus and Staphylococcus epidermidis was 59.6% and 81.2%, suggesting that resistant strains were isolated at high frequency. Vancomycin (VCM), linezolid (LZD) and quinupristin/dalfopristin (QPR/DPR) had good antibacterial activity against methicillin-resistant S. aureus and methicillin-resistant S. epidermidis, with MIC90s of < or = 2 microg/mL. The ratio of penicillin (PC) intermediate and resistant strains classified by mutations of PC-binding proteins among Streptococcus pneumoniae was 92.0% that was highest among our previous reports. Cefpirome, carbapenems, VCM, teicoplanin (TEIC), LZD and QPR/DPR had MIC90s of < or = 1 microg/mL against PC-intermediate and resistant S. pneumoniae strains. Against all strains of Enterococcus faecalis and Enterococcus faecium, the MICs of VCM and TEIC were under 2 microg/mL, and no resistant strain was detected, suggesting that these agents had excellent activities against these species. 15.9% of E. faecalis strains and 1.2% of E. faecium strains showed intermediate to LZD. 17.1% of E. faecium strains showed intermediate or resistant to QPR/DPR. Against all strains of Clostridium difficile, the MIC of VCM was under 1 microg/mL, suggesting that VCM had excellent activity. Carbapenems showed good activity against Clostridiales, Bacteroides spp., and Prevotella spp., but one strain of Bacteroides fragilis showed resistant to carbapenems. And so, the susceptibility of this species should be well-focused in the future at detecting continuously. PMID:22808693

  9. Molecular characterization and antimicrobial susceptibility of nasal Staphylococcus aureus isolates from a Chinese medical college campus.

    Directory of Open Access Journals (Sweden)

    Jimei Du

    Full Text Available Staphylococcus aureus colonization and infection occur more commonly among persons living or working in crowded conditions, but characterization of S. aureus colonization within medical communities in China is lacking. A total of 144 (15.4%, 144/935 S. aureus isolates, including 28 (3.0%, 28/935 MRSA isolates, were recovered from the nares of 935 healthy human volunteers residing on a Chinese medical college campus. All S. aureus isolates were susceptible to vancomycin, quinupristin/dalfopristin and linezolid but the majority were resistant to penicillin (96.5%, ampicillin/sulbactam (83.3% and trimethoprim/sulfamethoxazole (93.1%. 82%, (23/28 of the MRSA isolates and 66% (77/116 of the MSSA isolates were resistant to multiple antibiotics, and 3 MRSA isolates were resistant to mupirocin--an agent commonly used for nasal decolonization. 16 different sequence types (STs, as well as SCCmec genes II, III, IVd, and V, were represented among MRSA isolates. We also identified, for the first time, two novel STs (ST1778 and ST1779 and 5 novel spa types for MRSA. MRSA isolates were distributed in different sporadic clones, and ST59-MRSA-VId- t437 was found within 3 MRSA isolates. Moreover, one isolate with multidrug resistance belonging to ST398-MRSA-V- t571 associated with animal infections was identified, and 3 isolates distributed in three different clones harbored PVL genes. Collectively, these data indicate a high prevalence of nasal MRSA carriage and molecular heterogeneity of S. aureus isolates among persons residing on a Chinese medical college campus. Identification of epidemic MRSA clones associated with community infection supports the need for more effective infection control measures to reduce nasal carriage and prevent dissemination of MRSA to hospitalized patients and health care workers in this community.

  10. Antimicrobial Susceptibilities of Aerobic and Facultative Gram-Negative Bacilli from Intra-abdominal Infections in Patients from Seven Regions in China in 2012 and 2013.

    Science.gov (United States)

    Zhang, Hui; Yang, Qiwen; Liao, Kang; Ni, Yuxing; Yu, Yunsong; Hu, Bijie; Sun, Ziyong; Huang, Wenxiang; Wang, Yong; Wu, Anhua; Feng, Xianju; Luo, Yanping; Hu, Zhidong; Chu, Yunzhuo; Chen, Shulan; Cao, Bin; Su, Jianrong; Gui, Bingdong; Duan, Qiong; Zhang, Shufang; Shao, Haifeng; Kong, Haishen; Badal, Robert E; Xu, Yingchun

    2016-01-01

    To evaluate the antimicrobial susceptibility of Gram-negative bacilli that caused hospital-acquired and community-acquired intra-abdominal infections (IAIs) in China between 2012 and 2013, we determined the susceptibilities to 12 antimicrobials and the extended-spectrum β-lactamase (ESBL) statuses of 3,540 IAI isolates from seven geographic areas in China in a central laboratory using CLSI broth microdilution and interpretive standards. Most infections were caused by Escherichia coli (46.3%) and Klebsiella pneumoniae (19.7%). Rates of ESBL-producing E. coli (P = 0.031), K. pneumoniae (P = 0.017), and Proteus mirabilis (P = 0.004) were higher in hospital-acquired IAIs than in community-acquired IAIs. Susceptibilities of enterobacteriaceae to ertapenem, amikacin, piperacillin-tazobactam, and imipenem were 71.3% to 100%, 81.3% to 100%, 64.7% to 100%, and 83.1% to 100%, respectively, but imipenem was ineffective against P. mirabilis (<20%). Although most ESBL-positive hospital-acquired isolates were resistant to third- and fourth-generation cephalosporins, the majority were susceptible to cefoxitin (47.9% to 83.9%). Susceptibilities of ESBL-positive isolates to ampicillin-sulbactam (<10%) were low, whereas susceptibilities to ciprofloxacin (0% to 54.6%) and levofloxacin (0% to 63.6%) varied substantially. The prevalences of cephalosporin-susceptible E. coli and K. pneumoniae were higher in the northeastern and southern regions than in the central and eastern regions, reflecting the ESBL-positive rates in these areas, and were lowest in the Jiangsu-Zhejiang (Jiang-Zhe) area where the rates of carbapenem resistance were also highest. Ertapenem, amikacin, piperacillin-tazobactam, and imipenem are the most efficacious antibiotics for treating IAIs in China, especially those caused by E. coli or K. pneumoniae. Resistance to cephalosporins and carbapenems is more common in the Jiang-Zhe area than in other regions in China. PMID:26482308

  11. Activity of telavancin and comparator antimicrobial agents tested against Staphylococcus spp. isolated from hospitalised patients in Europe (2007-2008).

    Science.gov (United States)

    Mendes, Rodrigo E; Sader, Helio S; Jones, Ronald N

    2010-10-01

    The activity of telavancin was evaluated against Staphylococcus spp. collected from European hospitals as part of an international surveillance study (2007-2008). A total of 7534 staphylococcal clinical isolates [5726 Staphylococcus aureus and 1808 coagulase-negative staphylococci (CoNS)] were included. Isolates were tested for susceptibility according to reference methods and minimum inhibitory concentration (MIC) values were interpreted based on Clinical and Laboratory Standards Institute (CLSI) 2010 and European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2009 criteria. Telavancin breakpoints approved by the US Food and Drug Administration (FDA) were applied. Telavancin activity was evaluated against meticillin-resistant S. aureus (MRSA) displaying several antibiogram resistance patterns, including multidrug-resistant isolates. Telavancin was active against S. aureus [MIC(50/90) values (MICs for 50% and 90% of the isolates, respectively)=0.12/0.25mg/L; 100.0% susceptible] and CoNS (MIC(50/90)=0.12/0.25mg/L), inhibiting all isolates at quinupristin/dalfopristin, vancomycin and linezolid). Based upon MIC(90) values, telavancin demonstrated potent in vitro activity against a contemporary (2007-2008) collection of Staphylococcus spp. recovered from nearly 30 European medical centres. PMID:20598860

  12. Antimicrobial Susceptibility of Bacteria Causing Neonatal Infections%新生儿临床标本抗生素敏感性分析

    Institute of Scientific and Technical Information of China (English)

    余加林; 吴仕孝

    2001-01-01

    目的:探索新生儿感染病原菌分布及常见抗菌药物敏感性,为经验性治疗提供依据。方法:按《全国临床检验操作规程》鉴定细菌,纸片扩散法做药敏试验。结果:1987~1998年内分离出病原菌2 244株。院外感染前三位是表皮葡萄球菌、腐生葡萄球菌及大肠埃希菌,院内感染前三位是大肠埃希菌、克雷白菌及绿脓杆菌。院内外感染菌株对青霉素、氨苄西林等15种抗生素的耐药率差异显著。阿米卡星的总敏感率86.2%,与青霉素联用敏感率增至89.0%。结论:院外感染致病菌以革兰阳性菌为主,而院内感染致病菌以革兰阴性菌为主,后者对许多抗菌药物更易产生耐药性,阿米卡星联合青霉素作为第一线抗菌药物值得推广。%Objective:To investigate the epidemiological characteristics of bacteria and their susceptibility to antimicrobials and to establish a basis for empirical treatment of the neonatal infections.  Methods:Identification of bacteria were performed according to the National Standard of Clinical Microbiological Test. Disk diffusion were used for antimicrobial susceptibility test. Results: A total of 2,244 strains were isolated from the samples collected in our neonatal ward from Jan. 1987 to Dec. 1998. The predominant species ranked the first three were Staphylococcus epidermidis, Staphylococcus saprophyticus and Escherichia coli in the group I (infections acquired outside of hospital). Escherichia coli, Klebsiella and pseudomonas aeruginosa ranked the first three in the group Ⅱ(nosocomial infections). The resistance rates of bacterial isolates from group Ⅱ to antimicrobial agents including penicillin and ampicillin were significantly higher than that from group I (P<0.05). The sensitivity rate was 82.2% by using amikacin only, but raised to 89% when combined with penicillin.  Conclusion: Gram-negative bacteria were the main pathogens of nosocomial infections

  13. Bile Culture and Susceptibility Testing of Malignant Biliary Obstruction via PTBD

    International Nuclear Information System (INIS)

    Purpose: To assess the information obtained by bile culture and susceptibility testing for malignant biliary obstruction by a retrospective one-center study. Methods: A total of 694 patients with malignant biliary obstruction received percutaneous transhepatic biliary drainage during the period July 2003 to September 2010, and subsequently, bile specimens were collected during the procedure. Among the 694 patients, 485 were men and 209 were women, ranging in age from 38 to 78 years (mean age 62 years). Results: A total of 42.9% patients had a positive bile culture (298 of 694). Further, 57 species of microorganisms and 342 strains were identified; gram-positive bacteria accounted for 50.9% (174 of 342) and gram-negative bacteria accounted for 41.5% (142 of 342) of these strains. No anaerobes were obtained by culture during this study. The most common microorganisms were Enterococcus faecalis (41 of 342, 11.9%), Escherichia coli (34 of 342, 9.9%), Klebsiella pneumoniae (28 of 342, 8.2%), Staphylococcus epidermidis (19 of 342, 5.5%), Enterococcus (18 of 342, 5.3%), and Enterobacter cloacae (16 of 342, 4.7%). The percentage of β-lactamase-producing gram-positive bacteria was 27.6% (48 of 174), and the percentage of gram-negative bacteria was 19.7% (28 of 142). The percentage of enzyme-producing Escherichia coli was 61.7% (21 of 34). Conclusion: The bile cultures in malignant biliary obstruction are different from those in the Tokyo Guidelines and other benign biliary obstruction researches, which indicates that a different antibacterial therapy should be applied. Thus, knowledge of the antimicrobial susceptibility data could aid in the better use of antibiotics for the empirical therapy of biliary infection combined with malignant biliary obstruction.

  14. Bile Culture and Susceptibility Testing of Malignant Biliary Obstruction via PTBD

    Energy Technology Data Exchange (ETDEWEB)

    Yu Haipeng; Guo Zhi, E-mail: jieruke@yahoo.com.cn; Xing Wenge; Guo Xiuying; Liu Fang; Li Baoguo [Tinajin Medical University Cancer Institute and Hospital, Department of Interventional Therapy, Tianjin Key Cancer Prevention and Treatment Laboratory (China)

    2012-10-15

    Purpose: To assess the information obtained by bile culture and susceptibility testing for malignant biliary obstruction by a retrospective one-center study. Methods: A total of 694 patients with malignant biliary obstruction received percutaneous transhepatic biliary drainage during the period July 2003 to September 2010, and subsequently, bile specimens were collected during the procedure. Among the 694 patients, 485 were men and 209 were women, ranging in age from 38 to 78 years (mean age 62 years). Results: A total of 42.9% patients had a positive bile culture (298 of 694). Further, 57 species of microorganisms and 342 strains were identified; gram-positive bacteria accounted for 50.9% (174 of 342) and gram-negative bacteria accounted for 41.5% (142 of 342) of these strains. No anaerobes were obtained by culture during this study. The most common microorganisms were Enterococcus faecalis (41 of 342, 11.9%), Escherichia coli (34 of 342, 9.9%), Klebsiella pneumoniae (28 of 342, 8.2%), Staphylococcus epidermidis (19 of 342, 5.5%), Enterococcus (18 of 342, 5.3%), and Enterobacter cloacae (16 of 342, 4.7%). The percentage of {beta}-lactamase-producing gram-positive bacteria was 27.6% (48 of 174), and the percentage of gram-negative bacteria was 19.7% (28 of 142). The percentage of enzyme-producing Escherichia coli was 61.7% (21 of 34). Conclusion: The bile cultures in malignant biliary obstruction are different from those in the Tokyo Guidelines and other benign biliary obstruction researches, which indicates that a different antibacterial therapy should be applied. Thus, knowledge of the antimicrobial susceptibility data could aid in the better use of antibiotics for the empirical therapy of biliary infection combined with malignant biliary obstruction.

  15. Typhoid outbreak in Songkhla, Thailand 2009-2011: clinical outcomes, susceptibility patterns, and reliability of serology tests.

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    Wannee Limpitikul

    Full Text Available OBJECTIVE: To determine the clinical manifestations and outcomes, the reliability of Salmonella enterica serotype Typhi (S ser. Typhi IgM and IgG rapid tests, and the susceptibility patterns and the response to treatment during the 2009-2011 typhoid outbreak in Songkhla province in Thailand. METHOD: The medical records of children aged <15 years with S ser. Typhi bacteremia were analysed. The efficacy of the typhoid IgM and IgG rapid tests and susceptibility of the S ser. Typhi to the current main antibiotics used for typhoid (amoxicillin, ampicillin, cefotaxime, ceftriaxone, co-trimoxazole, and ciprofloxacin, were evaluated. RESULTS: S ser. Typhi bacteremia was found in 368 patients, and all isolated strains were susceptible to all 6 antimicrobials tested. Most of the patients were treated with ciprofloxacin for 7-14 days. The median time (IQR of fever before treatment and duration of fever after treatment were 5 (4, 7 days and 4 (3, 5 days, respectively. Complications of ascites, lower respiratory symptoms, anemia (Hct <30%, and ileal perforation were found in 7, 7, 22, and 1 patients, respectively. None of the patients had recurrent infection or died. The sensitivities of the typhoid IgM and IgG tests were 58.3% and 25.6% respectively, and specificities were 74.1% and 50.5%, respectively. CONCLUSION: Most of the patients were diagnosed at an early stage and treated with a good outcome. All S ser. Typhi strains were susceptible to standard first line antibiotic typhoid treatment. The typhoid IgM and IgG rapid tests had low sensitivity and moderate specificity.

  16. Antimicrobial susceptibility of Staphylococcus hyicus Isolated from exudative epidermitis in pigs

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Watts, J.L.; Salmon, S.A.; Yancey, R.J.

    1994-01-01

    compounds, with MIC(90)s of 0.25, 0.5, and 1.0 mu g/ml, respectively. However, 41.4% of the 99 strains tested were positive for beta-lactamase production. The MIC(90)s of erythromycin, tetracycline, and streptomycin were >32.0 mu g/ml. Initial testing with sulfadiazine-trimethoprim yielded an MIC(90) of >64...... the two compounds at ratios of 1:2 (lincomycin to spectinomycin) and 1:8 were more active, with MIC(90)s of 16.0 and 4.0 mu g/ml, respectively. These results indicate that novobiocin and sulfadiazine-trimethoprim were the most active compounds tested against the S. hyicus strains isolated from pigs...

  17. Flow cytometry susceptibility testing for conventional antifungal drugs and Comparison with the NCCLS Broth Macrodilution Test

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    M.J. Najafzadeh

    2009-08-01

    Full Text Available Introduction: During the last decade, the incidence of fungal infection has been increased in many countries. Because of the advent of resistant to antifungal agents, determination of an efficient strategic plan for treatment of fungal disease is an important issue in clinical mycology. Many methods have been introduced and developed for determination of invitro susceptibility tests. During the recent years, flow cytometry has developed to solving the problem and many papers have documented the usefulness of this technique. Materials and methods: As the first step, the invitro susceptibility of standard PTCC (Persian Type of Culture Collection strain and some clinical isolates of Candida consisting of Candida albicans, C. dubliniensis, C. glabrata, C. kefyer and C. parapsilosis were evaluated by macrodilution broth method according to NCCLS (National Committee for Clinical Laboratory Standards guidelines and flow cytometry susceptibility test. Results:  The data indicated that macro dilution broth methods and flow cytometry have the same results in determination of MIC (Minimum Inhibitory Concentration for amphotericin B, clotrimazole, fluconazole, ketoconazole and miconazole in C. albicans PTCC 5027 as well as clinical Candida isolates, such as C.albicans, C.dubliniensis, C.glabrata C.kefyr, and C.parapsilosis. Discussion: Comparing the results obtained by macrodilution broth and flow cytometry methods revealed that flow cytometry was faster. It is suggested that flow cytometry susceptibility test can be used as a powerful tool for determination of MIC and administration of the best antifungal drug in treatment of patients with Candida infections.

  18. Finding of coagulase negative staphylococci in the herd with an increased number of somatic cells in milk and their antimicrobial susceptibility

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    Katić Vera

    2013-01-01

    Full Text Available Coagulase-negative staphylococci (CNS are generally considered to be opportunistic pathogens. Controlling CNS mastitis is difficult because the epidemiology is not clear, and the CNS group consists of about 40 different Staphylococcus species. Therefore, the aim of this study was to determine the prevalence of coagulasenegative staphylococci in milk of the cows with subclinical mastitis, as well as to determine different CNS species isolated from quarter milk samples for their susceptibility to antimicrobials used commonly for mastitis therapy. On the farm where there was found an increase of somatic cells in bulk milk, 112 dairy cows were examined by mastitis test. From 52 udder quarters where mastitis test showed an increase of somatic cells, milk samples were taken for bacteriological examination. For isolating the causes of mastitis there was used blood agar. Identification of the causative agents of mastitis was carried out on the basis of colony appearance on blood agar and their physiological characteristics. Coagulasepositive staphylococci sensitivity which cause mastitis was tested by Kirby Bauer method. For susceptibility testing there were used commercially produced discs containing: 10 IU penicillin, amoxicillin/clavulanic acid (20 +10 μg, cloxacillin 25 μg, 30 μg amoxicillin, cephalexin 30 μg, ceftiofur 30 μg, 15 μg lincomycin, gentamicin and tetracycline 30 μg. The sensitivity of microorganisms was evaluated on the basis of inhibition zone diameter recommended by the manufacturer and was labeled as sensitive (S moderately sensitive (I or resistant (R. Coagulase-negative staphylococci were isolated from 61.53% of samples from cows with subclinical mastitis, making them the most common cause of subclinical mastitis. The highest resistance of coagulase-negative staphylococci was found to penicillin G (58.33% of isolates. Full sensitivity of coagulase-negative staphylococci was found to amoxicillin / clavulanic acid (100% of

  19. Use of Aeromonas spp. as general indicators of antimicrobial susceptibility among bacteria in aquatic environments in Thailand

    OpenAIRE

    Masaru eUsui; Chie eTagaki; Akira eFukuda; Torahiko eOkubo; Chanchai eBoonla; Satoru eSuzuki; Kanako eSeki; Hideshige eTakada; Yutaka eTamura

    2016-01-01

    Antimicrobials are widely used, not only for treating human infections, but also for treatment of livestock and in fish farms. Human habitats in Southeastern Asian countries are located in close proximity to aquatic environments. As such, the human populations within these regions are at risk of exposure to antimicrobial resistant bacteria (ARB), and thereby disseminating antimicrobial resistance genes (ARGs). In this study, we collected water samples from 15 sites (5 sites in Chao Phraya Riv...

  20. THE EFFECTIVENESS OF ANTIMICROBIAL PRESERVATIVES TESTING OF THE MEDICINE "EFIAL"

    OpenAIRE

    Borshchevskiy GI; Railko ZО; Reida VP

    2015-01-01

    Dosage form - spray is one of the most advanced and modern methods of medicines administration in the human body. The advantage of airborne mode of medicines delivery (inhalation) than injection and enterable methods is the ability to direct and rapid impact on the area of inflammation of the mucous membranes or when fine evaporation - on the bronchi and lungs. When finished medicinal product itself has not a sufficient antimicrobial activity, in its composition can be...

  1. BSAC standardized disc susceptibility testing method (version 8).

    Science.gov (United States)

    Andrews, J M

    2009-09-01

    azithromycin, clarithromycin, erythromycin and telithromycin (Table 15); clarithromycin and erythromycin MIC and zone diameter BPs for Moraxella catarrhalis (Table 16); azithromycin MIC BPs for Neisseria gonorrhoeae (Table 17); chloramphenicol and rifampicin MIC BPs for Neisseria meningitidis (Table 18); azithromycin MIC BPs for Haemophilus influenzae (Table 19); MIC BPs for metronidazole for Bacteroides fragilis, Bacteroides thetaiotaomicron and Clostridium perfringens (Tables 23-25, respectively); susceptibility testing of Listeria spp. (Appendix 3); the acceptable range for ATCC 25923 to a 10 microg tobramycin disc (Table 26). PMID:19587067

  2. [Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1995). III. Differences in susceptibilities from previous years].

    Science.gov (United States)

    Kumamoto, Y; Tsukamoto, T; Hirose, T; Yokoo, A; Hikichi, Y; Shigeta, S; Takahashi, T; Shiraiwa, Y; Ogiwara, M; Yoshida, H; Imafuku, Y; Murai, M; Watanabe, K; Uchida, H; Kobayashi, Y; Matsuda, S; Fujime, M; Fujita, K; Igari, J; Oguri, T; Kosakai, N; Yamaguchi, K; Matsumoto, T; Kashitani, F; Mochida, C

    1997-04-01

    Susceptibilities to various antimicrobial agents were examined for Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa that were isolated from patients with urinary tract infections (UTIs) in 11 hospitals during June, 1995 through May, 1996, and the results were compared with those obtained during the same period in earlier years. 1. Macrolide resistant E. faecalis isolated from uncomplicated UTIs during the latest study period appeared to have increased compared to those in previous study periods. More than 50% of the isolated E. faecalis during the latest study period were resistant to macrolide antibiotics, for the first time in our history. 2. No obvious changes were observed through the years for susceptibilities of S. aureus to various antimicrobial agents. Vancomycin (VCM) showed the highest activity against S. aureus, with MICs below 2 micrograms/ml or below. 3. Among E. coli strains, those with low susceptibilities to quinolones appeared to have increased over the years with MIC90 changed from between 0.125 microgram/ml or below and 0.5 microgram/ml in the 1989-1990 period to between 8 micrograms/ml and 128 micrograms/ml in the latest study period. 4. Klebsiella spp. showed higher resistance to most antimicrobial agents during periods of 1993-1994 and 1994-1995, but somewhat lower resistance during period of 1995-1996. No resistant Klebsiella spp. were detected from uncomplicated UTIs during the latest study period. 5. Among P. aeruginosa isolates from complicated UTIs, resistance isolates to gentamicin appeared to be increasing over the years. Resistant strains to quinolones were isolated at lower frequencies during periods of 1991-1994, but higher frequency was observed in the latest period, and MIC50s were between 0.5 and 4 micrograms/ml during 1991-1994, but were 16-32 micrograms/ml during 1995-1996. These susceptibility changes should be utilized in determining clinical treatments. PMID:9192248

  3. Update of contemporary antimicrobial resistance rates across China: reference testing results for 12 medical centers (2011).

    Science.gov (United States)

    Jones, Ronald N; Castanheira, Mariana; Hu, Bijie; Ni, Yuxing; Lin, Stephen S F; Mendes, Rodrigo E; Wang, Yao

    2013-11-01

    Antimicrobial resistance (R) surveillance across Asia and especially in China has documented unique patterns and mechanisms. This 2011 study reports results for 2278 isolates from 12 hospitals in China (94-216 strains/site); most from bacteremia (20.4%), pneumonias (29.1%), or skin and skin structure infections (20.9%). Samples were tested by reference broth microdilution methods, interpreted by published susceptibility (S) breakpoints. The most common species were Staphylococcus aureus (343, 45.8% MRSA), Escherichia coli (EC; 288), Pseudomonas aeruginosa (PSA; 221), Klebsiella spp. (KSP; 208), acinetobacters (ACB; 178), enterobacters (155), Streptococcus pneumoniae (SPN; 154, 46.8% penicillin-S), and enterococci (ENT; 137). Among 849 Gram-positive (GP) cocci, linezolid, tigecycline (TIG), daptomycin, and vancomycin provided best antimicrobial coverage (≥99.7% S). Resistance patterns of concern were 0.3% VISA, 15.4% teicoplanin non-S coagulase-negative staphylococci, 1.5% vancomycin-R ENT (all Enterococcus faecium), 1.9% levofloxacin-R β-haemolytic streptococci, and 35.1 and 12.7% ceftriaxone-non-S rates for SPN and viridans group streptococci, respectively. For Gram-negative bacilli, R among Enterobacteriaceae was highest against β-lactams (extended spectrum β-lactamase-phenotype strains at 73.6 and 42.8% in EC and KSP, respectively; carbapenem-R was only 2.1-4.3% with KPC and IMP type enzymes detected in KSP). The widest spectrum agents were cefoperazone/sulbactam (79.5-86.1%), piperacillin/tazobactam (88.9-92.0%), TIG (98.6-100%), amikacin (AMK; 91.8-93.7%), and meropenem (95.7-97.1% S). PSA was most inhibited by AMK (90.5% S) and colistin (COL; 99.5%), with cefepime (67.9%) best among the tested β-lactams. Only COL (100% S) and TIG (MIC90, 2 μg/mL) showed significant potencies against ACB. In conclusion, R among pathogens from 12 Chinese hospitals illustrates several agents active against GP pathogens, but more serious R problems were noted among

  4. Multilaboratory evaluation of an agar diffusion disk susceptibility test for rapidly growing anaerobic bacteria.

    Science.gov (United States)

    Barry, A L; Fuchs, P C; Gerlach, E H; Allen, S D; Acar, J F; Aldridge, K E; Bourgault, A M; Grimm, H; Hall, G S; Heizmann, W

    1990-01-01

    A multilaboratory collaborative study was undertaken to determine whether the anaerobic disk diffusion test of Horn et al. could be performed reproducibly and accurately. Tests with nine different antimicrobial disks were evaluated. Reproducibility of the agar diffusion disk method was similar to that of the reference agar dilution test procedure. The anaerobic disk diffusion procedure was found to be a potentially useful method for testing some antimicrobial agents against rapidly growing anaerobes belonging to the Bacteroides fragilis group. These promising results warrant further investigations and validations. PMID:2406872

  5. BACTERIAL FLORA OF HATCHERY ENVIRONMENT AND THEIR IN-VITRO SUSCEPTIBILITY TO ANTIMICROBIAL AGENTS

    Directory of Open Access Journals (Sweden)

    F. M. Khan, H. Afzal and F. Deeba

    2003-04-01

    Full Text Available Four hatcheries, located in and around Faisalabad, were sampled a day before hatch out in six batches for environmental bacterial flora. Hatchery air, egg-shell surface, surfaces of selected locations and water supply samples were taken for this purpose. The percent (relative occurrence of various bacterial species recovered from hatchery environment revealed that Bacillus subtilis was the predominant isolate (26.93%. followed by Escherichia coli (24.08%, Staphylococcus epidermidis (16.32%, Staphylococcus aureus (8.16%, Paratyphoid salmonellae (6.93%, Pseudomonas aeruginosa (4.48%, Citrobacter jreundii (4.08%, Enterococcus faecalis (3.26%, Klebsiella pneumoniae (3.26%, Bordetella avium (1.63% and Proteus vulgaris (0.81%. In second part of the study, bacterial isolates were subjected to in-vitro antibiotic sensitivity to 8 antibiotics of common poultry use. It was found that 98.92, 79.56. 65.59, 61.29, 61.29, 61.29, 53.76 and 38.70 percent of bacterial isolates were sensitive to Norfloxacin, Gentamicin, Neomycin, Chloramphenicol, Doxycycline, Flumequine, Erythromycin, and Ampicillin, respectively. In the final part of the study, bacterial isolates were tested for resistance to 3 commerical hatchery disinfectants (TH4®, Aldekol Des® 0.2, and Bromosept 10% soln. ®. Only 3.22% of the isolates showed resistance at manufacturer's recommended dilution (MRD levels while 11.82% of the isolates showed resistance at concentrations below the MRD levels.

  6. Evaluation of antifungal susceptibility testing in Candida isolates by Candifast and disk-diffusion method

    OpenAIRE

    Sidhartha Giri; Anupma Jyoti Kindo

    2014-01-01

    With the increase in invasive fungal infections due to Candida species and resistance to antifungal therapy, in vitro antifungal susceptibility testing is becoming an important part of clinical microbiology laboratories. Along with broth microdilution and disk diffusion method, various commercial methods are being increasingly used for antifungal susceptibility testing, especially in the developed world. In our study, we compared the antifungal susceptibility patterns of 39 isolates of Candid...

  7. Antifungal susceptibility testing of Aspergillus species complex in the Clinical Laboratory: how to do it, when to do it, and how to interpret it

    Directory of Open Access Journals (Sweden)

    Esther Manso

    2014-12-01

    Full Text Available The emergence of drug resistance in fungal pathogens has a profound impact on human health given limited number of antifungal drugs. Antifungal resistance in Aspergillus spp. infection can be encountered in the antifungal drug-exposed patient due to selection of intrinsically resistant species or isolates with acquired resistance belonging to species that are normally susceptible. Resistance to triazoles is not common in Aspergillus spp., however, triazole resistance in A. fumigatus appears to be increasing in several European countries in recent years and can be clinically relevant. The Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing have developed breakpoints and epidemiological cutoff values that are now established for Aspergillus spp. Clinical microbiology laboratories will be employed commercial susceptibility assays, rather than reference broth microdilution methods and comparative studies are particularly important.

  8. Isolation and antimicrobial susceptibility of Campylobacter in pig%猪源弯曲菌的分离鉴定及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    许紫建; 杨兵; 覃湘婕; 苏霞; 史爱华; 陈小玲; 孙继国; 徐福洲

    2013-01-01

    目的 为调查猪肠道内空肠弯曲菌和结肠弯曲菌的流行和耐药性状况.方法 本试验自北京郊区养猪场和屠宰场采集猪肠道粪便样品,经增菌培养后利用三重PCR进行弯曲菌属、空肠弯曲菌和结肠弯曲菌的检测,进而对PCR检测阳性样品进行弯曲菌的分离鉴定,最后对分离鉴定的弯曲菌分离株进行药敏试验鉴定.结果 本试验共采集猪肠道和肛门棉拭子样品241份,PCR检测结肠弯曲菌阳性样品数为178份,阳性率为73.9%,而空肠弯曲菌阳性样品数5份,阳性率仅为2.1%.经分离鉴定后共获得结肠弯曲菌菌株63株,分离率为35.4%,未分离获得空肠弯曲菌菌株.对26种抗生素的药敏试验结果显示结肠弯曲菌分离株对氯霉素(100%)、丁胺卡那(93.65%)、强力霉素(91.48%)、庆大霉素(82.54%)和阿莫西林(82.54%)等抗生素比较敏感,而对头孢哌酮(100%)、头孢氨苄(100%)、头孢拉啶(100%)、头孢唑啉(98.41%)、头孢克肟(92.06%)、萘啶酸(92.06%)、链霉素(90.48%)、环丙沙星(90.32%)、诺氟沙星(88.89%)和青霉素(87.30%)具有显著的耐药性;而且分离株多重耐药现象比较普遍,主要集中于14-20耐.结论 本试验结果显示猪肠道内普遍存在结肠弯曲菌,而且菌株对多种抗生素产生了显著的耐药性.%To investigate prevalence and antimicrobial susceptibility of Campylobacter jejuni and Campylobacter coli in pig gut, samples from Beijing suburban pig farms and slaughter house were collected for Campylobacter isolation . After enrichment, the samples were simultaneously examined for the genus Campylobacter, the species of C. jejuni and C. coliby triplex PCR. Isolation and identification of Campylobacter strains were performed from the PCR-based positive samples . Finally , the Campylobacter isolates were tested for antibiotic resistance by antimicrobial susceptibility assay . In this study , a total of 241 samples of pig intestinal contents and anal

  9. Aerobic bacteria from mucous membranes, ear canals, and skin wounds of feral cats in Grenada, and the antimicrobial drug susceptibility of major isolates.

    Science.gov (United States)

    Hariharan, Harry; Matthew, Vanessa; Fountain, Jacqueline; Snell, Alicia; Doherty, Devin; King, Brittany; Shemer, Eran; Oliveira, Simone; Sharma, Ravindra N

    2011-03-01

    In a 2-year period 54 feral cats were captured in Grenada, West Indies, and a total of 383 samples consisting of swabs from rectum, vagina, ears, eyes, mouth, nose and wounds/abscesses, were cultured for aerobic bacteria and campylobacters. A total of 251 bacterial isolates were obtained, of which 205 were identified to species level and 46 to genus level. A commercial bacterial identification system (API/Biomerieux), was used for this purpose. The most common species was Escherichia coli (N=60), followed by Staphylococcus felis/simulans (40), S. hominis (16), S. haemolyticus (12), Streptococcus canis (9), Proteus mirabilis (8), Pasteurella multocida (7), Streptococcus mitis (7), Staphylococcus xylosus (7), S. capitis (6), S. chromogenes (4), S. sciuri (3), S. auricularis (2), S. lentus (2), S. hyicus (2), Streptococcus suis (2) and Pseudomonas argentinensis (2). Sixteen other isolates were identified to species level. A molecular method using 16S rRNA sequencing was used to confirm/identify 22 isolates. Salmonella or campylobacters were not isolated from rectal swabs. E. coli and S. felis/simulans together constituted 50% of isolates from vagina. S. felis/simulans was the most common species from culture positive ear and eye samples. P. multocida was isolated from 15% of mouth samples. Coagulase-negative staphylococci were the most common isolates from nose and wound swabs. Staphylococcus aureus, or S. intemedius/S. pseudintermedius were not isolated from any sample. Antimicrobial drug resistance was minimal, most isolates being susceptible to all drugs tested against, including tetracycline. PMID:20627391

  10. Streptococcus agalactiae em gestantes: prevalência de colonização e avaliação da suscetibilidade aos antimicrobianos Streptococcus agalactiae in pregnant women: prevalence of colonization and antimicrobial susceptibility evaluation

    Directory of Open Access Journals (Sweden)

    Irina Lermontov Borger

    2005-10-01

    Full Text Available OBJETIVOS: verificar a ocorrência de colonização por Streptococcus agalactiae em gestantes e avaliar a suscetibilidade das amostras isoladas aos antimicrobianos. MÉTODOS: foram avaliadas 167 grávidas entre a 32ª e a 41ª semana de gestação, independente da presença ou não de fatores de risco, atendidas no ambulatório de pré-natal entre fevereiro de 2003 e fevereiro de 2004. O material vaginal/anal, colhido com um único swab, foi inoculado em caldo Todd-Hewitt acrescido de ácido nalidíxico (15 µg/mL e gentamicina (8 µg/mL, com posterior subcultura no meio de ágar sangue. A identificação foi feita por meio da avaliação da morfologia e tipo de hemólise das colônias no meio de ágar sangue, teste da catalase, teste de cAMP e testes sorológicos. A avaliação da suscetibilidade aos antimicrobianos foi realizada pelos testes de difusão e de diluição em ágar. A análise estatística foi realizada por meio do teste de chi2; valores de p0,05. Todas as 32 amostras isoladas foram sensíveis a penicilina, cefotaxima, ofloxacina, cloranfenicol, vancomicina e meropenem. A resistência a eritromicina e clindamicina foi detectada em 9,4 e 6,2% das amostras, respectivamente. CONCLUSÕES: a incidência relativamente elevada (19,2% de colonização por S. agalactiae entre as gestantes avaliadas e o isolamento de amostras resistentes, especialmente aos antimicrobianos recomendados nos casos de alergia à penicilina, enfatizam a importância de detectar esta colonização no final da gravidez, associada à avaliação da suscetibilidade aos antimicrobianos, para uma prevenção eficaz da infecção neonatal.PURPOSE: to verify the occurrence of colonization by Streptococcus agalactiae in pregnant women attended at the prenatal outpatient clinic of the Teaching Maternity Hospital of Rio de Janeiro University (UFRJ and to evaluate the susceptibility of the isolates to antimicrobial agents. METHODS: a total of 167 pregnant women between the

  11. AEROMONAS SPP BACTEREMIA OF RAINBOW TROUT FRY (ONCORHYNCHUS MYKISS: BIOCHEMICAL CHARACTERIZATION OF THE CAUSATIVE ORGANISM AND ANTIMICROBIAL SUSCEPTIBILITY

    Directory of Open Access Journals (Sweden)

    Damir Kapetanović

    2004-09-01

    Full Text Available Aeromonas hydrophila and other members of Aeromonas genus are ubiquitus in aquatic environment and make part of normal bacterial flora of rainbow trout. Aeromonas spp. infections are worldwide registered. Here we present our experience and knowledge on Aeromonas bacteremia, which causes mortality of rainbow trout fry. Rainbow trout fry, 7 month old, started to die in November 2003. Fish samples (17 samples of dead and moribund fish were delivered to the Laboratory for aquaculture. With Api 20 NE tests Aeromonas hydrophila / caviae type I was identified with an average probability of 99.9 % (one test against, as well as Aeromonas hydrophila / caviae type II with an average probability of 99.5 % (one test against from liver, spleen, kidney, intestines and damaged eye. All of isolated and identified samples were tested for antibiotic susceptibility by disc diffusion method. The test showed that specimens were most sensitive on flumequin, and relatively less sensitive on chloramphenicol and enrofloxacin. Therapy was successfully applied with Flubactin®.

  12. Antimicrobial susceptibility of communityacquired respiratory tract pathogens isolated from patients in primary hospitals in Shanghai from 2007 to 2010

    Institute of Scientific and Technical Information of China (English)

    周春妹

    2013-01-01

    Objective To investigate the etiology of communityacquired respiratory tract infections (CARTI) and the antimicrobial resistance of the major pathogens in primary hospitals in Shanghai.Methods Patients with CARTI were prospectively recruited from 30 primary hospitals

  13. Neisseria gonorrhoeae antimicrobial susceptibility in Barcelona: penA, ponA, mtrR, and porB mutations and NG-MAST sequence types associated with decreased susceptibility to cephalosporins.

    Science.gov (United States)

    Serra-Pladevall, J; Barberá, M J; Rodriguez, S; Bartolomé-Comas, R; Roig, G; Juvé, R; Andreu, A

    2016-09-01

    The aims of this study were to determine the antimicrobial susceptibility of Neisseria gonorrhoeae (NG) in our area, to analyze the molecular mechanisms involved in cephalosporins resistance, and to undertake molecular typing of our NG strains. Antimicrobial susceptibility was determined using the Etest. The genes penA, mtrR, penB, and ponA were studied. Molecular typing was performed by N. gonorrhoeae multiantigen sequence typing. Of 329 strains analyzed in 2013, none showed high-level cephalosporin resistance, but 8.2 % had resistance to cefixime [minimum inhibitory concentration (MIC) > 0.125 μg/mL] and 0.6 % to ceftriaxone (MIC > 0.125 μg/mL). Azithromycin resistance was documented in 4.3 % and ciprofloxacin resistance in 49.2 %. Among 48 strains with an MIC ≥ 0.125 μg/mL to cefixime, 58.3 % showed the penA mosaic pattern XXXIV, 98 % a Leu → Pro substitution at position 421 of the ponA gene, 100 % amino acid changes at positions 101 and 102 of the PorB1b porin, and 87.5 % of strains an adenine deletion in the promoter region of the MtrC-D-E efflux pump. A significant difference between strains with and without decreased cephalosporin susceptibility (MIC ≥ 0.125 μg/mL) was observed for these four genes. Of the 48 strains with an MIC ≥ 0.125 μg/mL to cefixime, 43.8 % belonged to the genogroup G1407 and 27.1 % belonged to the genogroup G2400. A significant association of G1407 with decreased susceptibility (MIC ≥ 0.125 μg/mL) and G2992 with susceptibility was found, and also between G1407 and mosaic pattern XXXIV and between G2400 and A501T substitution in penA. The NG resistance rate in our area is higher than the median of Europe. We have detected the emergence of G2400, which may be a source of antimicrobial resistance. PMID:27255221

  14. Comparison of the serum-supplemented Todd-Hewitt and the new Haemophilus test media for broth microdilution susceptibility testing of Streptococcus pneumoniae.

    Science.gov (United States)

    Roger, M; Lapointe, J R

    1996-06-01

    Horse serum-supplemented Todd-Hewitt broth (STH) in use at Hôpital Ste-Justine for the last 12 years was compared to the recently proposed Haemophilus test medium (HTM), for broth microdilution susceptibility testing of Streptococcus pneumoniae. One hundred and twenty S. pneumoniae isolates from pediatric clinical specimens were used in this study. In general, the minimum inhibitory concentrations (MICs) in STH for 15 antimicrobial agents were quite comparable to those determined in HTM but tended to be higher. Drugs which generated MICs within +/- 1 log2 concentration differences in both media included penicillin, ampicillin, oxacillin, cefuroxime, cefotaxime, cefixime, clindamycin, chloramphenicol, trimethoprim-sulfamethoxazole, rifampin, ciprofloxacin and vancomycin. Cefaclor and tetracycline MICs tended to be > or = 2 log2 dilutions higher with STH for most of the isolates tested, while erythromycin MICs were often 2 log2 dilutions lower with STH than with HTM. Despite some differences in MICs noted above, few very major (0.4%), major (0.2%) and minor interpretive category errors (4.4%) were observed. The visual reading of the MICs for most of the 120 clinical isolates tested was generally easier in STH which was superior in supporting best the bacterial growth as detected by spectrophotometry. The risk of false susceptibility is thus decreased by using STH rather than HTM; furthermore, STH is free of the technical problems of the lysed horse blood Mueller-Hinton (LHB-MH) recommended by the NCCLS. PMID:8808713

  15. Antimicrobial susceptibility of Salmonella serovars isolated from edible offal and carcasses of slaughtered poultry in the state of Tocantins, Brazil

    Directory of Open Access Journals (Sweden)

    Silvia Minharro

    2015-08-01

    Full Text Available The aim of this study was to evaluate the profile of antibiotic resistance in Salmonella isolated from the carcasses, livers and hearts of chickens slaughtered in the state of Tocantins, Brazil, as recommended by the Normative Instruction 70 of 2003 of the Ministry of Agriculture, Livestock and Food Supply and the National Monitoring Program Prevalence and Bacterial Resistance in Chicken. Carcasses, livers and hearts from chicken with or without pericarditis/perihepatitis were studied in 60 lots of poultry slaughtered under the Federal Inspection System in the state of Tocantins, Brazil between August 2010 and June 2011. Twenty-six indicative Salmonella sp. were isolated in 11 lots (18.33%. Different strains of Salmonella were isolated more than a kind of sample/lot. The most frequent serovar was Enteriditis (38.46%, 10/26, while the second was Mbandaka (19.23%, 5/26, both isolated from hearts, livers and carcasses. Regarding antimicrobial resistance, of 12 tested principal pharmacological agents, the samples appeared to be most sensitive to tetracyclines, but showed 100% resistance to one or more active principal agents, especially sulfamethoxazole (30 mcg and amoxicillin/clavulanic acid (30 mcg. Although Salmonella sp. was isolated from normal carcasses, the results are within permitted levels for unfrozen products according to Brazilian legislation. However, one should always be aware of the hygienic and sanitary conditions of production processes and food processing, especially regarding good manufacturing practices.

  16. 铜绿假单胞菌对亚胺培南的耐药水平调查及药敏分析%Surveillance on Resistant Level of Pseudomonas aerginosa to Imipenem and Analysis of Antimicrobial Susceptibility

    Institute of Scientific and Technical Information of China (English)

    廖文安; 龚燕飞; 刘湘林

    2011-01-01

    Objective To survey the imipenem (IMP) resistance of Pseudomonas aeruginosa isolated from the hospitalized patients in the First People's Hospital of Yueyang from March 2009 to July 2010, and to analyze antimicrobial susceptibility of imipenern- resistant strains. Methods The MIC values of resistance of Pseudomonas aeruginosa to IMP and other 9 antimicrobial agents were tested by agar- plating diluted technique. Results The resistant rate to IMP resistance of Pseudomonas aeruginosa was 13.5 %, 20 strains of Pseudomonas aeruginosa resistant to IMP also had a higher resistance to other 9 antimicrobial agents. 2 strains isolated were resistant to the total 10 antimicrobial agents. Conclusions Pseudomonas aeruginosa not only has a high resistance to IMP but also has a resistance to many antimicrobial agents. It is necessary to pay close attention to the bacterial resistance changes and to adjustment of treatment plans at the right moment in order to use antimicrobial agents rationally.%目的 了解2009年3月-2010年7月岳阳市一人民医院住院患者送检标本分离的铜绿假单胞菌对亚胺培南的耐药水平,并分析亚胺培南耐药株对其他常用抗菌药物的耐药性.方法 临床标本分离的铜绿假单胞菌用常规K-B法进行药物敏感试验,若结果判定为耐药和中介,则进一步采用琼脂倍比稀释法检测铜绿假单胞菌对亚胺培南及其他9种抗菌药物的MIC.结果 铜绿假单胞菌对亚胺培南的耐药率为13.5%,20株耐亚胺培南的铜绿假单胞菌对9种常用抗菌药物的耐药率也普遍较高,有2株铜绿假单胞菌对受试的10种抗菌药物全部耐药.结论 铜绿假单胞菌对亚胺培南的耐药率较高,并对多种抗菌药物耐药,应密切关注本地区细菌耐药性的变迁,适时调整治疗方案,合理应用抗菌药物.

  17. Antimicrobial susceptibility and Ribosomal-RNA gene restriction patterns among Staphylococcus-intermedius from healthy dogs and from dogs sufferning from pyoderma or otitis-externa

    DEFF Research Database (Denmark)

    Pedersen, Karl; Wegener, Henrik Caspar

    1995-01-01

    10 strains from a previous study. Sixty per cent of the 50 strains tested for antibiotic susceptibility demonstrated resistance to penicillin, 24% to spiramycin, 20% to tetracycline, 16% to chloramphenicol, and 2% to fucidic acid, All isolates were susceptible to amoxycillin with clavulanic acid...

  18. Serotype distribution and antimicrobial susceptibilities of Streptococcus agalactiae isolated from infected cultured tilapia (Oreochromis niloticus) in Thailand: Nine-year perspective.

    Science.gov (United States)

    Dangwetngam, Machalin; Suanyuk, Naraid; Kong, Fanrong; Phromkunthong, Wutiporn

    2016-03-01

    Streptococcus agalactiae (group B Streptococcus, GBS) infection remains a major problem associated with high mortality of cultured tilapia worldwide. The present study reports the serotype distribution and antimicrobial susceptibilities of GBS isolated from infected tilapia cultured in Thailand. One hundred and forty-four GBS isolates were identified by biochemical, serological and molecular analyses. Of these 144 GBS isolates, 126 were serotype Ia and 18 were serotype III. Antimicrobial susceptibilities of the 144 GBS isolates were determined by the disc diffusion method. Most GBS isolates were susceptible to lincomycin, norfloxacin, oxytetracycline, ampicillin, erythromycin and chloramphenicol, but resistant to oxolinic acid, gentamicin, sulfamethoxazole and trimethoprim. However, 17 isolates displayed an oxytetracycline-resistant phenotype and harboured the tet(M) gene. The broth microdilution method was used to determine the minimal inhibitory concentrations (MICs) of 17 oxytetracycline-resistant GBS isolates, and then minimal bactericidal concentrations (MBCs) of these isolates were evaluated. Oxytetracyline-resistant isolates were found to be susceptible to ampicillin, lincomycin, norfloxacin, erythromycin and chloramphenicol, with the MIC and MBC ranging from ≤ 0.125 to 0.5 μg ml- 1 and ≤ 0.125 to 2 μg ml- 1, respectively. Moreover, all 17 oxytetracycline-resistant isolates demonstrated resistance to trimethoprim, oxolinic acid, gentamicin, sulfamethoxazole and oxytetracycline, with the MIC and MBC ranging from 16 to ≥ 128 μg ml- 1 and ≥ 128 μg ml- 1, respectively. These findings are useful information for antibiotic usage in fish aquaculture. PMID:26701807

  19. Multicenter Survey of Routine Determinations of Resistance of Helicobacter pylori to Antimicrobials over the Last 20 Years (1990 to 2009) in Belgium▿

    OpenAIRE

    Deyi, V. Y. Miendje; Bontems, P.; Vanderpas, J.; De Koster, E.; Ntounda, R.; Van den Borre, C; Cadranel, S; Burette, A

    2011-01-01

    We analyzed the rates of antimicrobial resistance of Helicobacter pylori strains isolated from patients from 1990 to 2009 and identified risk factors associated with resistance. Gastric biopsy specimens were collected from several digestive disease centers in Brussels, Belgium. We routinely performed antimicrobial susceptibility testing for clarithromycin (CLR), metronidazole, amoxicillin, tetracycline, and ciprofloxacin. Evaluable susceptibility testing was obtained for 9,430 strains isolate...

  20. Test of Fuzzy Logic Rules for Landslide Susceptibility Assessment

    OpenAIRE

    Thiery, Yannick; Malet, Jean-Philippe; Maquaire, Olivier

    2006-01-01

    Landslide Susceptibility Assessment (LSA) is defined as the spatial probability for a landslide to be generated in an area for many environmental factors. Currently, two approaches are used: (i) the qualitative approach based on expert opinion and knowledge of the relationship between the observed phenomenon and some predisposing factors and (ii) the statistical approach based on the statistical analysis of the relationship between the observed landslide and some predisposing factors. This pa...

  1. TESTING ANTIMICROBIAL PAINT EFFICACY ON GYPSUM WALLBOARD CONTAMINATED WITH STACHYBOTRYS CHARTARUM

    Science.gov (United States)

    Often mold contaminated building materials are not properly removed, some surface cleaning is performed and paint is applied in an attempt to alleviate the problem. The efficacy of antimicrobial paints to eliminate or control mold regrowth on surfaces can easily be tested on non-...

  2. TESTING ANTIMICROBIAL CLEANER EFFICACY ON GYPSUM WALLBOARD CONTAMINATED WITH STACHYBOTRYS CHARTARUM

    Science.gov (United States)

    Reducing occupant exposure to indoor mold growth is the goal of this research, through the efficacy testing of antimicrobial cleaners. Often mold contaminated building materials are not properly removed, but instead surface cleaners are applied in an attempt to alleviate the prob...

  3. Isolation, cultivation, and in vitro susceptibility testing of Borrelia burgdorferi sensu lato: A review

    Directory of Open Access Journals (Sweden)

    Veinović Gorana

    2013-01-01

    Full Text Available Lyme borreliosis is the most common vector-borne disease in the northern hemisphere. The agents of Lyme borreliosis are borrelia, bacteria of the family Spirochaetaceae, which are grouped in Borrelia burgdorferi sensu lato species complex. Borreliae are fastidious, slow-growing and biochemically inactive bacteria that need special attention and optimal conditions for cultivation. The isolation of Borrelia from clinical material and their cultivation is a time-consuming and demanding procedure. Cultivation lasts from 9 up to 12 weeks, which is much longer than is necessary to grow most other human bacterial pathogens. Although B. burgdorferi sensu lato is susceptible to a wide range of antimicrobial agents in vitro, up to now the susceptibility of individual Borrelia species to antibiotics is defined only partially. [Projekat Ministarstva nauke Republike Srbije, br. 175011

  4. Use of a constant deflection test to evaluate susceptibility to irradiation-assisted stress corrosion cracking

    International Nuclear Information System (INIS)

    A constant deflection test was developed to evaluate the susceptibility of irradiated stainless steel (SS) to irradiation-assisted stress corrosion cracking. The test was shown useful in supplementing constant extension rate tensile or slow strain rate tensile, constant load, and swelling mandrel tests that have been used in the past. Preliminary data showing the susceptibility of commercial-purity type 304 SS (UNS S30400) as a function of stress, strain, and fast neutron fluence (E > 1 MeV) were presented

  5. Change in Antimicrobial Susceptibility of Skin-Colonizing Staphylococcus aureus in Korean Patients with Atopic Dermatitis during Ten-Year Period

    Science.gov (United States)

    Park, Jung-Min; Jo, Ju-Hyun; Jin, Hyunju; Ko, Hyun-Chang; Kim, Moon-Bum; Kim, Jung-Min; Kim, Do-Won; Jang, Ho-Sun

    2016-01-01

    Background A small subset of adolescents atopic dermatitis (AD) tends to persist. This also leads to get more antibiotics exposure with advancing years. Antibiotic resistance has been regarded as a serious problem during Staphylococcus aureus treatment, especially methicillin-resistant S. aureus (MRSA). Objective It was investigated the S. aureus colonization frequency in the skin lesions and anterior nares of adolescent AD patients and evaluated the changes in S. aureus antimicrobial susceptibility for years. Methods Patients who visited our clinic from September 2003 to August 2005 were classified into group A, and patients who visited from August 2010 to March 2012 were classified into group B. To investigate the differences with regard to patients' age and disease duration, the patients were subdivided into groups according to age. Lesional and nasal specimens were examined. Results Among the 295 AD patients, the total S. aureus colonization rate in skin lesions was 66.9% (95/142) for group A and 78.4% (120/153) for group B. No significant changes in the systemic antimicrobial susceptibilities of S. aureus strains isolated from adolescent AD patients were observed during about 10-year period. The increased trend of MRSA isolation in recent adolescent AD outpatients suggest that the community including school could be the source of S. aureus antibiotic resistance and higher fusidic acid resistance rates provides evidence of imprudent topical use. Conclusion Relatively high MRSA isolation and fusidic acid resistance rates in recent AD patients suggest that the community harbors antibiotic-resistant S. aureus. PMID:27489430

  6. Antimicrobial susceptibility pattern and SCCmec types of methicillin-resistant coagulase-negative staphylococci from subclinical bovine mastitis in Hatay, Turkey

    Directory of Open Access Journals (Sweden)

    Aslantaş Özkan

    2014-12-01

    Full Text Available Eighty-nine isolates of coagulase-negative staphylococci (CoNS of eight species from subclinical bovine mastitis were screened for the phenotypic and genotypic methicilline-resistance. In addition, all methicillin-resistant (MR isolates indicating the mecA gene were examined by PCR for the antimicrobial susceptibility patterns, and staphylococcal cassette chromosome mec (SCCmec types were also determined by multiplex PCR. A total of 21 (23.6% CoNS isolates were found to be resistant to oxacillin in broth microdilution assay. All isolates phenotypically resistant to oxacillin did not have the mecA gene, which was only found in 14.6% (13 of the isolates. Most MR-CoNS isolates were highly resistant to erythromycin (92.3%, fusidic acid (84.6%, penicillin (76.9%, and rifampycin (61.5%, and susceptible to mupirocin (100%, tetracycline (100%, vancomycin (100%, clindamycin (92.3%, and sulfamethoxazole-trimethoprim (69.2%. In conclusion, a high rate of antimicrobial resistance among MR-CoNS isolated from food producing animals emphasises the need for periodic surveillance of their resistance.

  7. Isolation and species identification of enterococci from clinical specimen with their antimicrobial susceptibility pattern in a tertiary care hospital, Bangladesh

    Directory of Open Access Journals (Sweden)

    Tashmin Afroz Binte Islam

    2015-10-01

    Full Text Available Objective: To investigate the species prevalence of Enterococcus with their antimicrobial resistance pattern from patients of Dhaka Medical College Hospital. Methods: Samples were cultured and Enterococcus species were identified by conventional biochemical tests as well as PCR by using species specific primers for Enterococcus faecalis (E. faecalis and Enterococcus faecium (E. faecium. For isolation of vancomycin resistant enterococci, minimum inhibitory concentration of vancomycin and PCR was done to detect vanA and vanB genes. Results: A total of 16 enterococci were isolated from 300 urine and 200 wound swab samples (15 from urine and 1 from wound swab from July 2011 to June 2012. Enterococci were the third most common organism (8.47% from urine after Escherichia coli (63.28% and Enterobacter (11.87%. Out of 16 enterococci, 10 (62.5% were E. faecalis, 4 (25% were E. faecium and 2 (12.5% were other species. All the enterococci (100% were sensitive to vancomycin and linezolid. Most of the strains were resistant to ciprofloxacin and azithromycin (87.5%, gentamycin (81.25%, ceftriaxone (75%, amoxiclav (31.25% and imipenem (25%. E. faecium was more resistant than E. faecalis to azithromycin (100%, ciprofloxacin (100%, amoxiclav (75% and imipenem (50%. No vancomycin resistant enterococci were identified and the range of minimum inhibitory concentration for vancomycin was 1–4 µg/mL. None of the enterococci were positive for vanA and vanB genes. Conclusions: The presence of multidrug resistant enterococci should be considered as danger alarm for serious enterococcal infections and further study in large scale is needed.

  8. The health and economic burden of bloodstream infections caused by antimicrobial-susceptible and non-susceptible Enterobacteriaceae and Staphylococcus aureus in European hospitals, 2010 and 2011: a multicentre retrospective cohort study.

    Science.gov (United States)

    Stewardson, Andrew J; Allignol, Arthur; Beyersmann, Jan; Graves, Nicholas; Schumacher, Martin; Meyer, Rodolphe; Tacconelli, Evelina; De Angelis, Giulia; Farina, Claudio; Pezzoli, Fabio; Bertrand, Xavier; Gbaguidi-Haore, Houssein; Edgeworth, Jonathan; Tosas, Olga; Martinez, Jose A; Ayala-Blanco, M Pilar; Pan, Angelo; Zoncada, Alessia; Marwick, Charis A; Nathwani, Dilip; Seifert, Harald; Hos, Nina; Hagel, Stefan; Pletz, Mathias; Harbarth, Stephan

    2016-08-18

    We performed a multicentre retrospective cohort study including 606,649 acute inpatient episodes at 10 European hospitals in 2010 and 2011 to estimate the impact of antimicrobial resistance on hospital mortality, excess length of stay (LOS) and cost. Bloodstream infections (BSI) caused by third-generation cephalosporin-resistant Enterobacteriaceae (3GCRE), meticillin-susceptible (MSSA) and -resistant Staphylococcus aureus (MRSA) increased the daily risk of hospital death (adjusted hazard ratio (HR) = 1.80; 95% confidence interval (CI): 1.34-2.42, HR = 1.81; 95% CI: 1.49-2.20 and HR = 2.42; 95% CI: 1.66-3.51, respectively) and prolonged LOS (9.3 days; 95% CI: 9.2-9.4, 11.5 days; 95% CI: 11.5-11.6 and 13.3 days; 95% CI: 13.2-13.4, respectively). BSI with third-generation cephalosporin-susceptible Enterobacteriaceae (3GCSE) significantly increased LOS (5.9 days; 95% CI: 5.8-5.9) but not hazard of death (1.16; 95% CI: 0.98-1.36). 3GCRE significantly increased the hazard of death (1.63; 95% CI: 1.13-2.35), excess LOS (4.9 days; 95% CI: 1.1-8.7) and cost compared with susceptible strains, whereas meticillin resistance did not. The annual cost of 3GCRE BSI was higher than of MRSA BSI. While BSI with S. aureus had greater impact on mortality, excess LOS and cost than Enterobacteriaceae per infection, the impact of antimicrobial resistance was greater for Enterobacteriaceae. PMID:27562950

  9. TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE AND FOSFOMYCIN SUSCEPTIBILITY RATES IN UNCOMPLICATED URINARY TRACT INFECTIONS: TIME TO CHANGE THE ANTIMICROBIAL PREFERENCES.

    Science.gov (United States)

    Guneysel, Ozlem; Suman, Enes; Ozturk, Tuba Cimilli

    2016-03-01

    Urinary tract infections (UTIs) are among the most common bacterial infections in adult population. They are prevalent in all age groups both in women and men. Also, UTIs are the most frequent indication for empirical antibiotic treatment in emergency department. The aim of this study was to determine the antibiotic resistance rates in the treatment of uncomplicated UTIs. Adult patients admitted to emergency department with uncomplicated UTIs were included in this cross-sectional study. Mid-stream urine samples were obtained under sterile conditions and cultured quantitatively. After 24 hours, the samples showing 10(5) colony forming unit per milliliter (CFU/mL) were tested for antibiotic susceptibility. Resistance to fosfomycin-trometamol (FT), amoxicillin-clavulanic acid (AC), ciprofloxacin (CIP), trimethoprim-sulfamethoxazole (TMP-SMX) and cefpodoxime (CEF) was tested by Kirby-Bauer disc diffusion system. Escherichia (E.) coli accounted for the vast majority (93.4%) of the organisms isolated in the study. Among the E. coli positive patients, resistance to TMP-SMX was the most common antibiotic resistance. The E. coli species detected in our study group were least resistant to FT (2.4%). The resistance rates, especially to CEF, AC and CIP, were significantly higher in patients over 50 years of age. In conclusion, in the treatment of uncomplicated UTIs, TMP-SMX should be excluded from empirical treatment, while fosfomycin could be a viable option in all age groups. PMID:27333718

  10. Prevalence, antimicrobial susceptibility and molecular typing of Methicillin-Resistant Staphylococcus aureus (MRSA) in bulk tank milk from southern Italy.

    Science.gov (United States)

    Parisi, A; Caruso, M; Normanno, G; Latorre, L; Sottili, R; Miccolupo, A; Fraccalvieri, R; Santagada, G

    2016-09-01

    This paper assesses the prevalence of MRSA in bulk tank milk (BTM) samples from southern Italy, and the relationship between the Coagulase Positive Staphylococci count (CPS) and MRSA prevalence. Of 486 BTM samples tested, 12 samples (2.5%) resulted positive for the presence of MRSA. Great genetic diversity was found among the isolates: ST1/t127 and t174/IVa, ST5/t688/V, ST8/t unknown/IVa/V, ST45/t015/IVa, ST71/t524/V, ST88/t786/Iva, ST398/t011 and t899/IVa/V and ST2781/t1730/V. All isolates were pvl-negative and icaA positive. The majority of strains (58%) carried the ses (sec, seh, seg, seo, sem and sen) genes. All tested strains resulted susceptible to amikacin, cephalotin, cloramphenicol, gentamycin, trimethoprim - sulfamethoxazole, tobramycin and vancomycin, and variably resistant to ampicillin, oxacillin and tetracycline. No statistical association between the CPS count and MRSA detection was found in the MRSA-positive samples. Although some of the spa-types and STs detected in our survey are known to cause human infections, raw milk from Italian herds in the considered area is not a common source of MRSA. Nonetheless, it is necessary to assess the risk of foodborne infection and the risk related to the handling of milk. PMID:27217357

  11. Antimicrobial resistance trends among canine Escherichia coli isolates obtained from clinical samples in the northeastern USA, 2004–2011

    OpenAIRE

    Cummings, Kevin J.; Aprea, Victor A.; Altier, Craig

    2015-01-01

    Our objectives were to describe the antimicrobial susceptibility of Escherichia coli isolates from dogs in the northeastern USA and to identify temporal trends in resistance to selected antimicrobial agents. Data were collected retrospectively for all canine E. coli isolates from clinical samples submitted to Cornell University’s Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Antimicrobial susceptibility testing was performed on 3519 canine E. coli isolates; fr...

  12. Family system characteristics and psychological adjustment to cancer susceptibility genetic testing : a prospective study

    NARCIS (Netherlands)

    van Oostrom, I.; Meijers-Heijboer, H.; Duivenvoorden, H. J.; Brocker-Vriends, A. H. J. T.; van Asperen, C. J.; Sijmons, R. H.; Seynaeve, C.; Van Gool, A. R.; Klijn, J. G. M.; Tibben, A.

    2007-01-01

    This study examined prospectively the contribution of family functioning, differentiation to parents, family communication and support from relatives to psychological distress in individuals undergoing genetic susceptibility testing for a known familial pathogenic BRCA1/2 or Hereditary nonpolyposis

  13. A Novel Hypoxia Challenge Test Demonstrates Cardiovascular and Pulmonary Susceptibility to Acrolein Gas in Hypertensive Rats.

    Science.gov (United States)

    High levels of air pollution increase the risk of cardiovascular morbidity and mortality, especially in susceptible populations including those with hypertension. Stress tests are useful for manifesting latent effects of exposure, particularly at low concentrations, often when no...

  14. Susceptibility testing of sequential isolates of Aspergillus fumigatus recovered from treated patients.

    NARCIS (Netherlands)

    Danaoui, E.; Meletiadis, J.; Tortorano, A.M.; Symoens, F.; Nolard, N.; Viviani, M.A.; Piens, M.A.; Lebeau, B.; Verweij, P.E.; Grillot, R.

    2004-01-01

    Two-hundred sequential Aspergillus fumigatus isolates recovered from 26 immunocompromised patients with invasive aspergillosis or bronchial colonization were tested for their in vitro susceptibility to posaconazole, itraconazole, voriconazole, terbinafine and amphotericin B. Twenty-one patients were

  15. Antimicrobial Susceptibility of Clinically Relevant Gram-Positive Anaerobic Cocci Collected over a Three-Year Period in the Netherlands

    NARCIS (Netherlands)

    Veloo, A. C. M.; Welling, G. W.; Degener, J. E.

    2011-01-01

    The susceptibility of 14 species of 115 Gram-positive anaerobic cocci (GPAC) was determined for 14 antibiotics. To assure correct identification, strains were genotypically identified by fluorescence in situ hybridization and sequencing. Susceptibility differences (MIC(50) and MIC(90)) for penicilli

  16. Antifungal Susceptibility Testing with Etest for Candida Species Isolated from Patients with Oral Candidiasis

    OpenAIRE

    Song, You Bum; Suh, Moo Kyu; Ha, Gyoung Yim; Kim, Heesoo

    2015-01-01

    Background The necessity of performing antifungal susceptibility tests is recently increasing because of frequent cases of oral candidiasis caused by antifungal-resistant Candida species. The Etest (BioMerieux, Marcy l'Etoile, France) is a rapid and easy-to-perform in vitro antifungal susceptibility test. Objective The purpose of this study was to determine the minimal inhibitory concentrations (MICs) of antifungal agents by using the Etest for Candida species isolated from patients with oral...

  17. A Comparison of Antimicrobial Susceptibility and MIC-distributions in Enterococcus Isolates Originating from Humans, Animals and Retail Meat

    Science.gov (United States)

    Objectives: The National Antimicrobial Resistance Monitoring System (NARMS) is a collaborative effort between the Food and Drug Administration's Center for Veterinary Medicine (FDA CVM), U.S. Department of Agriculture (USDA), and the Centers for Disease Control and Prevention (CDC). The NARMS prog...

  18. Increasing Spectrum in Antimicrobial Resistance of Shigella Isolates in Bangladesh: Resistance to Azithromycin and Ceftriaxone and Decreased Susceptibility to Ciprofloxacin

    OpenAIRE

    Mahbubur, Rahman; Shoma, Shereen; Rashid, Harunur; Arifeen, Shams El; Baqui, A. H.; Siddique, A.K.; Nair, G. B.; Sack, D A

    2007-01-01

    Antimicrobial resistance of Shigella isolates in Bangladesh, during 2001-2002, was studied and compared with that of 1991-1992 to identify the changes in resistance patterns and trends. A significant increase in resistance to trimethoprim-sulphamethoxazole (from 52% to 72%, p

  19. [Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1998). III. Secular changes in susceptibility].

    Science.gov (United States)

    Kumamoto, Y; Tsukamoto, T; Hirose, T; Matsukawa, M; Kunishima, Y; Matsuda, S; Sato, S; Ogiwara, M; Ishibashi, K; Fujime, M; Fujita, K; Shigeta, S; Watanabe, J; Igari, J; Yoshida, H; Imafuku, Y; Oguri, T; Murai, M; Yamaguchi, K; Matsumoto, T; Kashitani, F; Watanabe, K; Kobayashi, Y; Uchida, H; Ooe, H; Nishikawa, M; Kohno, S; Oka, T; Takano, Y; Miyagawa, Y; Miyazaki, Y; Izumikawa, K; Yamaguchi, T; Mochida, C; Furuhama, T

    2000-05-01

    Susceptibilities to various antimicrobial agents were examined for Enterococcus faecalis, Staphylococcus aureus, Echerichia coli, Klebsiella spp. and Pseudomonas aeruginosa that were isolated from patients with urinary tract infections (UTIs) in 9 hospitals during June 1998 to May 1999, and the results were compared with those obtained during the same period from 1990 to 1997 in uncomplicated UTIs and complicated UTIs. Among E. faecalis strains, those with low susceptibilities to almost drugs have increased in the latest period. All 5 S. aureus strains isolated from uncomplicated UTIs were the most susceptible to gentamicin (GM). Over 50% of S. aureus strains isolated from complicated UTIs were susceptible to GM, and on the contrary the resistant strains have increased with the MIC90 of 256 micrograms/ml or above. Among S. aureus strains isolated from complicated UTIs, those with low susceptibilities to arbekacin (ABK) have increased in the latest period compared to those during period of 1996-1997, and the MIC90s of them have changed into the lower state from 1 microgram/ml in 1996-1997 to 4 micrograms/ml in 1998. S. aureus strains have continued high susceptibilities to vancomycin (VCM). The susceptibilities to minocycline (MINO) of E. coli showed MIC90: 4 micrograms/ml in 1997, but those have returned in the latest period in uncomplicated UTIs. The MIC90s of ofloxacin (OFLX) to E. coli isolated from uncomplicated and complicated UTIs have been lower 2-3 classes in the latest period than those in 1997. Among Klebsiella spp. strains isolated from uncomplicated UTIs, those with low susceptibilities to almost cephems had increased in 1997, but few of them were detected in the latest study. The sensitive strains of P. aeruginosa to almost drugs have increased during the latest period. The MIC50s of cefozopran (CZOP) and OFLX against P. aeruginosa were the best in our history. The sensitive strains of P. aeruginosa to ceftazidime (CAZ) have increased and its

  20. Antifungal Susceptibility Testing of Dermatophytes: Establishing a Medium for Inducing Conidial Growth and Evaluation of Susceptibility of Clinical Isolates

    OpenAIRE

    Jessup, C. J.; Warner, J.; Isham, N.; Hasan, I.; Ghannoum, M. A.

    2000-01-01

    A standardized reference method for dermatophyte in vitro susceptibility testing is lacking. In a previous study, Norris et al. (H. A. Norris, B. E. Elewski, and M. A. Ghannoum, J. Am. Acad. Dermatol. 40(6, part 2):S9–S13) established the optimal medium and other growth variables. However, the earlier study did not address two issues: (i) selection of an optimal medium for conidial formation by dermatophytes and (ii) validation of the method with a large number of dermatophytes. The present s...

  1. Trends in antimicrobial susceptibility among isolates of Campylobacter species in Ireland and the emergence of resistance to ciprofloxacin.

    LENUS (Irish Health Repository)

    Lucey, B

    2012-02-03

    Measurements were made of the susceptibility to six commonly prescribed antibiotics, including erythromycin, tetracycline and ciprofloxacin, of 130 isolates of Campylobacterjejuni and 15 isolates of Campylobacter coli cultured from human and poultry sources during 2000. The results were compared with the results from a collection of strains isolated between 1996 and 1998. The levels of resistance to erythromycin remained low, 2 per cent and 4.4 per cent for the human and poultry isolates, respectively. Resistance to tetracycline had increased to 31 per cent and 24.4 per cent from 13.9 per cent and 18.8 per cent for the human and poultry isolates, respectively. However, the resistance to ciprofloxacin of the strains isolated during 2000 had increased to 30 per cent, whereas between 1996 and 1998 there had been no resistance to this agent among human isolates, and only 3.1 per cent resistance among poultry isolates. The molecular basis for this resistance has been shown to be the result of a single amino acid substitution, Thr-86-Ile, in the gyrA subunit of DNA gyrase in Cjejuni. A subset of 59 isolates was tested by molecular methods and all of the 25 phenotypically resistant isolates possessed this substitution. None of the human isolates had been treated with ciprofloxacin before their laboratory isolation.

  2. Perfil de susceptibilidade a antimicrobianos em amostras de cocos Gram-positivos, catalase negativos, isoladas de mastite subclínica bubalina Profile of antimicrobial susceptibility in strains of Gram positive cocos, negative catalase, isolated from buffalo subclinical mastitis

    Directory of Open Access Journals (Sweden)

    Maria C.E. Vianni

    2003-06-01

    Full Text Available Estudou-se o perfil de susceptibilidade a antimicrobianos em cocos Gram-positivos catalase negativos (21 amostras de Lactococcus garvieae e 6 de Enterococcus gallinarum, isoladas do leite de fêmeas com mastite subclínica e pertencentes a uma população composta por seis rebanhos bubalinos localizados no Estado do Rio de Janeiro. O teste utilizado foi o da difusão de discos em agar Müller Hinton, segundo recomendações do National Committee for Clinical Laboratory Standards - NCCLS, tendo sido testados discos com ampicilina (10mg, cefalotina (30mg, cefotaxima (30mg, cefoxitina (30mg, cloranfenicol (30mg, eritromicina (15mg, gentamicina (10mg, nitrofurantoína (300mg, norfloxacina (10mg, penicilina (10 UI, tetraciclina (30mg e vancomicina (30mg. Os resultados evidenciaram que em se tratando de Lactococcus garvieae, o antimicrobiano mais eficiente foi o nitrofurantoína com 85,71% de sensibilidade, seguido da cefotaxima (61,90%, vancomicina (52,38%, norfloxacina (47,62% e cefalotina (47,62%. A maior resistência foi desenvolvida frente a penicilina e ampicilina, com 95,24% de resistênciapara os dois antimicrobianos testados. O perfil de susceptibilidade desenvolvido pelas amostras de Enterococcus gallinarum, mostrou baixa sensibilidade frente aos antimicrobianos testados, onde os maiores índices foram observados frente eritromicina e gentamicina, com 33,34% de sensibilidade para ambos; quanto à resistência desenvolvida, foi possível observar 100% de resistência com relação a vancomicina e tetraciclina, seguindo-se cloranfenicol, penicilina, ampicilina, cefoxitina, cefalotina, cefotaxima, norfloxacina e nitrofurantoína, todas evidenciando uma resistência de 83,33% das amostras testadas.The susceptibility of antimicrobials was studied in Gram positive and catalase negative cocci (21 samples of Lactococcus garvieae and 6 Enterococcus gallinarum, isolated from the milk of cows with subclinical mastitis, belonging to six buffalo herds in

  3. Antimicrobial resistance in invasive non-typhoid Salmonella from the Democratic Republic of the Congo: emergence of decreased fluoroquinolone susceptibility and extended-spectrum beta lactamases.

    Directory of Open Access Journals (Sweden)

    Octavie Lunguya

    Full Text Available BACKGROUND: Co-resistance against the first-line antibiotics ampicillin, chloramphenicol and trimethoprim/sulphamethoxazole or multidrug resistance (MDR is common in non typhoid Salmonella (NTS. Use of alternative antibiotics, such as fluoroquinolones or third generation cephalosporins is threatened by increasing resistance, but remains poorly documented in Central-Africa. METHODOLOGY/PRINCIPAL FINDINGS: As part of a microbiological surveillance study in DR Congo, blood cultures were collected between 2007 and 2011. Isolated NTS were assessed for serotype and antimicrobial resistance including decreased ciprofloxacin susceptibility and extended-spectrum beta-lactamase (ESBL production. In total, 233 NTS isolates (representing 23.6% of clinically significant organisms were collected, mainly consisting of Salmonella Typhimurium (79% and Salmonella Enteritidis (18%. The majority of NTS were isolated in the rainy season, and recovered from children ≤2 years old. MDR, decreased ciprofloxacin susceptibility, azithromycin and cefotaxime resistance were 80.7%, 4.3%, 3.0% and 2.1% respectively. ESBL production was noted in three (1.3% isolates. Decreased ciprofloxacin susceptibility was associated with mutations in codon 87 of the gyrA gene, while ESBLs all belonged to the SHV-2a type. CONCLUSIONS/SIGNIFICANCE: Presence of almost full MDR among NTS isolates from blood cultures in Central Africa was confirmed. Resistance to fluoroquinolones, azithromycin and third generation cephalosporins is still low, but emerging. Increased microbiological surveillance in DR Congo is crucial for adapted antibiotic therapy and the development of treatment guidelines.

  4. Multilocus Variable-Number Tandem-Repeat Analysis, Pulsed-Field Gel Electrophoresis, and Antimicrobial Susceptibility Patterns in Discrimination of Sporadic and Outbreak-Related Strains of Yersinia enterocolitica

    Directory of Open Access Journals (Sweden)

    Skurnik Mikael

    2011-02-01

    Full Text Available Abstract Background We assessed the potential of multilocus variable-number tandem-repeat analysis (MLVA, pulsed-field gel electrophoresis (PFGE, and antimicrobial susceptibility testing for discriminating 104 sporadic and outbreak-related Yersinia enterocolitica (YE bio/serotype 3-4/O:3 and 2/O:9 isolates. MLVA using six VNTR markers was performed in two separate multiplex PCRs, and the fluorescently labeled PCR products were accurately sized on an automated DNA sequencer. Results MLVA discriminated 82 sporadic YE 3-4/O:3 and 2/O:9 strains into 77 types, whereas PFGE with the restriction enzyme NotI discriminated the strains into 23 different PFGE pulsotypes. The discriminatory index for a sporadic strain was 0.862 for PFGE and 0.999 for MLVA. MLVA confirmed that a foodborne outbreak in the city of Kotka, Finland in 2003 had been caused by a multiresistant YE 4/O:3 strain that was distinctly different from those of epidemiologically unrelated strains with an identical PFGE pulsotype. The multiresistance of Y. enterocolitica strains (19% of the sporadic strains correlated significantly (p = 0.002 with travel abroad. All of the multiresistant Y. enterocolitica strains belonged to four PFGE pulsotypes that did not contain any susceptible strains. Resistance to nalidixic acid was related to changes in codons 83 or 87 that stemmed from mutations in the gyrA gene. The conjugation experiments demonstrated that resistance to CHL, STR, and SUL was carried by a conjugative plasmid. Conclusions MLVA using six loci had better discriminatory power than PFGE with the NotI enzyme. MLVA was also a less labor-intensive method than PFGE and the results were easier to analyze. The conjugation experiments demonstrated that a resistance plasmid can easily be transferred between Y. enterocolitica strains. Antimicrobial multiresistance of Y. enterocolitica strains was significantly associated with travel abroad.

  5. A new method for normalized interpretation of antimicrobial resistance from disk test results for comparative purposes.

    OpenAIRE

    Kronvall, G; Kahlmeter, G.; Myhre, Erling; Galas, M. F.

    2003-01-01

    Objective To evaluate a calibration method for disk diffusion antibiotic susceptibility tests, using zone diameter values generated in the individual laboratory as the internal calibrator for combinations of antibiotic and bacterial species. Methods The high-zone side of zone histogram distributions was first analyzed by moving averages to determine the peak position of the susceptible population. The accumulated percentages of isolates for the high zone diameter values were calculat...

  6. Incidence, Antimicrobial Susceptibility, and Toxin Genes Possession Screening of Staphylococcus aureus in Retail Chicken Livers and Gizzards

    Directory of Open Access Journals (Sweden)

    Lubna S. Abdalrahman

    2015-04-01

    Full Text Available Few recent outbreaks in Europe and the US involving Campylobacter and Salmonella were linked to the consumption of chicken livers. Studies investigating Staphylococcus aureus in chicken livers and gizzards are very limited. The objectives of this study were to determine the prevalence, antimicrobial resistance, and virulence of S. aureus and MRSA (Methicillin-Resistant Staphylococcus aureus in retail chicken livers and gizzards in Tulsa, Oklahoma. In this study, 156 chicken livers and 39 chicken gizzards samples of two brands were collected. While one of the brands showed very low prevalence of 1% (1/100 for S. aureus in chicken livers and gizzards, the second brand showed prevalence of 37% (31/95. No MRSA was detected since none harbored the mecA or mecC gene. Eighty seven S. aureus isolates from livers and 28 from gizzards were screened for antimicrobial resistance to 16 antimicrobials and the possession of 18 toxin genes. Resistance to most of the antimicrobials screened including cefoxitin and oxacillin was higher in the chicken gizzards isolates. While the prevalence of enterotoxin genes seg and sei was higher in the gizzards isolates, the prevalence of hemolysin genes hla, hlb, and hld was higher in the livers ones. The lucocidin genes lukE-lukD was equally prevalent in chicken livers and gizzards isolates. Using spa typing, a subset of the recovered isolates showed that they are not known to be livestock associated and, hence, may be of a human origin. In conclusion, this study stresses the importance of thorough cooking of chicken livers and gizzards since it might contain multidrug resistant enterotoxigenic S. aureus. To our knowledge this is the first study to specifically investigate the prevalence of S. aureus in chicken livers and gizzards in the US.

  7. Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria

    OpenAIRE

    Olayemi O Ayepola; Olasupo, Nurudeen A.; Egwari, Louis O; Becker, Karsten; Schaumburg, Frieder

    2015-01-01

    Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun Stat...

  8. Development and antimicrobial susceptibility studies of in vitro monomicrobial and polymicrobial biofilm models with Aspergillus fumigatus and Pseudomonas aeruginosa

    OpenAIRE

    Manavathu, Elias K.; Vager, Dora L; Vazquez, Jose A

    2014-01-01

    Background Mixed microbial infections of the respiratory tracts with P. aeruginosa and A. fumigatus capable of producing biofilms are commonly found in cystic fibrosis patients. The primary objective of this study was to develop an in vitro model for P. aeruginosa and A. fumigatus polymicrobial biofilm to study the efficacy of various antimicrobial drugs alone and in combinations against biofilm-embedded cells. Simultaneous static cocultures of P. aeruginosa and sporelings were used for the d...

  9. Perceived susceptibility and self-protective behavior: a field experiment to encourage home radon testing

    International Nuclear Information System (INIS)

    Tested in a field experiment (N = 647) the hypothesis that perceptions of personal susceptibility are important in decisions to test one's home for radioactive radon gas. Experimental group subjects received a personal telephone call to tell them they lived in a high-risk area and a personal letter to reinforce the telephone message. After the intervention, experimental subjects were significantly more likely than minimal-treatment subjects to acknowledge the possibility of high radon levels in their homes. Perceptions of susceptibility and illness severity were significantly correlated with orders of radon test kits and with testing intentions. Nevertheless, there were no differences between groups in test orders or intentions. Results are discussed in terms of the difficulty of getting people to acknowledge susceptibility and the factors other than risk perceptions that influence self-protective behavior

  10. Pulsed-field gel electrophoresis, virulence determinants and antimicrobial susceptibility profiles of type Ia group B streptococci isolated from humans in Brazil

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    Ana Beatriz de A Corrêa

    2009-07-01

    Full Text Available Group B streptococci (GBS infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.

  11. Accelerated electrochemical test of 14Kh17N2 steel susceptibility to ICC

    International Nuclear Information System (INIS)

    Description of the accelerated electrochemical technique used to determine susceptibility 14Kh17N2 steel of ferrite-martensite type to intercrystallite corrosion under the drop of electrolyte, is given. Convergence of the results obtained due to accelerated techniques with those of tests using the All-Union Standards 6032-84 constitutes 95%. These results demonstrate possibility to use data of the accelerated techniques for rapid estimation of susceptibility to ICC of martensite-ferrite steel-14Kh17N2

  12. Multicenter Evaluation of a Nonweekend Reading Schedule for Radiometric Pyrazinamide Susceptibility Testing of Mycobacterium tuberculosis

    OpenAIRE

    Madison, B.; Gross, W.; George, I.; Sloutsky, A.; Washabaugh, G.; Robinson-Dunn, B.; Lipman, H; Metchock, B; Mazurek, G; Ridderhof, J.

    2002-01-01

    Pyrazinamide (PZA) is an integral component of the short-course chemotherapy regimen for tuberculosis. The BACTEC 460TB PZA susceptibility test for Mycobacterium tuberculosis with a daily (D) reading schedule has been available for more than 10 years, but weekend laboratory staffing is necessary. A nonweekend (NW) reading schedule has not been validated in a multicenter study. This prospective multicenter study compares the interlaboratory reproducibility of PZA susceptibility results by foll...

  13. A Counselling Model for BRCA1/2 Genetic Susceptibility Testing

    Directory of Open Access Journals (Sweden)

    van Oostrom Iris

    2004-02-01

    Full Text Available Abstract When BRCA1/2 genetic susceptibility testing was introduced in the clinic in the mid-nineties, the "Huntington protocol" was used in the counselling of individuals applying for genetic testing. This protocol includes at least three sessions with a certain reflection period before blood sampling. Evidence on the psychological impact of BRCA1/2 genetic susceptibility testing has been accumulating in the last years. We will give a short overview of these psychological studies in order to reflect the need of using the extensive Huntington protocol in the counselling of individuals applying for BRCA1/2 genetic susceptibility testing. A shortened and more flexible BRCA1/2 counselling protocol is delineated, in which the attention is focused on the needs and strengths of the individual.

  14. Sequence variant classification and reporting: recommendations for improving the interpretation of cancer susceptibility genetic test results.

    NARCIS (Netherlands)

    Plon, S.E.; Eccles, D.M.; Easton, D.; Foulkes, W.D.; Genuardi, M.; Greenblatt, M.S.; Hogervorst, F.B.; Hoogerbrugge, N.; Spurdle, A.B.; Tavtigian, S.V.

    2008-01-01

    Genetic testing of cancer susceptibility genes is now widely applied in clinical practice to predict risk of developing cancer. In general, sequence-based testing of germline DNA is used to determine whether an individual carries a change that is clearly likely to disrupt normal gene function. Genet

  15. Increased Bacterial Load and Expression of Antimicrobial Peptides in Skin of Barrier-Deficient Mice with Reduced Cancer Susceptibility.

    Science.gov (United States)

    Natsuga, Ken; Cipolat, Sara; Watt, Fiona M

    2016-01-01

    Mice lacking three epidermal barrier proteins-envoplakin, periplakin, and involucrin (EPI-/- mice)-have a defective cornified layer, reduced epidermal γδ T cells, and increased dermal CD4(+) T cells. They are also resistant to developing skin tumors. The tumor-protective mechanism involves signaling between Rae-1 expressing keratinocytes and the natural killer group 2D receptor on immune cells, which also plays a role in host defenses against infection. Given the emerging link between bacteria and cancer, we investigated whether EPI-/- mice have an altered skin microbiota. The bacterial phyla were similar in wild-type and EPI-/- skin. However, bacteria were threefold more abundant in EPI-/- skin and penetrated deeper into the epidermis. The major epithelial defense mechanism against bacteria is production of antimicrobial proteins (AMPs). EPI-/- skin exhibited enhanced expression of antimicrobial peptides. However, reducing the bacterial load by antibiotic treatment or breeding mice under specific pathogen-free conditions did not reduce AMP expression or alleviate the abnormalities in T-cell populations. We conclude that the atopic characteristics of EPI-/- skin are a consequence of the defective barrier rather than a response to the increased bacterial load. It is therefore unlikely that the increase in skin microbiota contributes directly to the observed cancer resistance. PMID:26763429

  16. Rapid antibiotic susceptibility testing of Mycobacterium tuberculosis : Its utility in resource poor settings

    Directory of Open Access Journals (Sweden)

    Poojary A

    2006-01-01

    Full Text Available Purpose: To compare the rapid colorimetric nitrate reductase based antibiotic susceptibility (CONRAS test performed on Mycobacterium tuberculosis isolates with the conventional method i.e., the proportion method. Methods: One hundred clinical isolates of M. tuberculosis were tested for susceptibility to isoniazid (INH and rifampicin (RIF by the conventional proportion method and CONRAS in Middlebrook 7H9 liquid medium enriched with growth supplements (MB7H9S. Results: The performance of the CONRAS test was evaluated using proportion method as the gold standard. The sensitivity (ability to detect true drug resistance and specificity (ability to detect true drug susceptibility of the CONRAS test to INH was 93.75 and 98.52% and for RIF it was 96.10 and 100% respectively. The mean time for reporting was 6.3 days and the test showed excellent reproducibility. The kappa (k value for INH was 0.92 and for RIF was 0.99, indicating excellent agreement between the two methods. Conclusions: CONRAS test is a rapid and reliable method of drug susceptibility for M. tuberculosis.

  17. Antibiotic Susceptibility Testing of the Gram-Negative Bacteria Based on Flow Cytometry.

    Science.gov (United States)

    Saint-Ruf, Claude; Crussard, Steve; Franceschi, Christine; Orenga, Sylvain; Ouattara, Jasmine; Ramjeet, Mahendrasingh; Surre, Jérémy; Matic, Ivan

    2016-01-01

    Rapidly treating infections with adequate antibiotics is of major importance. This requires a fast and accurate determination of the antibiotic susceptibility of bacterial pathogens. The most frequently used methods are slow because they are based on the measurement of growth inhibition. Faster methods, such as PCR-based detection of determinants of antibiotic resistance, do not always provide relevant information on susceptibility, particularly that which is not genetically based. Consequently, new methods, such as the detection of changes in bacterial physiology caused by antibiotics using flow cytometry and fluorescent viability markers, are being explored. In this study, we assessed whether Alexa Fluor® 633 Hydrazide (AFH), which targets carbonyl groups, can be used for antibiotic susceptibility testing. Carbonylation of cellular macromolecules, which increases in antibiotic-treated cells, is a particularly appropriate to assess for this purpose because it is irreversible. We tested the susceptibility of clinical isolates of Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, to antibiotics from the three classes: β-lactams, aminoglycosides, and fluoroquinolones. In addition to AFH, we used TO-PRO®-3, which enters cells with damaged membranes and binds to DNA, and DiBAC4 (3), which enters cells with depolarized membranes. We also monitored antibiotic-induced morphological alterations of bacterial cells by analyzing light scattering signals. Although all tested dyes and light scattering signals allowed for the detection of antibiotic-sensitive cells, AFH proved to be the most suitable for the fast and reliable detection of antibiotic susceptibility. PMID:27507962

  18. Comparison of Disk Diffusion and Agar Dilution Methods for Erythromycin and Ciprofloxacin Susceptibility Testing of Campylobacter jejuni subsp. jejuni▿

    OpenAIRE

    Gaudreau, Christiane; Girouard, Yves; Ringuette, Louise; Tsimiklis, Catherine

    2007-01-01

    Disk diffusion was a reliable, easy, and inexpensive method for testing the susceptibility of Campylobacter jejuni to erythromycin (215 susceptible and 45 resistant isolates) and to ciprofloxacin (154 susceptible, two intermediate, and 124 resistant isolates) using, respectively, an erythromycin disk and ciprofloxacin and nalidixic acid disks.

  19. Comparison of E. Test and Disk Diffusion Agar in Antibiotic Susceptibility of E. coli Isolated from Patients with Urinary Tract Infection in Shariati Hospital (Iran

    Directory of Open Access Journals (Sweden)

    2008-01-01

    Full Text Available Urinary Tract Infection (UTI is one of the most common bacterial infections and E.coli is known to be as an important cause of UTIs. Because bacterial resistances to antibiotics are increasing, therefore a reliable method of antimicrobial resistance detection is important in treatment of UTIs. The objective of the present study is to evaluate and compare the performance of disk diffusion agar with E.test for antimicrobial susceptibility testing of E.coli isolated from UTI. This study was carried out on 250 isolates of E.coli from patients with UTI in Shariati Hospital of Tehran University of Medical Sciences in year 2005. Antibiotic susceptibility testing was performed by disk diffusion method (Iranian and Italian for Trimetoprim sulfhamethoxazole, Gentamysin, Ceftazidim, Nitrofurantoin and Ciprofluxacin and Minimum Inhibitory Concentration (MIC determination was performed by E.test for the same set of antimicrobial. All tests were performed on Muller Hinton agar. The results of this study show that disk diffusion agar may be used as a preliminary screen for antibiotic susceptibility testing of E.coli and is less sensitive than Italian disk diffusion and E.test. By comparison of 3 above mentioned methods E.test is the most sensitive and shows the effective dose of antibiotic for treatment and prevention of antibiotic resistance. Comparison of E.test with Iranian disk diffusion agar showed paramount differences in antibiotic agreement (max 37.8 % these differences in case of Ceftazidim and Gentamysin were, respectively 76.8 and 62.2% whereas comparison of E.test with Italian disk diffusion agar showed less difference of antibiotics agreement (max 11.2%.

  20. Antimicrobial Drug Resistance of Salmonella enterica Serovar Typhi in Asia and Molecular Mechanism of Reduced Susceptibility to the Fluoroquinolones▿

    OpenAIRE

    Chau, Tran Thuy; Campbell, James Ian; Galindo, Claudia M; Van Minh Hoang, Nguyen; Diep, To Song; Nga, Tran Thu Thi; Van Vinh Chau, Nguyen; Tuan, Phung Quoc; Page, Anne Laure; Ochiai, R. Leon; Schultsz, Constance; Wain, John; Bhutta, Zulfiqar A; Parry, Christopher M.; Bhattacharya, Sujit K.

    2007-01-01

    This study describes the pattern and extent of drug resistance in 1,774 strains of Salmonella enterica serovar Typhi isolated across Asia between 1993 and 2005 and characterizes the molecular mechanisms underlying the reduced susceptibilities to fluoroquinolones of these strains. For 1,393 serovar Typhi strains collected in southern Vietnam, the proportion of multidrug resistance has remained high since 1993 (50% in 2004) and there was a dramatic increase in nalidixic acid resistance between ...

  1. In vitro antimicrobial susceptibility of single and mixed populations in cystic fibrosis: the role of novel microorganisms

    OpenAIRE

    Lopes, Susana Patrícia; Ceri, H.; Azevedo, N. F.; Pereira, Maria Olívia

    2011-01-01

    Pseudomonas aeruginosa is the dominant pathogen associated with bacterial infections occurring in Cystic Fibrosis (CF) patients, resulting in 80% of mortality in adults. However, pulmonary infection has recently been defined as polymicrobial, involving classical and other unusual bacteria, which may play a crucial role when associated with the conventional ones. This work aims to evaluate the susceptibility patterns of mono and dual-species biofilms encompassing traditional and emerging micro...

  2. Prevotella intermedia and Porphyromonas gingivalis isolated from osseointegrated dental implants: colonization and antimicrobial susceptibility Prevotella intermedia e Porphyromonas gingivalis isolados de implantes osseointegrados: colonização e susceptibilidade a antimicrobianos

    Directory of Open Access Journals (Sweden)

    Eduardo Augusto Pfau

    2005-09-01

    Full Text Available The colonization and antimicrobial susceptibility of P. intermedia and P. gingivalis isolated from peri-implant and gingival sulcus samples were determined. Samples were collected from 30 patients submitted to implant in three different times: at the moment of the surgery, 20 and 60 days after the implant installation. Organisms were identified by using a biochemical tests or API 32-A kit and by PCR. The antimicrobial susceptibility was determined by using an agar dilution method. Nineteen P. intermedia (4 from peri-implant sites and 15 from gingival sulcus, and only seven P. gingivalis from gingival sulcus were isolated. Organisms were detected by PCR from seven peri-implant and 32 gingival samples. Bacteria were susceptible to the used antibiotics except to azithromycin with 65% of resistance for P. intermedia strains. Both tested species were susceptible to cadmium, nickel and palladium, and showed different resistance rates to titanium, aluminum and mercuric chloride. Most of P. intermedia strains were resistant to lead, silver, copper, titanium, zinc, aluminum and mercuric chloride. Bacteria colonized implants after 60 days of surgery and PCR may be used as a tool for bacterial detection in implantology.Neste estudo foram avaliadas a colonização e a susceptibilidade a antimicrobianos de P. intermedia e P. gingivalis isolados de amostras de sulcus gengivais e peri-implantares. As amostras foram coletadas de 30 pacientes submetidos a implantes, em três tempos diferentes: no momento da cirurgia, 20 e 60 dias após a instalação do implante. Os organismos foram identificados por testes bioquímicos ou por kit comercial API 32-A e por PCR. A susceptibilidade antimicrobiana foi determinada usando-se o método de diluição em ágar. Foram isolados dezenove P. intermedia (quatro de peri-implantites e 15 de sulco gengival e somente sete P. gingivalis de sulco gengival. Pelo PCR os organismos foram detectados de sete amostras sete peri

  3. Change of antibiotic susceptibility testing guidelines from CLSI to EUCAST: influence on cumulative hospital antibiograms.

    Directory of Open Access Journals (Sweden)

    Aline Wolfensberger

    Full Text Available OBJECTIVE: We studied whether the change in antibiotic susceptibility testing (AST guidelines from CLSI to EUCAST influenced cumulative antibiograms in a tertiary care hospital in Switzerland. METHODS: Antibiotic susceptibilities of non-duplicate isolates collected within a one-year period before (period A and after (period B changing AST interpretation from CLSI 2009 to EUCAST 1.3 (2011 guidelines were analysed. In addition, period B isolates were reinterpreted according to the CLSI 2009, CLSI 2013 and EUCAST 3.1 (2013 guidelines. RESULTS: The majority of species/drug combinations showed no differences in susceptibility rates comparing periods A and B. However, in some gram-negative bacilli, decreased susceptibility rates were observed when comparing CLSI 2009 with EUCAST 1.3 within period B: Escherichia coli / cefepime, 95.8% (CLSI 2009 vs. 93.1% (EUCAST 1.3, P=0.005; Enterobacter cloacae / cefepime, 97.0 (CLSI 2009 vs. 90.5% (EUCAST 1.3, P=0.012; Pseudomonas aeruginosa / meropenem, 88.1% (CLSI 2009 vs. 78.3% (EUCAST 1.3, P=0.002. These differences were still evident when comparing susceptibility rates according to the CLSI 2013 guideline with EUCAST 3.1 guideline. For P. aeruginosa and imipenem, a trend towards a lower antibiotic susceptibility rate in ICUs compared to general wards turned into a significant difference after the change to EUCAST: 87.9% vs. 79.8%, P=0.08 (CLSI 2009 and 86.3% vs. 76.8%, P=0.048 (EUCAST 1.3. CONCLUSIONS: The change of AST guidelines from CLSI to EUCAST led to a clinically relevant decrease of susceptibility rates in cumulative antibiograms for defined species/drug combinations, particularly in those with considerable differences in clinical susceptibility breakpoints between the two guidelines.

  4. Growth inhibition of Mycobacterium tuberculosis by polyoxyethylene stearate present in the BACTEC pyrazinamide susceptibility test.

    OpenAIRE

    Miller, M A; Thibert, L; Desjardins, F; Siddiqi, S H; Dascal, A

    1996-01-01

    We have previously found that approximately 3.5% of 428 clinical isolates of Mycobacterium tuberculosis yield uninterpretable results in the BACTEC pyrazinamide (PZA) susceptibility test system, because of inadequate growth. We tested the hypothesis that polyoxyethylene stearate (POES), the ingredient of the reconstituting fluid for the test, was the cause of this growth inhibition. A total of 15 isolates known for their previously uninterpretable results and 100 randomly chosen clinical isol...

  5. Modified broth-disk method for testing the antibiotic susceptibility of anaerobic bacteria.

    Science.gov (United States)

    Wilkins, T D; Thiel, T

    1973-03-01

    The most commonly used method for testing the antibiotic susceptibility of aerobic and facultative bacteria is the disk diffusion method. However, some anaerobic bacteria do not grow well enough in anaerobic jars for performance of disk diffusion tests. A modification of the broth-disk method of Schneierson allowed us to determine antibiotic susceptibility in a completely anaerobic environment. Commercial antibiotic disks were added anaerobically to tubes of prereduced brain heart infusion broth to achieve a concentration of each antibiotic approximating that attainable in blood. The tubes were then inoculated and incubated for 18 h. Resistance or susceptibility to each antibiotic was determined according to the amount of growth in each tube as compared with a control culture without the antibiotic. There was good correlation between results obtained by this broth-disk method and minimal inhibitory concentrations. PMID:4790595

  6. Antimicrobial activity of the crude ethanol extract and fractions from Eugenia uniflora leaves against Pseudomonas aeruginosa

    OpenAIRE

    Tatiana S. Fiuza; Sabóia Morais, Simone M.T.; José R. Paula; Leonice M.F. Tresvenzol; Carmo Filho, José R.; Fabiana C Pimenta

    2009-01-01

    This study evaluated the antimicrobial activity of the crude ethanol extract and fractions from Eugenia uniflora L. leaves against Pseudomonas aeruginosa. A total of 72 P. aeruginosa isolated from patients of three hospitals in Goiânia and 8 standard strains were selected to test antimicrobial activity. The bacteria susceptibility profile against 15 antimicrobial agents was determined using the disc diffusion method. The minimum inhibitory concentration of the crude ethanol extract and the et...

  7. Negative temperament as a moderator of intervention effects in infancy: testing a differential susceptibility model.

    Science.gov (United States)

    Anzman-Frasca, Stephanie; Stifter, Cynthia A; Paul, Ian M; Birch, Leann L

    2014-10-01

    A consideration of potential moderators can highlight intervention effects that are attenuated when investigating aggregate results. Differential susceptibility is one type of interaction, where susceptible individuals have poorer outcomes in negative environments and better outcomes in positive environments, compared to less susceptible individuals, who have moderate outcomes regardless of environment. In the current study, we provide rationale for investigating this type of interaction in the context of a behavioral childhood obesity preventive intervention and test whether infant negativity moderated intervention effects on infant self-regulation and weight gain and on two aspects of mothers' parenting competence: parenting self-efficacy and parenting satisfaction. Results showed that infants' negative temperament at 3 weeks moderated intervention effects on some, but not all, outcomes. The intervention led to greater parenting satisfaction in mothers with highly negative infants but did not affect parenting satisfaction in mothers with less negative infants, consistent with a model of differential susceptibility. There was also a trend toward less weight gain in highly negative intervention group infants. In contrast, there was a main effect of the intervention on infant self-regulation at 1 year, such that the intervention group had higher observed self-regulation, across levels of infant negativity. Results support the importance of incorporating tests of moderation into evaluations of obesity interventions and also illustrate that individuals may be differentially susceptible to environmental effects on some outcomes but not others. PMID:23832637

  8. Evaluation of rapid radiometric method for drug susceptibility testing of Mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    A total of 106 isolates of Mycobacterium tuberculosis were tested for drug susceptibility by the conventional 7H11 plate method and by a new rapid radiometric method using special 7H12 liquid medium with 14C-labeled substrate. Results obtained by the two methods were compared for rapidity, sensitivity, and specificity of the new test method. There was 98% overall agreement between the results obtained by the two methods. Of a total of 424 drug tests, only 8 drug results did not agree, mostly in the case of streptomycin. This new procedure was found to be rapid, with 87% of the tests results reportable within 4 days and 98% reportable within 5 days as compared to the usual 3 weeks required with the conventional indirect susceptibility test method. The results of this preliminary study indicate that the rapid radiometric method seems to have the potential for routine laboratory use and merits further investigations

  9. Comparison of manual mycobacteria growth indicator tube and epsilometer test with agar proportion method for susceptibility testing of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    N Karabulut

    2014-01-01

    Full Text Available Background and Objectives: Antimycobacterial susceptibility tests take weeks, and delayed therapy can lead to spread of Mycobacterium tuberculosis. Therefore, rapid, accurate and cost-effective methods are required for proper therapy selection. In this study, the Mycobacteria growth indicator tube (MGIT and epsilometer test (Etest methods were compared to the agar proportion method for susceptibility testing of Mycobacterium tuberculosis. Materials and Methods: The susceptibility tests against isoniazid (INH, rifampin (RIF, streptomycin (STM and ethambutol (ETM of 51 M. tuberculosis complex isolates were analyzed by the MGIT, Etest and agar proportion methods. Results: The concordance between MGIT/Etest and agar proportion methods was 98% for INH and 100% for RIF, STM, ETM. There were not statistically significant differences in results of the susceptibility tests between MGIT/Etest and the reference agar proportion method. Conclusion: The results have shown that MGIT and Etest methods can be used instead of the agar proportion method, because these two methods are more rapid and easier than the agar proportion method.

  10. Recovery rates, serotypes, and antimicrobial susceptibility patterns of Salmonellae isolated from cloacal swabs of wild Nile crocodiles (Crocodylus niloticus) in Zimbabwe

    DEFF Research Database (Denmark)

    Madsen, Mogens; Hangartner, P.; West, K.; Kelly, P.

    1998-01-01

    Samples from the cloaca and the ventral skin surface of 67 Nile crocodiles (Crocodylus niloticus) captured in four uninhabited areas at Lake Kariba, Zimbabwe, were cultured for Salmonella. All the skin samples tested negative for Salmonella, whereas 18 of 67 (26.9%) cloacal samples grew Salmonella...... subspecies enterica displayed invasive properties in an experimental mouse model and thus exhibited pathogenic potential, whereas none of the other isolates were invasive. In general, isolates were sensitive to a number of commonly used antimicrobials, except for three isolates that were resistant to...

  11. Agar diffusion tests with cefuroxime disks for predicting ceftriaxone susceptibility among isolates of Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Dias Cícero A.G.

    1998-01-01

    Full Text Available The performance of agar diffusion tests using disks of cefuroxime (30µg for predicting ceftriaxone susceptibility in 33 isolates of Streptococcus pneumoniae was studied. All 7 resistant isolates to ceftriaxone (MIC ³1.0 µg/ml exhibited zones of inhibition <28mm. The procedure can be easily adapted to clinical laboratories.

  12. .i.Aspergillus viridinutans./i. complex: polyphasic taxonomy, mating behaviour and antifungal susceptibility testing

    Czech Academy of Sciences Publication Activity Database

    Dudová, Z.; Hubka, V.; Svobodová, L.; Hamal, P.; Nováková, Alena; Matsuzawa, T.; Yaguchi, T.; Kubátová, A.; Kolařík, Miroslav

    2013-01-01

    Roč. 56, Suppl. 3 (2013), s. 162-163. ISSN 0933-7407. [Trends in Medical Mycology /6./. 11.10.2013-14.10.2013, Copenhagen] Institutional support: RVO:60077344 ; RVO:61388971 Keywords : Aspergillus viridinutans * polyphasic taxonomy * mating behaviour * antifungal susceptibility testing Subject RIV: EE - Microbiology, Virology

  13. Panton-Valentine leukocidin and some exotoxins of Staphylococcus aureus and antimicrobial susceptibility profiles of staphylococci isolated from milks of small ruminants.

    Science.gov (United States)

    Ünal, Nilgün; Askar, Şinasi; Macun, Hasan Ceyhun; Sakarya, Fatma; Altun, Belgin; Yıldırım, Murat

    2012-03-01

    The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats' milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August 2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected. Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4), 3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton-Valentine leukocidin produced by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity. PMID:21800213

  14. Multilaboratory Evaluation of In Vitro Antifungal Susceptibility Testing of Dermatophytes for ME1111.

    Science.gov (United States)

    Ghannoum, M; Chaturvedi, V; Diekema, D; Ostrosky-Zeichner, L; Rennie, R; Walsh, T; Wengenack, N; Fothergill, A; Wiederhold, N

    2016-03-01

    ME1111 is a novel small molecule antifungal agent under development for the topical treatment of onychomycosis. Standardization of the susceptibility testing method for this candidate antifungal is needed. Toward this end, 8 independent laboratories determined the interlaboratory reproducibility of ME1111 susceptibility testing. In addition, we subsequently identified 2 strains as quality control (QC) isolates for the method. In the reproducibility study, 5 blinded clinical strains each of Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum were tested, while the QC study tested 6 blinded T. rubrum or T. mentagrophytes ATCC strains. Testing was performed in frozen microtiter panels according to the Clinical and Laboratory Standards Institute (CLSI) M38-A2 methodology. In the reproducibility study, 9 of 15 clinical strains showed interlaboratory agreement of >90% at the 80% inhibition endpoint, with a range of agreement of 76.2% to 100%. In the QC study, 4 of the 6 ATCC strains showed interlaboratory agreement of >90%. ME1111 demonstrated excellent interlaboratory agreement when tested against dermatophytes. Based on this data, the CLSI Subcommittee on Antifungal Susceptibility Tests approved the susceptibility testing of ME1111 against dermatophytes according to M38-A2 methodology, which stipulates RPMI 1640 as the test medium, an inoculum size of 1 to 3 × 10(3) CFU/ml, and an incubation time and temperature of 96 h at 35°C. The MIC endpoint should be 80% inhibition compared with the growth control. T. rubrum ATCC MYA-4438 and T. mentagrophytes ATCC 28185 were selected as QC isolates, with an acceptable range of 0.12 to 1 μg/ml for the two strains. PMID:26719434

  15. Results of German multicenter study of antimicrobial susceptibilities of Trichophyton rubrum and Trichophyton mentagrophytes strains causing tinea unguium. German Collaborative Dermatophyte Drug Susceptibility Study Group.

    OpenAIRE

    Korting, H C; Ollert, M.; Abeck, D.

    1995-01-01

    Thirty-two strains of Trichophyton rubrum and 16 strains of Trichophyton mentagrophytes isolated from patients with tinea unguium in various parts of Germany were subjected to a microdilution test with six systemic or topical antimycotic agents. Apart from griseofulvin, there were no species-specific differences between the two species. Terbinafine was the most active antimycotic agent, with a MIC not exceeding 0.05 micrograms/ml.

  16. Development of EUCAST disk diffusion method for susceptibility testing of the Bacteroides fragilis group isolates.

    Science.gov (United States)

    Nagy, Elisabeth; Justesen, Ulrik Stenz; Eitel, Zsuzsa; Urbán, Edit

    2015-02-01

    With the emergence of antibiotic resistance among Bacteroides fragilis group isolates the need of susceptibility testing in routine laboratories is increasing. The aims of the present study were to evaluate the disk diffusion method for susceptibility testing in case of different clinical isolates of Bacteroides spp by comparing zone diameter results with MICs obtained earlier during an Europe-wide antibiotic susceptibility surveillance, and to propose zone diameter breakpoints, which correlate for the EUCAST MIC breakpoints. We tested 381 clinical isolates of the B. fragilis group to amoxicillin/clavulanic acid, cefoxitin, clindamycin, imipenem, metronidazole, moxifloxacin, piperacillin/tazobactam, tigecycline by agar dilution method previously. The inhibition zones of the same antibiotics including meropenem disc were determined by the disc diffusion on Brucella blood agar supplemented with haemin and vitamin K1. Plates were incubated at 37 °C in an anaerobic atmosphere for 24 h. The zone diameters were read at 100% inhibition. In case of discrepant results MICs were determined by gradient test and compared with the inhibition zones on the same plate. We found a good agreement between the inhibition zone diameters and the MICs for imipenem, metronidazole, moxifloxacin and tigecyclin. The inhibition zone diameters of meropenem also separated clearly the isolates, which can be considered wild-type isolates. In case of amoxicillin/clavulanic acid and piperacillin/tazobactam intermediate and susceptible isolates according to the MIC determination, overlap during the zone diameter determination. Isolates with an inhibition zone disk diffusion can be an option for susceptibility testing of B. fragilis group isolates for most relevant antibiotics in routine laboratories. PMID:25464140

  17. The Role of Phosphoglycans in the Susceptibility of Leishmania mexicana to the Temporin Family of Anti-Microbial Peptides

    Directory of Open Access Journals (Sweden)

    Gabriela A. Eggimann

    2015-02-01

    Full Text Available Natural product antimicrobial peptides (AMPs have been proposed as promising agents against the Leishmania species, insect vector borne protozoan parasites causing the neglected tropical disease leishmaniasis. However, recent studies have shown that the mammalian pathogenic amastigote form of L. mexicana, a causative agent of cutaneous leishmaniasis, is resistant to the amphibian-derived temporin family of AMPs when compared to the insect stage promastigote form. The mode of resistance is unknown, however the insect and mammalian stages of Leishmania possess radically different cell surface coats, with amastigotes displaying low (or zero quantities of lipophosphoglycan (LPG and proteophosphoglycan (PPG, macromolecules which form thick a glycocalyx in promastigotes. It has been predicted that negatively charged LPG and PPG influence the sensitivity/resistance of promastigote forms to cationic temporins. Using LPG and PPG mutant L. mexicana, and an extended range of temporins, in this study we demonstrated that whilst LPG has little role, PPG is a major factor in promastigote sensitivity to the temporin family of AMPs, possibly due to the conferred anionic charge. Therefore, the lack of PPG seen on the surface of pathogenic amastigote L. mexicana may be implicated in their resistance to these peptides.

  18. Investigation into the potential of sub-lethal photodynamic antimicrobial chemotherapy (PACT) to reduce susceptibility of meticillin-resistant Staphylococcus aureus (MRSA) to antibiotics

    Science.gov (United States)

    Cassidy, C. M.; Donnelly, R. F.; Tunney, M. M.

    2009-06-01

    In PACT, a combination of a sensitising drug and visible light cause the selective destruction of microbial cells via singlet oxygen production. As singlet oxygen is a non-specific oxidizing agent and is only present during illumination, development of resistance to this treatment is thought to be unlikely. However, in response to oxidative stress, bacteria can up-regulate oxidative stress genes and associated antibiotic resistance genes. The up-regulation of these genes and potential transfer of genetic material may result in a resistant bacterial population. This study determined whether treatment of clinically isolated meticillin resistant Staphylococcus aureus (MRSA) strains with sub-lethal doses of methylene blue (MB) and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP)-PACT resulted in reduced susceptibility to antibiotics and previously lethal PACT. Exposure of strains to sub-lethal doses of photosensitizer in combination with light had no effect on susceptibility to previously lethal photosensitization. Furthermore, exposure to sub-lethal concentrations of both photosensitizers caused no significant changes in the minimum inhibitory concentration (MIC) for each strain tested. Any differences in susceptibility were not significant as they did not cross breakpoints between resistant and susceptible for any organism or antibiotic tested. Therefore, PACT remains an attractive alternative option for treatment of MRSA infections.

  19. SUSCEPTIBILITY TEST FOR FUNGI: CLINICAL AND LABORATORIAL CORRELATIONS IN MEDICAL MYCOLOGY

    Directory of Open Access Journals (Sweden)

    Ana ALASTRUEY-IZQUIERDO

    2015-09-01

    Full Text Available SUMMARYDuring recent decades, antifungal susceptibility testing has become standardized and nowadays has the same role of the antibacterial susceptibility testing in microbiology laboratories. American and European standards have been developed, as well as equivalent commercial systems which are more appropriate for clinical laboratories. The detection of resistant strains by means of these systems has allowed the study and understanding of the molecular basis and the mechanisms of resistance of fungal species to antifungal agents. In addition, many studies on the correlation of in vitro results with the outcome of patients have been performed, reaching the conclusion that infections caused by resistant strains have worse outcome than those caused by susceptible fungal isolates. These studies have allowed the development of interpretative breakpoints for Candida spp. and Aspergillus spp., the most frequent agents of fungal infections in the world. In summary, antifungal susceptibility tests have become essential tools to guide the treatment of fungal diseases, to know the local and global disease epidemiology, and to identify resistance to antifungals.

  20. Establishing a Method of Inoculum Preparation for Susceptibility Testing of Trichophyton rubrum and Trichophyton mentagrophytes

    OpenAIRE

    Santos, D. A.; Barros, M. E. S.; J. S. Hamdan

    2006-01-01

    A total of 92 clinical isolates of dermatophytes (52 of Trichophyton rubrum and 40 of Trichophyton mentagrophytes) were selected for testing with six antifungal drugs (terbinafine, griseofulvin, clotrimazole, miconazole, isoconazole, and fluconazole) and two pairs of drug combinations (ketoconazole-cyclopiroxolamine and itraconazole-cyclopiroxolamine). Two methods of inoculum preparation for susceptibility testing were evaluated that used (i) inocula consisting only of microconidia of dermato...