Lisa F Dawson
Full Text Available The increased prevalence of Clostridium difficile infection (CDI has coincided with enhanced transmissibility and severity of disease, which is often linked to two distinct clonal lineages designated PCR-ribotype 027 and 017 responsible for CDI outbreaks in the USA, Europe and Asia. We assessed sporulation and susceptibility of three PCR-ribotypes; 012, 017 and 027 to four classes of disinfectants; chlorine releasing agents (CRAs, peroxygens, quaternary ammonium compounds (QAC and biguanides. The 017 PCR-ribotype, showed the highest sporulation frequency under these test conditions. The oxidizing biocides and CRAs were the most efficacious in decontamination of C. difficile vegetative cells and spores, the efficacy of the CRAs were concentration dependent irrespective of PCR-ribotype. However, there were differences observed in the susceptibility of the PCR-ribotypes, independent of the concentrations tested for Virkon®, Newgenn®, Proceine 40® and Hibiscrub®. Whereas, for Steri7® and Biocleanse® the difference observed between the disinfectants were dependent on both PCR-ribotype and concentration. The oxidizing agent Perasafe® was consistently efficacious across all three PCR ribotypes at varying concentrations; with a consistent five Log10 reduction in spore titre. The PCR-ribotype and concentration dependent differences in the efficacy of the disinfectants in this study indicate that disinfectant choice is a factor for llimiting the survival and transmission of C. difficile spores in healthcare settings.
Romano, Vincenza; Krovacek, Karel; Mauri, Federica; Demarta, Antonella; Dumontet, Stefano
The occurrence of Clostridium difficile in nine wastewater treatment plants in the Ticino Canton (southern Switzerland) was investigated. The samples were collected from raw sewage influents and from treated effluents. Forty-seven out of 55 characterized C. difficile strains belonged to 13 different reference PCR ribotypes (009, 010, 014, 015, 039, 052, 053, 066, 070, 078, 101, 106, and 117), whereas 8 strains did not match any of those available in our libraries. The most frequently isolated ribotype (40%) was 078, isolated from six wastewater treatment plants, whereas ribotype 066, a toxigenic emerging ribotype isolated from patients admitted to hospitals in Europe and Switzerland, was isolated from the outgoing effluent of one plant. The majority of the isolates (85%) were toxigenic. Forty-nine percent of them produced toxin A, toxin B, and the binary toxin (toxigenic profile A+ B+ CDT+), whereas 51% showed the profile A+ B+ CDT−. Interestingly, eight ribotypes (010, 014, 015, 039, 066, 078, 101, and 106) were among the riboprofiles isolated from symptomatic patients admitted to the hospitals of the Ticino Canton in 2010. Despite the limitation of sampling, this study highlights that toxigenic ribotypes of C. difficile involved in human infections may occur in both incoming and outgoing biological wastewater treatment plants. Such a finding raises concern about the possible contamination of water bodies that receive wastewater treatment plant effluents and about the safe reuse of treated wastewater. PMID:22798376
Full Text Available Abstract Background In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested for their efficacy against spores of distinctive C. difficile PCR ribotypes. Methods Four different products were tested; 1 hydrogen peroxide 1.5%; 2 glucoprotamin 1.5%; 3 a mixture of ethanol, propane and N-alkyl amino propyl glycine; and 4 a mixture of didecyldimonium chloride, benzalkonium chloride, polyaminopropyl, biguanide and dimenthicone as active ingredients. Tiles were contaminated with a test solution containing a concentration of 5x106CFU/ml spores of C. difficile strains belonging to PCR ribotypes 010, 014 or 027. The tiles were left to dry for an hour and then wiped or sprayed with one of the sprays or wipes as intended by the manufacturers. When products neutralized after 5 min, microbiological cultures and ATP measures were performed. Results Irrespective of the disinfection method, the microbial count log10 reduction of C. difficile PCR ribotype 010 was highest, followed by the reduction of C. difficile 014 and C. difficile 027. Overall, the wipes performed better than the sprays with the same active ingredient. On average, although not significantly, a difference in relative light units (RLU reduction between the wipes and sprays was found. The wipes had a higher RLU log10 reduction, but no significant difference for RLU reduction was observed between the different C. difficile strains (p = 0.16. Conclusion C. difficile spores of PCR ribotypes 014 and 027 strains are more difficult to eradicate than non-toxigenic PCR ribotype 010. In general, impregnated cleaning/disinfection wipes performed better than ready-to-use sprays. Wipes with hydrogen peroxide (1.5% showed the highest bactericidal activity.
Debast, Sylvia B.; van Leengoed, Leo A. M. G.; Goorhuis, Abraham; Harmanus, Celine; Kuijper, Ed J.; Bergwerff, Aldert A.
In diseased piglets from two Dutch pig-breeding farms with neonatal diarrhoea for more than a year, culture and PCR analyses identified the involved microorganism as Clostridium difficile PCR ribotype 078 harbouring toxin A (tcdA) and B (tcdB), and binary toxin genes. Isolated strains showed a 39 bp
Kuijper, E J
Outbreaks of Clostridium difficile infections (CDI) with increased severity, high relapse rate and significant mortality have been related to the emergence of a new, hypervirulent C. difficile strain in North America and Europe. This emerging strain is referred to as PCR ribotype 027 (Type 027). Since 2005, individual countries have developed surveillance studies about the spread of type 027.C. difficile Type 027 has been reported in 16 European countries. It has been responsible for outbreaks in Belgium, Germany, Finland, France, Ireland, Luxembourg, The Netherlands, Switzerland and the United Kingdom (England, Wales, Northern Ireland and Scotland). It has also been detected in Austria, Denmark, Sweden, Norway, Hungary, Poland and Spain. Three countries experienced imported patients with CDI due to Type 027 who acquired the infection abroad.The antimicrobial resistance pattern is changing, and outbreaks due to clindamycin-resistant ermB positive Type 027 strains have occurred in three European countries. Ongoing epidemiological surveillance of cases of CDI, with periodic characterisation of the strains involved, is required to detect clustering of cases in time and space and to monitor the emergence of new, highly virulent clones.
Zidaric, V.; Janezic, S.; Indra, A.
Clostridium difficile is an anaerobic sporogenic bacterium traditionally associated with human nosocomial infections, and animals have been recognized as an important potential reservoir for human infections (Rodriguez-Palacios et al., 2013). Ribotype 078 is often reported in animals but according...
Analysis of proteomes released from in vitro cultured eight Clostridium difficile PCR ribotypes revealed specific expression in PCR ribotypes 027 and 176 confirming their genetic relatedness and clinical importance at the proteomic level
Dresler, J.; Krůtová, M.; Fučíková, A.; Klimentová, J.; Hrůzová, V.; Ďuráčová, M.; Houdková, K.; Salovská, B.; Matějková, J.; Hubálek, Martin; Pajer, P.; Píša, L.; Nyč, O.
Roč. 9, Aug 14 (2017), č. článku 45. ISSN 1757-4749 Institutional support: RVO:61388963 Keywords : Clostridium difficile * label-free quantification * proteome * PCR ribotype 027 * PCR ribotype 176 Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.756, year: 2016 https://gutpathogens.biomedcentral.com/articles/10.1186/s13099-017-0194-9
Antimicrobial use is recognized as a risk factor for Clostridium difficile infection (CDI) and outbreaks. We studied the relationship between PCR ribotype, antimicrobial susceptibility and the genetic basis of resistance in response to exposure to antimicrobial agents.
Nishimura, Satoshi; Kou, Tadayuki; Kato, Haru; Watanabe, Masaki; Uno, Shoichi; Senoh, Mitsutoshi; Fukuda, Tadashi; Hata, Atsuko; Yazumi, Shujiro
In the past two decades, Clostridium difficile polymerase chain reaction ribotype 027 strain has rapidly emerged as the leading cause of antibiotic-associated colitis in North America and Europe; however, it has been reported only occasionally in Japan. We report a case of fulminant pseudomembranous colitis caused by this strain in a healthy young woman in Japan without any previous medical history. The strain isolated from our patient was susceptible to both gatifloxacin and moxifloxacin, thus representing a historic strain. The acquisition of fluoroquinolone resistance was reported as the important key genetic event linked to the virulence of this strain. It is noteworthy that the fluoroquinolone-susceptible 027 strain caused fulminant colitis in a healthy young woman in a non-endemic area. Our experience suggests that C. difficile PCR ribotype 027 has the potential virulence factors that are not associated with a fluoroquinolone resistance-conferring mutation. Copyright © 2014. Published by Elsevier Ltd.
Kuijper, Ed J.; van den Berg, Renate J.; Debast, Sylvia; Visser, Caroline E.; Veenendaal, Dick; Troelstra, Annet; van der Kooi, Tjallie; van den Hof, Susan; Notermans, Daan W.
Outbreaks due to Clostridium difficile polymerase chain reaction (PCR) ribotype 027, toxinotype III, were detected in 7 hospitals in the Netherlands from April 2005 to February 2006. One hospital experienced at the same time a second outbreak due to a toxin A-negative C. difficile PCR ribotype 017
Kuijper, Ed J; Berg, Renate J van den; Debast, Sylvia; Visser, Caroline E; Veenendaal, Dick; Troelstra, Annet; Kooi, Tjallie van der; Hof, Susan van den; Notermans, Daan W
Outbreaks due to Clostridium difficile polymerase chain reaction (PCR) ribotype 027, toxinotype III, were detected in 7 hospitals in the Netherlands from April 2005 to February 2006. One hospital experienced at the same time a second outbreak due to a toxin A-negative C. difficile PCR ribotype 017
A repetitive-extragenic palindromic PCR (rep-PCR) subtyping method (DiversiLab) in conjunction with ribotyping, toxinotyping and antimicrobial-susceptibility testing was used to detect subtypes within Clostridium difficile ribotypes 027 and 078. Clinical isolates of ribotypes 027 (toxinotype III) (n = 30) and 078 (toxinotype V) (n = 23) were provided by health-care facilities across the Republic of Ireland over 2 months in 2006 and 1 month in 2009. Ribotype 027 isolates were significantly more related to each other (9 different subtype profiles) when compared to ribotype 078 isolates (14 different profiles) (P = 0.001; cut-off >90 % similarity). Almost half of ribotype 078 isolates (45.5 %) showed no relationship to each other. The clonality of ribotype 027 isolates suggests effective adaptation to the human niche, whereas the considerable genetic diversity within ribotype 078 isolates suggests that they may have originated from a variety of sources. Subtyping correlated well with antimicrobial susceptibility, in particular clindamycin susceptibility for ribotype 027, but diverse antimicrobial-susceptibility profiles were seen in ribotype 078 isolates, even within a single health-care facility. Between 2006 and 2009, a change in the predominant subtype of ribotype 027 was seen, with the recent clone representing half of all ribotype 027 isolates studied. This strain exhibited 89 % similarity to a rep-PCR profile of the North American NAP-1 strain.
T.I.I. van der Kooi; M. Koningstein; A. Lindemans (Anouk); D.W. Notermans (Daan); E. Kuijper; R.J. van den Berg (Renate); H.C. Boshuizen (Hendriek); P.M.G. Filius (Margreet); S. van den Hof
textabstractThe first Dutch outbreak due to Clostridium difficile ribotype 027 was observed in mid-2005; by the end of that year, eight hospitals were affected. To study the relationship between hospital-wide antibiotic use and the incidence of 027-linked C. difficile-associated disease (CDAD) three
Warren N Fawley
Full Text Available PCR-ribotyping has been adopted in many laboratories as the method of choice for C. difficile typing and surveillance. However, issues with the conventional agarose gel-based technique, including inter-laboratory variation and interpretation of banding patterns have impeded progress. The method has recently been adapted to incorporate high-resolution capillary gel-based electrophoresis (CE-ribotyping, so improving discrimination, accuracy and reproducibility. However, reports to date have all represented single-centre studies and inter-laboratory variability has not been formally measured or assessed. Here, we achieved in a multi-centre setting a high level of reproducibility, accuracy and portability associated with a consensus CE-ribotyping protocol. Local databases were built at four participating laboratories using a distributed set of 70 known PCR-ribotypes. A panel of 50 isolates and 60 electronic profiles (blinded and randomized were distributed to each testing centre for PCR-ribotype identification based on local databases generated using the standard set of 70 PCR-ribotypes, and the performance of the consensus protocol assessed. A maximum standard deviation of only ±3.8bp was recorded in individual fragment sizes, and PCR-ribotypes from 98.2% of anonymised strains were successfully discriminated across four ribotyping centres spanning Europe and North America (98.8% after analysing discrepancies. Consensus CE-ribotyping increases comparability of typing data between centres and thereby facilitates the rapid and accurate transfer of standardized typing data to support future national and international C. difficile surveillance programs.
Álvarez-Pérez, Sergio; Blanco, José L; Martínez-Nevado, Eva; Peláez, Teresa; Harmanus, Celine; Kuijper, Ed; García, Marta E
Clostridium difficile is an emerging and potentially zoonotic pathogen, but its prevalence in most animal species, including exhibition animals, is currently unknown. In this study we assessed the prevalence of faecal shedding of C. difficile by zoo animals, and determined the ribotype, toxin profile and antimicrobial susceptibility of recovered isolates. A total of 200 samples from 40 animal species (36.5% of which came from plains zebra, Equus quagga burchellii) were analysed. C. difficile was isolated from 7 samples (3.5% of total), which came from the following animal species: chimpanzee (Pan troglodytes troglodytes), dwarf goat (Capra hircus), and Iberian ibex (Capra pyrenaica hispanica), with one positive sample each; and plains zebra, with 4 positive samples from 3 different individuals. Most recovered isolates (4/7, 57.1%) belonged to the epidemic PCR ribotype 078, produced toxins A and B, and had the genes encoding binary toxin (i.e. A(+)B(+)CDT(+) isolates). The remaining three isolates belonged to PCR ribotypes 039 (A(-)B(-)CDT(-)), 042 (A(+)B(+)CDT(-)) and 110 (A(-)B(+)CDT(-)). Regardless of their ribotype, all isolates displayed high-level resistance to the fluoroquinolones ciprofloxacin, enrofloxacin and levofloxacin. Some isolates were also resistant to meropenem and/or ertapenem. A ribotype 078 isolate recovered from a male zebra foal initially showed in vitro resistance to metronidazole (MIC ≥ 256 μg/ml), but lost that trait after subculturing on non-selective media. We conclude that zoo animals belonging to different species can carry ribotype 078 and other toxigenic strains of C. difficile showing resistance to antimicrobial compounds commonly used in veterinary and/or human medicine. Copyright © 2014 Elsevier B.V. All rights reserved.
Eckert, C.; Van Broeck, J.; Spigaglia, P.; Burghoffer, B.; Delmée, M.; Mastrantonio, P.; Barbut, F.
This study compared a repetitive-element PCR (rep-PCR) method (DiversiLab system) to PCR ribotyping. The discriminatory power of rep-PCR was 0.997. Among the PCR ribotype 027 isolates tested, different rep types could be distinguished. rep-PCR showed a higher discriminatory power than PCR ribotyping. Nevertheless, this method requires technical skill, and visual interpretation of rep-PCR fingerprint patterns may be difficult.
Holt, H M; Danielsen, T K; Justesen, U S
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 European Committee on Antimicrobial Susceptibility Testing (EUCAST) epidemiological minimum inhibitory concentration (MIC) cut-off values in a routine setting. Metronidazole and vancomycin zone diameters from 2702 isolates were recorded. Fifteen isolates had a metronidazole zone diameter below...... the published breakpoint (vancomycin zone diameter below the published breakpoint (
Kenters, N.; E. Huijskens (Elisabeth); de Wit, S.C.J.; Sanders, I.G.J.M.; J.M. van Rosmalen (Joost); E. Kuijper; Voss, A.
textabstractBackground: In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested
Kenters, N.; Huijskens, E.G.; Wit, S.C.J. de; Sanders, I.; Rosmalen, J. van; Kuijper, E.J.; Voss, A.
BACKGROUND: In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested for their
patients, each infected with a different ribotype.Conclusion: Although these data provide a baseline assessment of outcomes to aid in the design of future studies, the diversity of C. difficile ribotypes within the population must be considered, and additional work with other ribotypes may further explain the association with these outcomes. Keywords: Clostridium difficile, PCR, 027, 014/020
Clayton, J J; McHale-Owen, J
This article reports a significant outbreak of Clostridium difficile ribotype 027 infection in a residential care home in the UK. Five of six affected residents died within one month of diagnosis. Investigation of the facility revealed problems with hand hygiene and environmental cleaning. Affected residents had received a mean of 2.7 antibiotic courses in the two months preceding diagnosis. It is important to recognize that C. difficile outbreaks can occur in residential homes. There is a need for health- and social-care systems to work closely together to assure the safety of people in their care. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Clostridium difficile is an important healthcare-associated pathogen. Hypervirulent strains such as those belonging to ribotype 027 have been widely reported in recent years. A second strain associated with hypervirulence is ribotype 078 and the prevalence of Clostridium difficile infection (CDI) due to this ribotype appears to be increasing. This report describes an outbreak, in which 15cases of CDI due to ribotype 078 were detected in an Irish hospital and from a nursing home in the hospital\\'s catchment area. C. difficile ribotype 078 accounted for 15% of total isolates submitted for ribotyping. The average age of patients with CDI due to ribotype 078 was 76 years. Forty-six percent of patients experienced recurrence of symptoms within eight weeks of diagnosis and CDI was felt to have directly contributed to five of the eight deaths. Use of enhanced DNA fingerprinting identified clusters within the 15 cases and suggested hitherto unrecognised links between some patients with CDI. Such approaches offer the promise to delineate common sources and transmission routes for C. difficile.
Full Text Available We applied whole-genome sequencing to reconstruct the spatial and temporal dynamics underpinning the expansion of Clostridium difficile ribotype 027 in Germany. Based on re-sequencing of genomes from 57 clinical C. difficile isolates, which had been collected from hospitalized patients at 36 locations throughout Germany between 1990 and 2012, we demonstrate that C. difficile genomes have accumulated sequence variation sufficiently fast to document the pathogen's spread at a regional scale. We detected both previously described lineages of fluoroquinolone-resistant C. difficile ribotype 027, FQR1 and FQR2. Using Bayesian phylogeographic analyses, we show that fluoroquinolone-resistant C. difficile 027 was imported into Germany at least four times, that it had been widely disseminated across multiple federal states even before the first outbreak was noted in 2007, and that it has continued to spread since.
Steglich, Matthias; Nitsche, Andreas; von Müller, Lutz; Herrmann, Mathias; Kohl, Thomas A; Niemann, Stefan; Nübel, Ulrich
We applied whole-genome sequencing to reconstruct the spatial and temporal dynamics underpinning the expansion of Clostridium difficile ribotype 027 in Germany. Based on re-sequencing of genomes from 57 clinical C. difficile isolates, which had been collected from hospitalized patients at 36 locations throughout Germany between 1990 and 2012, we demonstrate that C. difficile genomes have accumulated sequence variation sufficiently fast to document the pathogen's spread at a regional scale. We detected both previously described lineages of fluoroquinolone-resistant C. difficile ribotype 027, FQR1 and FQR2. Using Bayesian phylogeographic analyses, we show that fluoroquinolone-resistant C. difficile 027 was imported into Germany at least four times, that it had been widely disseminated across multiple federal states even before the first outbreak was noted in 2007, and that it has continued to spread since.
Carman, Robert J; Genheimer, Christopher W; Rafii, Fatemeh; Park, Miseon; Hiltonsmith, Megan F; Lyerly, David M
To characterize the extent and diversity of moxifloxacin resistance among Clostridium difficile isolates recovered during a predominantly Anaerobe Reference Unit (ARU) ribotype 027-associated nosocomial outbreak of antibiotic associated diarrhea we measured the susceptibility of 34 field isolates and 6 laboratory strains of C. difficile to moxifloxacin. We ribotyped the isolates as well as assaying them by PCR for the metabolic gene, gdh, and the virulence genes, tcdA, tcdB, tcdC, cdtA and cdtB. All the laboratory isolates, including the historical ARU 027 isolate Cd196, were susceptible to moxifloxacin (or=16 microg/mL (high resistance). We sequenced the quinolone resistance determining regions of gyrA (position 71-460) and gyrB (position 1059-1448) from two susceptible laboratory strains, all five isolates with moderate resistance and two highly resistant isolates. Two highly resistant isolates (Pitt 40, ribotype ARU 027 and Pitt 33, ribotype ARU 001) had the same C245T (Thr(82)Delta Ile) mutation. No other changes were seen. Amplification with primer pairs specific for the C245T mutant gyrA and for the wild type gene respectively confirmed all 16 highly resistant ARU 027 isolates, as well as the highly resistant isolates from other ribotypes, had the C245T mutation and that the mutation was absent from all other isolates. Among the five isolates with moderate resistance we found combinations of mutations within gyrA (T128A, Val(43)Delta Asp and G349T, Ala(117)Delta Ser) and gyrB (G1276A, Arg(426)Delta Asn). The G1396A (Glu(466)Delta Lys) mutation was not associated with increased resistance.
Sommer, Trine Nyboe; Ravn, Pernille; Skinhøj, Ida Elisabeth Gjørup
Infection with Clostridium difficile is the primary infective cause of antibiotic-associated diarrhoea. In 2008, a major outbreak of CD027 took place in North Zealand, Denmark. We described this infection in a single medical department. Patients positive for C. difficile enlisted at Medical...... Department O, Herlev Hospital, in 2009 were included and demographic data were recorded. In total, 69 patients were included, average age 83 years, Charlson Comorbidity Score 4. Of all patients 24 died. Further studies are needed in order to treat and minimize infection with C. difficile....
Li, Zhirong; Liu, Xiaolei; Zhao, Jianhong; Xu, Kaiyue; Tian, Tiantian; Yang, Jing; Qiang, Cuixin; Shi, Dongyan; Wei, Honglian; Sun, Suju; Cui, Qingqing; Li, Ruxin; Niu, Yanan; Huang, Bixing
Clostridium difficile is the causative pathogen for antibiotic-related nosocomial diarrhea. For epidemiological study and identification of virulent clones, a new binary typing method was developed for C. difficile in this study. The usefulness of this newly developed optimized 10-loci binary typing method was compared with two widely used methods ribotyping and multilocus sequence typing (MLST) in 189 C. difficile samples. The binary typing, ribotyping and MLST typed the samples into 53 binary types (BTs), 26 ribotypes (RTs), and 33 MLST sequence types (STs), respectively. The typing ability of the binary method was better than that of either ribotyping or MLST expressed in Simpson Index (SI) at 0.937, 0.892 and 0.859, respectively. The ease of testing, portability and cost-effectiveness of the new binary typing would make it a useful typing alternative for outbreak investigations within healthcare facilities and epidemiological research. Copyright © 2018 Elsevier B.V. All rights reserved.
Jensen, M B F; Olsen, K E P; Nielsen, X C
The diagnosis of Clostridium difficile infection (CDI) requires the detection of toxigenic C. difficile or its toxins and a clinical assessment. We evaluated the performance of four nucleic acid amplification tests (NAATs) detecting toxigenic C. difficile directly from faeces compared to routine...... ribotyping and toxinotyping (TT) were performed on culture-positive samples. In parallel, the samples were analysed by four NAATs; two targeting tcdA or tcdB (illumigene® C. difficile and PCRFast® C. difficile A/B) and two multi-target real-time (RT) PCR assays also targeting cdt and tcdC alleles...... characteristic of epidemic and potentially more virulent PCR ribotypes 027, 066 and 078 (GeneXpert® C. difficile/Epi and an 'in-house RT PCR' two-step algorithm). The multi-target assays were significantly more sensitive compared to routine toxigenic culture (p
Hoegh, A M; Nielsen, J B; Lester, A
The purpose of this study was to validate a multiplex real-time PCR assay capable of detecting toxigenic Clostridium difficile and simultaneously identifying C. difficile ribotype 027/ST-1 by targeting the toxin genes tcdA, tcdB and cdtA in one reaction and in a separate reaction identifying the Δ...... to confirm the correct identification of the Δ117 deletion in tcdC and C. difficile ribotype 027/ST-1, respectively. The PCR assay displayed a sensitivity, specificity, PPV and NPV of 99.0%, 97.4%, 87.4% and 99.8%, respectively, compared to toxigenic culture on 665 samples evaluable both by PCR and culture....... Sequencing of tcdC, ribotyping and MLST of cultured isolates validated the genotyping assay and confirmed the ability of the assay to correctly identify C. difficile ribotype 027/ST-1 in our current epidemiological setting. We describe the use of a combination of two separate PCR assays for sensitive...
Ofori, Emmanuel; Ramai, Daryl; Dhawan, Monica; Mustafa, Fareeza; Gasperino, James; Reddy, Madhavi
The epidemiological landscape of Clostridium difficile infection (CDI) has changed over the past 30 years. To review studies of CDI in the community setting. Electronic databases including PubMed, MEDLINE, Embase, Google Scholar, Scopus, ClinicalTrials.gov, and Cochrane Databases were searched for human studies performed between 2000 and 2017 that assessed the epidemiology, risk factors, ribotypes, hospital and intensive care unit outcomes, and management of community-acquired CDI. We also manually searched references to identify additional relevant studies. In total, 39 articles met our inclusion criteria. The incidence of community acquired CDI has almost doubled in the past decade. Approximately half of all cases of CDI are attributed to community origin. Individuals who are younger, female, in the presence of infants, frequently use proton pump inhibitors or specific classes of antibiotics, or live near farms and livestock are at higher risk for community-acquired CDI. Additionally, about 40% of all community-acquired cases require hospitalization, where severity has been linked to hypervirulent ribotypes 027 and 078 with poor outcomes. Emerging data on treatment paradigms have led to the revision of clinical guidelines and two potential vaccines in phase three clinical trials. However, ribotype specific response to current treatment strategies is lacking. Community-acquired CDI represents a growing public health threat and burden on healthcare systems. A multidisciplinary approach will be required to stem the tides. Copyright © 2018. Published by Elsevier Ltd.
Gabriel Adrian Popescu
Full Text Available Aims: To investigate the epidemiology of Clostridium difficile infection in Romanian hospitals. Methods: A survey was conducted at nine hospitals throughout Romania between November 2013 and February 2014. Results: The survey identified 393 patients with Clostridium difficile infection. The median age was 67 years (range: 2-94 years; 56% of patients were aged >65 years. The mean prevalence of Clostridium difficile infection was 5.2 cases per 10.000 patient-days. The highest prevalences were 24.9 and 20 per 10.000 patient-days in hospitals specializing in gastroenterology and infectious diseases, respectively. Clostridium difficile infections were health care-associated in 70.5% patients and community-acquired in 10.2%. The origin was not determined in 19.3%. Clostridium difficile infection was severe in 12.3% of patients, and the in-hospital all-cause mortality was 8.8%. Polymerase chain reaction ribotype 027 had the highest prevalence in all participating hospitals and represented 82.6% of the total ribotyped isolates. The minimum inhibitory concentration of moxifloxacin was >4 μg/mL for 59 of 80 tested isolates (73.8%. Of 59 isolates, 54 were highly resistant to moxifloxacin (minimum inhibitory concentration ≥32 μg/mL, and the majority were polymerase chain reaction ribotype 027 (p<0.0001. Conclusion: The ribotype 027 was the predominant cause of Clostridium difficile infections in Romania. In some specialized hospitals, the prevalence of Clostridium difficile infection was higher than the European mean prevalence, and this demonstrates the need for strict adherence to infection control programs.
A.F. van Belkum (Alex); H. Maas (Hugo); H.A. Verbrugh (Henri); N. van Leeuwen (N.)
textabstractFifty clinical and environmental isolates of Legionella pneumophila were typed serologically and by DNA fingerprinting using arbitrarily primed polymerase chain reaction (AP-PCR). Furthermore, variability in and around ribosomal operons was assessed by conventional ribotyping and
Janezic, Sandra; Zidaric, Valerija; Pardon, Bart
as well as in terms of number of different host species: 078 (14.3% of isolates; 4 hosts), 014/020 (11.6%; 8 hosts); 002 (5.4%; 4 hosts) and 012 (5.4%; 5 hosts). Two animal hosts were best represented; cattle with 31 isolates (20 PCR ribotypes; 7 countries) and pigs with 31 isolates (16 PCR ribotypes; 10......Background: Clostridium difficile is an important cause of intestinal infections in some animal species and animals might be a reservoir for community associated human infections. Here we describe a collection of animal associated C. difficile strains from 12 countries based on inclusion criteria...... of one strain (PCR ribotype) per animal species per laboratory. Results: Altogether 112 isolates were collected and distributed into 38 PCR ribotypes with agarose based approach and 50 PCR ribotypes with sequencer based approach. Four PCR ribotypes were most prevalent in terms of number of isolates...
Koene, M G J; Mevius, D; Wagenaar, J A; Harmanus, C; Hensgens, M P M; Meetsma, A M; Putirulan, F F; van Bergen, M A P; Kuijper, E J
The presence and characteristics of Clostridium difficile were investigated in 839 faecal samples from seven different animal species in the Netherlands. The number of positive samples ranged from 3.4% (cattle) to 25.0% (dogs). Twenty-two different PCR ribotypes were identified. Among 96 isolates, 53% harboured toxin genes. All C. difficile isolates from pigs, cattle and poultry were toxinogenic, whereas the majority of isolates from pet animals consisted of non-toxinogenic PCR ribotypes 010 and 039. Ribotype 012 was most prevalent in cattle and ribotype 078 in pigs. No predominant ribotypes were present in horse and poultry samples. Overall, PCR ribotypes 012, 014 and 078 were the most frequently recovered toxinogenic ribotypes from animal samples. Comparison with human isolates from the Dutch Reference Laboratory for C. difficile at Leiden University Medical Centre (LUMC) showed that these types were also recovered from human hospitalized patients in 2009/2010, encompassing 0.8%, 11.4% and 9.8% of all isolates, respectively. Application of multiple-locus variable-number tandem-repeat analysis indicated a genotypic relation of animal and human ribotype 078 strains, but a clear genotypic distinction for ribotypes 012 and 014. We conclude that toxinogenic C. difficile PCR ribotypes found in animals correspond to PCR ribotypes associated with human disease in hospitalized patients in the Netherlands. Contrary to PCR ribotype 078, significant genetic differences were observed between animal and human PCR ribotype 012 and 014 isolates. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.
Rizzardi, Kristina; ?kerlund, Thomas
Clostridium difficile strains were typed by a newly developed MALDI-TOF method, high molecular weight typing, and compared to PCR ribotyping. Among 500 isolates representing 59 PCR ribotypes a total of 35 high molecular weight types could be resolved. Although less discriminatory than PCR ribotyping, the method is extremely fast and simple, and supports for cost-effective screening of isolates during outbreak situations.
Sofie M van Dorp
Full Text Available It has been suggested that the high incidence of ribotype 078 Clostridium difficile infections (CDI in the Netherlands is related to pig farming.We used data of hospitalised CDI patients (>2yrs of age diagnosed between May 2009 and May 2015 in 26 hospitals participating in a national sentinel surveillance. We compared clinical and geographical characteristics of 078 CDI to other CDI. We investigated the association between 078 CDI incidence and four indicators of pig farming (piglet, pig, piglet farm and pig farm density by mixed-effects Poisson regression. We used a space-time permutation model to search for community-onset 078 CDI clusters (using SaTScan.A total of 4,691 CDI were identified. Ribotype 078 was isolated in 493 of 3,756 patients (13.1% including a typing result. These patients had slightly higher community-onset disease and a 35% increase of 30-day mortality compared to non-078 CDI patients. The pooled overall and 078 incidence rates were 2.82 (95% CI, 2.42-3.29 and 0.26 (95% CI, 0.21-0.31 CDI per 10,000 patients-days respectively. Hospital 078 CDI incidence was not associated with provincial pig (IRR, 0.98; 95% CI, 0.89-1.08, piglet (IRR, 0.95; 95% CI, 0.75-1.19, pig farm (IRR, 1.08; 95% CI, 0.84-1.39, or piglet farm density (IRR, 1.00; 95% CI, 0.56-1.79. No clusters of community-onset ribotype 078 CDI were found.Our results do not indicate that the ribotype 078 CDI incidence in hospitals is related to pig (farm or piglet (farm density. However, transmission beyond provincial borders or in non-hospitalised patients cannot be excluded.
Yvette H van Beurden
Full Text Available An outbreak of Clostridium difficile ribotype 027 infection (CDI occurred at an university hospital, involving 19 departments. To determine what hospital-associated factors drove the outbreak of this particular strain we performed a case-control study.Cases (n = 79, diagnosed with CDI due to C. difficile ribotype 027 were matched for age and treating medical specialty to four control patients (n = 316. Patients diagnosed with CDI due to other ribotypes were included as a second control group. A random selection of C. difficile ribotype 027 strains (n = 10 was genotyped by Whole Genome Sequencing (WGS.WGS showed the outbreak was likely caused by a single strain of C. difficile (two or less single-nucleotide variants between isolates. Ninety-five percent of cases had used antibiotics, compared to 56% of controls. Previous admission to the intensive care unit (ICU (OR: 2.4, 95% CI 1.0-5.6, longer length of stay (LOS, and recent hospital admission were associated with CDI ribotype 027. Cases were less likely to have been admitted to a ward with a known isolated CDI patient (OR: 0.2, 95% CI 0.1-0.6. Analysis of patients who stayed at the ICU (35 cases; 51 controls, indicated that the use of selective decontamination of the digestive tract (SDD and a longer LOS in the ICU were associated with CDI risk.In this large outbreak, any antibiotic use, including SDD use, appeared as a prerequisite for acquisition of the outbreak strain. The role of use of SDD and prolonged stay on the ICU could not be disentangled, but both factors can play a biologically plausible role in C. difficile acquisition and infection.
Senchyna, Fiona; Gaur, Rajiv L; Gombar, Saurabh; Truong, Cynthia Y; Schroeder, Lee F; Banaei, Niaz
There is no stand-alone Clostridium difficile diagnostic that can sensitively and rapidly detect fecal free toxins. We investigated the performance of the C. difficile PCR cycle threshold ( C T ) for predicting free toxin status. Consecutive stool samples ( n = 312) positive for toxigenic C. difficile by the GeneXpert C. difficile /Epi tcdB PCR assay were tested with the rapid membrane C. Diff Quik Chek Complete immunoassay (RMEIA). RMEIA toxin-negative samples were tested with the cell cytotoxicity neutralization assay (CCNA) and tgcBIOMICS enzyme-linked immunosorbent assay (ELISA). Using RMEIA alone or in combination with CCNA and/or ELISA as the reference method, the accuracy of C T was measured at different C T cutoffs. Using RMEIA as the reference method, a C T cutoff of 26.35 detected toxin-positive samples with a sensitivity, specificity, positive predictive value, and negative predictive value of 96.0% (95% confidence interval [CI], 90.2% to 98.9%), 65.9% (95% CI, 59.0% to 72.2%), 57.4% (95% CI, 52.7% to 62%), and 97.1% (95% CI, 92.8% to 98.9), respectively. Inclusion of CCNA in the reference method improved C T specificity to 78.0% (95% CI, 70.7% to 84.2%). Intercartridge lot C T variability measured as the average coefficient of variation was 2.8% (95% CI, 1.2% to 3.2%). Standardizing the input stool volume did not improve C T toxin specificity. The median C T values were not significantly different between stool samples with Bristol scores of 5, 6, and 7, between pediatric and adult samples, or between presumptive 027 and non-027 strains. In addition to sensitively detecting toxigenic C. difficile in stool, on-demand PCR may also be used to accurately predict toxin-negative stool samples, thus providing additional results in PCR-positive stool samples to guide therapy. Copyright © 2017 American Society for Microbiology.
Full Text Available Clostridium difficile colonization in pig intestine has been a public health concern. We analyzed C. difficile prevalence among piglets in Japan to clarify their origin and extent of the associated risk by using molecular and microbiological methods for both swine and human clinical isolates and foreign isolates. C. difficile was isolated from 120 neonatal piglet faecal samples. Toxin gene profile, antimicrobial susceptibilities, PCR ribotype, and multiple-locus variable-number tandem-repeat analysis (MLVA type of swine isolates were determined and compared with those of human clinical and foreign isolates. One-hundred C. difficile strains were isolated from 69 (57.5% samples, and 61 isolates (61% were toxin gene-positive. Some isolates were resistant to antimicrobials, contributing to antibiotic-associated diarrhoea by C. difficile. These results suggest that C. difficile, prevalent among Japanese pigs, is a potential risk for antibiotic-associated diarrhoea. Furthermore, PCR ribotype 078 (12 isolates, which has been linked to multiple outbreaks worldwide, was the third-most frequently isolated of the 14 PCR ribotypes identified. Moreover, MLVA revealed that all 12 PCR ribotype 078 isolates were genetically related to European PCR ribotype 078 strains found in both humans and pigs. To date, in Japan, many breeding pigs have been imported from European countries. The genetic relatedness of C. difficile isolates of Japanese swine origin to those of European origin suggests that they were introduced into Japan via imported pigs.
Janet Y Nale
Full Text Available The hypervirulent Clostridium difficile ribotype 027 can be classified into subtypes, but it unknown if these differ in terms of severity of C. difficile infection (CDI. Genomic studies of C. difficile 027 strains have established that they are rich in mobile genetic elements including prophages. This study combined physiological studies, electron microscopy analysis and molecular biology to determine the potential role of temperate bacteriophages in disease and diversity of C. difficile 027.We induced prophages from 91 clinical C. difficile 027 isolates and used transmission electron microscopy and pulsed-field gel electrophoresis to characterise the bacteriophages present. We established a correlation between phage morphology and subtype. Morphologically distinct tailed bacteriophages belonging to Myoviridae and Siphoviridae were identified in 63 and three isolates, respectively. Dual phage carriage was observed in four isolates. In addition, there were inducible phage tail-like particles (PT-LPs in all isolates. The capacity of two antibiotics mitomycin C and norfloxacin to induce prophages was compared and it was shown that they induced specific prophages from C. difficile isolates. A PCR assay targeting the capsid gene of the myoviruses was designed to examine molecular diversity of C. difficile myoviruses. Phylogenetic analysis of the capsid gene sequences from eight ribotypes showed that all sequences found in the ribotype 027 isolates were identical and distinct from other C. difficile ribotypes and other bacteria species.A diverse set of temperate bacteriophages are associated with C. difficile 027. The observed correlation between phage carriage and the subtypes suggests that temperate bacteriophages contribute to the diversity of C. difficile 027 and may play a role in severity of disease associated with this ribotype. The capsid gene can be used as a tool to identify C. difficile myoviruses present within bacterial genomes.
Bacci, S; St-Martin, G; Olesen, B
We report an outbreak of Clostridium difficile PCR ribotype 027 in Denmark. The outbreak includes to date 73 cases from the area north of Copenhagen, but there may be related cases elsewhere in Zealand. Most infections are healthcare-associated and in patients who previously received antibiotic t...... in the involved hospitals have been reinforced. Nationwide, microbiological laboratories were alerted to the outbreak and encouraged to send isolates for toxin profiling and PCR ribotyping....
Álvarez-Pérez, S; Blanco, J L; Peláez, T; Lanzarot, M P; Harmanus, C; Kuijper, E; García, M E
To longitudinally assess the shedding of antimicrobial resistant Clostridium difficile strains by clinically healthy dogs raised at breeding facilities. 18 puppies from three different litters (#1, 2 and 3) were sampled weekly from parturition to day 20-55 postpartum. Faecal samples from the mothers of litters #2 and 3 were also available for analysis. Bacterial isolates were ribotyped, tested for in vitro antimicrobial susceptibility and further characterised. C. difficile was recovered from all sampled animals of litters #1 and 2, and a third of puppies from litter #3, but marked differences in C. difficile recovery were detected in different age groups (0-100%). Recovered PCR ribotypes included 056 (22 isolates), 010 (6 isolates), 078 and 213 (2 isolates each), and 009 and 020 (1 isolate each). Different ribotypes were shed by four individual animals. Regardless of their origin and ribotype, all isolates demonstrated full resistance to levofloxacin. Additionally, all but one isolate (belonging to ribotype 078) were resistant to ertapenem, and all ribotype 010 isolates displayed high-level resistance to clindamycin, clarithromycin and erythromycin. A single ribotype 078 isolate showed metronidazole heteroresistance. Healthy dogs can shed antimicrobial-resistant C. difficile strains. © 2014 British Small Animal Veterinary Association.
Abdel-Glil, Mostafa Y; Thomas, Prasad; Schmoock, Gernot; Abou-El-Azm, Kamel; Wieler, Lothar H; Neubauer, Heinrich; Seyboldt, Christian
C. difficile has been recognized as a potential zoonotic agent encouraging investigations of C. difficile prevalence and ribotypes in animals. Here we report the prevalence and diversity of Egyptian C. difficile in I) samples from healthy poultry (n = 50), II) samples from diseased poultry (n = 54), and III) poultry meat (n = 150). Thirteen isolates were obtained from seven healthy and five diseased animals, but no C. difficile was cultured from poultry meat. The isolated C. difficile strains belonged to 3 different PCR-ribotypes (039/2, 205 and 001/FLI01). The detection of strains related to RT 001 known for its ability to cause disease in humans makes poultry a potential reservoir for pathogenic C. difficile. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Andrés-Lasheras, S; Bolea, R; Mainar-Jaime, R C; Kuijper, E; Sevilla, E; Martín-Burriel, I; Chirino-Trejo, M
To determine the presence of Clostridium difficile on fattening pig farms in north-eastern Spain. Twenty-seven farms were sampled. Pools of pig faecal samples (n = 210), samples of intestinal content from common farm pest species (n = 95) and environment-related samples (n = 93) were collected. Isolates were tested for toxin genes of C. difficile, and typed by PCR-ribotyping and toxinotyping. The minimal inhibitory concentrations of six antimicrobial agents were determined using Etest. Thirty-four isolates were obtained from 12 farms, and 30 (88·2%) had toxin genes. Seven ribotypes were identified. Ribotype 078 and its variant 126 were predominant (52·9%). The same ribotypes were isolated from different animal species on the same farm. None of the isolates were resistant to metronidazole or vancomycin. Clostridium difficile was common within the pig farm environment. Most of the positive samples came from pest species or were pest-related environmental samples. Pest species were colonized with toxigenic and antimicrobial-resistant C. difficile strains of the same ribotypes that are found in humans and pigs. Rodents and pigeons may transmit toxigenic and antimicrobial-resistant C. difficile strains that are of the same ribotypes as those occuring in humans. © 2016 The Society for Applied Microbiology.
Full Text Available Clostridium difficile is one of the most important human and animal pathogens. However, the bacterium is ubiquitous and can be isolated from various sources. Here we report the prevalence and characterization of C. difficile in less studied environmental samples, puddle water (n = 104 and soil (n = 79. C. difficile was detected in 14.4% of puddle water and in 36.7% of soil samples. Environmental strains displayed antimicrobial resistance patterns comparable to already published data of human and animal isolates. A total of 480 isolates were grouped into 34 different PCR ribotypes. More than half of these (52.9%; 18 of 34 were already described in humans or animals. However, 14 PCR ribotypes were new in our PCR ribotype library and all but one were non-toxigenic. The multilocus sequence analysis of these new PCR ribotypes revealed that non-toxigenic environmental isolates are phylogenetically distinct and belong to three highly divergent clades, two of which have not been described before. Our data suggest that environment is a potential reservoir of genetically diverse population of C. difficile.
Spigaglia, Patrizia; Barbanti, Fabrizio; Morandi, Matteo; Moro, Maria Luisa; Mastrantonio, Paola
A laboratory diagnosis survey of Clostridium difficile infection (CDI) was performed in Italy in 2012-2013. Questionnaires from 278 healthcare settings from 15 regions of Italy were collected and analysed. Eighty seven percent of the laboratories declared to routinely perform CDI diagnosis, 99% of them only after the clinician's request. Among the 216 laboratories providing information on the size of the hospitals in which they were located, 65 had more than 500 beds (large hospitals), while 151 had less than 500 beds (small hospitals). The average percentage of positive tests for C. difficile toxins was 12.2%. Almost half of the laboratories (42%) used immunoenzymatic assay (EIA) for Tox A/B as a stand-alone method, while only 34% used an algorithm for CDI as indicated by the European guidelines. A low percentage of laboratories performed molecular assays or C. difficile culture, 25% and 29%, respectively. Most laboratories (161/278) declared to type C. difficile strains, the majority in collaboration with a reference laboratory. Among the 103 C. difficile clinical isolates collected during the study, 31 different PCR-ribotypes were identified. PCR-ribotype 356/607 (27%) was predominant, followed by 018 (12%). These two PCR-ribotypes show 87.5% of similarity in ribotyping profile. PCR-ribotypes 027 and 078 represented 8% and 4% of the strains, respectively. Four PCR-ribotypes (027, 033, 078 and 126) were positive for the binary toxin CDT. In particular, PCR-ribotype 033 produces only CDT, and it has recently been associated with symptomatic cases. The majority of strains were multidrug resistant. In particular, all strains PCR-ribotypes 356/607 and 018 were resistant to moxifloxacin, rifampicin, erythromycin and clindamycin. The results obtained highlight the need to raise awareness to the microbiological diagnosis of CDI among clinicians and to implement and harmonize diagnostic methods for CDI in Italian laboratories in the perspective of a future national
Hirvonen, Jari J; Mentula, Silja; Kaukoranta, Suvi-Sirkku
We evaluated a new automated homogeneous PCR assay to detect toxigenic Clostridium difficile, the GenomEra C. difficile assay (Abacus Diagnostica, Finland), with 310 diarrheal stool specimens and with a collection of 33 known clostridial and nonclostridial isolates. Results were compared with toxigenic culture results, with discrepancies being resolved by the GeneXpert C. difficile PCR assay (Cepheid). Among the 80 toxigenic culture-positive or GeneXpert C. difficile assay-positive fecal specimens, 79 were also positive with the GenomEra C. difficile assay. Additionally, one specimen was positive with the GenomEra assay but negative with the confirmatory methods. Thus, the sensitivity and specificity were 98.8% and 99.6%, respectively. With the culture collection, no false-positive or -negative results were observed. The analytical sensitivity of the GenomEra C. difficile assay was approximately 5 CFU per PCR test. The short hands-on (<5 min for 1 to 4 samples) and total turnaround (<1 h) times, together with the high positive and negative predictive values (98.8% and 99.6%, respectively), make the GenomEra C. difficile assay an excellent option for toxigenic C. difficile detection in fecal specimens.
Moono, Peter; Lim, Su Chen; Riley, Thomas V
Clostridium difficile is a well-established hospital pathogen. Recently, it has been detected increasingly in patients without hospital contact. Given this rise in community associated infections with C. difficile, we hypothesized that the environment could play an important role in transmission of spores outside the hospital. Lawn samples (311) collected in public spaces in the metropolitan area of Perth, Western Australia, from February to June 2016 were cultured for C. difficile. C. difficile was isolated from the samples by direct and enrichment culture, and characterized by standard molecular methods using toxin gene PCR and ribotyping. The overall prevalence of C. difficile was 59%, new lawn (≤4 months old) was twice as likely as old lawn (>4 months old) to test positive (OR = 2.3; 95%CI 1.16-4.57, p = 0.015) and 35 C. difficile ribotypes were identified with toxigenic ribotype 014/020 (39%) predominating. The highest viable count from lawn soil samples was 1200 CFU/g. These results show that lawns in Perth, Western Australia, harbor toxigenic C. difficile, an important finding. The source of lawn contamination is likely related to modern practice of producing "roll-out" lawn. Further work should focus on identifying specific management practices that lead to C. difficile contamination of lawn to inform prevention and control measures.
Bacci, S; St-Martin, G; Olesen, B
We report an outbreak of Clostridium difficile PCR ribotype 027 in Denmark. The outbreak includes to date 73 cases from the area north of Copenhagen, but there may be related cases elsewhere in Zealand. Most infections are healthcare-associated and in patients who previously received antibiotic t...
Søes, Lillian M; Brock, Inger; Torpdahl, Mia
Increasing rates of Clostridium difficile-associated diarrhoea (CDAD) with an unusual, severe course have been reported in Canada, USA and several European countries since 2003. A new virulent strain, PCR ribotype 027 (CD027), is associated with this increase. We report the first Danish case...
Collins, Deirdre A; Elliott, Briony; Riley, Thomas V
Since the early 2000s, Clostridium difficile has emerged as a major international pathogen. Recently, strains of C. difficile in circulation appear to be changing, with greater diversity, leading to challenges for diagnostics and surveillance. Currently molecular diagnostic methods are favoured for their high sensitivity and rapid processing times; however, a number of issues still exist with molecular tests, in particular high cost, low clinical specificity and failure to detect some variant C. difficile strains. Molecular typing methods are used to determine the continually evolving epidemiology of C. difficile infection. Typing methods including PCR ribotyping and pulsed field gel electrophoresis are currently popular in Europe and North America, respectively, while high-throughput next-generation sequencing is likely to become more widely used in years to come. This review discusses current molecular detection and typing techniques for C. difficile.
Lim, S C; Foster, N F; Elliott, B; Riley, T V
The incidence of community-associated Clostridium difficile infection (CA-CDI) in Australia has increased since mid-2011. With reports of clinically important C. difficile strains being isolated from retail foods in Europe and North America, a foodborne source of C. difficile in cases of CA-CDI is a possibility. This study represents the first to investigate the prevalence and genotypes of C. difficile in Australian retail vegetables. A total of 300 root vegetables grown in Western Australia (WA) were collected from retail stores and farmers' markets. Three vegetables of the same kind bought from the same store/market were treated as one sample. Selective enrichment culture, toxin profiling and PCR ribotyping were performed. Clostridium difficile was isolated from 30% (30/100) of pooled vegetable samples, 55·6% of organic potatoes, 50% of nonorganic potatoes, 22·2% of organic beetroots, 5·6% of organic onions and 5·3% of organic carrots. Over half (51·2%, 22/43) the isolates were toxigenic. Many of the ribotypes of C. difficile isolated were common among human and Australian animals. Clostridium difficile could be found commonly on retail root vegetables of WA. This may be potential sources for CA-CDI. This study enhances knowledge of possible sources of C. difficile in the Australian community, outside the hospital setting. © 2017 The Society for Applied Microbiology.
High-resolution genotyping of Listeria monocytogenes by fluorescent amplified fragment length polymorphism analysis compared to pulsed-field gel electrophoresis, random amplified polymorphic DNA analysis, ribotyping, and PCR-restriction fragment length polymorphism analysis
Vogel, Birte Fonnesbech; Fussing, V.; Ojeniyi, B.
of different origin. The AFLP technique was compared with three other molecular typing methods - ribotyping, random amplified polymorphic DNA analysis (RAPD), and pulsed-field gel electrophoresis (PFGE) - in terms of discriminatory ability. PCR-restriction fragment length polymorphism was included...... for virulence gene allele characterization. The 96 L. monocytogenes strains were divided into two major clusters by AFLP fingerprinting at a similarity level of 82% in concordance with the results of PFGE, RAPD, and ribotyping. One main cluster consisted of all of the 24 L. monocytogenes hly allele 1 strains...
Putsathit, Papanin; Kiratisin, Pattarachai; Ngamwongsatit, Puriya; Riley, Thomas V
Clostridium difficile is the aetiological agent in ca. 20% of cases of antimicrobial-associated diarrhoea in hospitalised adults. Diseases caused by this organism range from mild diarrhoea to occasional fatal pseudomembranous colitis. The epidemiology of C. difficile infection (CDI) has changed notably in the past decade, following epidemics in the early 2000s of PCR ribotype (RT) 027 infection in North America and Europe, where there was an increase in disease severity and mortality. Another major event has been the emergence of RT 078, initially as the predominant ribotype in production animals in the USA and Europe, and then in humans in Europe. Although there have been numerous investigations of the epidemiology of CDI in North America and Europe, limited studies have been undertaken elsewhere, particularly in Asia. Antimicrobial exposure remains the major risk factor for CDI. Given the high prevalence of indiscriminate and inappropriate use of antimicrobials in Asia, it is conceivable that CDI is relatively common among humans and animals. This review describes the level of knowledge in Thailand regarding C. difficile detection methods, prevalence and antimicrobial susceptibility profile, as well as the clinical features of, treatment options for and outcomes of the disease. In addition, antimicrobial usage in livestock in Thailand will be reviewed. A literature search yielded 18 studies mentioning C. difficile in Thailand, a greater number than from any other Asian country. It is possible that the situation in Thailand in relation to CDI may mirror the situation in other developing Asians countries. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.
Cheng, Allen C; Collins, Deirdre A; Elliott, Briony; Ferguson, John K; Paterson, David L; Thean, Sara; Riley, Thomas V
Clostridium difficile rose in prominence in the early 2000s with large-scale outbreaks of a particular binary toxin-positive strain, ribotype 027, in North America and Europe. In Australia outbreaks of the same scale had not and have not been seen. A survey of C. difficile across Australia was performed for 1 month in 2010. A collection of 330 C. difficile isolates from all States and Territories except Victoria and the Northern Territory was amassed. PCR ribotyping revealed a diverse array of strains. Ribotypes 014/020 (30.0%) and 002 (11.8%) were most common, followed by 054 (4.2%), 056 (3.9%), 070 (3.6%) and 005 (3.3%). The collection also contained few binary toxin positive strains, namely 027 (0.9%), 078 (0.3%), 244 (0.3%), 251 (0.3%) and 127 (0.3%). The survey highlights the need for vigilance for emerging strains in Australia, and gives an overview of the molecular epidemiology of C. difficile in Australia prior to an increase in incidence noted from mid-2011. Copyright © 2016 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.
Schoster, Angelika; Arroyo, Luis; Staempfli, Henry
Clostridium difficile and Clostridium perfringens are important causes of equine colitis but can also be found in healthy individuals. Epidemiologic information is restricted to cross-sectional studies of fecal shedding with little information on prevalence in gastrointestinal compartments other...... than feces and variability in shedding over time. The objectives were to investigate the presence of C. difficile and C. perfringens in healthy horses over time and assess prevalence in different gastrointestinal compartments. Feces were collected monthly from 25 horses for one year. Ingesta were...... collected from nine GI compartments of a separate group of 15 euthanized horses. Selective enrichment culture was performed, followed by toxin gene detection and ribotyping (C. difficile) and multiplex PCR (C. perfringens). Toxigenic C. difficile was isolated from 15/275 (5.5%) samples from 10/25 (40...
Knetsch, C W; Lawley, T D; Hensgens, M P; Corver, J; Wilcox, M W; Kuijper, E J
Molecular typing is an essential tool to monitor Clostridium difficile infections and outbreaks within healthcare facilities. Molecular typing also plays a key role in defining the regional and global changes in circulating C. difficile types. The patterns of C. difficile types circulating within Europe (and globally) remain poorly understood, although international efforts are under way to understand the spatial and temporal patterns of C. difficile types. A complete picture is essential to properly investigate type-specific risk factors for C. difficile infections (CDI) and track long-range transmission. Currently, conventional agarose gel-based polymerase chain reaction (PCR) ribotyping is the most common typing method used in Europe to type C. difficile. Although this method has proved to be useful to study epidemiology on local, national and European level, efforts are made to replace it with capillary electrophoresis PCR ribotyping to increase pattern recognition, reproducibility and interpretation. However, this method lacks sufficient discriminatory power to study outbreaks and therefore multilocus variable-number tandem repeat analysis (MLVA) has been developed to study transmission between humans, animals and food. Sequence-based methods are increasingly being used for C. difficile fingerprinting/typing because of their ability to discriminate between highly related strains, the ease of data interpretation and transferability of data. The first studies using whole-genome single nucleotide polymorphism typing of healthcare-associated C. difficile within a clinically relevant timeframe are very promising and, although limited to select facilities because of complex data interpretation and high costs, these approaches will likely become commonly used over the coming years.
Avberšek, Jana; Pirš, Tina; Pate, Mateja; Rupnik, Maja; Ocepek, Matjaž
Diversity of Clostridium difficile in different age groups of goats (n = 109) and sheep (n = 105) was investigated. C. difficile was detected in 9.2% of goats and 5.7% of sheep. None of the adult animals were positive. Isolates belonged to four toxinotypes (0, V, XIa, XII), six PCR-ribotypes (010, 014/020, 045, 056, SLO 061, SLO 151) and six pulsotypes. PCR-ribotypes 010, 014/020, 045 and 056 were found previously in other animal species and humans in Slovenia. Additionally, three pulsotypes were indistinguishable from restriction patterns in our PFGE database of animal isolates. All strains were susceptible to metronidazol, vancomycin, moxifloxacin, and with the exception of a single non-toxigenic strain also to clindamycin and erythromycin. While all strains were resistant to ciprofloxacin and levofloxacin, oxacillin-resistance was observed only in strains of PCR-ribotype 045. This first study on C. difficile in small ruminants in Slovenia revealed the evidence of age-related shedding as the highest was demonstrated in neonatal goats and sheep aged up to 16 days. Copyright © 2014 Elsevier Ltd. All rights reserved.
Full Text Available Clostridium difficile causes antibiotic-associated diarrhoea and pseudomembranous colitis. The main virulence factors of C. difficile are the toxins A (TcdA and B (TcdB. A third toxin, called binary toxin (CDT, can be detected in 17% to 23% of strains, but its role in human disease has not been clearly defined. We report six independent cases of patients with diarrhoea suspected of having C. difficile infection due to strains from toxinotype XI/PCR ribotype 033 or 033-like, an unusual toxinotype/PCR ribotype positive for CDT but negative for TcdA and TcdB. Four patients were considered truly infected by clinicians and were specifically treated with oral metronidazole. One of the cases was identified during a prevalence study of A−B−CDT+ strains. In this study, we screened a French collection of 220 nontoxigenic strains and found only one (0.5% toxinotype XI/PCR ribotype 033 or 033-like strain. The description of such strains raises the question of the role of binary toxin as a virulence factor and could have implications for laboratory diagnostics that currently rarely include testing for binary toxin.
Full Text Available Community-associated Clostridium difficile infection (CDI appears to be an increasing problem. Reported carriage rates by C. difficile are debatable with suggestions that primary asymptomatic carriage is associated with decreased risk of subsequent diarrhoea. However, knowledge of potential reservoirs and intestinal carriage rates in the community, particularly in the elderly, the most susceptible group, is limited. We have determined the presence of C. difficile in the faeces of a healthy elderly cohort living outside of long-term care facilities (LCFs in the United Kingdom.Faecal samples from 149 community-based healthy elderly volunteers (median age 81 years were screened for C. difficile using direct (Brazier's CCEY and enrichment (Cooked Meat broth culture methods and a glutamate dehydrogenase (GDH immunoassay. Isolates were PCR-ribotyped and analysed for toxin production and the presence of toxin genes.Of 149 faecal samples submitted, six (4% were found to contain C. difficile. One particular sample was positive by both the GDH immunoassay and direct culture, and concurrently produced two distinct strain types: one toxigenic and the other non-toxigenic. The other five samples were only positive by enrichment culture method. Overall, four C. difficile isolates were non-toxigenic (PCR-ribotypes 009, 026 (n = 2 and 039, while three were toxigenic (PCR-ribotypes 003, 005 and 106. All individuals who had a positive culture were symptom-free and none of them had a history of CDI and/or antibiotics use in the 3 month period preceding recruitment.To our knowledge, this is the first study of the presence of C. difficile in healthy elderly community-dwelling individuals residing outside of LCFs. The observed carriage rate is lower than that reported for individuals in LCFs and interestingly no individual carried the common epidemic strain PCR-ribotype 027 (NAP1/BI. Further follow-up of asymptomatic carriers in the community, is required to
Agaronov, Maksim; Karak, Soma G; Maldonado, Yanice; Tetreault, Janice; Aslanzadeh, Jaber
The need for rapid diagnosis of Clostridium difficile (C. difficile) associated infection in a clinical microbiology laboratory has provided the stimulus for new diagnostic tests and testing protocols. A two-test algorithm has been proposed using assays such as Quik Chek Complete, which detects both C. difficile glutamate dehydrogenase (GDH) and C. difficile toxins A and B, followed by reflex testing of samples having inconclusive results (GDH positive and toxin negative) with PCR for identification of toxin gene specific DNA. The goal of this study was to compare the outcome and efficiency of PCR assays, BD GeneOhm and GeneXpert, for detecting C. difficile toxin B gene in samples that have tested indeterminate for C. difficile by the Quik Chek Complete test. Over a three-month period, a total of 41 cases tested indeterminate by Quik Chek Complete test and were retested by the aforementioned PCR assays. Out of the 41 samples, 36 had matching results in both assays; 19 negative samples and 17 positive samples. In terms of efficiency, GeneXpert was user-friendly and had a turnaround time (TAT) of 45 minutes with two-minute specimen processing compared to BD GeneOhm which had a TAT of 75 to 90 minutes.
Full Text Available Clostridium difficile is an important cause of disease in Canada; however, little information is available about the disease in the Maritime provinces. The objective of the present study was to characterize C difficile isolates obtained from people hospitalized with C difficile infection in Prince Edward Island. One hundred twenty-six C difficile ELISA toxin-positive stool samples were obtained and cultured using an enrichment protocol. C difficile was isolated from 105 of 126 (83% samples. Twenty-two different ribotypes were identified. The most common ribotype, ribotype W, was a North American pulsotype 2 (NAP2, toxinotype 0 strain, which represented 18% of isolates. The next most common ribotype was a NAP1, toxinotype III strain, which accounted for 11% of isolates. Ribotype 027/NAP1 only accounted for five (4.7% isolates. Forty-five per cent of isolates possessed genes encoding production of binary toxin. Three different ribotypes, all NAP1, toxinotype III strains, had a frameshift mutation in the tcdC gene (Δ117, while one isolate (ribotype 078, NAP4, toxinotype V had a truncating mutation (C184T in the tcdC gene.
High-resolution genotyping of Listeria monocytogenes by fluorescent amplified fragment length polymorphism analysis compared to pulsed-field gel electrophoresis, random amplified polymorphic DNA analysis, ribotyping, and PCR-restriction fragment length polymorphism analysis
Vogel, Birte Fonnesbech; Fussing, V.; Ojeniyi, B.
The purpose of this study was to evaluate fluorescent amplified fragment length polymorphism (AFLP) analysis for the inter- and intraspecies differentiation of a collection of 96 strains of Listeria monocytogenes and 10 non- L. monocytogenes strains representing six other Listeria species...... of different origin. The AFLP technique was compared with three other molecular typing methods - ribotyping, random amplified polymorphic DNA analysis (RAPD), and pulsed-field gel electrophoresis (PFGE) - in terms of discriminatory ability. PCR-restriction fragment length polymorphism was included....... Isolates with identical DNA profiles were distributed across the spectrum of origin. It was not possible to associate certain types with specific food sectors or clinical cases, which is indicative of the spread of L. monocytogenes clones across species. Overall, AFLP fingerprinting was suitable...
Agatha N. Jassem
Full Text Available Background. Clostridium difficile is a major cause of gastrointestinal illness. Epidemic NAP1 strains contain toxins A and B, a deletion in repressor tcdC, and a binary toxin. Objectives. To determine the molecular epidemiology of C. difficile in British Columbia and compare between two time points in one region. Methods. C. difficile isolates from hospital and community laboratories (2008 and one Island Health hospital laboratory (2013 were characterized by pulsed-field gel electrophoresis, PCR-ribotyping, toxin possession, tcdC genotype, and antimicrobial susceptibility. Results. In 2008, 42.7% of isolates had NAP1 designation. Hospital-collected isolates were associated with older patients and more NAP1 types. Unlike other isolates, most NAP1 isolates possessed binary toxin and a 19 bp loss in tcdC. All isolates were susceptible to metronidazole and vancomycin. A 2013 follow-up revealed a 28.9% decrease in NAP1 isolates and 20.0% increase in isolates without NAP designation in one region. Then, community-associated cases were seen in younger patients, while NAP types were evenly distributed. Isolates without NAP designation did not cluster with a PFGE pattern or ribotype. Conclusions. Evaluation of C. difficile infections within British Columbia revealed demographic associations, epidemiological shifts, and characteristics of strain types. Continuous surveillance of C. difficile will enable detection of emerging strains.
Zainul, N H; Ma, Z F; Besari, A; Siti Asma, H; Rahman, R A; Collins, D A; Hamid, N; Riley, T V; Lee, Y Y
Little is known about Clostridium difficile infection (CDI) in Asia. The aims of our study were to explore (i) the prevalence, risk factors and molecular epidemiology of CDI and colonization in a tertiary academic hospital in North-Eastern Peninsular Malaysia; (ii) the rate of carriage of C. difficile among the elderly in the region; (iii) the awareness level of this infection among the hospital staffs and students. For stool samples collected from hospital inpatients with diarrhea (n = 76) and healthy community members (n = 138), C. difficile antigen and toxins were tested by enzyme immunoassay. Stool samples were subsequently analyzed by culture and molecular detection of toxin genes, and PCR ribotyping of isolates. To examine awareness among hospital staff and students, participants were asked to complete a self-administered questionnaire. For the hospital and community studies, the prevalence of non-toxigenic C. difficile colonization was 16% and 2%, respectively. The prevalence of CDI among hospital inpatients with diarrhea was 13%. Out of 22 C. difficile strains from hospital inpatients, the toxigenic ribotypes 043 and 017 were most common (both 14%). In univariate analysis, C. difficile colonization in hospital inpatients was significantly associated with greater duration of hospitalization and use of penicillin (both P < 0·05). Absence of these factors was a possible reason for low colonization in the community. Only 3% of 154 respondents answered all questions correctly in the awareness survey. C. difficile colonization is prevalent in a Malaysian hospital setting but not in the elderly community with little or no contact with hospitals. Awareness of CDI is alarmingly poor.
zahra Esfandiari; Mohammad Jalali; Hamid Ezzatpanah; Scott Weese; Mohammad Chamani
Introduction: With regard to increasing of community associated Clostridium difficile infection in recent years, the probable transmission of Clostridium difficile from food to human was supposed. Most of reports on this issue were allocated to examine the prevalence of Clostridium difficile in red meat. The current study aimed at examination of the prevalence of Clostridium difficile in beef meat. Materials and methods: A total of 100 beef meat samples includi...
Neuendorf, Martina; Guadarrama-Gonzalez, Raquel; Lamik, Birgit; MacKenzie, Colin R
New molecular methods of detecting Clostridium difficile infection (CDI) provide the routine lab with a sensitive random access method to produce results that are available in a shorter time than traditional methods. In this prospective study a total of 989 stool specimens were tested over a period of 16 months in parallel using two isothermal amplification assays, AmpliVue® (Quidel) and Illumigene® (Meridian) and the results compared to those from toxigenic culture. In addition all specimens were tested using a cytotoxic cell neutralisation assay (CCNA) and three different Real-time PCR targeting a C. difficile-specific 16S rDNA sequence or the toxin genes tcdA, tcdB/tcdB027 or cdtB. AmpliVue® was positive in 242 (24.5%) and Illumigene® in 228 (23.1%) specimens. 167 (16.9%) specimens were positive in toxigenic culture. Real-time-tcdA and -tcdB PCR was positive in 211 (21.3%) specimens, Real-time-cdtB PCR was positive in 101 (10.2%) specimens and C. difficile-PCR (16S rDNA) in 267 (27.0%) specimens. The respective sensitivity, specificity, positive predictive value and negative predictive value compared to toxigenic culture were 91, 89, 62 and 98% for AmpliVue® and 91, 91, 67 and 98% for Illumigene®.
Stojanov, M; Magalhaes, B; Terletsky, V; Basset, P; Prod'hom, G; Greub, G; Senn, L; Blanc, D S
Despite the development of novel typing methods based on whole genome sequencing, most laboratories still rely on classical molecular methods for outbreak investigation or surveillance. Reference methods for Clostridium difficile include ribotyping and pulsed-field gel electrophoresis, which are band-comparing methods often difficult to establish and which require reference strain collections. Here, we present the double locus sequence typing (DLST) scheme as a tool to analyse C. difficile isolates. Using a collection of clinical C. difficile isolates recovered during a 1-year period, we evaluated the performance of DLST and compared the results to multilocus sequence typing (MLST), a sequence-based method that has been used to study the structure of bacterial populations and highlight major clones. DLST had a higher discriminatory power compared to MLST (Simpson's index of diversity of 0.979 versus 0.965) and successfully identified all isolates of the study (100 % typeability). Previous studies showed that the discriminatory power of ribotyping was comparable to that of MLST; thus, DLST might be more discriminatory than ribotyping. DLST is easy to establish and provides several advantages, including absence of DNA extraction [polymerase chain reaction (PCR) is performed on colonies], no specific instrumentation, low cost and unambiguous definition of types. Moreover, the implementation of a DLST typing scheme on an Internet database, such as that previously done for Staphylococcus aureus and Pseudomonas aeruginosa ( http://www.dlst.org ), will allow users to easily obtain the DLST type by submitting directly sequencing files and will avoid problems associated with multiple databases.
Krutova, M; Kinross, P; Barbut, F; Hajdu, A; Wilcox, M H; Kuijper, E J
The increasing incidence of Clostridium difficile infections (CDI) in healthcare settings in Europe since 2003 has affected both patients and healthcare systems. The implementation of effective CDI surveillance is key to enable monitoring of the occurrence and spread of C. difficile in healthcare and the timely detection of outbreaks. The aim of this review is to provide a summary of key components of effective CDI surveillance and to provide some practical recommendations. We also summarize the recent and current national CDI surveillance activities, to illustrate strengths and weaknesses of CDI surveillance in Europe. For the definition of key components of CDI surveillance, we consulted the current European Society of Clinical Microbiology and Infectious Diseases (ESCMID) CDI-related guidance documents and the European Centre for Disease Prevention and Control (ECDC) protocol for CDI surveillance in acute care hospitals. To summarize the recent and current national CDI surveillance activities, we discussed international multicentre CDI surveillance studies performed in 2005-13. In 2017, we also performed a new survey of existing CDI surveillance systems in 33 European countries. Key components for CDI surveillance are appropriate case definitions of CDI, standardized CDI diagnostics, agreement on CDI case origin definition, and the presentation of CDI rates with well-defined numerators and denominators. Incorporation of microbiological data is required to provide information on prevailing PCR ribotypes and antimicrobial susceptibility to first-line CDI treatment drugs. In 2017, 20 European countries had a national CDI surveillance system and 21 countries participated in ECDC-coordinated CDI surveillance. Since 2014, the number of centres with capacity for C. difficile typing has increased to 35 reference or central laboratories in 26 European countries. Incidence rates of CDI, obtained from a standardized CDI surveillance system, can be used as an important
Balassiano, I T; Yates, E A; Domingues, R M C P; Ferreira, E O
Clostridium difficile-associated disease (CDAD) is caused by a spore-forming bacterium and can result in highly variable disease, ranging from mild diarrhoea to severe clinical manifestations. Infections are most commonly seen in hospital settings and are often associated with on-going antibiotic therapy. Incidences of CDAD have shown a sustained increase worldwide over the last ten years and a hypervirulent C. difficile strain, PCR ribotype 027/REA type BI/North American pulsed-field (NAP) type 1 (027/BI/NAP-1), has caused outbreaks in North America and Europe. In contrast, only a few reports of cases in Latin America have been published and the hypervirulent strain 027/BI/NAP-1 has, so far, only been reported in Costa Rica. The potential worldwide spread of this infection calls for epidemiological studies to characterize currently circulating strains and also highlights the need for increased awareness and vigilance among healthcare professionals in currently unaffected areas, such as Latin America. This review attempts to summarize reports of C. difficile infection worldwide, especially in Latin America, and aims to provide an introduction to the problems associated with this pathogen for those countries that might face outbreaks of epidemic strains of C. difficile for the first time in the near future.
Janezic, Sandra; Indra, Alexander; Rattei, Thomas; Weinmaier, Thomas; Rupnik, Maja
PCR-ribotyping, a typing method based on size variation in 16S-23S rRNA intergenic spacer region (ISR), has been used widely for molecular epidemiological investigations of C. difficile infections. In the present study, we describe the sequence diversity of ISRs from 43 C. difficile strains, representing different PCR-ribotypes and suggest homologous recombination as a possible mechanism driving the evolution of 16S-23S rRNA ISRs. ISRs of 45 different lengths (ranging from 185 bp to 564 bp) were found among 458 ISRs. All ISRs could be described with one of the 22 different structural groups defined by the presence or absence of different sequence modules; tRNAAla genes and different combinations of spacers of different lengths (33 bp, 53 bp or 20 bp) and 9 bp direct repeats separating the spacers. The ISR structural group, in most cases, coincided with the sequence length. ISRs that were of the same lengths had also very similar nucleotide sequence, suggesting that ISRs were not suitable for discriminating between different strains based only on the ISR sequence. Despite large variations in the length, the alignment of ISR sequences, based on the primary sequence and secondary structure information, revealed many conserved regions which were mainly involved in maturation of pre-rRNA. Phylogenetic analysis of the ISR alignment yielded strong evidence for intra- and inter-homologous recombination which could be one of the mechanisms driving the evolution of C. difficile 16S-23S ISRs. The modular structure of the ISR, the high sequence similarities of ISRs of the same sizes and the presence of homologous recombination also suggest that different copies of C. difficile 16S-23S rRNA ISR are evolving in concert.
Full Text Available PCR-ribotyping, a typing method based on size variation in 16S-23S rRNA intergenic spacer region (ISR, has been used widely for molecular epidemiological investigations of C. difficile infections. In the present study, we describe the sequence diversity of ISRs from 43 C. difficile strains, representing different PCR-ribotypes and suggest homologous recombination as a possible mechanism driving the evolution of 16S-23S rRNA ISRs. ISRs of 45 different lengths (ranging from 185 bp to 564 bp were found among 458 ISRs. All ISRs could be described with one of the 22 different structural groups defined by the presence or absence of different sequence modules; tRNAAla genes and different combinations of spacers of different lengths (33 bp, 53 bp or 20 bp and 9 bp direct repeats separating the spacers. The ISR structural group, in most cases, coincided with the sequence length. ISRs that were of the same lengths had also very similar nucleotide sequence, suggesting that ISRs were not suitable for discriminating between different strains based only on the ISR sequence. Despite large variations in the length, the alignment of ISR sequences, based on the primary sequence and secondary structure information, revealed many conserved regions which were mainly involved in maturation of pre-rRNA. Phylogenetic analysis of the ISR alignment yielded strong evidence for intra- and inter-homologous recombination which could be one of the mechanisms driving the evolution of C. difficile 16S-23S ISRs. The modular structure of the ISR, the high sequence similarities of ISRs of the same sizes and the presence of homologous recombination also suggest that different copies of C. difficile 16S-23S rRNA ISR are evolving in concert.
Grześkowiak, Łukasz; Zentek, Jürgen; Vahjen, Wilfried
A considerable fraction of the faecal microbiota is spore-forming. Molecular quantification of bacteria may be underestimated if preceded with nucleic acid extraction without special treatment to extract recalcitrant bacterial spores. The objective of this study was to improve the DNA extraction regarding the presence of Clostridium difficile spores in faecal swine specimens. Sow faeces were inoculated with spores of C. difficile (10(6) CFU), frozen at - 30 °C overnight and subjected to DNA extraction. As a preceding step to a standard DNA extraction method (QIAamp DNA stool Mini kit), different physical treatments such as microwave oven heating and repeated bead-beating techniques and a combination of both were applied and compared with each other by means of qPCR. Using a standard DNA extraction method only, C. difficile spores were quantified at 4.96 log copy number/200 mg of faeces. A repeated bead-beating at 6 m/s for 10 min followed by a standard DNA extraction resulted in 5.77 log copy number of spores in inoculated faeces. Heating in a microwave oven at 800 W for 1, 3, 5 and 10 min followed by a standard DNA extraction resulted in a gene quantification of up to 4.89 log copy number. A combination of both methods resulted in the bacterial gene quantity of 5.37 log copy number. Pre-treatment with repeated bead-beating led to the highest quantification of bacteria, and therefore it can be applied for more efficient DNA extraction from spores of C. difficile in faecal specimens.
Hart, J; Putsathit, P; Knight, D R; Sammels, L; Riley, T V; Keil, A
The increasing incidence of Clostridium difficile infection (CDI) in paediatric hospitalised populations, combined with the emergence of hypervirulent strains, community-acquired CDI and the need for prompt treatment and infection control, makes the rapid, accurate diagnosis of CDI crucial. We validated commonly used C. difficile diagnostic tests in a paediatric hospital population. From October 2011 to January 2012, 150 consecutive stools were collected from 75 patients at a tertiary paediatric hospital in Perth, Western Australia. Stools were tested using: C. Diff Quik Chek Complete, Illumigene C. difficile, GeneOhm Cdiff, cycloserine cefoxitin fructose agar (CCFA) culture, and cell culture cytotoxin neutralisation assay (CCNA). The reference standard was growth on CCFA or Cdiff Chromagar and PCR on isolates to detect tcdA, tcdB, cdtA, and cdtB. Isolates were PCR ribotyped. The prevalence of CDI was high (43 % of patients). Quik Chek Complete glutamate dehydrogenase (GDH) demonstrated a low negative predictive value (NPV) (93 %). Both CCNA and Quik Chek Complete toxin A/B had poor sensitivity (33 % and 29 % respectively). Molecular methods both had 89 % sensitivity. Algorithms using GDH + Illumigene or GeneOhm reduced the sensitivity to 85 % and 83 % respectively. Ribotype UK014/20 predominated. GDH NPV and GeneOhm and Illumigene sensitivities were reduced compared with adult studies. Quik Chek Complete and CCNA cannot reliably detect toxigenic CDI. A GDH first algorithm showed reduced sensitivity. In a high prevalence paediatric population, molecular methods alone are recommended over the use of GDH algorithm or culture and CCNA, as they demonstrate the best test performance characteristics.
Lancellotti,Marcelo; Pace,Fernanda de; Stehling,Eliana Guedes; Villares,Maria Cecília Barisson; Brocchi,Marcelo; Silveira,Wanderley Dias da
Forty-five Haemophilus influenzae strains isolated from patients were characterized based on biochemical characteristics. Their capsular types were determined by polymerase chain reaction (PCR); they were compared, using two molecular methods [ribotyping with a specific DNA probe amplified from the 16S rDNA region from H. influenzae and through restriction fragment length polymorphism (RLFP) of an amplified 16S DNA region]. The strains were better discriminated by the ribotyping technique tha...
Falcone, Marco; Venditti, Mario; Sanguinetti, Maurizio; Posteraro, Brunella
Patients with C. difficile infection (CDI) experience intestinal microflora changes that can promote the overgrowth and subsequent translocation of gut resident pathogens into the blood. Consistently, CDI due to PCR-ribotype 027 strain, severe or relapsing CDI, and treatment with high-dosage vancomycin are independent risk factors for candidemia. We review the role played by the gut microbiota during CDI and its treatment, as well as the clinical profile of CDI patients who are at risk of developing candidemia. Also, we discuss the management of these patients by focusing on pre-emptive strategies aimed at reducing the risk of candidemia, and on innovative anti-C. difficile therapies that may mitigate CDI-related effects such as the altered gut microbiota composition and prolonged intestinal mucosa damage. Expert commentary: A closer clinical and diagnostic monitoring of patients with CDI should help to limit the CDI-associated long-term consequences, including Candida infections, which worsen the outcome of hospitalized patients.
Khaki, Pejvak; Bhalla, Preena; Fayaz, Ahmad Mir; Moradi Bidhendi, Sohiela; Esmailzadeh, Majid; Sharma, Pawan
Control and preventive measures for gonococcal infections are based on precise epidemiological characteristics of N. gonorrhoeae isolates. In the present study the potential utility of opa-typing and ribotyping for molecular epidemiological study of consecutive gonococcal strains was determined. Sixty gonococcal isolates were subjected to ribotyping with two restriction enzymes, AvaII and HincII, and opa-typing with TaqI and HpaII for epidemiological characterization of gonococcal population. Ribotyping with AvaII yielded 6 ribotype patterns while twelve RFLP patterns were observed with HincII. Opa-typing of the 60 isolates revealed a total 54 opa-types, which 48 were unique and 6 formed clusters. Fifty-two opa-types were observed with TaqI-digested PCR product while opa-typing with HpaII demonstrated 54 opa-types. The opa-types from isolates that were epidemiologically unrelated were distinct, whereas those from the sexual contacts were identical. The results showed that opa-typing is highly useful for characterizing gonococcal strains from sexual contacts and has more discriminatory than ribotyping that could differentiate between gonococci of the same ribotype. The technique even with a single restriction enzyme has a high level of discrimination (99.9%) between epidemiologically unrelated isolates. In conclusion, the molecular methods such as opa-typing and ribotyping can be used for epidemiological characterization of gonococcal strains.
Khaki, Pejvak; Bhalla, Preena; Fayaz, Ahmad Mir; Moradi Bidhendi, Sohiela; Esmailzadeh, Majid; Sharma, Pawan
Control and preventive measures for gonococcal infections are based on precise epidemiological characteristics of N. gonorrhoeae isolates. In the present study the potential utility of opa-typing and ribotyping for molecular epidemiological study of consecutive gonococcal strains was determined. Sixty gonococcal isolates were subjected to ribotyping with two restriction enzymes, AvaII and HincII, and opa-typing with TaqI and HpaII for epidemiological characterization of gonococcal population. Ribotyping with AvaII yielded 6 ribotype patterns while twelve RFLP patterns were observed with HincII. Opa-typing of the 60 isolates revealed a total 54 opa-types, which 48 were unique and 6 formed clusters. Fifty-two opa-types were observed with TaqI-digested PCR product while opa-typing with HpaII demonstrated 54 opa-types. The opa-types from isolates that were epidemiologically unrelated were distinct, whereas those from the sexual contacts were identical. The results showed that opa-typing is highly useful for characterizing gonococcal strains from sexual contacts and has more discriminatory than ribotyping that could differentiate between gonococci of the same ribotype. The technique even with a single restriction enzyme has a high level of discrimination (99.9%) between epidemiologically unrelated isolates. In conclusion, the molecular methods such as opa-typing and ribotyping can be used for epidemiological characterization of gonococcal strains. PMID:20016674
Full Text Available Control and preventive measures for gonococcal infections are based on precise epidemiological characteristics of N. gonorrhoeae isolates. In the present study the potential utility of opa-typing and ribotyping for molecular epidemiological study of consecutive gonococcal strains was determined. Sixty gonococcal isolates were subjected to ribotyping with two restriction enzymes, AvaII and HincII, and opa-typing with TaqI and HpaII for epidemiological characterization of gonococcal population. Ribotyping with AvaII yielded 6 ribotype patterns while twelve RFLP patterns were observed with HincII. Opa-typing of the 60 isolates revealed a total 54 opa-types, which 48 were unique and 6 formed clusters. Fifty-two opa-types were observed with TaqI-digested PCR product while opa-typing with HpaII demonstrated 54 opa-types. The opa-types from isolates that were epidemiologically unrelated were distinct, whereas those from the sexual contacts were identical. The results showed that opa-typing is highly useful for characterizing gonococcal strains from sexual contacts and has more discriminatory than ribotyping that could differentiate between gonococci of the same ribotype. The technique even with a single restriction enzyme has a high level of discrimination (99.9% between epidemiologically unrelated isolates. In conclusion, the molecular methods such as opa-typing and ribotyping can be used for epidemiological characterization of gonococcal strains.
Pancholi, P; Kelly, C; Raczkowski, M; Balada-Llasat, J M
Clostridium difficile is the most important cause of nosocomial diarrhea. Several laboratory techniques are available to detect C. difficile toxins or the genes that encode them in fecal samples. We evaluated the Xpert C. difficile and Xpert C. difficile/Epi (Cepheid, CA) that detect the toxin B gene (tcdB) and tcdB, cdt, and a deletion in tcdC associated with the 027/NAP1/BI strain, respectively, by real-time PCR, and the Illumigene C. difficile (Meridian Bioscience, Inc.) that detects the toxin A gene (tcdA) by loop-mediated isothermal amplification in stool specimens. Toxigenic culture was used as the reference method for discrepant stool specimens. Two hundred prospective and fifty retrospective diarrheal stool specimens were tested simultaneously by the cell cytotoxin neutralization assay (CCNA) and the Xpert C. difficile, Xpert C. difficile/Epi, and Illumigene C. difficile assays. Of the 200 prospective stools tested, 10.5% (n = 23) were determined to be positive by CCNA, 17.5% (n = 35) were determined to be positive by Illumigene C. difficile, and 21.5% (n = 43) were determined to be positive by Xpert C. difficile and Xpert C. difficile/Epi. Of the 50 retrospective stools, previously determined to be positive by CCNA, 94% (n = 47) were determined to be positive by Illumigene C. difficile and 100% (n = 50) were determined to be positive by Xpert C. difficile and Xpert C. difficile/Epi. Of the 11 discrepant results (i.e., negative by Illumigene C. difficile but positive by Xpert C. difficile and Xpert C. difficile/Epi), all were determined to be positive by the toxigenic culture. A total of 21% of the isolates were presumptively identified by the Xpert C. difficile/Epi as the 027/NAP1/BI strain. The Xpert C. difficile and Xpert C. difficile/Epi assays were the most sensitive, rapid, and easy-to use assays for the detection of toxigenic C. difficile in stool specimens.
Curry, Scott R; Marsh, Jane W; Schlackman, Jessica L; Harrison, Lee H
The prevalence of Clostridium difficile in retail meat samples has varied widely. The food supply may be a source for C. difficile infections. A total of 102 ground meat and sausage samples from 3 grocers in Pittsburgh, PA, were cultured for C. difficile. Brand A pork sausages were resampled between May 2011 and January 2012. Two out of 102 (2.0%) meat products initially sampled were positive for C. difficile; both were pork sausage from brand A from the same processing facility (facility A). On subsequent sampling of brand A products, 10/19 samples from processing facility A and 1/10 samples from 3 other facilities were positive for C. difficile. The isolates recovered were inferred ribotype 078, comprising 6 genotypes. The prevalence of C. difficile in retail meat may not be as high as previously reported in North America. When contamination occurs, it may be related to events at processing facilities.
Kanerva, Mari; Ollgren, Jukka; Voipio, Tinna; Mentula, Silja; Lyytikäinen, Outi
Several antimicrobial agents and proton pump inhibitors (PPIs) have been identified as risk factors for Clostridium difficile infections (CDIs). Nationwide laboratory-based surveillance of CDIs in Finland since 2008 has shown variation in regional CDI rates. We evaluated whether regional differences in CDI rates were associated with antibacterial and PPI use. Data on mean annual incidence rates of CDIs during 2008-2011 in 21 healthcare districts (HDs) were obtained from the National Infectious Disease Register, consumption (median annual use) of antimicrobials and PPIs from the Finnish Medical Agency, availability of molecular diagnostics by a laboratory survey and data on ribotypes from the national reference laboratory. The association over the 4 years was measured by incidence rate ratio (IRR) and we performed both bivariate and multivariate analyses. During 2008-2011, PPI use increased 27% but fluoroquinolone use was stable. The level of fluoroquinolone use was strongly associated with the mean annual CDI incidence rate in different HDs over the 4-year period, but PPI use had less effect. The molecular diagnostics methodology and PCR ribotype 027 were not independently associated with CDI rate. The final multivariable model only included fluoroquinolone and PPI use; IRR for fluoroquinolones was 2.20 (95% confidence interval (CI), 1.32-3.67; p = 0.003). Fluoroquinolone use may play a role in regional differences in CDI rates. Although the use has not recently increased, regionally targeted antimicrobial stewardship campaigns promoting appropriate use of fluoroquinolones should still be encouraged since they may decrease the incidence of CDIs.
... toxin; Colitis - toxin; Pseudomembranous - toxin; Necrotizing colitis - toxin; C difficile - toxin ... be analyzed. There are several ways to detect C difficile toxin in the stool sample. Enzyme immunoassay ( ...
Full Text Available Measurement of both calprotectin and lactoferrin in faeces has successfully been used to discriminate between functional and inflammatory bowel conditions, but evidence is limited for Clostridium difficile infection (CDI. We prospectively recruited a cohort of 164 CDI cases and 52 controls with antibiotic-associated diarrhoea (AAD. Information on disease severity, duration of symptoms, 30-day mortality and 90-day recurrence as markers of complicated CDI were recorded. Specimens were subject to microbiological culture and PCR-ribotyping. Levels of faecal calprotectin (FC and lactoferrin (FL were measured by ELISA. Statistical analysis was conducted using percentile categorisation. ROC curve analysis was employed to determine optimal cut-off values. Both markers were highly correlated with each other (r2 = 0.74 and elevated in cases compared to controls (p0.85, although we observed a large amount of variability across both groups. The optimal case-control cut-off point was 148 mg/kg for FC and 8.1 ng/µl for FL. Median values for FL in CDI cases were significantly greater in patients suffering from severe disease compared to non-severe disease (104.6 vs. 40.1 ng/µl, p = 0.02, but were not significant for FC (969.3 vs. 512.7 mg/kg, p = 0.09. Neither marker was associated with 90-day recurrence, prolonged CDI symptoms, positive culture results and colonisation by ribotype 027. Both FC and FL distinguished between CDI cases and AAD controls. Although FL was associated with disease severity in CDI patients, this showed high inter-individual variability and was an isolated finding. Thus, FC and FL are unlikely to be useful as biomarkers of complicated CDI disease.
Full Text Available Abstract Background Clostridium difficile and methicillin-resistant Staphylococcus aureus are critical human pathogens and of increasing concern in food animals. Because of the apparent impact of age on prevalence of these organisms, studies of slaughter age pigs are important when considering the potential for contamination of food. This study evaluated C. difficile and MRSA shedding by slaughter age pigs from farms across Canada. Results Clostridium difficile was isolated from 30/436 (6.9% samples from 15/45 (33% farms. After adjusting for clustering at the herd level, the prevalence was 3.4%. Ribotype 078 (toxinotype V, North American Pulsotype 7 was the most common strain, accounting for 67% of isolates. MRSA was isolated from 21/460 (4.6% pigs from 5/46 (11% farms. The prevalence in pigs after adjusting for clustering at the herd level was 0.2%. Seven different spa types were identified, with 3 related spa types (t011, t034, new accounting for 16 (76% consistent with ST398 predominating. Both MRSA and C. difficile samples were collected from 45 farms. Both MRSA and C. difficile were detected on 2 (4.4%, with C. difficile only on 13 (29%, MRSA only on 3 (6.7% and neither on 27 (60%. Conclusions The prevalence of C. difficile and MRSA in slaughter age pigs was relatively low, particularly in comparison with studies involving younger pigs. The predominance of C. difficile ribotype 078 and MRSA ST398 was not surprising, but there was diversity in strain types and the majority of isolates of both organisms were strains that can be found in humans. While the prevalence of C. difficile and MRSA in slaughter age pigs was relatively low, there is clearly potential for contamination of meat from healthy pigs carrying this pathogen into slaughterhouses.
Schoster, Angelika; Arroyo, Luis Guillermo; Staempfli, Henry Rolf
BACKGROUND: Clostridium difficile and Clostridium perfringens are commonly associated with colitis in equids, but healthy carriers exist. Scarce information is available on the prevalence of Clostridium spp. in gastrointestinal compartments other than faeces in healthy horses, and it is unknown...... colon and rectum. When multiple compartments were positive in a single horse, two different C. difficile ribotypes were always present. Clostridium perfringens Type A (CPE, beta2 toxin gene negative) was recovered from the left ventral colon of one horse (0.74%, 1/135 samples). Agreement between faeces...... and overall C. difficile carrier status was good. CONCLUSIONS: Clostridium difficile can be found in different compartments of the gastrointestinal tract of healthy horses, and multiple strains can be present in an individual horse. The prevalence of C. perfringens in healthy adult hoses was low, consistent...
Jul 11, 2011 ... then in age group 31 to 40 years, 2.25% (2/89) CMV DNA were detected by PCR and 0% was recorded in age group of above 40 years. The overall prevalence of human cytomegalovirus (HCMV) infection in 16 ..... genome revisited: Comparison with the chimpanzee cytomegalovirus genome. J. Gen. Virol.
Brittany B. Lewis
Full Text Available Clostridium difficile is a spore-forming anaerobic bacterium that causes colitis in patients with disrupted colonic microbiota. While some individuals are asymptomatic C. difficile carriers, symptomatic disease ranges from mild diarrhea to potentially lethal toxic megacolon. The wide disease spectrum has been attributed to the infected host’s age, underlying diseases, immune status, and microbiome composition. However, strain-specific differences in C. difficile virulence have also been implicated in determining colitis severity. Because patients infected with C. difficile are unique in terms of medical history, microbiome composition, and immune competence, determining the relative contribution of C. difficile virulence to disease severity has been challenging, and conclusions regarding the virulence of specific strains have been inconsistent. To address this, we used a mouse model to test 33 clinical C. difficile strains isolated from patients with disease severities ranging from asymptomatic carriage to severe colitis, and we determined their relative in vivo virulence in genetically identical, antibiotic-pretreated mice. We found that murine infections with C. difficile clade 2 strains (including multilocus sequence type 1/ribotype 027 were associated with higher lethality and that C. difficile strains associated with greater human disease severity caused more severe disease in mice. While toxin production was not strongly correlated with in vivo colonic pathology, the ability of C. difficile strains to grow in the presence of secondary bile acids was associated with greater disease severity. Whole-genome sequencing and identification of core and accessory genes identified a subset of accessory genes that distinguish high-virulence from lower-virulence C. difficile strains.
Full Text Available Clostridium difficile has not been studied in detail in Asia, particularly Southeast Asia. We thus performed a prevalence study across four hospitals in Central Java province, Indonesia. Stool samples were collected from patients with diarrhoea and tested by enzyme immunoassay for glutamate dehydrogenase (GDH and toxin A/B (C DIFF QUIK CHEK COMPLETE, TechLab. Specimens were cultured and molecular typing was performed. In total, 340 samples were tested, of which 70 (20.6% were GDH positive, with toxin detected in 19 (5.6%. Toxigenic C. difficile was isolated from 37 specimens (10.9%, while a further 36 (10.6% nontoxigenic isolates were identified. The most common strain was ribotype 017 (24.3% of 74 isolates, followed by nontoxigenic types QX 224 (9.5%, and QX 238 and QX 108 (both 8.1%. The high prevalence of C. difficile highlights a need for ongoing surveillance of C. difficile infection in Indonesia.
Janet Y. Nale
Full Text Available Clostridium difficile infection (CDI is a major cause of infectious diarrhea. Conventional antibiotics are not universally effective for all ribotypes, and can trigger dysbiosis, resistance and recurrent infection. Thus, novel therapeutics are needed to replace and/or supplement the current antibiotics. Here, we describe the activity of an optimised 4-phage cocktail to clear cultures of a clinical ribotype 014/020 strain in fermentation vessels spiked with combined fecal slurries from four healthy volunteers. After 5 h, we observed ~6-log reductions in C. difficile abundance in the prophylaxis regimen and complete C. difficile eradication after 24 h following prophylactic or remedial regimens. Viability assays revealed that commensal enterococci, bifidobacteria, lactobacilli, total anaerobes, and enterobacteria were not affected by either regimens, but a ~2-log increase in the enterobacteria, lactobacilli, and total anaerobe abundance was seen in the phage-only-treated vessel compared to other treatments. The impact of the phage treatments on components of the microbiota was further assayed using metagenomic analysis. Together, our data supports the therapeutic application of our optimised phage cocktail to treat CDI. Also, the increase in specific commensals observed in the phage-treated control could prevent further colonisation of C. difficile, and thus provide protection from infection being able to establish.
... Gene Mutations Testing Cytomegalovirus (CMV) Tests D-dimer Dengue Fever Testing Des-gamma-carboxy prothrombin (DCP) DHEAS ... difficile. Medscape Today [On-line article from Pediatric Pharmacotherapy]. Available online at http://www.medscape.com/viewarticle/ ...
Koo, Hoonmo L; Van, John N; Zhao, Meina; Ye, Xunyan; Revell, Paula A; Jiang, Zhi-Dong; Grimes, Carolyn Z; Koo, Diana C; Lasco, Todd; Kozinetz, Claudia A; Garey, Kevin W; DuPont, Herbert L
To evaluate the accuracy of real-time polymerase chain reaction (PCR) for Clostridium difficile-associated disease (CDAD) detection, after hospital CDAD rates significantly increased following real-time PCR initiation for CDAD diagnosis. Hospital-wide surveillance study following examination of CDAD incidence density rates by interrupted time series design. Large university-based hospital. Hospitalized adult patients. CDAD rates were compared before and after real-time PCR implementation in a university hospital and in the absence of physician and infection control practice changes. After real-time PCR introduction, all hospitalized adult patients were screened for C. difficile by testing a fecal specimen by real-time PCR, toxin enzyme-linked immunosorbent assay, and toxigenic culture. CDAD hospital rates significantly increased after changing from cell culture cytotoxicity assay to a real-time PCR assay. One hundred ninety-nine hospitalized subjects were enrolled, and 101 fecal specimens were collected. C. difficile was detected in 18 subjects (18%), including 5 subjects (28%) with either definite or probable CDAD and 13 patients (72%) with asymptomatic C. difficile colonization. The majority of healthcare-associated diarrhea is not attributable to CDAD, and the prevalence of asymptomatic C. difficile colonization exceeds CDAD rates in healthcare facilities. PCR detection of asymptomatic C. difficile colonization among patients with non-CDAD diarrhea may be contributing to rising CDAD rates and a significant number of CDAD false positives. PCR may be useful for CDAD screening, but further study is needed to guide interpretation of PCR detection of C. difficile and the value of confirmatory tests. A gold standard CDAD diagnostic assay is needed.
Full Text Available Clostridium difficile (C. difficile is an important factor in the development of the gastrointestinal diseases because of irrational antibiotic prescription and antimicrobial resistance. In the past, this bacterium was introduced as an agent of the infection in the hospitals called "hospital acquired Clostridium difficile infection". This infection is a main cause of morbidity and mortality internationally. But changing in the epidemiology of the infection was observed in recent years. People not taking antibiotics as well as any contact with the clinical system were hospitalized due to the infection named "Community-Associated Clostridium difficile infection". Furthermore, the hypervirulent strains of C. difficile were identified outside of the health care facilities in different sources such as environment, animals and food products. Today the role of C. difficile has not been confirmed as a zoonotic agent or foodborne pathogen. Taking into account, it should be taken attention to the sensitive individuals such as pregnant women, elderly and children for the consumption of the contaminated food products with C. difficile spores and probable cause of the infection in these individuals. For this purpose, presentation of the guidelines or the prevention strategies for the transmission of bacteria in the society as well as the healthcare facilities is important. In this review study, the history, the risk factors of disease and the reports of infection in the healthcare facilities and outside of this environment in Iran were discussed. Finally, we supposed that based on the isolation of C. difficile with different genetic profile in Iran in comparison with international ribotypes, the existence of native strains leading to the infection in the community and the healthcare facilities is possible. This hypothesis shows the significance of regional differences in the epidemiology and microbiology of disease. In addition, according to the present
Wheeldon, L J; Worthington, T; Lambert, P A; Hilton, A C; Lowden, C J; Elliott, T S J
Persistent contamination of surfaces by spores of Clostridium difficile is a major factor influencing the spread of C. difficile-associated diarrhoea (CDAD) in the clinical setting. In recent years, the antimicrobial efficacy of metal surfaces has been investigated against microorganisms including methicillin-resistant Staphylococcus aureus. This study compared the survival of C. difficile on stainless steel, a metal contact surface widely used in hospitals, and copper surfaces. Antimicrobial efficacy was assessed using a carrier test method against dormant spores, germinating spores and vegetative cells of C. difficile (NCTC 11204 and ribotype 027) over a 3 h period in the presence and absence of organic matter. Copper metal eliminated all vegetative cells of C. difficile within 30 min, compared with stainless steel which demonstrated no antimicrobial activity (P or=2.5 log reduction (99.8% reduction) at 3 h. Organic material did not reduce the antimicrobial efficacy of the copper surface (P > 0.05). The use of copper surfaces within the clinical environment and application of a germination solution in infection control procedures may offer a novel way forward in eliminating C. difficile from contaminated surfaces and reducing CDAD.
Srwa J. Rashid
Full Text Available Bacteriophages (phages are increasingly being explored as therapeutic agents to combat bacterial diseases, including Clostridium difficile infections. Therapeutic phages need to be able to efficiently target and kill a wide range of clinically relevant strains. While many phage groups have yet to be investigated in detail, those with new and useful properties can potentially be identified when phages from newly studied geographies are characterised. Here, we report the isolation of C. difficile phages from soil samples from the north of Iraq. Two myoviruses, CDKM15 and CDKM9, were selected for detailed sequence analysis on the basis of their broad and potentially useful host range. CDKM9 infects 25/80 strains from 12/20 C. difficile ribotypes, and CDKM15 infects 20/80 strains from 9/20 ribotypes. Both phages can infect the clinically relevant ribotypes R027 and R001. Phylogenetic analysis based on whole genome sequencing revealed that the phages are genetically distinct from each other but closely related to other long-tailed myoviruses. A comparative genomic analysis revealed key differences in the genes predicted to encode for proteins involved in bacterial infection. Notably, CDKM15 carries a clustered regularly interspaced short palindromic repeat (CRISPR array with spacers that are homologous to sequences in the CDKM9 genome and of phages from diverse localities. The findings presented suggest a possible shared evolutionary past for these phages and provides evidence of their widespread dispersal.
Linda A Selvey
Full Text Available Identify risk factors for Clostridium difficile infection (CDI and assess CDI outcomes among Australian patients with a haematological malignancy.A retrospective cohort study involving all patients admitted to hospitals in Western Australia with a haematological malignancy from July 2011 to June 2012. Hospital admission data were linked with all hospital investigated CDI case data. Potential risk factors were assessed by logistic regression. The risk of death within 60 and 90 days of CDI was assessed by Cox Proportional Hazards regression.There were 2085 patients of whom 65 had at least one CDI. Twenty percent of CDI cases were either community-acquired, indeterminate source or had only single-day admissions in the 28 days prior to CDI. Using logistic regression, having acute lymphocytic leukaemia, neutropenia and having had bacterial pneumonia or another bacterial infection were associated with CDI. CDI was associated with an increased risk of death within 60 and 90 days post CDI, but only two deaths had CDI recorded as an antecedent factor. Ribotyping information was available for 33 of the 65 CDIs. There were 19 different ribotypes identified.Neutropenia was strongly associated with CDI. While having CDI is a risk factor for death, in many cases it may not be a direct contributor to death but may reflect patients having higher morbidity. A wide variety of C. difficile ribotypes were found and community-acquired infection may be under-estimated in these patients.
Eamonn P. Culligan
Full Text Available Clostridium difficile is a major cause of morbidity and mortality worldwide, causing over 400,000 infections and approximately 29,000 deaths in the United States alone each year. C. difficile is the most common cause of nosocomial diarrhoea in the developed world, and, in recent years, the emergence of hyper-virulent (mainly ribotypes 027 and 078, sometimes characterised by increased toxin production, epidemic strains and an increase in the number of community-acquired infections has caused further concern. Antibiotic therapy with metronidazole, vancomycin or fidaxomicin is the primary treatment for C. difficile infection (CDI. However, CDI is unique, in that, antibiotic use is also a major risk factor for acquiring CDI or recurrent CDI due to disruption of the normal gut microbiota. Therefore, there is an urgent need for alternative, non-antibiotic therapeutics to treat or prevent CDI. Here, we review a number of such potential treatments which have emerged from advances in the field of microbiome research.
Riedel, Thomas; Wetzel, Daniela; Hofmann, Julia Danielle; Plorin, Simon Paul Erich Otto; Dannheim, Henning; Berges, Mareike; Zimmermann, Ortrud; Bunk, Boyke; Schober, Isabel; Spröer, Cathrin; Liesegang, Heiko; Jahn, Dieter; Overmann, Jörg; Groß, Uwe; Neumann-Schaal, Meina
Clostridioides difficile (formerly Clostridium difficile) is a major nosocomial pathogen with an increasing number of community-acquired infections causing symptoms from mild diarrhea to life-threatening colitis. The pathogenicity of C. difficile is considered to be mainly associated with the production of genome-encoded toxins A and B. In addition, some strains also encode and express the binary toxin CDT. However; a large number of non-toxigenic C. difficile strains have been isolated from the human gut and the environment. In this study, we characterized the growth behavior, motility and fermentation product formation of 17 different C. difficile isolates comprising five different major genomic clades and five different toxin inventories in relation to the C. difficile model strains 630Δerm and R20291. Within 33 determined fermentation products, we identified two yet undescribed products (5-methylhexanoate and 4-(methylthio)-butanoate) of C. difficile. Our data revealed major differences in the fermentation products obtained after growth in a medium containing casamino acids and glucose as carbon and energy source. While the metabolism of branched chain amino acids remained comparable in all isolates, the aromatic amino acid uptake and metabolism and the central carbon metabolism-associated fermentation pathways varied strongly between the isolates. The patterns obtained followed neither the classification of the clades nor the ribotyping patterns nor the toxin distribution. As the toxin formation is strongly connected to the metabolism, our data allow an improved differentiation of C. difficile strains. The observed metabolic flexibility provides the optimal basis for the adaption in the course of infection and to changing conditions in different environments including the human gut. Copyright © 2017 Elsevier GmbH. All rights reserved.
Fiehn, N E; Bangsborg, J M; Colding, H
In the present study DNA restriction patterns and corresponding ribotypes of 17 subgingival small-sized spirochetes (1:2:1 and 2:4:2 isolates), 2 Treponema socranskii strains and two Treponema denticola strains were examined. Purified chromosomal DNA was digested by BamHI, HindIII, PstI and ClaI....
Fiehn, N E; Bangsborg, J M; Colding, H
In the present study DNA restriction patterns and corresponding ribotypes of 17 subgingival small-sized spirochetes (1:2:1 and 2:4:2 isolates), 2 Treponema socranskii strains and two Treponema denticola strains were examined. Purified chromosomal DNA was digested by BamHI, HindIII, PstI and Cla...
Mayer, Melinda J.; Narbad, Arjan; Gasson, Michael J.
Clostridium difficile infection is increasing in both frequency and severity, with the emergence of new highly virulent strains highlighting the need for more rapid and effective methods of control. Here, we show that bacteriophage endolysin can be used to inhibit and kill C. difficile. The genome sequence of a novel bacteriophage that is active against C. difficile was determined, and the bacteriophage endolysin gene was subcloned and expressed in Escherichia coli. The partially purified endolysin was active against 30 diverse strains of C. difficile, and importantly, this group included strains of the major epidemic ribotype 027 (B1/NAP1). In contrast, a range of commensal species that inhabit the gastrointestinal tract, including several representatives of the clostridium-like Firmicutes, were insensitive to the endolysin. This endolysin provides a platform for the generation of both therapeutic and detection systems to combat the C. difficile problem. To investigate a method for the protected delivery and production of the lysin in the gastrointestinal tract, we demonstrated the expression of active CD27L endolysin in the lactic acid bacterium Lactococcus lactis MG1363. PMID:18708505
Mayer, Melinda J; Narbad, Arjan; Gasson, Michael J
Clostridium difficile infection is increasing in both frequency and severity, with the emergence of new highly virulent strains highlighting the need for more rapid and effective methods of control. Here, we show that bacteriophage endolysin can be used to inhibit and kill C. difficile. The genome sequence of a novel bacteriophage that is active against C. difficile was determined, and the bacteriophage endolysin gene was subcloned and expressed in Escherichia coli. The partially purified endolysin was active against 30 diverse strains of C. difficile, and importantly, this group included strains of the major epidemic ribotype 027 (B1/NAP1). In contrast, a range of commensal species that inhabit the gastrointestinal tract, including several representatives of the clostridium-like Firmicutes, were insensitive to the endolysin. This endolysin provides a platform for the generation of both therapeutic and detection systems to combat the C. difficile problem. To investigate a method for the protected delivery and production of the lysin in the gastrointestinal tract, we demonstrated the expression of active CD27L endolysin in the lactic acid bacterium Lactococcus lactis MG1363.
Xu, Changyun; Salsali, Hamidreza; Weese, Scott; Warriner, Keith
There has been an increase in community-associated Clostridium difficile infections with biosolids derived from wastewater treatment being identified as one potential source. The current study evaluated the efficacy of thermophilic digestion in decreasing levels of C. difficile ribotype 078 associated with sewage sludge. Five isolates of C. difficile 078 were introduced (final density of 5 log CFU/g) into digested sludge and subjected to anaerobic digestion at mesophilic (36 or 42 °C) or thermophilic (55 °C) temperatures for up to 60 days. It was found that mesophilic digestion at 36 °C did not result in a significant reduction in C. difficile spore levels. In contrast, thermophilic sludge digestion reduced endospore levels at a rate of 0.19-2.68 log CFU/day, depending on the strain tested. The mechanism of lethality was indirect - by stimulating germination then inactivating the resultant vegetative cells. Acidification of sludge by adding acetic acid (6 g/L) inhibited the germination of spores regardless of the sludge digestion temperature. In conclusion, thermophilic digestion can be applied to reduce C. difficile in biosolids, thereby reducing the environmental burden of the enteric pathogen.
This podcast is based on the March 2012 CDC Vital Signs report. C. difficile is a germ that causes diarrhea linked to 14,000 deaths in the US each year. This podcast helps health care professionals learn how to prevent C. difficile infections. Created: 3/6/2012 by Centers for Disease Control and Prevention (CDC). Date Released: 3/6/2012.
Hussain, Isfaqul; Borah, P; Sharma, R K; Rajkhowa, S; Rupnik, M; Saikia, D P; Hasin, D; Hussain, Iftikar; Deka, N K; Barkalita, L M; Nishikawa, Y; Ramamurthy, T
A total of 1034 samples were collected from different sources and C. difficile was isolated from 18 (9.04%) of 199 human, 9 (4.89%) of 184 cattle, 29 (12.44%) of 233 pig, and from 23 (13.94%) of 165 poultry samples. Variations were observed on the rate of isolation according to age and clinical conditions (diarrhoea). None of the samples from cow, sheep, goat, local chicken, and wild animals yielded any C. difficile. Out of those isolates, 8, 2, 19 and 6 isolates from human, cattle, pig and poultry, respectively were toxigenic. The toxigenic isolates carried both tcdA, and tcdB (A + B + ) and most of the human and the pig isolates were also positive for binary toxin genes (cdtA and cdtB). The A + B + isolates belonged to three different toxinotypes (0, VI and XXXIII). Human and pig A + B + isolates belonged to three (045, 126 and ACD 019) and four (046, 087, 126 and ACD 011) different ribotypes, respectively and the ribotypes of two cattle isolates were 014 and ACD 010. Six A + B + avian isolates belonged to six different ribotypes (014, 087, SLO 134, SLO 160, ACD 012, ACD 014). The non-toxigenic isolates from human, cattle, pig and poultry were grouped into 7, 4, 4 and 7 different ribotypes, respectively. PFGE analysis could not differentiate similar ribotypes/toxinotypes of toxigenic isolates. All the toxigenic isolates showed cytopathic effect on Vero and Hela cell monolayers at 1:100 dilutions of cell-free culture supernatants within 18-20 h of inoculation. Copyright © 2016 Elsevier Ltd. All rights reserved.
Rasmussen, S. R.; Aarestrup, Frank Møller; Jensen, N. E.
A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting in the identificat......A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting...... of resistance to antibiotics because strains isolated from pigs with meningitis were resistant to sulfamethazoxazole and strains isolated from pigs with pneumonia, endocarditis, pericarditis, or septicemia were resist-ant to tetracycline....... ribotypes were almost exclusively isolated from pigs with meningitis, while strains of the other dominant ribotype were never associated with meningitis. This second ribotype was isolated only from pigs with pneumonia, endocarditis, pericarditis, or septicemia. Cluster analysis revealed that strains...
Full Text Available Wastewater is a potential environmental source of Clostridium difficile, although a direct link with community-acquired C. difficile infection (CA-CDI in humans has not yet been established. The present study was performed to determine the occurrence of C. difficile in two types of wastewater treatment plants (WWTPs in Isfahan, Iran. A total of 95 samples were taken from a conventional activated sludge treatment plant and a waste stabilization ponds system, and analyzed for the presence of C. difficile. C. difficile was found in 13.6% (3/22 of digested sludge samples. However, no C. difficile was detected in inlet and outlet samples or in raw sludge of activated sludge. C. difficile was also detected in 5% (2/40 of the samples from waste stabilization ponds. Polymerase chain reaction (PCR analysis showed that all strains of C. difficile detected were toxigenic (tcdB gene positive. This study shows that C. difficile was present in WWTPs, which might constitute a potential source of community-acquired C. difficile infection.
Magistrali, Chiara Francesca; Maresca, Carmen; Cucco, Lucilla; Bano, Luca; Drigo, Ilenia; Filippini, Giovanni; Dettori, Annalisa; Broccatelli, Sayra; Pezzotti, Giovanni
The aim of this study is to describe the prevalence and risk factors of Clostridium difficile shedding in six farms belonging to two companies in Northern Italy. Four hundred and twenty veal calves, randomly selected and individually identified, were sampled three times: at 0-16, 90-120, and 150 days after introduction. C. difficile was isolated at least once from 87 out of the 420 calves (20.7%). The prevalence of shedding was 20.24% at the first sampling and dropped to 0.72% at the second sampling. None of the samples obtained at 150 days tested positive. Sampling of cecal contents and carcass swabs at slaughter was stratified according to the herd of origin of the animals. C. difficile was never isolated at slaughter, excluding a prevalence higher than 3.5% on the basis of previous investigations. Therefore, in this work, the veal calf could not be confirmed as a potential source of C. difficile for the consumer. Eight different ribotypes (RT) have been described, but the vast majority of the isolates (87.8%) belonged to three ribotypes only: RT-078, RT-012 and RT-126, which are also among the most common of the ribotypes detected in humans in Europe. Most isolates, and all the RT-078 isolates, harbored genes coding for toxins A and B, the binary toxin, and showed a deletion in the gene encoding toxin C, suggesting that the veal calf was a reservoir for epidemic hyper-virulent strains. A correlation between age and shedding was found: the odds ratio (OR) ranged from 2.79 for 36-45 days of age to 4.57 for 13-28 days of age. The presence of diarrhea at first sampling was significantly associated with the recovery of C. difficile in feces (OR 3.26). A correlation was found between the administration of antimicrobials and shedding: an increased risk was shown when the number of antimicrobials used was higher than 4 (OR 4.02) or 5-6 (OR 5.83) or when polymyxin E or beta-lactams were administered. Copyright © 2015 Elsevier Ltd. All rights reserved.
Madsen, Lone; Dalsgaard, Inger
Ribotyping and plasmid profiling were carried out on 299 Danish Flavobacterium psychrophilum isolates from farmed rainbow trout, Oncorhynchus mykiss (Walbaum). The isolates had been characterized biochemically and serologically in another study. The isolates were very homogeneous, 254 isolates had...... the same ribotype A (restriction enzyme EcoRI) and 284 isolates harboured one 3.3 kb plasmid. Seventy-five per cent of the F. psychrophilum isolates had ribotype A, one 3.3 kb plasmid and belonged to either serotype Th or Fd. Virulence studies with representatives of the dominant groups classified...... such isolates as virulent, and an extra small or large plasmid did not change the virulence level. A relationship between the serotypes Fd and Th, certain ribotypes, and virulence was found. The isolates belonging to serotype Fp(T) and to ribotype B were less virulent. Only a few isolates with other ribotypes...
Fussing, V.; Barfod, Kristen; Nielsen, R.
was indicated in one of two cases. In many cases findings of predominant ribotypes made interpretations of suspected routes of transmission difficult. The relationship of strains based on ribotypes was calculated using Dices coefficient and clustered by UPGMA. HindIII ribotypes of serotype 2 strains were...... was isolated from all SPF herds included in this study, except one, emphasizing the high prevalence of this serotype in Denmark. By ribotyping, airborne transmission was indicated in five of 12 cases, transmission via pig transporting vehicle was indicated in six of nine cases, and transmission via trading...
... TeensRead MoreBMI Calculator Acute BronchitisHigh Blood PressureBursitis of the HipHigh CholesterolExercise-induced UrticariaMicroscopic HematuriaKidney CystsDe Quervain’s Tenosynovitis Home Diseases and Conditions Clostridium difficile (C. diff.) ...
... Symptoms include Watery diarrhea (at least three bowel movements per day for two or more days) Fever Loss of appetite Nausea Abdominal pain or tenderness C. difficile is more common in people who need to take antibiotics for a long period of time.The elderly also have a higher risk of getting it. ...
Francis D. LaBarbera
Full Text Available Background: Clostridium difficile infection (CDI is a growing problem in the community and hospital setting. Its incidence has been on the rise over the past two decades, and it is quickly becoming a major concern for the health care system. High rate of recurrence is one of the major hurdles in the successful treatment of C. difficile infection. There have been few studies that have looked at patterns of recurrence. The studies currently available have shown a number of risk factors associated with C. difficile recurrence (CDR; however, there is little consensus on the impact of most of the identified risk factors. Methods: Our study was a retrospective chart review of 198 patients diagnosed with CDI via Polymerase Chain Reaction (PCR from February 2009 to Jun 2013. In our study, we decided to use a machine learning algorithm called the Random Forest (RF to analyze all of the factors proposed to be associated with CDR. This model is capable of making predictions based on a large number of variables, and has outperformed numerous other models and statistical methods. Results: We came up with a model that was able to accurately predict the CDR with a sensitivity of 83.3%, specificity of 63.1%, and area under curve of 82.6%. Like other similar studies that have used the RF model, we also had very impressive results. Conclusions: We hope that in the future, machine learning algorithms, such as the RF, will see a wider application.
Bandelj, P; Golob, M; Ocepek, M; Zdovc, I; Vengust, M
A significant risk factor for developing Clostridium difficile infection (CDI) in humans and animals is associated with the antimicrobial use. It has often been hypothesized that farm animals could be the source for human infection with Clostridium difficile (CD). In the European Union, family-run dairy farms are the predominant farming model, which are more interlinked within the community compared to large-scale intensive dairy or beef farms. Therefore, it is important to investigate antimicrobial susceptibility patterns of CD in such environment. A total of 159 CD isolates from 20 family dairy farms were tested with a customized broth microdilution plate for their antimicrobial resistance. Seventeen antimicrobials were selected (amoxicillin, ceftriaxone, clindamycin, daptomycin, erythromycin, fusidic acid, imipenem, levofloxacin, linezolid, metronidazole, moxifloxacin, oxacillin, rifampicin, tetracycline, tigecycline, trimethoprim/sulfamethoxazole and vancomycin), which are commonly used for treatment of CDI in veterinary and human medicine, or were previously applied in CD epidemiological studies. Antimicrobials, which are used for treatment of CDI in humans (metronidazole, vancomycin, fusidic acid, tigecycline, linezolid) inhibited CD growth in vitro. Most CD isolates were resistant to erythromycin (93.1%), daptomycin (69.2%) and clindamycin (46.5%). High multiple-resistance was found in CD ribotype 012 (n = 5, 100%), some CD SLO 060 (n = 4, 25%) and one CD 033 (n = 1, 1.1%). High multiple-resistance in this study was linked with CD ribotypes and not with the origin of CD. The low prevalence of these ribotypes (6.3%; 10/159) indicates that family-run dairy farms are an unlikely source of CD with multiple-resistance to antimicrobials. © 2016 Blackwell Verlag GmbH.
Shelley A Lyon
Full Text Available Clostridium difficile is a global health burden and the leading cause of antibiotic-associated diarrhoea worldwide, causing severe gastrointestinal disease and death. Three well characterised toxins are encoded by this bacterium in two genetic loci, specifically, TcdB (toxin B and TcdA (toxin A in the Pathogenicity Locus (PaLoc and binary toxin (CDT in the genomically distinct CDT locus (CdtLoc. Toxin production is controlled by regulators specific to each locus. The orphan response regulator, CdtR, encoded within the CdtLoc, up-regulates CDT production. Until now there has been no suggestion that CdtR influences TcdA and TcdB production since it is not carried by all PaLoc-containing strains and CdtLoc is not linked genetically to PaLoc. Here we show that, in addition to CDT, CdtR regulates TcdA and TcdB production but that this effect is strain dependent. Of clinical relevance, CdtR increased the production of TcdA, TcdB and CDT in two epidemic ribotype 027 human strains, modulating their virulence in a mouse infection model. Strains traditionally from animal lineages, notably ribotype 078 strains, are increasingly being isolated from humans and their genetic and phenotypic analysis is critical for future studies on this important pathogen. Here we show that CdtR-mediated toxin regulation did not occur in other strain backgrounds, including a ribotype 078 animal strain. The finding that toxin gene regulation is strain dependent highlights the regulatory diversity between C. difficile isolates and the importance of studying virulence regulation in diverse lineages and clinically relevant strains. Our work provides the first evidence that TcdA, TcdB and CDT production is linked by a common regulatory mechanism and that CdtR may act as a global regulator of virulence in epidemic 027 strains.
High prevalence of subclass-specific binding and neutralizing antibodies against Clostridium difficile toxins in adult cystic fibrosis sera: possible mode of immunoprotection against symptomatic C. difficile infection
Full Text Available Tanya M Monaghan,1 Ola H Negm,2,3 Brendon MacKenzie,4 Mohamed R Hamed,2,3 Clifford C Shone,5 David P Humphreys,4 K Ravi Acharya,6 Mark H Wilcox7 1Nottingham Digestive Diseases Centre, NIHR Nottingham Digestive Diseases Biomedical Research Unit, School of Medicine, University of Nottingham, Nottingham, 2Breast Surgery Group, Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, Queen’s Medical Centre, University of Nottingham, Nottingham, UK; 3Medical Microbiology and Immunology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt; 4Antibody Biology, UCB-New Medicines, UCB Celltech, Slough, UK; 5Toxins Group, National Infection Service, Public Health England, Salisbury, UK; 6Department of Biology and Biochemistry, University of Bath, Bath, UK; 7Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK Objectives: Despite multiple risk factors and a high rate of colonization for Clostridium difficile, the occurrence of C. difficile infection in patients with cystic fibrosis is rare. The aim of this study was to compare the prevalence of binding C. difficile toxin-specific immunoglobulin (IgA, IgG and anti-toxin neutralizing antibodies in the sera of adults with cystic fibrosis, symptomatic C. difficile infection (without cystic fibrosis and healthy controls. Methods: Subclass-specific IgA and IgG responses to highly purified whole C. difficile toxins A and B (toxinotype 0, strain VPI 10463, ribotype 087, toxin B from a C. difficile toxin-B-only expressing strain (CCUG 20309 and precursor form of B fragment of binary toxin, pCDTb, were determined by protein microarray. Neutralizing antibodies to C. difficile toxins A and B were evaluated using a Caco-2 cell-based neutralization assay. Results: Serum IgA anti-toxin A and B levels and neutralizing antibodies against toxin A were significantly higher in adult cystic fibrosis patients (n=16 compared with healthy controls (n=17 and
Eman N. Abu-Khader
Full Text Available Clostridium difficile is commonly found in the intestine of infants without causing any disease. This study investigated the most important epidemiological features of C. difficile strains colonizing intestine of Jordanian infants. A total of 287 fecal samples were collected from infants admitted to the Jordan University Hospital (JUH over the period of 2015. Samples were cultured for C. difficile and their growth was identified using microbiological culture and PCR. The overall C. difficile colonization rate among hospitalized and nonhospitalized infants was 37/287 (12.9%. Neonates were less colonized than other infants (8.7% verses 19.5%. Colonization of the infants with C. difficile toxigenic strains (TcdA and TcdB was observed in 54% of the isolates, whereas those colonized with nontoxigenic strains were 46% and only one isolate was positive for binary toxin. Breast feeding of infants is a significant factor associated with decreased colonization with C. difficile. All C. difficile strains were susceptible to vancomycin and metronidazole, while high resistance rate to ciprofloxacin (78.4% and less resistance rate to erythromycin (29.7% were detected among the isolates. The results showed that 40.5% of the isolates carried mutated gyrA and gyrB genes which have cross-resistance to ciprofloxacin and moxifloxacin. This study represents useful epidemiological features about C. difficile colonizing intestine of infants living in a developing country.
Full Text Available Clostridium difficile is a nosocomial pathogen that causes a serious toxin-mediated enteric disease in humans. Reducing C. difficile toxin production could significantly minimize its pathogenicity and improve disease outcomes in humans. This study investigated the efficacy of two, food-grade, plant-derived compounds, namely trans-cinnamaldehyde (TC and carvacrol (CR in reducing C. difficile toxin production and cytotoxicity in vitro. Three hypervirulent C. difficile isolates were grown with or without the sub-inhibitory concentrations of TC or CR, and the culture supernatant and the bacterial pellet were collected for total toxin quantitation, Vero cell cytotoxicity assay and RT-qPCR analysis of toxin-encoding genes. The effect of CR and TC on a codY mutant and wild type C. difficile was also investigated. Carvacrol and TC substantially reduced C. difficile toxin production and cytotoxicity on Vero cells. The plant compounds also significantly down-regulated toxin production genes. Carvacrol and TC did not inhibit toxin production in the codY mutant of C. difficile, suggesting a potential codY-mediated anti-toxigenic mechanism of the plant compounds. The antitoxigenic concentrations of CR and TC did not inhibit the growth of beneficial gut bacteria. Our results suggest that CR and TC could potentially be used to control C. difficile, and warrant future studies in vivo.
Katherine Rose Hargreaves
Full Text Available Phages that infect Clostridium difficile were first isolated for typing purposes in the 1980s, but their use was short lived. However, the rise of C. difficile epidemics over the last decade has triggered a resurgence of interest in using phages to combat this pathogen. Phage therapy is an attractive treatment option for C. difficile infection, however developing suitable phages is challenging. In this review we summarise the difficulties faced by researchers in this field, and we discuss the solutions and strategies used for the development of C. difficile phages for use as novel therapeutics.Epidemiological data has highlighted the diversity and distribution of C. difficile, and shown that novel strains continue to emerge in clinical settings. In parallel with epidemiological studies, advances in molecular biology have bolstered our understanding of C. difficile biology, and our knowledge of phage-host interactions in other bacterial species. These three fields of biology have therefore paved the way for future work on C. difficile phages to progress and develop. Benefits of using C. difficile phages as therapeutic agents include the fact that they have highly specific interactions with their bacterial hosts. Studies also show that they can reduce bacterial numbers in both in vitro and in vivo systems. Genetic analysis has revealed the genomic diversity among these phages and provided an insight into their taxonomy and evolution.No strictly virulent C. difficile phages have been reported and this contributes to the difficulties with their therapeutic exploitation. Although treatment approaches using the phage-encoded endolysin protein have been explored, the benefits of using whole-phages are such that they remain a major research focus. Whilst we don’t envisage working with C. difficile phages will be problem free, sufficient study should inform future strategies to facilitate their development to combat this problematic pathogen.
Michael S M Brouwer
Full Text Available Clostridium difficile is the leading cause of hospital-associated diarrhoea in the US and Europe. Recently the incidence of C. difficile-associated disease has risen dramatically and concomitantly with the emergence of 'hypervirulent' strains associated with more severe disease and increased mortality. C. difficile contains numerous mobile genetic elements, resulting in the potential for a highly plastic genome. In the first sequenced strain, 630, there is one proven conjugative transposon (CTn, Tn5397, and six putative CTns (CTn1, CTn2 and CTn4-7, of which, CTn4 and CTn5 were capable of excision. In the second sequenced strain, R20291, two further CTns were described.CTn1, CTn2 CTn4, CTn5 and CTn7 were shown to excise from the genome of strain 630 and transfer to strain CD37. A putative CTn from R20291, misleadingly termed a phage island previously, was shown to excise and to contain three putative mobilisable transposons, one of which was capable of excision. In silico probing of C. difficile genome sequences with recombinase gene fragments identified new putative conjugative and mobilisable transposons related to the elements in strains 630 and R20291. CTn5-like elements were described occupying different insertion sites in different strains, CTn1-like elements that have lost the ability to excise in some ribotype 027 strains were described and one strain was shown to contain CTn5-like and CTn7-like elements arranged in tandem. Additionally, using bioinformatics, we updated previous gene annotations and predicted novel functions for the accessory gene products on these new elements.The genomes of the C. difficile strains examined contain highly related CTns suggesting recent horizontal gene transfer. Several elements were capable of excision and conjugative transfer. The presence of antibiotic resistance genes and genes predicted to promote adaptation to the intestinal environment suggests that CTns play a role in the interaction of C
Mullany, Peter; Roberts, Adam P
.... difficile research to describe the recently developed methods for studying the organism. These range from methods for isolation of the organism, molecular typing, genomics, genetic manipulation, and the use of animal models...
Bennekov, T; Colding, H; Ojeniyi, B
Forty Pseudomonas aeruginosa strains, previously characterized by pulsed-field gel electrophoresis, were ribotyped with EcoRI, BamHI, ClaI, and PvuII. Ribotyping with PvuII proved to be as discriminatory as pulsed-field gel electrophoresis with XbaI or DraI while EcoRI and BamHI were not. ClaI co...
González, Ana J.; Landeras, Elena; Mendoza, M. Carmen
Ribotyping was evaluated as a method to differentiate between Pseudomonas syringae pv. phaseolicola and pv. syringae strains causing bacterial brown spot and halo blight diseases in Phaseolus vulgaris L. Ribotyping, with restriction enzymes BglI and SalI and using the Escherichia coli rrnB operon as the probe, differentiated 11 and 14 ribotypes, respectively, and a combination of data from both procedures yielded 19 combined ribotypes. Cluster analysis of the combined ribotypes differentiated the pathovars phaseolicola and syringae, as well as different clonal lineages within these pathovars. The potential of ribotyping to screen for correlations between lineages and factors such as geographical region and/or bean varieties is also reported. PMID:10653764
Full Text Available Abstract Background Here we describe a cluster of hospital-acquired Clostridium difficile infections (CDI among 26 patients with osteoarticular infections. The aim of the study was to define the source of C. difficile and to evaluate the impact of general infection control measures and antibiotic stewardship on the incidence of CDI. Methods Epidemiological analysis included typing of C. difficile strains and analysis of possible patient to patient transmission. Infection control measures comprised strict isolation of CDI patients, additional hand washings, and intensified environmental cleaning with sporicidal disinfection. In addition an antibiotic stewardship program was implemented in order to prevent the use of CDI high risk antimicrobials such as fluoroquinolones, clindamycin, and cephalosporins. Results The majority of CDI (n = 15 were caused by C. difficile ribotype 027 (RT027. Most RT027 isolates (n = 9 showed high minimal inhibitory concentrations (MIC for levofloxacin, clindamycin, and remarkably to rifampicin, which were all used for the treatment of osteoarticular infections. Epidemiological analysis, however, revealed no closer genetic relationship among the majority of RT027 isolates. The incidence of CDI was reduced only when a significant reduction in the use of fluoroquinolones (p = 0.006, third generation cephalosporins (p = 0.015, and clindamycin (p = 0.001 was achieved after implementation of an intensified antibiotic stewardship program which included a systematic review of all antibiotic prescriptions. Conclusion The successful reduction of the CDI incidence demonstrates the importance of antibiotic stewardship programs focused on patients treated for osteoarticular infections.
Brygge, K; Sørensen, C H; Colding, H
ribotype in the nasopharynx at the same time. The vast majority of the nasopharyngeal M. catarrhalis cultures were beta-lactamase positive. One child had both a HAPA ribotype, beta-lactamase-negative strain in the nasopharyngeal secretions, and HAPA ribotype, beta-lactamase-positive strains at the entrance...... of the eustachian tube, the nasopharyngeal tonsils, the folds of the nasopharyngeal tonsils and the oropharynx. All except one of the M. catarrhalis strains cultured from middle ear exudates were beta-lactamase positive....
Over the last years major advances have been made in the field of C. difficile research. Despite the continuous progress of research in C. difficile epidemiology and molecular biology. This thesis shows that the development of molecular based techniques in detecetion and typing of C. difficile could
Este podcast se basa en la ediciÃ³n de marzo del 2012 del informe Vital Signs de los CDC. La Clostridium difficile es una bacteria que causa diarrea y estÃ¡ asociada a 14,000 muertes anuales en los Estados Unidos. Este podcast ayuda a los profesionales de la salud a saber cÃ³mo prevenir las infecciones por C. difficile. Created: 3/6/2012 by Centers for Disease Control and Prevention (CDC). Date Released: 3/6/2012.
Falces-Romero, Iker; Troyano-Hernáez, Paloma; García-Bujalance, Silvia; Baquero-Artigao, Fernando; Mellado-Peña, María José; García-Rodríguez, Julio
Our main objective was a revision of clinical, microbiological and epidemiological results of Clostridium difficile-associated infection in paediatric patients (2010-2015). We compared the diagnoses performed by detection of toxins in feces and those performed by real-time PCR. This retrospective study included 82 paediatric patients. Detection of toxigenic C. difficile was performed sequentially, in diarrheal feces and under clinical request. A total of 39% of the patients were attended at Haematology-oncology Unit and >50% of them had previously received cephalosporins. Fever associated with diarrhea was more frequent in the group of toxin detection, whereas not receiving specific antibiotic treatment was more frequent in the group of positive PCR, without statistically significant differences. We highlight the presence of C. difficile infection in children under 2years old. A diagnostic testing in selected paediatric patients would be advisable when there is clinical suspicion of infection. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.
Moacyr Silva Júnior
Full Text Available Clostridium difficile is the main cause of nosocomial diarrhea. Diarrhea associated with C. difficile has increased incidence, morbidity, and mortality in the last few years. The major related risk factors include use of antibiotics, elderly patients and prolonged hospital stay. Many patients receive combinations of antibiotics or multiple antibiotics, which represents the main risk to develop diarrhea associated to C. difficile or its recurrence. Therefore, interventions to improve antibiotic prescribing, as well as compliance with infection control measures can reduce hospital-acquired C. difficile infections. This review addresses the epidemiological changes in C. difficile disease and its treatment.
Bailey, J S; Fedorka-Cray, P J; Stern, N J; Craven, S E; Cox, N A; Cosby, D E
The subtyping and identification of bacterial pathogens throughout food processing and production chains is useful to the new hazard analysis critical control point-based food safety plans. Traditional manual serotyping remains the primary means of subtyping Salmonella isolates. Molecular biology techniques, however, offer the promise of more rapid and sensitive subtyping of Salmonella. This study evaluates the potential of restriction enzyme PvuII, followed by probing with the rRNA operon from Escherichia coli, to generate serotype-specific DNA fingerprints. A total of 32 identified serotypes were found with an overall agreement in 208 of the 259 (80%) isolates tested between U.S. Department of Agriculture serotype identification and riboprint serotype identification. Many of the isolates that did not correlate were serotype identified as Salmonella Montevideo, which indicates that for this serotype, there are multiple ribotypes. When Salmonella Montevideo isolates were not included, the ribotype identification agreed with serotyping in 207 of the 231 (90%) isolates. The primary outcome of any ribotyping procedure is to give distinct ribotype patterns. This extensive poultry epidemiological study demonstrates that, in addition to ribotype patterns, the identification of isolates to known serotypes provides the investigator with additional information that can be more useful than traditional epidemiology and isolate identification studies.
Kachrimanidou, Melina; Tegou, Zoi; Chasampalioti, Maria; Arvaniti, Kostoula; Protonotariou, Efthymia; Skoura, Lemonia
Clostridium difficile infection (CDI) is a major cause of health care-associated diarrhea. The aim of the present study was to evaluate a two-step approach for the diagnosis of CDI. The two-step procedure consisted of GDH-toxin A/B EIA (Enzyme immunoassay targeting enterotoxin A and Cytotoxin B), followed by PCR detecting toxigenic C. difficile. Results indicate that EIAs provide a rapid screening assay for the laboratory diagnosis of CDI but, in GDH-positive and toxins-negative samples, EIA should be always followed by PCR to distinguish toxigenic vs nontoxigenic strains. GDH-toxin A/B EIA-rapid test has high specificity but low sensitivity to detect CDI. The implementation of a two-step procedure significantly increases the diagnostic accuracy to detect CDI and provides a toxigenic type characterization of C. difficile isolates. Copyright © 2017 Elsevier B.V. All rights reserved.
Shaughnessy, Megan K; Bobr, Aleh; Kuskowski, Michael A; Johnston, Brian D; Sadowsky, Michael J; Khoruts, Alexander; Johnson, James R
Recurrent Clostridium difficile infection (R-CDI) is common and difficult to treat, potentially necessitating fecal microbiota transplantation (FMT). Although C. difficilespores persist in the hospital environment and cause infection, little is known about their potential presence or importance in the household environment. Households of R-CDI subjects in the peri-FMT period and of geographically matched and age-matched controls were analyzed for the presence ofC. difficile Household environmental surfaces and fecal samples from humans and pets in the household were examined. Households of post-FMT subjects were also examined (environmental surfaces only). Participants were surveyed regarding their personal history and household cleaning habits. Species identity and molecular characteristics of presumptive C. difficile isolates from environmental and fecal samples were determined by using the Pro kit (Remel, USA), Gram staining, PCR, toxinotyping, tcdC gene sequencing, and pulsed-field gel electrophoresis (PFGE). Environmental cultures detected C. difficile on ≥1 surface in 8/8 (100%) peri-FMT households, versus 3/8 (38%) post-FMT households and 3/8 (38%) control households (P= 0.025). The most common C. difficile-positive sites were the vacuum (11/27; 41%), toilet (8/30; 27%), and bathroom sink (5/29; 17%).C. difficile was detected in 3/36 (8%) fecal samples (two R-CDI subjects and one household member). Nine (90%) of 10 households with multiple C. difficile-positive samples had a single genotype present each. In conclusion,C. difficile was found in the household environment of R-CDI patients, but whether it was found as a cause or consequence of R-CDI is unknown. If household contamination leads to R-CDI, effective decontamination may be protective. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Colding, H; Bangsborg, J; Fiehn, N E
). To examine the taxonomic relevance of the ribosomal patterns of the 52 F. meningosepticum strains, the patterns were compared with existing DNA-DNA hybridization data with restriction enzymes PstI and HindIII. Ribotyping of the 52 F. meningosepticum strains showed banding patterns that could identify them...... correctly to one of the five genomic groups or subgroups. To assess the value of ribotyping for the interpretation of epidemiological data, the discriminatory power of the method was investigated for the 52 F. meningosepticum strains. With one to four restriction enzymes (PstI, HindIII, ClaI, Eco...
Dr. Jon Mark Hirshon, Associate Professor of Emergency Medicine at the University of Maryland School of Medicine, discusses Clostridium difficile infection in outpatients. Created: 11/7/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 11/21/2011.
Lavan, A H
BACKGROUND: Surveillance of Clostridium difficile infection (CDI) is an essential component of a CDI preventative programme. AIMS: The aim of this study was to evaluate two methods of CDI surveillance. METHODS: Prevalence of CDI, antibiotic use and associated co-morbidity was assessed weekly on two wards over 6 weeks. In addition, CDI incidence surveillance was performed on all new CDI cases over a 13-week period. Cases were assessed for CDI risk factors, disease severity, response to treatment and outcome at 6 months. RESULTS: Clostridium difficile infection prevalence was 3.5% (range 2.9-6.1%) on the medical ward and 1.1% (range 0-3.5%) on the surgical ward. Patients on the medical ward were older and more likely to be colonised with MRSA; however, recent antibiotic use was more prevalent among surgical patients. Sixty-one new CDI cases were audited. Patients were elderly (mean age 71 years) with significant co-morbidity (median age adjusted Charlson co-morbidity score 5). CDI ribotypes included 027 (29 cases) 078 (5) and 106 (4). Eight patients developed severe CDI, seven due to 027. Antibiotic use was common with 56% receiving three or more antibiotics in the preceding 8 weeks. Twenty-four patients had died at 6 months, five due to CDI. CONCLUSION: Clostridium difficile infection prevalence gives a broad overview of CDI and points to areas that require more detailed surveillance and requires little time. However, patient-based CDI incidence surveillance provides a more useful analysis of CDI risk factors, disease and outcome for planning preventative programmes and focusing antibiotic stewardship efforts.
Søes, Lillian Marie; Brock, Inger; Persson, Søren
The purpose of this study was to compare clinical features of Clostridium difficile infection (CDI) to toxin gene profiles of the strains isolated from Danish hospitalized patients. C. difficile isolates were characterized by PCR based molecular typing methods including toxin gene profiling...... and analysis of deletions and truncating mutations in the toxin regulating gene tcdC. Clinical features were obtained by questionnaire. Thirty percent of the CDI cases were classified as community-acquired. Infection by C. difficile with genes encoding both toxin A, toxin B and the binary toxin...... was significantly associated with hospital-acquired/healthcare-associated CDI compared to community-acquired CDI. Significantly higher leukocyte counts and more severe clinical manifestations were observed in patients infected by C. difficile containing genes also encoding the binary toxin together with toxin...
Pedersen, Karl; Dalsgaard, Inger; Larsen, J.L.
A total of 38 strains of atypical Aeromonas salmonicida, three oxidase-negative but otherwise typical Aer. salmonicida, three typical Aer. salmonicida, and two reference strains, isolated from several countries and fish species were examined with respect to rRNA gene restriction patterns (ribotypes...
Hargreaves, Katherine R; Flores, Cesar O; Lawley, Trevor D; Clokie, Martha R J
Clostridium difficile is an important human-pathogenic bacterium causing antibiotic-associated nosocomial infections worldwide. Mobile genetic elements and bacteriophages have helped shape C. difficile genome evolution. In many bacteria, phage infection may be controlled by a form of bacterial immunity called the clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR/Cas) system. This uses acquired short nucleotide sequences (spacers) to target homologous sequences (protospacers) in phage genomes. C. difficile carries multiple CRISPR arrays, and in this paper we examine the relationships between the host- and phage-carried elements of the system. We detected multiple matches between spacers and regions in 31 C. difficile phage and prophage genomes. A subset of the spacers was located in prophage-carried CRISPR arrays. The CRISPR spacer profiles generated suggest that related phages would have similar host ranges. Furthermore, we show that C. difficile strains of the same ribotype could either have similar or divergent CRISPR contents. Both synonymous and nonsynonymous mutations in the protospacer sequences were identified, as well as differences in the protospacer adjacent motif (PAM), which could explain how phages escape this system. This paper illustrates how the distribution and diversity of CRISPR spacers in C. difficile, and its prophages, could modulate phage predation for this pathogen and impact upon its evolution and pathogenicity. Clostridium difficile is a significant bacterial human pathogen which undergoes continual genome evolution, resulting in the emergence of new virulent strains. Phages are major facilitators of genome evolution in other bacterial species, and we use sequence analysis-based approaches in order to examine whether the CRISPR/Cas system could control these interactions across divergent C. difficile strains. The presence of spacer sequences in prophages that are homologous to phage genomes raises an
Álvarez-Pérez, Sergio; Blanco, José L; Harmanus, Celine; Kuijper, Ed J; García, Marta E
Despite extensive research on the epidemiology of pathogenic clostridia in dogs and cats, most published studies focus on a selected animal population and/or a single veterinary medical centre. We assessed the burden of Clostridium perfringens and C. difficile shedding by small animals in 17 veterinary clinics located within the Madrid region (Spain) and differing in size, number and features of animals attended and other relevant characteristics. In addition, we studied the genetic diversity and antibiotic susceptibility of recovered isolates. Selective culture of all fecal specimens collected during a single week from dogs (n = 105) and cats (n = 37) attended in participating clinics yielded C. perfringens/C. difficile from 31%, 4.8% of the dogs, and 20%, 0% of the cats analyzed, respectively, and three dogs yielded both species. Furthermore, 17 animals (15 dogs and two cats) that yielded a positive culture for either species were recruited for a follow-up survey and C. perfringens was again obtained from nine dogs. Considerable differences in prevalence were observed among participating clinics for both clostridial species. C. perfringens isolates (n = 109) belonged to toxinotypes A (97.2%) and E (three isolates from one dog), whereas C. difficile isolates (n = 18) belonged to the toxigenic ribotypes 106 (33.3%) and 154 (16.7%), a 009-like ribotype (33.3%) and an unknown non-toxigenic ribotype (16.7%). Amplified fragment length polymorphism-based fingerprinting classified C. perfringens and C. difficile isolates into 105 and 15 genotypes, respectively, and tested isolates displayed in vitro resistance to benzylpenicillin (2.8%, 88.8%), clindamycin (0%, 16.7%), erythromycin (0.9%, 16.7%), imipenem (1.8%, 100%), levofloxacin (0.9%, 100%), linezolid (5.5%, 0%), metronidazole (4.6%, 0%) and/or tetracycline (7.3%, 0%). All animals from which multiple isolates were retrieved yielded ≥2 different genotypes and/or antimicrobial susceptibility profiles
Martinelli, Massimo; Strisciuglio, Caterina; Veres, Gabor
BACKGROUND: Clostridium difficile infection is associated with pediatric inflammatory bowel disease (IBD) in several ways. We sought to investigate C. difficile infection in pediatric patients with IBD in comparison with a group of children with celiac disease and to evaluate IBD disease course o...
Bauer, Martijn Philippe
Clostridium difficile is a spore-forming bacterium, the toxin-producing strains of which cause colitis. Risk factors are antibiotics, advanced age and severe comorbidity. C. difficile infection (CDI) has been regarded as mostly a hospital-acquired infection. Preventing relapses is considered the
Brygge, K; Sørensen, C H; Colding, H
. The distribution of these types was found to be almost identical to the distribution among 16 M. catarrhalis strains cultured from middle ear exudates of 16 children with acute otitis media. Ribotype HAPA was found in two-thirds of all the cultures investigated, and 44% of the children harboured more than one...... ribotype in the nasopharynx at the same time. The vast majority of the nasopharyngeal M. catarrhalis cultures were beta-lactamase positive. One child had both a HAPA ribotype, beta-lactamase-negative strain in the nasopharyngeal secretions, and HAPA ribotype, beta-lactamase-positive strains at the entrance...... of the eustachian tube, the nasopharyngeal tonsils, the folds of the nasopharyngeal tonsils and the oropharynx. All except one of the M. catarrhalis strains cultured from middle ear exudates were beta-lactamase positive....
Dalsgaard, A.; Skov, M. N.; Serichantalergs, O.; Echeverria, P.
Pulsed-field gel electrophoresis (PFGE) of Cpo I-digested genomic DNA and ribotyping (Bgl I) were applied to 60 Vibrio cholerae strains including 48 V. cholerae O139 from Thailand to compare their value in differentiating strains of the present V. cholerae O139 epidemic. PFGE patterns were divided into groups A and B representing five and four subtypes, respectively, while ribotyping showed four different patterns. PFGE group B subtypes were only presented among O139 isolates from Thailand, w...
Fussing, V.; Wegener, Henrik Caspar
A total of 105 strains of H. somnus isolated from cattle in Denmark and other countries during 1982-1951 were compared with regard to biotypes (fermentation of 8 different sugars), plasmid profiles, Taq1 restriction endonuclease analysis of chromosomal DNA (REA-typing) and EcoRI-generated DNA...... restriction fragment length polymorphisms of rRNA genes (ribotyping). Eighty-four strains originating from cases of pneumonia, and 21 originating from the genitals of bulls were included in this study. Biotyping yielded 21 different types. Twenty-two of the isolates contained plasmids, and these were divided...... into 12 distinct plasmid profiles. Analysis of chromosomal DNA restriction patterns, resulted in 33 different REA patterns and 16 different ribopatterns in the investigated strains. Biotypes, REA-types, and ribotypes generally showed good correlation, whereas plasmid profiles did not correlate with any...
Fussing, V.; Wegener, Henrik Caspar
restriction fragment length polymorphisms of rRNA genes (ribotyping). Eighty-four strains originating from cases of pneumonia, and 21 originating from the genitals of bulls were included in this study. Biotyping yielded 21 different types. Twenty-two of the isolates contained plasmids, and these were divided......A total of 105 strains of H. somnus isolated from cattle in Denmark and other countries during 1982-1951 were compared with regard to biotypes (fermentation of 8 different sugars), plasmid profiles, Taq1 restriction endonuclease analysis of chromosomal DNA (REA-typing) and EcoRI-generated DNA...... into 12 distinct plasmid profiles. Analysis of chromosomal DNA restriction patterns, resulted in 33 different REA patterns and 16 different ribopatterns in the investigated strains. Biotypes, REA-types, and ribotypes generally showed good correlation, whereas plasmid profiles did not correlate with any...
Buňková, L.; Švec, P.; Halouzka, Jiří; Rudolf, Ivo; Němec, M.
Roč. 15, č. 2 (2008), s. 225-230 ISSN 1232-1966 R&D Projects: GA AV ČR KJB600930613; GA ČR GA206/03/0726 Institutional research plan: CEZ:AV0Z60930519 Keywords : Borrelia burgdorferi sensu lato * Czech Republic * ribotyping * whole-cell protein analysis * taxonomy Subject RIV: EE - Microbiology, Virology Impact factor: 1.443, year: 2008 http://www.aaem.pl/pdf/15225.pdf
Reller, Megan E; Lema, Clara A; Perl, Trish M; Cai, Mian; Ross, Tracy L; Speck, Kathleen A; Carroll, Karen C
We examined the incremental yield of stool culture (with toxin testing on isolates) versus our two-step algorithm for optimal detection of toxigenic Clostridium difficile. Per the two-step algorithm, stools were screened for C. difficile-associated glutamate dehydrogenase (GDH) antigen and, if positive, tested for toxin by a direct (stool) cell culture cytotoxicity neutralization assay (CCNA). In parallel, stools were cultured for C. difficile and tested for toxin by both indirect (isolate) CCNA and conventional PCR if the direct CCNA was negative. The "gold standard" for toxigenic C. difficile was detection of C. difficile by the GDH screen or by culture and toxin production by direct or indirect CCNA. We tested 439 specimens from 439 patients. GDH screening detected all culture-positive specimens. The sensitivity of the two-step algorithm was 77% (95% confidence interval [CI], 70 to 84%), and that of culture was 87% (95% CI, 80 to 92%). PCR results correlated completely with those of CCNA testing on isolates (29/29 positive and 32/32 negative, respectively). We conclude that GDH is an excellent screening test and that culture with isolate CCNA testing detects an additional 23% of toxigenic C. difficile missed by direct CCNA. Since culture is tedious and also detects nontoxigenic C. difficile, we conclude that culture is most useful (i) when the direct CCNA is negative but a high clinical suspicion of toxigenic C. difficile remains, (ii) in the evaluation of new diagnostic tests for toxigenic C. difficile (where the best reference standard is essential), and (iii) in epidemiologic studies (where the availability of an isolate allows for strain typing and antimicrobial susceptibility testing).
Clostridium difficile is a common cause of diarrhea in healthcare settings but little is known about what causes cases in the community. In this podcast, CDC's Dr. L. Clifford McDonald discusses two papers in the May 2009 edition of Emerging Infectious Diseases that explore whether the organism could be found in meat samples purchased in grocery stores in Arizona and Canada. Created: 4/16/2009 by Emerging Infectious Diseases. Date Released: 4/16/2009.
Full Text Available Clostridium difficile is an emerging pathogen that causes C difficile-associated diarrhea, an important nosocomial infection. Control of this infection remains a challenge, and much needs to be determined about the antimicrobial resistance of the organism, antibiotic stewardship, contamination of the patient environment, and various host factors that determine susceptibility or resistance to infection. A national symposium focusing on C difficile infections, the Clostridium difficile Symposium on Emerging Issues and Research, was hosted on November 23, 2004, by the Department of Medical Microbiology and Infectious Diseases at the University of Manitoba, Winnipeg, Manitoba, in partnership with the Canadian Institutes of Health Research. This symposium, which aimed to summarize key research issues regarding C difficile infections in Canada, had the following objectives: to provide a forum for learning and discussion about C difficile and its impact on the health of Canadians; to identify the key research issues that should be addressed; and to explore potential research funding opportunities and collaboration. The present report summarizes key research issues identified for C difficile infections in Canada by addressing four major themes: diagnosis and surveillance, infection prevention and control, antibiotic stewardship, and clinical management.
Michael R. Simon
Full Text Available Clostridium difficile infection has emerged as a growing worldwide health problem. The colitis of Clostridium difficile infection results from the synergistic action of C. difficile secreted toxins A and B upon the colon mucosa. A human monoclonal IgG anti-toxin has demonstrated the ability in combination therapy to reduce mortality in C. difficile challenged hamsters. This antibody is currently in a clinical trial for the treatment of human Clostridium difficile infection. More than one group of investigators has considered using polyclonal bovine colostral antibodies to toxins A and B as an oral passive immunization. A significant proportion of the healthy human population possesses polyclonal antibodies to the Clostridium difficile toxins. We have demonstrated that polyclonal IgA derived from the pooled plasma of healthy donors possesses specificity to toxins A and B and can neutralize these toxins in a cell-based assay. This suggests that secretory IgA prepared from such pooled plasma IgA may be able to be used as an oral treatment for Clostridium difficile infection.
The aim of the present study was to examine the genomic relationship among 112 Actinobacillus pleuropneumoniae serotype 2 strains obtained throughout Europe and North America. HindIII ribotyping of the strains resulted in five ribotypes of high similarity (87-98%). Sequence analysis of the riboso......The aim of the present study was to examine the genomic relationship among 112 Actinobacillus pleuropneumoniae serotype 2 strains obtained throughout Europe and North America. HindIII ribotyping of the strains resulted in five ribotypes of high similarity (87-98%). Sequence analysis...... of the ribosomal intergenic region of strains representing each ribotype and each country showed no differences. A common ribotype was further characterized by PFGE of 12 strains representing all countries. The resultant five PFGE patterns of European strains showed a similarity of more than 91%, to which the two...
Clostridium difficile is an antibiotic-resistant bacterium that causes diarrhea and sometimes serious intestinal illnesses. In recent years, C. difficile infections have been increasing in number and severity, including among some people outside healthcare settings. In this podcast, CDC's Dr. Michael Jhung discusses his recent study that looked at a new, increasingly prevalent strain of C. difficile in people and compared it to a strain historically found in animals to see whether the two might be linked. The study is published in the July 2008 issue of Emerging Infectious Diseases. Created: 6/30/2008 by Emerging Infectious Diseases. Date Released: 7/3/2008.
McFarland, Lynne Vernice; Ozen, Metehan; Dinleyici, Ener Cagri; Goh, Shan
Antibiotic-associated diarrhea (AAD) and Clostridium difficile infections (CDI) have been well studied for adult cases, but not as well in the pediatric population. Whether the disease process or response to treatments differs between pediatric and adult patients is an important clinical concern when following global guidelines based largely on adult patients. A systematic review of the literature using databases PubMed (June 3, 1978-2015) was conducted to compare AAD and CDI in pediatric and adult populations and determine significant differences and similarities that might impact clinical decisions. In general, pediatric AAD and CDI have a more rapid onset of symptoms, a shorter duration of disease and fewer CDI complications (required surgeries and extended hospitalizations) than in adults. Children experience more community-associated CDI and are associated with smaller outbreaks than adult cases of CDI. The ribotype NAP1/027/BI is more common in adults than children. Children and adults share some similar risk factors, but adults have more complex risk factor profiles associated with more co-morbidities, types of disruptive factors and a wider range of exposures to C. difficile in the healthcare environment. The treatment of pediatric and adult AAD is similar (discontinuing or switching the inciting antibiotic), but other treatment strategies for AAD have not been established. Pediatric CDI responds better to metronidazole, while adult CDI responds better to vancomycin. Recurrent CDI is not commonly reported for children. Prevention for both pediatric and adult AAD and CDI relies upon integrated infection control programs, antibiotic stewardship and may include the use of adjunctive probiotics. Clinical presentation of pediatric AAD and CDI are different than adult AAD and CDI symptoms. These differences should be taken into account when rating severity of disease and prescribing antibiotics.
McFarland, Lynne Vernice; Ozen, Metehan; Dinleyici, Ener Cagri; Goh, Shan
Antibiotic-associated diarrhea (AAD) and Clostridum difficile infections (CDI) have been well studied for adult cases, but not as well in the pediatric population. Whether the disease process or response to treatments differs between pediatric and adult patients is an important clinical concern when following global guidelines based largely on adult patients. A systematic review of the literature using databases PubMed (June 3, 1978-2015) was conducted to compare AAD and CDI in pediatric and adult populations and determine significant differences and similarities that might impact clinical decisions. In general, pediatric AAD and CDI have a more rapid onset of symptoms, a shorter duration of disease and fewer CDI complications (required surgeries and extended hospitalizations) than in adults. Children experience more community-associated CDI and are associated with smaller outbreaks than adult cases of CDI. The ribotype NAP1/027/BI is more common in adults than children. Children and adults share some similar risk factors, but adults have more complex risk factor profiles associated with more co-morbidities, types of disruptive factors and a wider range of exposures to C. difficile in the healthcare environment. The treatment of pediatric and adult AAD is similar (discontinuing or switching the inciting antibiotic), but other treatment strategies for AAD have not been established. Pediatric CDI responds better to metronidazole, while adult CDI responds better to vancomycin. Recurrent CDI is not commonly reported for children. Prevention for both pediatric and adult AAD and CDI relies upon integrated infection control programs, antibiotic stewardship and may include the use of adjunctive probiotics. Clinical presentation of pediatric AAD and CDI are different than adult AAD and CDI symptoms. These differences should be taken into account when rating severity of disease and prescribing antibiotics. PMID:27003987
This 60 second PSA is based on the March 2012 CDC Vital Signs report. C. difficile is a germ that causes diarrhea linked to 14,000 deaths in the US each year. This podcast helps health care professionals learn how to prevent C. difficile infections. Created: 3/6/2012 by Centers for Disease Control and Prevention (CDC). Date Released: 3/6/2012.
Gil, Fernando; Lagos-Moraga, Sebastián; Calderón-Romero, Paulina; Pizarro-Guajardo, Marjorie; Paredes-Sabja, Daniel
Clostridium difficile is a Gram-positive, anaerobic spore former, and an important nosocomial pathogenic bacterium. C. difficile spores are the morphotype of transmission and recurrence of the disease. The formation of C. difficile spores and their subsequent germination are essential processes during the infection. Recent in vitro and in vivo work has shed light on how spores are formed and the timing of in vivo sporulation in a mouse model. Advances have also been made in our understanding of the machineries involved in spore germination, and how antibiotic-induced dysbiosis affects the metabolism of bile salts and thus impacts C. difficile germination in vivo. Studies have also attempted to identify how C. difficile spores interact with the host's intestinal mucosa. Spore resistance has also been revisited by several groups highlighting the extreme resistance of this morphotype to traditional food processing regimes and disinfectants used in clinical settings. Therefore, the aim of this review is to summarize recent advances on spore formation/germination in vitro and in vivo, spore-host interactions, and spore resistance that contribute to our knowledge of the role of C. difficile spores in the infectious process. Copyright © 2017. Published by Elsevier Ltd.
O'Connor, K A
BACKGROUND: Broad-spectrum antibiotics, particularly intravenous cephalosporins, are associated with Clostridium difficile diarrhoea. Diarrhoea due to C. difficile is a growing problem in hospitals, especially among elderly patients. AIM: To establish whether changing an antibiotic policy with the aim of reducing the use of injectable cephalosporins leads to a reduction in the incidence of C. difficile diarrhoea in elderly patients. DESIGN: Retrospective analysis. METHODS: A group of patients who were subject to the new antibiotic policy from the period following July 2000, were compared with patients who were admitted prior to July 2000 and were not subject to the new policy. Infections, antibiotic prescriptions and mortality rates were determined from case notes, and C. difficle diarrhoea rates from microbiological data. RESULTS: Intravenous cephalosporin use fell from 210 to 28 defined daily doses (p < 0.001) following the change in antibiotic policy, with a corresponding increase in piperacillin-tazobactam (p < 0.001) and moxifloxacin (p < 0.001) use. The new policy led to a significant reduction in C. difficile diarrhoea cases. The relative risk of developing C. difficile infection with the old policy compared to the new policy was 3.24 (95%CI 1.07-9.84, p = 0.03). DISCUSSION: The antibiotic policy was successfully introduced into an elderly care service. It reduced both intravenous cephalosporin use and C. difficile diarrhoea.
Hall, James A; Keul, Ryan R; Shanks, Justin D; Fader, Robert; Herrington, Jon D
The purpose of this study was to evaluate alcohol-based dispensers as potential fomites for Clostridium difficile. A convenience sample of 120 alcohol-based dispensers was evaluated for the presence of C difficile either by culture or polymerase chain reaction for C difficile toxin. The results demonstrated that C difficile was not cultured, and C difficile toxin was not detected using polymerase chain reaction; however, gram-positive rods, Clostridium perfringens, Pantoea agglomerans, coagulase-negative Staphylococcus, Peptostreptococcus, Bacillus spp, and microaerophilic Streptococcus were present within the overflow basins of the alcohol-based dispensers. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Full Text Available OBJECTIVE: Clostridium difficile-associated diarrhea is a major problem in adults. The present study was conducted to assess risk factors and outcomes in children with C difficile-associated diarrhea.
María E Negrón
Full Text Available BACKGROUND: The impact of Clostridium difficile infections among ulcerative colitis (UC patients is well characterized. However, there is little knowledge regarding the association between C difficile infections and postoperative complications among UC patients.
Fussing, V.; Barfod, Kristen; Nielsen, R.
. Airborne transmission from neighboring conventional pig farms was investigated in 12 cases of infected SPF herds. Transmission via vehicles transporting pigs between SPF herds was investigated in nine cases while transmission by trading of pigs between SPF herds was investigated in two cases. Serotype 2...... was isolated from all SPF herds included in this study, except one, emphasizing the high prevalence of this serotype in Denmark. By ribotyping, airborne transmission was indicated in five of 12 cases, transmission via pig transporting vehicle was indicated in six of nine cases, and transmission via trading...
Janet Yakubu Nale
Full Text Available Clostridium difficile infection (CDI is a global health threat associated with high rates of morbidity and mortality. Conventional antibiotic CDI therapy can result in treatment failure and recurrent infection. C. difficile produces biofilms which contribute to its virulence and impair antimicrobial activity. Some bacteriophages (phages can penetrate biofilms and thus could be developed to either replace or supplement antibiotics. Here, we determined the impact of a previously optimized 4-phage cocktail on C. difficile ribotype 014/020 biofilms, and additionally as adjunct to vancomycin treatment in Galleria mellonella larva CDI model. The phages were applied before or after biofilm establishment in vitro, and the impact was analyzed according to turbidity, viability counts and topography as observed using scanning electron and confocal microscopy. The infectivity profiles and efficacies of orally administered phages and/or vancomycin were ascertained by monitoring colonization levels and larval survival rates. Phages prevented biofilm formation, and penetrated established biofilms. A single phage application reduced colonization causing extended longevity in the remedial treatment and prevented disease in the prophylaxis group. Multiple phage doses significantly improved the larval remedial regimen, and this treatment is comparable to vancomycin and the combined treatments. Taken together, our data suggest that the phages significantly reduce C. difficile biofilms, and prevent colonization in the G. mellonella model when used alone or in combination with vancomycin. The phages appear to be highly promising therapeutics in the targeted eradication of CDI and the use of these models has revealed that prophylactic use could be a propitious therapeutic option.
Bauer, Martijn P; Notermans, Daan W; van Benthem, Birgit H B
Little is known about the extent of Clostridium difficile infection in Europe. Our aim was to obtain a more complete overview of C difficile infection in Europe and build capacity for diagnosis and surveillance.......Little is known about the extent of Clostridium difficile infection in Europe. Our aim was to obtain a more complete overview of C difficile infection in Europe and build capacity for diagnosis and surveillance....
Full Text Available Ribotyping has been widely used to characterise the seventh pandemic clone including South American and O139 variants which appeared in 1991 and 1992 respectively. To reveal the molecular basis of ribotype variation we analysed the rrn operons and their flanking regions. All but one variation detected by BglI, the most discriminatory enzyme, was found to be due to changes within the rrn operons, resulting from recombination between operons. The recombinants are detected because of the presence of a BglI site in the 16S gene in three of the nine rrn operons and/or changes of intergenic spacer types of which four variants were identified. As the frequency of rrn recombination is high, ribotyping becomes a less useful tool for evolutionary studies and long term monitoring of the pathogenic clones of Vibrio cholerae as variation could undergo precise reversion by the same recombination event.
Sewell, Bernadette; Rees, Eugene; Thomas, Ian; Ch'ng, Chin Lye; Isaac, Mike; Berry, Nidhika
A study was performed to assess the cost of a rapid molecular assay (PCR) for diagnosis of Clostridium difficile infection (CDI) and the impact of its routine use on patient length of stay (LOS) in comparison with cell culture cytotoxin neutralization assay (CCNA). From March 2011 to September 2011, Xpert(®) C. difficile (Cepheid, Sunnyvale, CA, USA) PCR was used on patients with suspicion of CDI in two acute care hospitals in Abertawe Bro Morgannwg University Health Board, Swansea, Wales, UK. Test results were used for patient management. LOS and time to reportable result were compared for negative and positive prospective patients tested by PCR and historic control patients tested by CCNA during March 2010 to September 2010. Tests were priced using micro-costing and a cost comparison analysis was undertaken. In total, 506 patients were included. Time to reportable result for PCR samples was 1.53 h compared to 46.54 h for CCNA negatives and 22.45 h for CCNA positives. Patients tested by CCNA stayed 4.88 days longer in hospital compared to PCR patients if they tested positive and 7.03 days if tests were negative. The mean reduction in LOS observed in our study has the potential to generate cost savings of up to £2,292.62 for every patient with suspected CDI, if samples were to be tested routinely with PCR instead of CCNA. A rapid molecular test for C. difficile in an acute hospital setting produced quick results that led to a decrease in LOS compared to historic CCNA control patients. This could result in considerable savings through reduced excess inpatient days.
Lejko-Zupanc, T; Zakelj, J; Strle, F; Janc, M; Pleterski-Rigler, D
The influence of long-term ceftriaxone administration on the emergence of Clostridium difficile was studied with 80 patients receiving ceftriaxone for 14 days. In five patients (6.3%) C. difficile was cultured. The appearance of gastrointestinal disturbances during treatment with ceftriaxone was common, but the rate of emergence of C. difficile in immunocompetent patients was not high.
Qutub, Mohammed; Govindan, Parasanth; Vattappillil, Anupama
Abstract Background Clostridium difficile-associated diarrhea (CDAD) is the commonest cause of nosocomial diarrhea. Methods for C.difficle detection include toxins or enzyme detection by immunoassays, cytotoxicity neutralization assay (CCNA) or FDA approved PCR. Due to the tedious and time consuming nature of the CCNA and the suboptimal specificity and sensitivity of EIAs, these assays cannot be used as stand-alone tests. One approach of combining these assays, is by two-step algorithm, where Ag-EIAs is used as screening test and confirmation of positives either by a toxin detection enzyme immunoassays or by CCNA. Another approach is a three-step algorithm, where Ag-EIAs is used as screening test, and all positives are tested by a toxin detection EIA and if toxin detection negative, further tested either by PCR or by CCNA. Therefore we aimed to evaluate a new two-step algorithm for the detection of toxigenic CD and its role in improvement of turn-around-time. Methods A total of 3518 nonformed stool specimens from suspected cases of CDAD were collected. Specimens were tested either by GDH-toxin A/B ICA; or by GeneXpert C. diificile PCR as per the algorithm (Figure 1). Results Of 3518 stool specimens tested; 130 (3.70%) were positive and 2989 (84.96%) were negative by GDH-toxin A/B ICA while 399 (11.34%) required PCR. None of the negative GDH and positive toxin A/B samples tested positive by PCR. Also, none of the negative GDH and negative toxin A/B samples tested positive by PCR (Figure 2). Conclusion Study indicates that when the GDH-toxin A/B ICA is used, almost 89 % of the results could be reported within 30 minutes; about 3.7 % of them being positive results and 84.96 % being negative. Confirmation of the discrepant GDH and Toxin A/B results was by PCR. The new algorithm offered rapid detection of C.difficile by ICA, judicious use of PCR and effectively reduced turnaround time. Figure-1: Two-step algorithm for C difficile testing. Figure-2: Results of two
Zhang, Lihua; Dong, Danfeng; Jiang, Cen; Li, Zhen; Wang, Xuefeng; Peng, Yibing
Clostridium difficile is well recognized as the common pathogen of nosocomial diarrhea, meanwhile, asymptomatic colonization with C. difficile in part of the population has also drawn public attention. Although gut microbiota is known to play an important role in the pathogenesis of C. difficile infection (CDI), whether there is any alteration of gut microbial composition in asymptomatic C. difficile carriers hasn't been clearly described. The purpose of this study was to explore the differences in gut microbiome among CDI patients, asymptomatic C. difficile carriers and healthy individuals. We performed fecal microbiota analysis on the samples of eight CDI patients, eight asymptomatic C. difficile carriers and nine healthy subjects using 16S rRNA gene pyrosequencing. CDI patients and asymptomatic carriers showed reduced microbial richness and diversity compared with healthy subjects, accompanied with a paucity of phylum Bacteroidetes and Firmicutes as well as an overabundance of Proteobacteria. Some normally commensal bacteria, especially butyrate producers, were significantly depleted in CDI patients and asymptomatic carriers. Furthermore, the differences observed in microbial community structure between CDI patients and asymptomatic carriers suggested that the gut microbiota may be a potential factor of disease state for CDI. Our study demonstrates the characterization and diversity of gut microbiota in CDI and asymptomatic C. difficile colonization, which will provide new ideas for surveillance of the disease state and development of microbiota-targeted agents for CDI prevention and treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.
Murad, Yanal M; Perez, Justo; Nokhbeh, Reza; Ybazeta, Gustavo; Dewar, Brenda; Lefebvre, Sebastien; Diaz-Mitoma, Francisco
Two rapid methods of Clostridium difficile infection (CDI) diagnosis were compared between June 2012 and March 2013: a GeneXpert (Cepheid, Sunnyvale, Calif) polymerase chain reaction (PCR) test and an enzyme immunoassay (EIA). The influence of these methods on the detection of hospital-acquired CDI and identification of CDI outbreaks was evaluated. We tested 1,592 stool samples for C difficile. The GeneXpert PCR test identified 211 positive samples (68 determined to be hospital-acquired infection), whereas EIA identified 105 positive samples (36 determined to be hospital-acquired infection). The GeneXpert PCR method in contrast to the EIA method increased the detection rates of nosocomial CDI cases and contributed to the declaration of CDI outbreaks. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Harvey, Roger B; Norman, Keri N; Andrews, Kathleen; Hume, Michael E; Scanlan, Charles M; Callaway, Todd R; Anderson, Robin C; Nisbet, David J
The incidence and severity of disease associated with toxigenic Clostridium difficile have increased in hospitals in North America from the emergence of newer, more virulent strains. Toxigenic C. difficile has been isolated from food animals and retail meat with potential implications of transfer to human beings. The objective of the present study was to determine the prevalence of toxigenic C. difficile in chickens and retail poultry meat in Texas. Seven C. difficile isolates were detected in fecal samples of 300 (2.3%) broiler chickens. Three cultivation procedures were evaluated for isolation of C. difficile from poultry meat and detected 1/32 (3.1%), 2/32 (6.2%), and 4/32 (12.5%) for the three procedures, respectively. Chicken and poultry meat isolates were characterized as toxinotype V and pulsed-field gel electrophoresis gel type-NAP7 or NAP7-variant. Susceptibilities to 11 antimicrobial agents in the current study suggested somewhat reduced resistance than reported for other meat or animal toxinotype V isolates.
von Müller, Lutz
Clostridium difficile infection (CDI) is a frequent and complex disease which is influenced by the repertoire of bacterial virulence factors, by host immunity and by the intestinal microbiome. These complex interaction opens a number of options which may be used for treatment in the future. One example for new treatment options is fecal microbiota transplantation (FMT). Driven by C. difficile related research activities the knowledge of protective microorganism is increasing and it may be assumed that bacteriotherapy by next-generation probiotics may be used very soon also for other diseases. Very often, CDI reflects to the clinician that antibiotic therapy is associated with side effects. Therefore, C. difficile is the guilty conscience which helps to implement targeted and restrictive antibiotic use in the daily practice. © Georg Thieme Verlag KG Stuttgart · New York.
Full Text Available The epidemiology of Clostridium difficile infection (CDI has changed over time and between countries. It is therefore essential to monitor the characteristics of patients at risk of infection and the circulating strains to recognize local and global trends, and improve patient management. From December 2011 to May 2012 we conducted a prospective, observational epidemiological study of patients with laboratory-confirmed CDI at two tertiary teaching hospitals in Perth, Western Australia to determine CDI incidence and risk factors in an Australian setting. The incidence of CDI varied from 5.2 to 8.1 cases/10 000 occupied bed days (OBDs at one hospital and from 3.9 to 16.3/10 000 OBDs at the second hospital. In total, 80 patients with laboratory-confirmed CDI met eligibility criteria and consented to be in the study. More than half (53.8% had hospital-onset disease, 28.8% had community-onset and healthcare facility-associated disease and 7.5% were community-associated infections according to the definitions used. Severe CDI was observed in 40.0% of these cases but the 30-day mortality rate for all cases was only 2.5%. Besides a shorter length of stay among cases of community-onset CDI, no characteristics were identified that were significantly associated with community-onset or severe CDI. From 70 isolates, 34 different ribotypes were identified. The predominant ribotypes were 014 (24.3%, 020 (5.7%, 056 (5.7% and 070 (5.7%. Whereas this study suggests that the characteristics of CDI cases in Australia are not markedly different from those in other developed countries, the increase in CDI rate observed emphasizes the importance of surveillance.
Berry, N; Sewell, B; Jafri, S; Puli, C; Vagia, S; Lewis, A M; Davies, D; Rees, E; Ch'ng, C L
To determine the clinical utility of a rapid molecular assay for Clostridium difficile infection (CDI) in an acute hospital setting. From March to September 2011, stool specimens from inpatients in two acute hospitals with suspected CDI were tested prospectively by routine cell culture cytotoxin neutralization assay (CCNA), real-time polymerase chain reaction (PCR) using the GeneXpert (Cepheid Inc., Sunnyvale, CA, USA), and a dual testing algorithm [glutamate dehydrogenase (GDH)/toxin enzyme immuno-assay, Premier, Launch Diagnostics, Longfield, UK]. All patients with positive PCR, CCNA or discrepant results were reviewed by a multi-disciplinary team (treating clinician, gastroenterologist, microbiologist and infection control nurse). C. difficile detection rates were 11.7% (PCR), 6% (CCNA) and 13.8% (GDH). Out of 1034 stool specimens included in the study, 974 (94.1%) had concordant CCNA and PCR results. Eighty-nine percent (886/985) had concordant CCNA, PCR and GDH results, and 94.4% (930/985) had concordant GDH and PCR results. Using clinical diagnosis as the reference, PCR had sensitivity of 99.1%, specificity of 98.9%, positive predictive value (PPV) of 91.9% and negative predictive value (NPV) of 99.9%. CCNA on a single sample had sensitivity of 51%, specificity of 99.4%, PPV of 91.9% and NPV of 94.3%. GDH had sensitivity of 83.8%, specificity of 94.5%, PPV of 64.7% and NPV of 97.9%. Almost twice as many patients were positive by PCR compared with CCNA (121 vs 62); 54/59 of those with discrepant results were clinically confirmed as CDI. Rapid diagnosis of CDI using PCR was timely, accurate and correlated well with clinical diagnosis. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Aarestrup, Frank Møller; Wegener, Henrik Caspar; Jensen, N.E.
This study was conducted to investigate the geographical distribution of phage and ribotypes of Staphylococcus aureus causing bovine mastitis in the 5 Nordic countries. A total of 403 isolates of S. aureus was isolated from 403 different dairy herds. One hundred five strains were isolated in Denm...
Reinink, Andrew R; Limsrivilai, Julajak; Reutemann, Bethany A; Feierabend, Tristan; Briggs, Emily; Rao, Krishna; Higgins, Peter D R
Clostridium difficile infection (CDI) frequently complicates ulcerative colitis (UC) and can mimic disease flare. Differentiating UC flare from CDI remains a clinical challenge, particularly due to C. difficile colonization. Procalcitonin (PCT) is a serum biomarker for bacterial infections. We hypothesized that PCT would differentiate acute CDI from UC flare and C. difficile colonization. A single-center prospective cohort study was conducted from 2013 to 2016. All UC patients with a stool sample for C. difficile testing were eligible. A total of 117 patients were enrolled, while 20 were excluded. Chart review was performed. Among 27 patients with CDI, median PCT was 60.7 (range 26-560.6) pg/mL, while among 90 patients without CDI, median PCT was 56.7 (range 25.1-2,252) pg/mL (p = 0.9). It was found that 14 patients with CDI responded completely to C. difficile treatment (CDI-R), while 8 patients did not and were diagnosed with UC flare (CDI-NR). For CDI-R, median PCT was 104.5 (range 26.3-560.6), compared to 40.3 (range 26.0-116.3) for CDI-NR (p = 0.036). In UC patients presenting with diarrhea, serum PCT was not significantly higher in UC patients with positive C. difficile testing. However, PCT was significantly elevated in CDI-R versus CDI-NR, suggesting that PCT may have utility in making this discrimination. © 2017 S. Karger AG, Basel.
The pathogenesis of recurrent Clostridium difficile infection (CDI) is still poorly understood. The risk of recurrence is approximately 20% after an initial CDI episode and dramatically increases with subsequent CDI recurrences. Several factors may play a role in recurrent CDI (rCDI), including conditions influencing germination, metabolic pathways that influence toxin production of C. difficile, and the microbiota composition offering protection against colonization and disease caused by C. difficile. Paradoxically, the currently recommended treatment for acute symptomatic CDI, i.e. metronidazole or vancomycin, can cause modification of the intestinal flora. Indeed, administration of anti-CDI antibiotics leads to suppression of C. difficile, along with collateral damage of the protective intestinal microbiota and opening of a "window of vulnerability" for recurrence. Host factors also have a prominent role, including innate and acquired humoral immunity, i.e. passive antibodies administration or active vaccination as a prevention strategy. They play a crucial role in the protection against severe and recurrent CDI. The assessment of risk factors of recurrence and modeling prediction scores could help in preventing the troublesome experience of CDI recurrence. Six studies have methodologically assessed prediction scores for rCDI. However, the definition of recurrence was heterogeneous, external validation was often not performed, and immunological factors were often not considered. There is a need for further studies on the pathophysiology of recurrence to design models for prediction that are sound and applicable in clinical practice. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Full Text Available Clostridium (C. difficile is a typical representative of the genus Clostridium. After colonization of the intestinal tract, toxigenic C. difficile strains are capable to produce two exotoxins, enterotoxin (toxin A and cytotoxin (toxin B, which cause diarrhea and colitis. Toxin A binds to specific carbohydrate receptors on the surface of intestinal cells and this is the beginning of damages in the intestinal tract which include destruction of the villi epithelium, limiting membrane, intercellular connections (zonula occludens and surface of the mucosa. If only toxin B is injected into intestinal cells, it does not cause damage nor increased fluids secretion. Probably, the reason for this is the inability of the toxin to bind to the cell membrane receptor in the intestinal tract under normal physiological conditions. Toxigenic strains of C. difficile can be found in the intestines of healthy people, without any symptoms or clinical signs (asymptomatic colonization. However, in people with risk factors, they can cause diarrhea of varying severity and life-threatening pseudomembranous colitis. These diseases are known as C. difficile associated disease - CDAD.
Full Text Available During the last decade, Clostridium difficile infection showed a dramatic increase in incidence and virulence in the Northern hemisphere. This incessantly challenging disease is the leading cause of antibiotic-associated and nosocomial infectious diarrhea and became life-threatening especially among elderly people. It is generally assumed that all human bacterial pathogens are heterotrophic organisms, being either saccharolytic or proteolytic. So far, this has not been questioned as colonization of the human gut gives access to an environment, rich in organic nutrients. Here, we present data that C. difficile (both clinical and rumen isolates is also able to grow on CO2+H2 as sole carbon and energy source, thus representing the first identified autotrophic bacterial pathogen. Comparison of several different strains revealed high conservation of genes for autotrophic growth and showed that the ability to use gas mixtures for growth decreases or is lost upon prolonged culturing under heterotrophic conditions. The metabolic flexibility of C. difficile (heterotrophic growth on various substrates as well as autotrophy could allow the organism in the gut to avoid competition by niche differentiation and contribute to its survival when stressed or in unfavorable conditions that cause death to other bacteria. This may be an important trait for the pathogenicity of C. difficile.
Full Text Available The incidence and mortality rate of Clostridium difficile infection have increased remarkably in both hospital and community settings during the last two decades. The growth of infection may be caused by multiple factors including inappropriate antibiotic usage, poor standards of environmental cleanliness, changes in infection control practices, large outbreaks of C. difficile infection in hospitals, alteration of circulating strains of C. difficile, and spread of hypervirulent strains. Detection of high-risk populations could be helpful for prompt diagnosis and consequent treatment of patients suffering from C. difficile infection. Metronidazole and oral vancomycin are recommended antibiotics for the treatment of initial infection. Current treatments for C. difficile infection consist of supportive care, discontinuing the unnecessary antibiotic, and specific antimicrobial therapy. Moreover, novel approaches include fidaxomicin therapy, monoclonal antibodies, and fecal microbiota transplantation mediated therapy. Fecal microbiota transplantation has shown relevant efficacy to overcome C. difficile infection and reduce its recurrence.
Rineh, Ardeshir; Kelso, Michael J; Vatansever, Fatma; Tegos, George P; Hamblin, Michael R
The Gram-positive anaerobic bacterium Clostridium difficile produces toxins A and B, which can cause a spectrum of diseases from pseudomembranous colitis to C. difficile-associated diarrhea. A limited number of C. difficile strains also produce a binary toxin that exhibits ADP ribosyltransferase activity. Here, the structure and the mechanism of action of these toxins as well as their role in disease are reviewed. Nosocomial C. difficile infection is often contracted in hospital when patients treated with antibiotics suffer a disturbance in normal gut microflora. C. difficile spores can persist on dry, inanimate surface for months. Metronidazole and oral vancomycin are clinically used for treatment of C. difficile infection but clinical failure and concern about promotion of resistance are motivating the search for novel non-antibiotic therapeutics. Methods for controlling both toxins and spores, replacing gut microflora by probiotics or fecal transplant, and killing bacteria in the anaerobic gut by photodynamic therapy are discussed.
Sell, T L; Schaberg, D R; Fekety, F R
The study of the epidemiology of infection with Clostridium difficile would be aided by a way to type individual bacterial isolates. We therefore sought bacteriophages for use in typing. With mitomycin C exposure (3 micrograms/ml), filtrates from 10 strains of C. difficile had plaque-forming lytic activity on other C. difficile strains. Individual phage were passaged and made into high-titer stock preparations for typing. Electron microscopy revealed tailed phage particles from one such prepa...
Nanayakkara, Deepa; Nanda, Neha
Clostridium difficile infection (CDI) is a major healthcare-associated infection that causes significant morbidity and an economic impact in the United States. In this review, we provide an overview of Clostridium difficile infection in solid organ transplant recipients with an emphasis on recent literature. C. difficile in solid organ transplant population has unique risk factors. Fecal microbiota transplantation has shown favorable results in treatment of recurrent C. difficile in this population. Preliminary data from animal studies suggests excellent efficacy with immunization against C. difficile toxins. Over the last decade, number of individuals receiving solid organ transplants has increased exponentially making peri-transplant complications a common occurrence.C. difficile is a frequent cause of morbidity in solid organ transplant recipients. Early and accurate diagnosis of C. difficile requires a stepwise approach. Differentiating between asymptomatic carriage and infection is a diagnostic challenge. Microbial diversity is inversely proportional to risk of C. difficile infection. Antimicrobial stewardship programs help to retain microbial diversity in individuals susceptible to CDI. Recurrent or relapsing C. difficile infection require fecal microbiota transplantation for definitive cure.
Beck, Eric T; Buchan, Blake W; Riebe, Katherine M; Alkins, Brenda R; Pancholi, Preeti; Granato, Paul A; Ledeboer, Nathan A
Clostridium difficile is a Gram-positive bacterium commonly found in health care and long-term-care facilities and is the most common cause of antibiotic-associated diarrhea. Rapid detection of this bacterium can assist physicians in implementing contact precautions and appropriate antibiotic therapy in a timely manner. The purpose of this study was to compare the clinical performance of the Quidel Lyra Direct C. difficile assay (Lyra assay) (Quidel, San Diego, CA) to that of a direct cell culture cytotoxicity neutralization assay (CCNA) and enhanced toxigenic culture. This study was performed at three geographically diverse laboratories within the United States using residual stool specimens submitted for routine C. difficile testing. Residual samples were tested using the Lyra assay on three real-time PCR platforms, and results were compared to those for direct CCNA and enhanced toxigenic culture. The test results for all platforms were consistent across all three test sites. The sensitivity and specificity of the Lyra assay on the SmartCycler II, ABI 7500 Fast DX, and ABI QuantStudio DX instruments compared to CCNA were 90.0% and 93.3%, 95.0% and 94.2%, and 93.8% and 95.0%, respectively. Compared to enhanced toxigenic culture, the sensitivity and specificity of the Lyra assay on the SmartCycler II, ABI 7500, and QuantStudio instruments were 82.1% and 96.9%, 89.3% and 98.8%, and 85.7% and 99.0%, respectively. Overall, the Lyra assay is easy to use and versatile and compares well to C. difficile culture methods. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Carroll, Karen C
Clostridium difficile (C. difficile) causes 25-30% of cases of antibiotic associated diarrhea and most cases of pseudomembranous colitis. Patients presenting with diarrhea after hospitalization for 3 or more days should be tested for C. difficile. There are many options available for testing, each of which has inherent advantages and disadvantages. Most laboratories perform toxin testing using an enzyme immunoassay method. In general these tests have sensitivities ranging from 60 to 70% and specificities of 98%. When using these methods, symptomatic patients with negative tests should be tested by another more sensitive method. Until recently, cell culture cytotoxicity neutralization assays (CCNAs) were considered the gold standard in the U.S. A two-step algorithm using an EIA for glutamate dehydrogenase detection followed by testing positives using CCNA, offered an improved alternative until the availability of molecular assays. Although early studies that compared the GDH assay to CCNA demonstrated high sensitivity and negative predictive values, more recent comparisons to toxigenic culture and PCR have shown the sensitivity to be in the mid to high 80's. When testing using a sensitive assay, repeat testing is not cost-effective. Outbreaks caused by a toxin variant epidemic strain have renewed interest in bacterial culture. Toxigenic culture has emerged as the new gold standard against which newer assays should be compared. However, there is no agreed upon standard method for culture performance. At least 4 FDA cleared nucleic acid amplification assays are available to clinical laboratories and several of these have been well evaluated in the literature. Because these assays detect a gene that encodes toxin and not the toxin itself it is important that laboratories test only patients with diarrhea. These molecular assays have been shown to be superior to toxin EIAs, CCNA and 2-step algorithms, but not to toxigenic culture. More studies are needed to assess the
Sambol, Susan P.; Merrigan, Michelle M.; Lyerly, David; Gerding, Dale N.; Johnson, Stuart
A toxin variant strain of Clostridium difficile was isolated from two patients with C. difficile-associated disease (CDAD), one of whom died from extensive pseudomembranous colitis. This strain, identified by restriction endonuclease analysis (REA) as type CF2, was not detected by an immunoassay for C. difficile toxin A. Culture supernatants of CF2 failed to elicit significant enterotoxic activity in the rabbit ileal loop assay but did produce atypical cytopathic effects in cell culture assay. Southern hybridization, PCR amplification, and DNA sequence analyses were performed on the toxin A (tcdA) and toxin B (tcdB) genes of type CF2 isolate 5340. Type CF2 5340 tcdA exhibited a 1,821-bp truncation, due to three deletions in the 3′ end of the gene, and a point mutation in the 5′ end of the gene, resulting in a premature stop codon at tcdA position 139. Type CF2 5340 tcdB exhibited multiple nucleotide base substitutions in the 5′ end of the gene compared to tcdB of the standard toxigenic strain VPI 10463. Type CF2 5340 toxin gene nucleotide sequences and deduced amino acid sequences showed a strong resemblance to those of the previously described variant C. difficile strain 1470, a strain reported to have reduced pathogenicity and no association with clinical illness in humans. REA of strain 1470 identified this strain as a distinct type (CF1) within the same REA group as the closely related type CF2. A review of our clinical-isolate collection identified five additional patients infected with type CF2, three of whom had documented CDAD. PCR amplification of the 3′ end of tcdA demonstrated identical 1.8-kb deletions in all seven type CF2 isolates. REA type CF2 is a toxin variant strain of C. difficile that retains the ability to cause disease in humans but is not detected in clinical immunoassays for toxin A. PMID:10992443
Full Text Available A prospective study was conducted to investigate the incidence, clinical profiles and outcome of ICU-onset CDI in a 50-bed medical ICU at a university hospital in China. Stools were collected from patients who developed ICU-onset diarrhea and was screened for tcdA (toxin A gene and tcdB (toxin B gene by PCR. CDI cases were compared with the ICU-onset non-CDI diarrhea cases for demographics, comorbidities, potential risk factors, major laboratory findings and outcomes. Stool samples from CDI cases were subjected to C. difficile culture and C. difficile isolates were screened for tcdA, tcdB and the binary toxin genes (cdtA and cdtB using multiplex PCR. Strain typing of toxigenic C. difficile isolates was performed using multilocus sequence typing. There were 1,277 patients in the ICU during the study period and 124 (9.7% developed ICU-onset diarrhea, of which 31 patients had CDI. The incidence of ICU-onset CDI was 25.2 cases per 10,000 ICU days. ICU-onset CDI cases had similar features with ICU-onset non-CDI diarrhea cases including the use of proton pump inhibitors and antibacterial agents. The crude mortality rate of ICU-onset CDI was 22.6%, but the attributable mortality rate of ICU-onset CDI was only 3.2% here. Toxigenic C. difficile isolates were recovered from 28 out of the 31 patients with CDI. cdtA and cdtB were found in two strains. Seventeen STs including 11 new STs were identified. All of the 11 new STs were single-locus variants of known STs and the 17 STs identified here could be clustered into 3 clades. The incidence of ICU-onset CDI here is similar to those in Europe and North America, suggesting that CDI is likely to be a common problem in China. Toxigenic C. difficile here belonged to a variety of STs, which may represent a significant clonal expansion rather than the true clonal diversity.
Ivarsson, Mattias E; Leroux, Jean-Christophe; Castagner, Bastien
Significant progress has been made by industry and academia in the past two years to address the medical threats posed by Clostridium difficile infection. These developments provide an excellent example of how patient need has driven a surge of innovation in drug discovery. Indeed, only two drugs were approved for the infection in the past 30 years but there are 13 treatment candidates in clinical trials today. What makes the latter number even more remarkable is the diversity in the strategies represented (antibiotics, microbiota supplements, vaccines, antibiotic quenchers and passive immunization). In this review, we provide a snapshot of the current stage of these breakthroughs and argue that there is still room for further innovation in treating C. difficile infection. Copyright © 2014 Elsevier Ltd. All rights reserved.
Nelson, M; Jones, S H; Edwards, C; Ellis, J C
Due to their opportunistic and gregarious nature, gulls may be important reservoirs and vectors for anthropogenically derived fecal pathogens in coastal areas. We used ribotyping, a genotypic bacterial source tracking method, to compare populations of Escherichia coli among herring gulls Larus argentatus, great black-backed gulls L. marinus, wastewater, and landfill trash in New Hampshire and Maine, USA. Concentrations of E. coli in gull feces varied widely among individuals, but were generally high (6.0 x 10(1) to 2.5 x 10(9) g(-1) wet weight). Of 39 E. coli isolates from L. argentatus, 67% had banding patterns that were > or = 90% similar to those from wastewater and trash, whereas only 39% of 36 L. marinus isolates exhibited > or = 90% similarity to these sources. Strains of E. coli from gulls matched (> or = 90% similarity) more strains from wastewater (39% matching) than from trash (15% matching). E. coli isolates from L. marinus feces exhibited a greater diversity of banding patterns than did isolates from L. argentatus. There were more unique E. coli banding patterns in trash samples than in wastewater, and higher diversity indices in the former compared to the latter. These findings suggest that both species of gulls, especially L. argentatus, obtain fecal bacteria from wastewater and landfill trash, which they may transport to recreational beaches and waters. Our results also indicate that E. coli populations may vary widely between gull species, and between the anthropogenic habitats that they frequent, i.e. landfills and wastewater treatment facilities.
Caroff, Daniel A.; Edelstein, Paul H.; Hamilton, Keith; Pegues, David A.
The Bristol stool form scale classifies the relative density of stool samples. In a prospective cohort study, we investigated the associations between stool density, C. difficile assay positivity, hospital-onset C. difficile infection, complications, and severity of C. difficile. We describe associations between the Bristol score, assay positivity, and clinical C. difficile infection.
Caroff, Daniel A; Edelstein, Paul H; Hamilton, Keith; Pegues, David A
The Bristol stool form scale classifies the relative density of stool samples. In a prospective cohort study, we investigated the associations between stool density, C. difficile assay positivity, hospital-onset C. difficile infection, complications, and severity of C. difficile. We describe associations between the Bristol score, assay positivity, and clinical C. difficile infection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
van Nood, Els; Vrieze, Anne; Nieuwdorp, Max; Fuentes, Susana; Zoetendal, Erwin G.; de Vos, Willem M.; Visser, Caroline E.; Kuijper, Ed J.; Bartelsman, Joep F. W. M.; Tijssen, Jan G. P.; Speelman, Peter; Dijkgraaf, Marcel G. W.; Keller, Josbert J.
Recurrent Clostridium difficile infection is difficult to treat, and failure rates for antibiotic therapy are high. We studied the effect of duodenal infusion of donor feces in patients with recurrent C. difficile infection. We randomly assigned patients to receive one of three therapies: an initial
Clostridium difficile: A healthcare-associated infection of unknown significance in adults in sub-Saharan Africa. ... Abstract. Background: Clostridium difficile infection (CDI) causes a high burden of disease in high-resource healthcare systems, with significant morbidity, mortality, and financial implications. CDI is a ...
Ooijevaar, R. E.; van Beurden, Y. H.; Terveer, E. M.; Goorhuis, A.; Bauer, M. P.; Keller, J. J.; Mulder, C. J. J.; Kuijper, E. J.
Clostridium difficile is the leading cause of antibiotic-associated diarrhea, both in healthcare facilities and the community. The recurrence rate of C. difficile infection (CDI) remains high, up to 20%. Since the publication of the ESCMID guidance document on CDI treatment in 2014, new therapeutic
Michael B Francis
Full Text Available Infections caused by Clostridium difficile have increased steadily over the past several years. While studies on C. difficile virulence and physiology have been hindered, in the past, by lack of genetic approaches and suitable animal models, newly developed technologies and animal models allow these processes to be studied in detail. One such advance is the generation of a mouse-model of C. difficile infection. The development of this system is a major step forward in analyzing the genetic requirements for colonization and infection. While important, it is equally as important in understanding what differences exist between mice and humans. One of these differences is the natural bile acid composition. Bile acid-mediated spore germination is an important step in C. difficile colonization. Mice produce several different bile acids that are not found in humans. These muricholic acids have the potential to impact C. difficile spore germination. Here we find that the three muricholic acids (α-muricholic acid, β-muricholic acid and ω-muricholic acid inhibit C. difficile spore germination and can impact the growth of vegetative cells. These results highlight an important difference between humans and mice and may have an impact on C. difficile virulence in the mouse-model of C. difficile infection.
Blixt, Thomas; Gradel, Kim Oren; Homann, Christian
BACKGROUND & AIMS: Nosocomial infection with Clostridium difficile pose a considerable problem despite numerous attempts by health care workers to reduce risk of transmission. Asymptomatic carriers of C difficile might spread their infection to other patients. We investigated the effects of of as......BACKGROUND & AIMS: Nosocomial infection with Clostridium difficile pose a considerable problem despite numerous attempts by health care workers to reduce risk of transmission. Asymptomatic carriers of C difficile might spread their infection to other patients. We investigated the effects...... quartile to 4.2% in the highest quartile of exposed patients (P=.026). Combining the load of exposure to carriers and length of stay seemed to have an additive effect on the risk of contracting C difficile. CONCLUSIONS: In a population-based prospective cohort study in Denmark, we found that asymptomatic...
Löffler, Helga A; Pron, Benedicte; Mouy, Richard; Wulffraat, Nico M; Prieur, Anne-Marie
In adults, reactive arthritis (ReA) following Clostridium difficile-enterocolitis has been documented. In children, only one case of C. difficile-associated ReA has been reported. We now describe two other cases of ReA associated with C. difficile in children. The characteristics of ReA due to C. difficile appear to be similar in adults and children. Both children show polyarthritis after an episode of diarrhoea with positive stool cultures for C. difficile. Arthritis is asymmetrical with a self-limiting course. Nonsteroidal antiinflammatory drug (NSAID) therapy is sufficient. One case is remarkable because of its prolonged course of ReA despite NSAID therapy, and its association with the presence of HLA-B27 antigen.
Several clostridial proteins were detected on the clostridial cell surface by sensitive radioiodination techniques. Two major proteins and six minor proteins comprised the radioiodinated proteins on the clostridial cell surface. Cellular fractionation of surface radiolabeled C. difficile determined that the radioiodinated proteins were found in the cell wall fraction of C. difficile and surprisingly were also present in the clostridial membrane. Furthermore, an interesting phenomenon of disulfide-crosslinking of the cell surface proteins of C. difficile was observed. Disulfide-linked protein complexes were found in both the membrane and cell wall fractions. In addition, the cell surface proteins of C. difficile were found to be released into the culture medium. In attempts to further characterize the clostridial proteins recombinant DNA techniques were employed. In addition, the role of the clostridial cell surface proteins in the interactions of C. difficile with human PMNs was also investigated.
Andersen, Joakim M; Shoup, Madelyn; Robinson, Cathy; Britton, Robert; Olsen, Katharina E P; Barrangou, Rodolphe
Virulent strains of Clostridium difficile have become a global health problem associated with morbidity and mortality. Traditional typing methods do not provide ideal resolution to track outbreak strains, ascertain genetic diversity between isolates, or monitor the phylogeny of this species on a global basis. Here, we investigate the occurrence and diversity of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated genes (cas) in C. difficile to assess the potential of CRISPR-based phylogeny and high-resolution genotyping. A single Type-IB CRISPR-Cas system was identified in 217 analyzed genomes with cas gene clusters present at conserved chromosomal locations, suggesting vertical evolution of the system, assessing a total of 1,865 CRISPR arrays. The CRISPR arrays, markedly enriched (8.5 arrays/genome) compared with other species, occur both at conserved and variable locations across strains, and thus provide a basis for typing based on locus occurrence and spacer polymorphism. Clustering of strains by array composition correlated with sequence type (ST) analysis. Spacer content and polymorphism within conserved CRISPR arrays revealed phylogenetic relationship across clades and within ST. Spacer polymorphisms of conserved arrays were instrumental for differentiating closely related strains, e.g., ST1/RT027/B1 strains and pathogenicity locus encoding ST3/RT001 strains. CRISPR spacers showed sequence similarity to phage sequences, which is consistent with the native role of CRISPR-Cas as adaptive immune systems in bacteria. Overall, CRISPR-Cas sequences constitute a valuable basis for genotyping of C. difficile isolates, provide insights into the micro-evolutionary events that occur between closely related strains, and reflect the evolutionary trajectory of these genomes. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Andersen, Joakim M.; Shoup, Madelyn; Robinson, Cathy; Britton, Robert; Olsen, Katharina E.P.; Barrangou, Rodolphe
Abstract Virulent strains of Clostridium difficile have become a global health problem associated with morbidity and mortality. Traditional typing methods do not provide ideal resolution to track outbreak strains, ascertain genetic diversity between isolates, or monitor the phylogeny of this species on a global basis. Here, we investigate the occurrence and diversity of clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated genes (cas) in C. difficile to assess the potential of CRISPR-based phylogeny and high-resolution genotyping. A single Type-IB CRISPR-Cas system was identified in 217 analyzed genomes with cas gene clusters present at conserved chromosomal locations, suggesting vertical evolution of the system, assessing a total of 1,865 CRISPR arrays. The CRISPR arrays, markedly enriched (8.5 arrays/genome) compared with other species, occur both at conserved and variable locations across strains, and thus provide a basis for typing based on locus occurrence and spacer polymorphism. Clustering of strains by array composition correlated with sequence type (ST) analysis. Spacer content and polymorphism within conserved CRISPR arrays revealed phylogenetic relationship across clades and within ST. Spacer polymorphisms of conserved arrays were instrumental for differentiating closely related strains, e.g., ST1/RT027/B1 strains and pathogenicity locus encoding ST3/RT001 strains. CRISPR spacers showed sequence similarity to phage sequences, which is consistent with the native role of CRISPR-Cas as adaptive immune systems in bacteria. Overall, CRISPR-Cas sequences constitute a valuable basis for genotyping of C. difficile isolates, provide insights into the micro-evolutionary events that occur between closely related strains, and reflect the evolutionary trajectory of these genomes. PMID:27576538
combat zones for C. difficile infections may also be beneficial both for treatment as well as for future research. Further education of healthcare...Ar tillery/Com bat Engineer 4.30 6.04 4.79 18.46 15.92 18.26 13.56 18.07 20.45 23.24 27.78 14.16 Armor/ Mot or Transport 3.30 4.83 18.19 13.55 10.07
Chandrasekaran, Ramyavardhanee; Lacy, D Borden
Clostridium difficile is a bacterial pathogen that is the leading cause of nosocomial antibiotic-associated diarrhea and pseudomembranous colitis worldwide. The incidence, severity, mortality and healthcare costs associated with C. difficile infection (CDI) are rising, making C. difficile a major threat to public health. Traditional treatments for CDI involve use of antibiotics such as metronidazole and vancomycin, but disease recurrence occurs in about 30% of patients, highlighting the need for new therapies. The pathogenesis of C. difficile is primarily mediated by the actions of two large clostridial glucosylating toxins, toxin A (TcdA) and toxin B (TcdB). Some strains produce a third toxin, the binary toxin C. difficile transferase, which can also contribute to C. difficile virulence and disease. These toxins act on the colonic epithelium and immune cells and induce a complex cascade of cellular events that result in fluid secretion, inflammation and tissue damage, which are the hallmark features of the disease. In this review, we summarize our current understanding of the structure and mechanism of action of the C. difficile toxins and their role in disease. Published by Oxford University Press on behalf of FEMS 2017.
Full Text Available Clostridium difficile infection (CDI is a leading cause of antibiotic-associated diarrhea, a major nosocomial complication. The infective form of C. difficile is the spore, a dormant and resistant structure that forms under stress. Although spore germination is the first committed step in CDI onset, the temporal and spatial distribution of ingested C. difficile spores is not clearly understood. We recently reported that CamSA, a synthetic bile salt analog, inhibits C. difficile spore germination in vitro and in vivo. In this study, we took advantage of the anti-germination activity of bile salts to determine the fate of ingested C. difficile spores. We tested four different bile salts for efficacy in preventing CDI. Since CamSA was the only anti-germinant tested able to prevent signs of CDI, we characterized CamSa's in vitro stability, distribution, and cytotoxicity. We report that CamSA is stable to simulated gastrointestinal (GI environments, but will be degraded by members of the natural microbiota found in a healthy gut. Our data suggest that CamSA will not be systemically available, but instead will be localized to the GI tract. Since in vitro pharmacological parameters were acceptable, CamSA was used to probe the mouse model of CDI. By varying the timing of CamSA dosage, we estimated that C. difficile spores germinated and established infection less than 10 hours after ingestion. We also showed that ingested C. difficile spores rapidly transited through the GI tract and accumulated in the colon and cecum of CamSA-treated mice. From there, C. difficile spores were slowly shed over a 96-hour period. To our knowledge, this is the first report of using molecular probes to obtain disease progression information for C. difficile infection.
J.A. Velarde Ruiz-Velasco
hospitalizados. Los hallazgos clínicos y endoscópicos han sido poco estudiados en nuestro país. El objetivo de este estudio es describir estos hallazgos. Material y métodos: Estudio de cohorte prospectivo, se incluyeron pacientes con diarrea hospitalaria asociada a CD, diagnosticada mediante PCR y determinación de cepa hipervirulenta NAP027. Se analizaron los hallazgos clínicos y endoscópicos, así como las variables asociadas a severidad. Resultados: De 127 pacientes con diarrea hospitalaria, se excluyeron 97 por falta de colonoscopia. De los 39 pacientes incluidos, con edad promedio de 48 años, los signos/síntomas más comunes fueron dolor abdominal (49%, moco en heces (41% y sangre en heces (10%; las alteraciones de laboratorio más comunes fueron leucocitosis en el 49%, leucocitos en heces (61% e hipoalbuminemia (67%. El factor de riesgo principal fue el uso de antibiótico en un 62%, más comúnmente la ceftriaxona. La cepa hipervirulenta se presentó en el 54%. Se encontraron anormalidades endoscópicas en el 87%, con colitis seudomembranosa en un 38%, presentándose en colon izquierdo (53% y en derecho (13%. No se encontró asociación entre uso de IBP y diarrea por CD. Se identificó una asociación significativa entre la hipoalbuminemia (< 3.3 g/dL y un mayor riesgo de colitis severa, con un RR de 8.2 (p = 0.008. Conclusiones: Las lesiones de colitis seudomembranosa asociada a CD de cepa hipervirulenta predominan en colon izquierdo. La hipoalbuminemia es un predictor significativo de severidad. Keywords: Clostridium difficile, Pseudomembranous colitis, Colonoscopy, NAP027 strain, Palabras clave: Clostridium difficile, Colitis seudomembranosa, Colonoscopia, Cepa NAP027
Derek M. Tang
Full Text Available Although classically pseudomembranous colitis is caused by Clostridium difficile, it can result from several etiologies. Certain medications, chemical injury, collagenous colitis, inflammatory bowel disease, ischemia, and other infectious pathogens can reportedly cause mucosal injury and subsequent pseudomembrane formation. We present the case of a middle-aged woman with vascular disease who was incorrectly diagnosed with refractory C. difficile infection due to the presence of pseudomembranes. Further imaging, endoscopy, and careful histopathology review revealed chronic ischemia as the cause of her pseudomembranous colitis and diarrhea. This case highlights the need for gastroenterologists to consider non-C. difficile etiologies when diagnosing pseudomembranous colitis.
Maribeth R. Nicholson
Full Text Available Clostridium difficile is a frequent cause of antibiotic-associated diarrhea in adults and older children. However, as many as 80% of infants can be asymptomatically colonized. The reasons for this have not been well established but are believed to be due to differences in toxin receptors or toxin internalization. Determining which children who test positive for C. difficile warrant treatment is exceedingly difficult, especially in the setting of increased rates of detection and the rising risk of disease in children lacking classic risk factors for C. difficile.
Vogel, Birte Fonnesbech; Jørgensen, K.; Christensen, H.
methods. Numerical analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell protein and ribotyping patterns showed that the strains were separated into two distinct clusters with 56% +/- 10% and 40% +/- 14% similarity for whole- cell protein profiling and ribotyping...... by 16S rRNA gene sequence analysis. It is concluded that the isolates must be considered two different species, S. alga and S. putrefaciens, and that most mesophilic isolates formerly identified as S. putrefaciens belong to S. alga. The ecological role and potential pathogenicity of S. alga can...
Full Text Available The aim of the present study was to determine whether Clostridium difficile was present in uncooked retail ground beef and ground pork products sold in Winnipeg, Manitoba. Using an alcohol treatment protocol and inoculation of cultures on C difficile Moxalactam Norfloxacin (CDMN, toxigenic C difficile was found in 6.3% of 48 meat samples. The C difficile isolates belonged to different pulsotypes, all of which had been previously isolated from the stool of Manitoba patients with C difficile disease. Because cooking of meat will not eradicate C difficile spores, this raises a concern regarding potential foodborne transmissibility of this organism.
Finegold, Sydney M; Summanen, Paula H; Corbett, Karen; Downes, Julia; Henning, Susanne M; Li, Zhaoping
To determine the possible utility of pomegranate extract in the management or prevention of Clostridium difficile infections or colonization. The activity of pomegranate was tested against 29 clinical C. difficile isolates using the Clinical and Laboratory Standards Institute-approved agar dilution technique. Total phenolics content of the pomegranate extract was determined by Folin-Ciocalteau colorimetric method and final concentrations of 6.25 to 400 μg/mL gallic acid equivalent were achieved in the agar. All strains had MICs at 12.5 to 25 mg/mL gallic acid equivalent range. Our results suggest antimicrobial in vitro activity for pomegranate extract against toxigenic C. difficile. Pomegranate extract may be a useful contributor to the management and prevention of C. difficile disease or colonization. Copyright © 2014 Elsevier Inc. All rights reserved.
Tvede, M; Tinggaard, M; Helms, M
Clostridium difficile infection is one of the most common nosocomial infections. Among other alternatives to standard treatment with vancomycin for recurrent infection are faecal microbiota transplantation and rectal bacteriotherapy with a fixed mixture of intestinal bacterial strains isolated from...
Rodriguez, C; Taminiau, B; Van Broeck, J; Delmée, M; Daube, G
Zoonoses are infections or diseases that can be transmitted between animals and humans through direct contact, close proximity or the environment. Clostridium difficile is ubiquitous in the environment, and the bacterium is able to colonise the intestinal tract of both animals and humans. Since domestic and food animals frequently test positive for toxigenic C. difficile, even without showing any signs of disease, it seems plausible that C. difficile could be zoonotic. Therefore, animals could play an essential role as carriers of the bacterium. In addition, the presence of the spores in different meats, fish, fruits and vegetables suggests a risk of foodborne transmission. This review summarises the current available data on C. difficile in animals and foods, from when the bacterium was first described up to the present.
Full Text Available Clostridium difficile colitis is a common infection that can be difficult to resolve and may result in recurrent infections. Reactive arthritis is a rare presentation of this disease and its treatment is not well differentiated in the literature. We describe a case of reactive arthritis occurring in a patient with a history of recurrent Clostridium difficile colitis while currently receiving a taper of oral vancomycin. His arthritis symptoms resolved with corticosteroids and continued treatment with anticlostridial antibiotics.
Könönen, Eija; Rasinperä, Marja; Virolainen, Anni; Mentula, Silja; Lyytikäinen, Outi
Due to increased interest directed to Clostridium difficile-associated infections, a questionnaire survey of laboratory diagnostics of toxin-producing C. difficile was conducted in Finland in June 2006. Different aspects pertaining to C. difficile diagnosis, such as requests and criteria used for testing, methods used for its detection, yearly changes in diagnostics since 1996, and the total number of investigations positive for C. difficile in 2005, were asked in the questionnaire, which was sent to 32 clinical microbiology laboratories, including all hospital-affiliated and the relevant private clinical microbiology laboratories in Finland. The situation was updated by phone and email correspondence in September 2008. In June 2006, 28 (88%) laboratories responded to the questionnaire survey; 24 of them reported routinely testing requested stool specimens for C. difficile. Main laboratory methods included toxin detection (21/24; 88%) and/or anaerobic culture (19/24; 79%). In June 2006, 18 (86%) of the 21 laboratories detecting toxins directly from feces, from the isolate, or both used methods for both toxin A (TcdA) and B (TcdB), whereas only one laboratory did so in 1996. By September 2008, all of the 23 laboratories performing diagnostics for C. difficile used methods for both TcdA and TcdB. In 2006, the number of specimens processed per 100,000 population varied remarkably between different hospital districts. In conclusion, culturing C. difficile is common and there has been a favorable shift in toxin detection practice in Finnish clinical microbiology laboratories. However, the variability in diagnostic activity reported in 2006 creates a challenge for national monitoring of the epidemiology of C. difficile and related diseases.
C. difficile is recognised as the main cause for colitis in hospitalised patients which are treated with antibiotics, chemotherapics or other drugs that disturb intestinal microbiota. Thus, a rapid and correct diagnostic of Clostridium difficile infections is essential for preventing nosocomial infection spread. Empiric therapy, regardless of the laboratory investigation results, is inadequate, especially in epidemic situations, as not all the cases of diarrhoea are due to C. difficile infection. Other risk factors for CDAD (Clostridiumn difficile Associated Diseases might be: prolonged hospitalization or residency in an asylum, age, existence of a severe chronic disease in the background nasogastric intubation, anti-ulcer drugs, at less extent gastrointestinal surgery, other immunosuppresive compounds etc. In our country, C. difficile infection is rather frequent in adults, though it is not always reported by clinicians. The circulation of endemic rybotype 027 in Romania is not well documented, the rybotype being extremely virulent and spread in other European countries. Hence the importance of extending the diagnostic capacity of C. difficile infection in order to allow detection of this rybotype among the strains isolated in our country.
Full Text Available La cardiomyopathie hypertrophique neonatale est une entite rare, heterogene regroupant plusieurs formes cliniques et donc de diagnostic etiologique difficile. Nous rapportons l�observation d�un nouveau ne issu d�une grossesse gemellaire, ayant presente a la naissance un tableau d�insuffisance cardiaque, l�echocardiographie avait conclut a une cardiomyopathie hypertrophique obstructive. Le bilan etiologique etait negatif notamment une mere non diabetique. L�evolution etait favorable avec regression de l�hypertrophie 2 semaines apres la naissance. L�etiologie finalement suggeree etait une cardiomyopathie secondaire a l�injection antenatale de corticoides dans le but d�accelerer la maturation pulmonaire. L�etablissement par les societes savantes d�un consensus de bilan etiologique minimal standard selon une chronologie bien determinee serait d�un grand apport dans la prise en charge de cette anomalie.
Fukugaiti, Márcia H; Ignacio, Aline; Fernandes, Miriam R; Ribeiro Júnior, Ulysses; Nakano, Viviane; Avila-Campos, Mario J
Colorectal carcinoma is considered the fourth leading cause of cancer deaths worldwide. Several microorganisms have been associated with carcinogenesis, including Enterococcus spp., Helicobacter pylori, enterotoxigenic Bacteroides fragilis, pathogenic E. coli strains and oral Fusobacterium. Here we qualitatively and quantitatively evaluated the presence of oral and intestinal microorganisms in the fecal microbiota of colorectal cancer patients and healthy controls. Seventeen patients (between 49 and 70 years-old) visiting the Cancer Institute of the Sao Paulo State were selected, 7 of whom were diagnosed with colorectal carcinoma. Bacterial detection was performed by qRT-PCR. Although all of the tested bacteria were detected in the majority of the fecal samples, quantitative differences between the Cancer Group and healthy controls were detected only for F. nucleatum and C. difficile. The three tested oral microorganisms were frequently observed, suggesting a need for furthers studies into a potential role for these bacteria during colorectal carcinoma pathogenesis. Despite the small number of patients included in this study, we were able to detect significantly more F. nucleatum and C. difficile in the Cancer Group patients compared to healthy controls, suggesting a possible role of these bacteria in colon carcinogenesis. This finding should be considered when screening for colorectal cancer.
Crobach, Monique J T; Baktash, Amoe; Duszenko, Nikolas; Kuijper, Ed J
Diagnosis of Clostridium difficile infection (CDI) can be challenging. First of all, there has been debate on which of the two reference assays, cell cytotoxicity neutralization assay (CCNA) or toxigenic culture (TC) should be considered the gold standard for CDI detection. Although the CCNA suffers most from suboptimal storage conditions and subsequent toxin degradation, TC is reported to falsely increase CDI detection rates as it cannot differentiate CDI patients from patients asymptomatically colonised by toxigenic C. difficile. Several rapid assays are available for CDI detection and fall into three broad categories: (1) enzyme immunoassays for glutamate dehydrogenase, (2) enzyme immunoassays for toxins A/B and (3) nucleic acid amplification tests detecting toxin genes. All three categories have their own limitations, being suboptimal specificity and/or sensitivity or the inability to discern colonised patients from CDI patients. In light of these limitations, multi-step algorithmic testing has now been advocated by international guidelines in order to optimize diagnostic accuracy. Despite these recommendations, testing methods between hospitals vary widely, which impacts CDI incidence rates. CDI incidence rates are also influenced by sample selection criteria, as several studies have shown that if not all unformed stool samples are tested for CDI, many cases may be missed due to an absence of clinical suspicion. Since methods for diagnosing CDI remain imperfect, there has been a growing interest in alternative testing strategies like faecal biomarkers, immune modulating interleukins, cytokines and imaging methods. At the moment, these alternative methods might play an adjunctive role, but they are not suitable to replace conventional CDI testing strategies.
Olsen, J. E.; Skov, M. N.; Angen, Øystein
The genomic relationship between isolates representing 17 definitive phage types (DTs) of Salmonella enterica subsp. enterica serotype typhimurium (S. typhimurium) were analysed using three different typing methods: IS200 typing using the restriction enzymes EcoRI and Pvull, ribotyping using Smal...
Aarestrup, Frank Møller
A total of 41 Staphylococcus intermedius isolates were isolated from skin of healthy members of six phylogenetic groups within the Canoidea (the dog family, skunk subfamily, weasel subfamily, racoon family, red panda and bear family) of different geographical origin and compared by EcoRI ribotyping...
Full Text Available Abstract Background Clostridium difficile ribotype 027 has become increasingly prevalent in European countries. The clinical picture varies from self-limiting diarrhea to pseudomembranous colitis with toxic megacolon and ultimately death. Use of antibiotics is the principal risk factor; others include comorbidity, advanced age and hospitalization. However even with extensive knowledge of risk factors, it remains difficult to define “minimum risk,” as illustrated by the following case. Case presentation An 80-year-old Danish man in good health was hospitalized for a penetrating knee injury. He received 5 days of intravenous cefuroxime after surgical revision and was discharged with oral cephalexin. Post-discharge he suffered from abdominal discomfort and was readmitted with ileus 4 days after discharge, i.e. 10 days after initiation of antibiotic treatment. His condition deteriorated, and pseudomembranous colitis was diagnosed. Due to lack of response to vancomycin and metronidazole, a total colectomy was performed. Stool cultures were positive for CD 027. Conclusion Short-term use of cephalosporins may have induced CD 027 infection, and the patient’s age was the only identifiable risk factor for the fulminant course. Thus, even short-term prophylactic treatment with cephalosporins cannot be considered entirely safe.
Detection of enterotoxin A and cytotoxin B, and isolation of Clostridium difficile in piglets in Minas Gerais, Brazil Detecção da enterotoxina A e citotoxina B e isolamento de Clostridium difficile em leitões em Minas Gerais, Brasil
Rodrigo Otávio Silveira Silva
Full Text Available Clostridium difficile has emerged as a major cause of neonatal colitis in piglets, displacing classic bacterial pathogens. However, there is no information regarding the distribution of this microorganism in pig farms in Brazil. In the present study, the presence of toxins A/B and of C. difficile strains in stool samples from 60 diarrheic or non-diarrheic newborn piglets (one to seven days old, from 15 different farms, was studied. The presence of toxins A/B was detected by ELISA and PCR was used to identify toxin A, toxin B and binary toxin gene in each isolated strain. C. difficile A/B toxins were detected in ten samples (16.7%. Of these, seven were from diarrheic and three were from non-diarrheic piglets. C. difficile was recovered from 12 out of 60 (20% fecal samples. Of those, three strains were non-toxigenic (A-B- and nine were toxigenic. Of the nine toxigenic strains, four were A+B+ strains and five were A-B+ strains. The presence of binary toxin observed in the present study was much higher (50% than in previously reported studies. All three non-toxigenic strains were isolated from otherwise healthy piglets. The results suggest the occurrence of neonatal diarrhea by C. difficile in farms in Brazil.Clostridium difficile tem sido relatado como o principal causador de colite neonatal em suínos. Apesar da crescente importância deste agente, não há dados sobre infecções causadas por C. difficile em suínos no Brasil. O objetivo do presente estudo foi detectar as toxinas A/B e isolar C. difficile a partir de 60 amostras de fezes de leitões diarreicos ou apararentemente saudáveis, com no máximo sete dias de vida, e oriundos de 15 granjas diferentes. As toxinas A/B foram detectadas por ELISA e uma PCR multiplex foi utilizada para detecção dos genes responsáveis pela codificação das toxinas A, B e toxina binária. As toxinas A/B de C. difficile foram detectadas em dez amostras de fezes (16.7%. Dessas, sete eram de animais diarreicos
Meloni, Domenico; Galluzzo, Pietro; Mureddu, Anna; Piras, Francesca; Griffiths, Mansel; Mazzette, Rina
The aims of the present study were: (a) to investigate the prevalence and the enumeration of Listeria monocytogenes in 200 samples of ready to eat (RTE) foods of animal and vegetal origin collected from different outlets and processing plants in Sardinia; (b) to characterize the isolates by phenotypical and molecular methods; (c) to analyze a subset of 42 L. monocytogenes by automated EcoRI ribotyping in order to predict the strain's potential virulence for humans. The strains were isolated from: smoked fish products, cooked marinated products, meat products and pre-packaged mixed vegetable salads. Of the samples tested, 22% were positive for Listeria spp. The prevalence of L. monocytogenes was 9.5%, while the level of L. monocytogenes in the positive samples was 93%), belonging to 17 different DuPont Identification Library Codes (DUP-IDs) clones. The Simpson's numerical index of discrimination was 0.911. Cluster analysis pointed out a high similarity among strains isolated from meat, fish, and vegetables of different origin. These results confirmed the existence of a widespread population of L. monocytogenes, characterized by highly related strains existing in different geographical areas. 65% of these strains belonged to lineage II (serotypes 1/2a and 1/2c), subtypes known to be associated with sporadic human listeriosis outbreaks. The remaining 35% of the isolates (serotypes 1/2b, 3b and 4b) were allocated to lineage I and belong to distinct clonal groups (DUP-ID 1038 and 1042), which again have been associated with several outbreaks of human listeriosis. Neither atypical profiles nor lineage III strains were found. EcoRI ribotyping was confirmed as a rapid and reliable method for L. monocytogenes typing, providing useful data for epidemiologic and clonality surveys of L. monocytogenes strains isolated from RTE foods.
Silva, Rodrigo Otávio Silveira; D'elia, Mirella Lauria; de Magalhães Soares, Danielle Ferreira; Cavalcanti, Álvaro Roberto; Leal, Rodrigo Costa; Cavalcanti, Guilherme; Pereira, Pedro Lúcio Lithg; Lobato, Francisco Carlos Faria
The aim of this study is to report a case of Clostridium difficile-associated diarrhea in an ocelot (Leopardus pardalis) in the state of Mato Grosso do Sul, Brazil. The animal, a 24-month-old male, was referred to the Centro de Reabilitação de Animais Silvestres (CRAS) with a history of having been run over and tibia and fibula fractures. After a surgery to repair the fractures, the ocelot underwent antibiotic therapy with two doses of sodium cefovecin, during which he presented with diarrhea. A stool sample was positive for A/B toxins by a cytotoxicity assay, and a toxigenic strain of C. difficile was isolated. No other enteropathogens were detected. The association between the history, clinical signs and laboratory exams confirmed the diagnosis of C. difficile-associated diarrhea. The present report confirms C. difficile as a potential pathogen for wild felids and suggests that the C. difficile-associated diarrhea should be considered in diarrhea cases, especially when the clinical signs began after antimicrobial use. Copyright © 2013 Elsevier Ltd. All rights reserved.
Chumbler, Nicole M.; Rutherford, Stacey A.; Zhang, Zhifen; Farrow, Melissa A.; Lisher, John P.; Farquhar, Erik; Giedroc, David P.; Spiller, Benjamin W.; Melnyk, Roman A.; Lacy, D. Borden
Clostridium difficile infection is the leading cause of hospital-acquired diarrhoea and pseudomembranous colitis. Disease is mediated by the actions of two toxins, TcdA and TcdB, which cause the diarrhoea, as well as inflammation and necrosis within the colon. The toxins are large (308 and 270 kDa, respectively), homologous (47% amino acid identity) glucosyltransferases that target small GTPases within the host. The multidomain toxins enter cells by receptor-mediated endocytosis and, upon exposure to the low pH of the endosome, insert into and deliver two enzymatic domains across the membrane. Eukaryotic inositol-hexakisphosphate (InsP6) binds an autoprocessing domain to activate a proteolysis event that releases the N-terminal glucosyltransferase domain into the cytosol. Here, we report the crystal structure of a 1,832-amino-acid fragment of TcdA (TcdA1832), which reveals a requirement for zinc in the mechanism of toxin autoprocessing and an extended delivery domain that serves as a scaffold for the hydrophobic α-helices involved in pH-dependent pore formation. A surface loop of the delivery domain whose sequence is strictly conserved among all large clostridial toxins is shown to be functionally important, and is highlighted for future efforts in the development of vaccines and novel therapeutics.
Peng, Zhong; Addisu, Anteneh; Alrabaa, Sally; Sun, Xingmin
Clostridium difficile is an important cause of nosocomial acquired antibiotic-associated diarrhea causing an estimated 453,000 cases with 29,000 deaths yearly in the U.S. Both antibiotic resistance and toxin expression of C. difficile correlate with the severity of C. difficile infection (CDI). In this report, a total of 139 C. difficile isolates from patients diagnosed with CDI in Tampa General Hospital (Florida) in 2016 were studied for antibiotic resistance profiles of 12 types of antibiotics and toxin production. Antibiotic resistance determined by broth microdilution method showed that strains resistant to multi-antibiotics are common. Six strains (4.32%) showed resistance to six types of antibiotics. Twenty strains (14.39%) showed resistance to five types of antibiotics. Seventeen strains (12.24%) showed resistance to four types of antibiotics. Thirty-nine strains (28.06%) showed resistance to three types of antibiotic. Thirty-four strains (24.46%) showed resistance to two types of antibiotics. While, all isolates were susceptible to metronidazole, and rifaximin, we found that one isolate (0.72%) displayed resistance to vancomycin (MIC ≥ 8 μg/ml), and another one was resistant to fidaxomicin (MIC >1 μg/ml). The percentage of isolates resistant to cefoxitin, ceftriaxone, chloramphenicol, ampicillin, clindamycin, erythromycin, gatifloxacin, and moxifloxacin was 75.54, 10.79, 5.76, 67.63, 82.70, 45.32, 28.06, and 28.78%, respectively. Toxin profiling by PCR showed the isolates include 101 (72.66%) A+B+CDT-strains, 23 (16.55%) A+B+CDT+ strains, 3 (2.16%) A-B+CDT+ strains, 1 (0.72%) A-B+CDT-strains, and 11 (7.91%) A-B-CDT-strains. Toxin production determined by ELISA using supernatants of bacterial culture harvested at 12, 24, 48, and 72 h of post inoculation (hpi) showed that the toxins were mainly produced between 48 and 72 hpi, and toxin B (TcdB) was produced faster than toxin A (TcdA) during the experimental time (72 hpi). In addition, the binary
Full Text Available Abstract Background Exposure to antimicrobials is the major risk factor associated with Clostridium difficile infection (CDI. Paradoxically, treatment of CDI with antimicrobials remains the preferred option. To date, only three studies have investigated the antimicrobial susceptibility of C. difficile from Thailand, two of which were published in the 1990s. This study aimed to investigate the contemporary antibiotic susceptibility of C. difficile isolated from patients in Thailand. Methods A collection of 105 C. difficile isolated from inpatients admitted at Siriraj Hospital in Bangkok in 2015 was tested for their susceptibility to nine antimicrobials via an agar incorporation method. Results All isolates were susceptible to vancomycin, metronidazole, amoxicillin/clavulanate and meropenem. Resistance to clindamycin, erythromycin and moxifloxacin was observed in 73.3%, 35.2% and 21.0% of the isolates, respectively. The in vitro activity of fidaxomicin (MIC50/MIC90 0.06/0.25 mg/L was superior to first-line therapies vancomycin (MIC50/MIC90 1/2 mg/L and metronidazole (MIC50/MIC90 0.25/0.25 mg/L. Rifaximin exhibited potent activity against 85.7% of the isolates (MIC ≤0.03 mg/L, and its MIC50 (0.015 mg/L was the lowest among all antimicrobials tested. The prevalence of multi-drug resistant C. difficile, defined by resistance to ≥3 antimicrobials, was 21.9% (23/105. Conclusions A high level of resistance against multiple classes of antimicrobial was observed, emphasising the need for enhanced antimicrobial stewardship and educational programmes to effectively disseminate information regarding C. difficile awareness and appropriate use of antimicrobials to healthcare workers and the general public.
Vaustat, Daniela; Rollet, Raquel
Clostridioides difficile is the main etiological agent of diarrhea associated with health care, it produces toxins and glutamate dehydrogenase (GDH), an enzyme that is highly conserved in this species. Rapid diagnosis and effective treatment produce prompt improvement of the patient and subsequent control of the microorganism spread. There are several techniques whose results are interpreted in the context of algorithms. However, the optimal diagnostic method is yet unknown. The performance of GDH as a screening test for the diagnosis of C. difficile diarrhea was assessed. Six hundred and fifteen stool samples were studied. The presence of GDH and toxins presence was determined by TECHLAB ® C. DIFF QUIK-CHEK COMPLETE and the samples were cultured for the search of C. difficile. The values of sensitivity, specificity, PPV and NPV were calculated with a p value of 0.05 or less. GDH was detected in 266 samples (43.25%), with a sensitivity of 100% and specificity of 87.10%, IC95: 84.58-91.42; toxin/s were detected in 218 (35.45%) and C. difficile developed in 235 cultures (38.21%). From 48 samples with positive GDH and negative toxin/s, 15 toxigenic and 2 non-toxigenic isolates were obtained, the remaining 31 samples were negative for C. difficile. All GDH-negative samples were negative for toxins or culture, therefore, GDH NPV was 100%, while PPV was 81.9%. We conclude that GDH is a suitable screening test for the diagnostic algorithm of C. difficile diarrhea. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
Søes, Lillian Marie; Holt, H M; Böttiger, B
SUMMARY To identify risk factors for Clostridium difficile infection (CDI) in Danish patients consulting general practice with gastrointestinal symptoms, a prospective matched case-control study was performed; cases (N = 259) had positive cultures for toxigenic C. difficile and controls (N = 455......) negative cultures. Data were analysed by conditional logistic regression. In patients aged ⩾2 years (138 cases), hospitalization [odds ratio (OR) 8·4, 95% confidence interval (CI) 3·1-23], consumption of beef (OR 5·5, 95% CI 2·0-15), phenoxymethylpenicillin (OR 15, 95% CI 2·7-82), dicloxacillin (OR 27, 95...
Martin-Verstraete, Isabelle; Peltier, Johann; Dupuy, Bruno
The pathogenic clostridia cause many human and animal diseases, which typically arise as a consequence of the production of potent exotoxins. Among the enterotoxic clostridia, Clostridium difficile is the main causative agent of nosocomial intestinal infections in adults with a compromised gut microbiota caused by antibiotic treatment. The symptoms of C. difficile infection are essentially caused by the production of two exotoxins: TcdA and TcdB. Moreover, for severe forms of disease, the spectrum of diseases caused by C. difficile has also been correlated to the levels of toxins that are produced during host infection. This observation strengthened the idea that the regulation of toxin synthesis is an important part of C. difficile pathogenesis. This review summarizes our current knowledge about the regulators and sigma factors that have been reported to control toxin gene expression in response to several environmental signals and stresses, including the availability of certain carbon sources and amino acids, or to signaling molecules, such as the autoinducing peptides of quorum sensing systems. The overlapping regulation of key metabolic pathways and toxin synthesis strongly suggests that toxin production is a complex response that is triggered by bacteria in response to particular states of nutrient availability during infection. PMID:27187475
Chmielewska, M; Zycinska, K; Lenartowicz, B; Hadzik-Błaszczyk, M; Cieplak, M; Kur, Z; Wardyn, K A
One of the most common gastrointestinal infection after the antibiotic treatment of community or nosocomial pneumonia is caused by the anaerobic spore Clostridium difficile (C. difficile). The aim of this study was to retrospectively assess mortality due to C. difficile infection (CDI) in patients treated for pneumonia. We identified 94 cases of post-pneumonia CDI out of the 217 patients with CDI. The mortality issue was addressed by creating a mortality risk models using logistic regression and multivariate fractional polynomial analysis. The patients' demographics, clinical features, and laboratory results were taken into consideration. To estimate the influence of the preceding respiratory infection, a pneumonia severity scale was included in the analysis. The analysis showed two statistically significant and clinically relevant mortality models. The model with the highest prognostic strength entailed age, leukocyte count, serum creatinine and urea concentration, hematocrit, coexisting neoplasia or chronic obstructive pulmonary disease. In conclusion, we report on two prognostic models, based on clinically relevant factors, which can be of help in predicting mortality risk in C. difficile infection, secondary to the antibiotic treatment of pneumonia. These models could be useful in preventive tailoring of individual therapy.
Full Text Available The pathogenic clostridia cause many human and animal diseases, which typically arise as a consequence of the production of potent exotoxins. Among the enterotoxic clostridia, Clostridium difficile is the main causative agent of nosocomial intestinal infections in adults with a compromised gut microbiota caused by antibiotic treatment. The symptoms of C. difficile infection are essentially caused by the production of two exotoxins: TcdA and TcdB. Moreover, for severe forms of disease, the spectrum of diseases caused by C. difficile has also been correlated to the levels of toxins that are produced during host infection. This observation strengthened the idea that the regulation of toxin synthesis is an important part of C. difficile pathogenesis. This review summarizes our current knowledge about the regulators and sigma factors that have been reported to control toxin gene expression in response to several environmental signals and stresses, including the availability of certain carbon sources and amino acids, or to signaling molecules, such as the autoinducing peptides of quorum sensing systems. The overlapping regulation of key metabolic pathways and toxin synthesis strongly suggests that toxin production is a complex response that is triggered by bacteria in response to particular states of nutrient availability during infection.
Increased incidence of Clostridium difficile infection (CDI) among in-patients is associated with significant increased mortality, morbidity, and stay in the hospitals. This has occurred despite heightened awareness of the risks of broad-spectrum antibiotics, overall reduction in antibiotic use and increased focus on hospital hygiene. So though the main risk factor for CDI is use of broad-spectrum antibiotics, the use of proton pump inhibitors (PPIs) as a novel potential contributor has been implicated, because of their ability to substantially reduce gastric acid secretion which is an important host defense mechanism in suppressing the ingested C. difficile or its spores. Antibiotic disruption of the normal intestinal flora and reduced gastric acidity have been suggested as the risk factors for C. difficile-associated diarrhea (CDAD). Based on such assumptions the use of PPIs may be associated with an increased risk of CDAD. While a definite association between PPI use and CDAD has not yet been confirmed, the possibility and such an association however cannot be ruled out at present. Thus among the identified risk factors, the use of PPI is important, previously unrecognized and modifiable risk factors whose use should be carefully evaluated among hospital in-patients receiving antibiotics, especially in those with a diagnosis of C. difficile diarrhea.
Full Text Available Fredy Chaparro-Rojas, Kathleen M MullaneDepartment of Medicine, Section of Infectious Diseases, University of Chicago, Chicago, IL, USAAbstract: The epidemiology of Clostridium difficile infections (CDI has evolved during the last decades, with an increase in the reported incidence, severity of cases, and rate of mortality and relapses. These increases have primarily affected some special populations including the elderly, patients requiring concomitant antibiotic therapy, patients with renal failure, and patients with cancer. Until recently, the treatment of CDI was limited to either metronidazole or vancomycin. New therapeutic options have emerged to address the shortcomings of current antibiotic therapy. Fidaxomicin stands out as the first-in-class oral macrocyclic antibiotic with targeted activity against C. difficile and minimal collateral damage on the normal colonic flora. Fidaxomicin has demonstrated performance not inferior to what is considered the “gold standard” available therapy for CDI, vancomycin, in two separate Phase III clinical trials, but with significant advantages, including fewer recurrences and higher rates of sustained clinical cures. Fidaxomicin constitutes an important development in targeted antibiotic therapy for CDI and must be considered as a first-line agent for patients with risk factors known to portend relapse and severe infection.Keywords: fidaxomicin, Clostridium difficile-associated diarrhea, CDAD, Clostridium difficile infection (CDI, vancomycin, metronidazole
Clostridium difficileis one of the most important causes of diarrhoea especially following antibiotic course. Elderly population is more susceptible and results in significant mortality and morbidity. We audited twenty four cases of Clostridium difficile in our hospital over duration of three months. We looked into the demographic
Hogendorf, Wouter Frederik Johan; Gisch, Nicolas; Schwudke, Dominik
The emergence of hypervirulent resistant strains have made Clostridium difficile a notorious nosocomial pathogen and has resulted in a renewed interest in preventive strategies, such as vaccines based on (synthetic) cell wall antigens. Recently, the structure of the lipoteichoic acid (LTA...
Tsapepas, Demetra S; Martin, Spencer T; Miao, Jennifer; Shah, Shreya A; Scheffert, Jenna; Fester, Keith; Ma, Karlene; Lat, Asma; Egan, Ron; McKeen, Jaclyn T
Clostridium difficile is a bacterial enteric pathogen, which causes clinical disease among solid organ transplant (SOT) recipients. This large, single-center, retrospective study describes incidence, demographics, and impact of C. difficile infection (CDI) among adult SOT recipients, cardiac (n=5), lung (n=14), liver (n=9), renal (n=26), and multiorgan (n=9) patients transplanted and diagnosed with CDI (geneB PCR) between 9/2009 and 12/2012. The overall incidence of CDI in our population during the 40-month period of study was 4%. CDI incidence among cardiac, lung, liver, and renal transplant recipients was 1.9%, 7%, 2.7%, and 3.2%, respectively (P=0.03 between organ-types). Median time from transplant to CDI for all was 51 (14-249) days, with liver recipients having the shortest time to infection, median 36 (15-101) days, and lung recipients having a longer time to infection, median 136 (29-611) days. Antibiotic exposure within 3 months of CDI was evident in 45 of the 63 (71%) patients in this study, 80%, 79%, 100%, 58%, and 67% of cardiac, lung, liver, renal, and multiorgan transplant recipients, respectively. Most patients (83%) were hospitalized within the 3 months preceding CDI. Recipients were followed for a median time of 23 (16-31) months; at the time of last follow-up, 83% of allografts were functioning, and 86% of patients were alive. One death and 1 graft failure were causally related to CDI. CDI had an overall incidence of 4%; clinicians should have heightened awareness for CDI, especially among patients receiving antibiotics, with increased monitoring and aggressive management of CDI. Copyright © 2015 Elsevier Inc. All rights reserved.
Barkin, Jodie A; Sussman, Daniel A; Fifadara, Nimita; Barkin, Jamie S
Clostridium difficile (CD) infection (CDI) causes marked morbidity and mortality, accounting for large healthcare expenditures annually. Current CDI treatment guidelines focus on clinical markers of patient severity to determine the preferred antibiotic regimen of metronidazole versus vancomycin. The antimicrobial resistance patterns for patients with CD are currently unknown. The aim of this study was to define the antimicrobial resistance patterns for CD. This study included all patients with stools sent for CD testing to a private laboratory (DRG Laboratory, Alpharetta, Georgia) in a 6-month period from across the USA. Patient data was de-identified, with only age, gender, and zip-code available per laboratory protocol. All samples underwent PCR testing followed by hybridization for CD toxin regions A and B. Only patients with CD-positive PCR were analyzed. Antimicrobial resistance testing using stool genomic DNA evaluated presence of imidazole- and vancomycin-resistant genes using multiplex PCR gene detection. Of 2743, 288 (10.5%) stool samples were positive for CD. Six were excluded per protocol. Of 282, 193 (69.4%) were women, and average age was 49.4 ± 18.7 years. Of 282, 62 were PCR positive for toxins A and B, 160 for toxin A positive alone, and 60 for toxin B positive alone. Antimicrobial resistance testing revealed 134/282 (47.5%) patients resistant to imidazole, 17 (6.1%) resistant to vancomycin, and 9 (3.2%) resistant to imidazole and vancomycin. CD-positive patients with presence of imidazole-resistant genes from stool DNA extract was a common phenomenon, while vancomycin resistance was uncommon. Similar to treatment of other infections, antimicrobial resistance testing should play a role in CDI clinical decision-making algorithms to enable more expedited and cost-effective delivery of patient care.
In the past decade Clostridium difficile has become a bacterial pathogen of global significance. Epidemic strains have spread throughout hospitals, while community acquired infections and other sources ensure a constant inoculation of spores into hospitals. In response to the increasing medical burden, a new C. difficile antibiotic, fidaxomicin, was approved in 2011 for the treatment of C. difficile-associated diarrhea. Rudimentary fecal transplants are also being trialed as effective treatments. Despite these advances, therapies that are more effective against C. difficile spores and less damaging to the resident gastrointestinal microbiome and that reduce recurrent disease are still desperately needed. However, bringing a new treatment for C. difficile infection to market involves particular challenges. This review covers the current drug discovery pipeline, including both small molecule and biologic therapies, and highlights the challenges associated with in vitro and in vivo models of C. difficile infection for drug screening and lead optimization. PMID:25760275
Priscilla A. Johanesen
Full Text Available Clostridium difficile is well recognized as the leading cause of antibiotic-associated diarrhea, having a significant impact in both health-care and community settings. Central to predisposition to C. difficile infection is disruption of the gut microbiome by antibiotics. Being a Gram-positive anaerobe, C. difficile is intrinsically resistant to a number of antibiotics. Mobile elements encoding antibiotic resistance determinants have also been characterized in this pathogen. While resistance to antibiotics currently used to treat C. difficile infection has not yet been detected, it may be only a matter of time before this occurs, as has been seen with other bacterial pathogens. This review will discuss C. difficile disease pathogenesis, the impact of antibiotic use on inducing disease susceptibility, and the role of antibiotic resistance and mobile elements in C. difficile epidemiology.
Kundrapu, Sirisha; Sunkesula, Venkata C K; Jury, Lucy A; Cadnum, Jennifer L; Nerandzic, Michelle M; Musuuza, Jackson S; Sethi, Ajay K; Donskey, Curtis J
Systemic antibiotics vary widely in in vitro activity against Clostridium difficile. Some agents with activity against C. difficile (e.g., piperacillin/tazobactam) inhibit establishment of colonization in mice. We tested the hypothesis that piperacillin/tazobactam and other agents with activity against C. difficile achieve sufficient concentrations in the intestinal tract to inhibit colonization in patients. Point-prevalence culture surveys were conducted to compare the frequency of asymptomatic rectal carriage of toxigenic C. difficile among patients receiving piperacillin/tazobactam or other inhibitory antibiotics (e.g. ampicillin, linezolid, carbapenems) versus antibiotics lacking activity against C. difficile (e.g., cephalosporins, ciprofloxacin). For a subset of patients, in vitro inhibition of C. difficile (defined as a reduction in concentration after inoculation of vegetative C. difficile into fresh stool suspensions) was compared among antibiotic treatment groups. Of 250 patients, 32 (13 %) were asymptomatic carriers of C. difficile. In comparison to patients receiving non-inhibitory antibiotics or prior antibiotics within 90 days, patients currently receiving piperacillin/tazobactam were less likely to be asymptomatic carriers (1/36, 3 versus 7/36, 19 and 15/69, 22 %, respectively; P = 0.024) and more likely to have fecal suspensions with in vitro inhibitory activity against C. difficile (20/28, 71 versus 3/11, 27 and 4/26, 15 %; P = 0.03). Patients receiving other inhibitory antibiotics were not less likely to be asymptomatic carriers than those receiving non-inhibitory antibiotics. Our findings suggest that piperacillin/tazobactam achieves sufficient concentrations in the intestinal tract to inhibit C. difficile colonization during therapy.
Brite, Jennifer; Aslam, Anoshe; Kennington, Jessica; Babady, N. Esther; Calfee, David; Furuya, Yoko; Chen, Donald; Augenbraun, Michael; Ostrowsky, Belinda; Patel, Gopi; Mircescu, Monica; Kak, Vivek; Tuma, Roman; Karre, Teresa A.; Fry, Deborah A.; Duhaney, Yola P.; Moyer, Amber; Mitchell, Denise; Cantu, Sherry; Hsieh, Candace; Warren, Nancy; Martin, Stacy; Willson, Jill; Dickman, Jeanne; Knight, Julie; Delahanty, Kim; Flood, Annemarie; Harrington, Jennifer; Korenstein, Deborah; Eagan, Janet; Sepkowitz, Kent
In 2015, Clostridium difficile testing rates among 30 US community, multispecialty, and cancer hospitals were 14.0, 16.3, and 33.9/1,000 patient-days, respectively. Pooled hospital onset rates were 0.56, 0.84, and 1.57/1,000 patient-days, respectively. Higher testing rates may artificially inflate reported rates of C. difficile infection. C. difficile surveillance should consider testing frequency. PMID:29460760
Norman, Keri N.; Scott, H. Morgan; Harvey, Roger B.; Norby, Bo; Hume, Michael E.; Andrews, Kathleen
Recently, an apparent rise in the number of cases attributed to community-acquired Clostridium difficile infection has led researchers to explore additional sources of infection. The finding of C. difficile in food animals and retail meat has raised concern about potential food-borne and occupational exposures. The objective of this study was to compare C. difficile isolated from a closed population of healthy individuals consisting of both humans and swine in order to investigate possible fo...
Mayer, Melinda J.; Narbad, Arjan; Gasson, Michael J.
Clostridium difficile infection is increasing in both frequency and severity, with the emergence of new highly virulent strains highlighting the need for more rapid and effective methods of control. Here, we show that bacteriophage endolysin can be used to inhibit and kill C. difficile. The genome sequence of a novel bacteriophage that is active against C. difficile was determined, and the bacteriophage endolysin gene was subcloned and expressed in Escherichia coli. The partially purified end...
Nathan E Stone
Full Text Available Nosocomial acquisition of Clostridium difficile is well documented, yet recent studies have highlighted the importance of community acquired infections and identified community associated reservoirs for this pathogen. Multiple studies have implicated companion pets and farm animals as possible sources of community acquired C. difficile infections in humans. To explore the potential role of pet dogs in human C. difficile infections we systematically collected canine fecal samples (n = 197 in Flagstaff, AZ. Additionally, nineteen fecal samples were collected at a local veterinary clinic from diarrheic dogs. We used these combined samples to investigate important questions regarding C. difficile colonization in pet canines: 1 What is the prevalence and diversity of C. difficile in this companion pet population, and 2 Do C. difficile isolates collected from canines genetically overlap with isolates that cause disease in humans? We used a two-step sequence typing approach, including multilocus sequence typing to determine the overall genetic diversity of C. difficile present in Flagstaff canines, and whole-genome sequencing to assess the fine-scale diversity patterns within identical multilocus sequence types from isolates obtained within and among multiple canine hosts. We detected C. difficile in 17% of the canine fecal samples with 10% containing toxigenic strains that are known to cause human disease. Sequencing analyses revealed similar genotypes in dogs and humans. These findings suggest that companion pets are a potential source of community acquired C. difficile infections in humans.
Saeed S. Banawas
Full Text Available Clostridium difficile (C. difficile is the most prevalent causative pathogen of healthcare-associated diarrhea. Notably, over the past 10 years, the number of Clostridium difficile outbreaks has increased with the rate of morbidity and mortality. The occurrence and spread of C. difficile strains that are resistant to multiple antimicrobial drugs complicate prevention as well as potential treatment options. Most C. difficile isolates are still susceptible to metronidazole and vancomycin. Incidences of C. difficile resistance to other antimicrobial drugs have also been reported. Most of the antibiotics correlated with C. difficile infection (CDI, such as ampicillin, amoxicillin, cephalosporins, clindamycin, and fluoroquinolones, continue to be associated with the highest risk for CDI. Still, the detailed mechanism of resistance to metronidazole or vancomycin is not clear. Alternation in the target sites of the antibiotics is the main mechanism of erythromycin, fluoroquinolone, and rifamycin resistance in C. difficile. In this review, different antimicrobial agents are discussed and C. difficile resistance patterns and their mechanism of survival are summarized.
Full Text Available PURPOSE: To look for the presence of intestinal brush border membrane (BBM enzymes in the faecal samples of patients with Clostridium difficile association. METHODS: One hundred faecal samples were investigated for C.difficile toxin (CDT. Simultaneous assays for faecal excretion of intestinal BBM enzymes viz., disaccharidases, alkaline phosphatase (AP and leucine aminopeptidase (LAP were also done. RESULTS: C.difficile toxin was detected in 25 (25% of the samples with a titre ranging from 10 to 160. No significant difference (p>0.05 was seen between the CDT positive and negative groups with any of the disaccharidases studied. However, significant increase (pC.difficile diarrhoea.
Daniela Zilio Larentis
Full Text Available Background. The epidemiology of Clostridium difficile infection has changed over time. Therefore, it is essential to monitor the characteristics of patients at risk of infection and factors associated with poor prognosis. Objective. To evaluate factors associated with C. difficile infection and with poor prognosis in those with documented C. difficile colitis. Methods. A retrospective case-control study of 75 patients with documented C. difficile colitis and 75 controls with hospital-acquired diarrhea of other causes. Stepwise multiple logistic regression was used to identify factors associated with C. difficile infection among patients with hospital-acquired diarrhea. Results. Previous antibiotic treatment (odds ratio (OR, 13.3; 95% confidence interval (CI, 1.40–126.90, abdominal distension (OR, 3.85; 95% CI, 1.35–10.98, and fecal leukocytes (OR, 8.79; 95% CI, 1.41–54.61 are considered as predictors of C. difficile colitis; anorexia was negatively associated with C. difficile infection (OR, 0.15; 95% CI, 0.03–0.66. Enteral tube feeding was independently associated with a composite outcome that included in-hospital mortality, intensive care unit admission, and treatment failure (OR, 3.75; 95%CI, 1.24–11.29. Conclusions. Previous antibiotic use and presence of fecal leukocytes in patients with hospital-acquired diarrhea are associated with C. difficile colitis and enteral tube support with complications associated with C. difficile colitis.
Imane El Meouche
Full Text Available Clostridium difficile intestinal disease is mediated largely by the actions of toxins A (TcdA and B (TcdB, whose production occurs after the initial steps of colonization involving different surface or flagellar proteins. In B. subtilis, the sigma factor SigD controls flagellar synthesis, motility, and vegetative autolysins. A homolog of SigD encoding gene is present in the C.difficile 630 genome. We constructed a sigD mutant in C. difficile 630 ∆erm to analyze the regulon of SigD using a global transcriptomic approach. A total of 103 genes were differentially expressed between the wild-type and the sigD mutant, including genes involved in motility, metabolism and regulation. In addition, the sigD mutant displayed decreased expression of genes involved in flagellar biosynthesis, and also of genes encoding TcdA and TcdB as well as TcdR, the positive regulator of the toxins. Genomic analysis and RACE-PCR experiments allowed us to characterize promoter sequences of direct target genes of SigD including tcdR and to identify the SigD consensus. We then established that SigD positively regulates toxin expression via direct control of tcdR transcription. Interestingly, the overexpression of FlgM, a putative anti-SigD factor, inhibited the positive regulation of motility and toxin synthesis by SigD. Thus, SigD appears to be the first positive regulator of the toxin synthesis in C. difficile.
Gualtero, Sandra Milena; Abril, Lina Alejandra; Camelo, Nathalia; Sanchez, Susi Daniela; Davila, Fabián Antonio; Arias, Gerson; Silva, Edwin; Bustos, Ingrid Gissel; Josa, Diego Fernando; Torres, Isabel Cristina; Zambrano, Luis Carlos; Pareja, María José
Clostridium difficile is the main pathogen related to healthcare-associated diarrhea and it is the cause of 20 to 30% of diarrhea cases caused by antibiotics. In Colombia and Latin America, the knowledge about the epidemiological behavior of this infection is limited. To describe the characteristics of a series of patients with C. difficile infection. We performed a descriptive case series study of patients with C. difficile infection hospitalized in the Fundación Clínica Shaio from January, 2012, to November, 2015. We analyzed 36 patients. The average age was 65 years. The risk factors associated with the infection were: previous use of antibiotics (94.4%), prior hospitalization in the last three months (66.7%) and use of proton pump inhibitors (50%). The most common comorbidities were chronic kidney disease (41.7%) and diabetes mellitus (30.6%). The most frequent symptoms were more than three loose stools per day (97.1%) and abdominal pain (42.9%). According to the severity of the disease, 44.4% of cases were classified as mild to moderate, 38.9% as severe, and 11.1% as complicated or severe. The detection of the toxin by PCR (GeneXpert) was the most common diagnostic procedure (63.8%). Global mortality during hospitalization was 8%. We identified four strains with serotype NAP1/027 and nine samples positive for binary toxin. Clostridium difficile infection should be suspected in patients with diarrhea and traditional risk factors associated with this disease. We report the circulation of the hypervirulent strain serotype NAP1/027 in Colombia, which should be countered with epidemiological surveillance and a prompt diagnosis.
Conclusions: C. difficile NAP1/BI/027 strain and non-027 strains are established pathogens in our hospital. Accordingly, surveillance of C. difficile infections is now part of our nosocomial prevention program.
Bouillaut, Laurent; Self, William T.
Clostridium difficile, a proteolytic Gram-positive anaerobe, has emerged as a significant nosocomial pathogen. Stickland fermentation reactions are thought to be important for growth of C. difficile and appear to influence toxin production. In Stickland reactions, pairs of amino acids donate and accept electrons, generating ATP and reducing power in the process. Reduction of the electron acceptors proline and glycine requires the d-proline reductase (PR) and the glycine reductase (GR) enzyme complexes, respectively. Addition of proline in the medium increases the level of PR protein but decreases the level of GR. We report the identification of PrdR, a protein that activates transcription of the PR-encoding genes in the presence of proline and negatively regulates the GR-encoding genes. The results suggest that PrdR is a central metabolism regulator that controls preferential utilization of proline and glycine to produce energy via the Stickland reactions. PMID:23222730
Peltier, Johann; Shaw, Helen A; Wren, Brendan W; Fairweather, Neil F
Clostridium difficile is a gastrointestinal pathogen but how the bacterium colonises this niche is still little understood. Sortase enzymes covalently attach specific bacterial proteins to the peptidoglycan cell wall and are often involved in colonisation by pathogens. Here we show C. difficile proteins CD2537 and CD3392 are functional substrates of sortase SrtB. Through manipulation of the C-terminal regions of these proteins we show the SPKTG motif is essential for covalent attachment to the cell wall. Two additional putative substrates, CD0183 which contains an SPSTG motif, and CD2768 which contains an SPQTG motif, are not cleaved or anchored to the cell wall by sortase. Finally, using an in vivo asymmetric cleavage assay, we show that despite containing a conserved SPKTG motif, in the absence of SrtB these proteins are localised to disparate cellular compartments.
Jonathan H.K. Chen
Full Text Available The clinical workflow of using chromogenic agar and matrix-assisted laser desorption ionization time-of-fight mass spectrometry (MALDI-TOF MS for Clostridium difficile identification was evaluated. The addition of MALDI-TOF MS identification after the chromID C. difficile chromogenic agar culture could significantly improve the diagnostic accuracy of C. difficile.
Vuletić Biljana; Ristanović Elizabeta; Marković Slavica; Rašković Zorica; Radlović Vladimir; Igrutinović Zoran
Clostridium difficile (CD) is the most common cause of nosocomial diarrhea in adults with high rates of morbidity and mortality. The epidemiology of CD infection (CDI) has changed in the last few decades associated with increasing severity of the infection rate related to the occurrence of NAP1 hypervirulent strain and the emergence of the disease among ambulatory patients and the wider community. Although little is known about CDI in pediatric patients, CD is surprisingly recognized as an im...
Makroczyová, Jana; Jamroškovič, Ján; Krascsenitsová, Eva; Labajová, Nad'a; Barák, Imrich
In rod-shaped bacteria, the proper placement of the division septum at the midcell relies, at least partially, on the proteins of the Min system as an inhibitor of cell division. The main principle of Min system function involves the formation of an inhibitor gradient along the cell axis; however, the establishment of this gradient differs between two well-studied gram-negative and gram-positive bacteria. While in gram-negative Escherichia coli, the Min system undergoes pole-to-pole oscillation, in gram-positive Bacillus subtilis, proper spatial inhibition is achieved by the preferential attraction of the Min proteins to the cell poles. Nevertheless, when E.coli Min proteins are inserted into B.subtilis cells, they still oscillate, which negatively affects asymmetric septation during sporulation in this organism. Interestingly, homologs of both Min systems were found to be present in various combinations in the genomes of anaerobic and endospore-forming Clostridia, including the pathogenic Clostridium difficile. Here, we have investigated the localization and behavior of C.difficile Min protein homologs and showed that MinDE proteins of C.difficile can oscillate when expressed together in B.subtilis cells. We have also investigated the effects of this oscillation on B.subtilis sporulation, and observed decreased sporulation efficiency in strains harboring the MinDE genes. Additionally, we have evaluated the effects of C.difficile Min protein expression on vegetative division in this heterologous host. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.
Michael A Rubin
Full Text Available BACKGROUND: Clostridium difficile is one of the most common and important nosocomial pathogens, causing severe gastrointestinal disease in hospitalized patients. Although "bundled" interventions have been proposed and promoted, optimal control strategies remain unknown. METHODS: We designed an agent-based computer simulation of nosocomial C. difficile transmission and infection, which included components such as: patients and health care workers, and their interactions; room contamination via C. difficile shedding; C. difficile hand carriage and removal via hand hygiene; patient acquisition of C. difficile via contact with contaminated rooms or health care workers; and patient antimicrobial use. We then introduced six interventions, alone and "bundled" together: aggressive C. difficile testing; empiric isolation and treatment of symptomatic patients; improved adherence to hand hygiene and contact precautions; improved use of soap and water for hand hygiene; and improved environmental cleaning. All interventions were tested using values representing base-case, typical intervention, and optimal intervention scenarios. FINDINGS: In the base-case scenario, C. difficile infection rates ranged from 8-21 cases/10,000 patient-days, with a case detection fraction between 32%-50%. Implementing the "bundle" at typical intervention levels had a large impact on C. difficile acquisition and infection rates, although intensifying the intervention to optimal levels had much less additional impact. Most of the impact came from improved hand hygiene and empiric isolation and treatment of suspected C. difficile cases. CONCLUSION: A "bundled" intervention is likely to reduce nosocomial C. difficile infection rates, even under typical implementation conditions. Real-world implementation of the "bundle" should focus on those components of the intervention that are likely to produce the greatest impact on C. difficile infection rates, such as hand hygiene and empiric
Full Text Available Clostridium difficile spores play a pivotal role in the transmission of infectious diarrhoea, but in order to cause disease spores must complete germination and return to vegetative cell growth. While the mechanisms of spore germination are well understood in Bacillus, knowledge of C. difficile germination remains limited. Previous studies have shown that bile salts and amino acids play an important role in regulating the germination response of C. difficile spores. Taurocholate, in combination with glycine, can stimulate germination, whereas chenodeoxycholate has been shown to inhibit spore germination in a C. difficile clinical isolate. Our recent studies of C. difficile sporulation characteristics have since pointed to substantial diversity among different clinical isolates. Consequently, in this study we investigated how the germination characteristics of different C. difficile isolates vary in response to bile salts. By analysing 29 isolates, including 16 belonging to the BI/NAP1/027 type, we show that considerable diversity exists in both the rate and extent of C. difficile germination in response to rich medium containing both taurocholate and glycine. Strikingly, we also show that although a potent inhibitor of germination for some isolates, chenodeoxycholate does not inhibit the germination, or outgrowth, of all C. difficile strains. Finally, we provide evidence that components of rich media may induce the germination of C. difficile spores, even in the absence of taurocholate. Taken together, these data suggest that the mechanisms of C. difficile spore germination in response to bile salts are complex and require further study. Furthermore, we stress the importance of studying multiple isolates in the future when analysing the nutrients or chemicals that either stimulate or inhibit C. difficile spore germination.
Buonomo, Erica L; Petri, William A
Clostridium difficile is a gram-positive, spore forming anaerobe that infects the gut when the normal microbiota has been disrupted. C. difficile infection (CDI) is the most common cause of hospital acquired infection in the United States, and the leading cause of death due to gastroenteritis. Patients suffering from CDI have varying symptoms which range from mild diarrhea to pseudomembranous colitis and death. The involvement of the immune response to influence disease severity is just beginning to be investigated. There is evidence that the immune response can facilitate either protective or pathogenic phenotypes, suggesting it plays a multifaceted role during CDI. In addition to the immune response, the microbiota is pivotal in dictating the pathogenesis to CDI. A healthy microbiota effectively inhibits infection by restricting the ability of C. difficile to expand in the colon. Thus, understanding which immune mediators and components of the microbiota play beneficial roles during CDI will be important to future therapeutic developments. This review outlines how the microbiota can modulate specific immune mediators, such as IL-23 and others, to influence disease outcome. Copyright © 2016 Elsevier Ltd. All rights reserved.
Full Text Available Clostridium difficile is a Gram-positive bacillus that has become one of the main hospital-acquired human gastrointestinal infections in recent years. Its incidence is on the rise, involving more virulent strains, affecting new and previously uncontemplated groups of patients, and producing changes in clinical presentation and treatment response that influence disease outcome. Early diagnosis and disease stratification based on the severity of C. difficile infection are essential for therapeutic management and the implementation of containment measures. However, the speed at which new strains with greater pathogenicity are developing is surpassing that of the development of new drugs, making it necessary to validate other therapeutic options. The present article is a review of the epidemiologic, pathophysiologic, diagnostic, and therapeutic aspects of C. difficile infection, from its first isolation to the present date, that aims to contribute to the preparation of general physicians and specialists, so that patients with this infection receive opportune and quality medical attention.
Gweon, Tae-Geun; Choi, Myung-Gyu; Baeg, Myong Ki; Lim, Chul-Hyun; Park, Jae Myung; Lee, In Seok; Kim, Sang Woo; Lee, Dong-Gun; Park, Yeon Joon; Lee, Jong Wook
To investigate the incidence and clinical outcome of Clostridium difficile (C. difficile) associated diarrhea (CDAD) in patients with hematologic disease. We retrospectively reviewed the medical records of patients who underwent C. difficile testing in a tertiary hospital in 2011. The incidence and risk factors for CDAD and its clinical course including recurrence and mortality were assessed in patients with hematologic disease and compared with those in patients with nonhematologic disease. About 320 patients were diagnosed with CDAD (144 patients with hematologic disease; 176 with nonhematologic disease). The incidence of CDAD in patients with hematologic disease was estimated to be 36.7 cases/10000 patient hospital days, which was higher than the 5.4 cases/10000 patient hospital days in patients with nonhematologic disease. Recurrence of CDAD was more frequent in patients with hematologic disease compared to those with nonhematologic disease (18.8% vs 8.5%, P associated with higher re-use of causative antibiotics for CDAD. Mortality due to CDAD did not differ between the two groups. Multivariate analysis showed that intravenous immunoglobulin was the only significant factor associated with a lower rate of recurrence of CDAD in patients with hematologic disease. The incidence and recurrence of CDAD was higher in patients with hematologic disease than in those with nonhematologic disease.
Full Text Available Healthcare decision-makers are increasingly expected to balance increasing demand for health services with a finite budget. The role of economic evaluation in healthcare is increasing and this research provides decision-makers with new information about the management of Clostridium difficile infection, from an economic perspective.A model-based economic evaluation was undertaken to identify the most cost-effective healthcare intervention relating to the reduction of Clostridium difficile transmission. Efficacy evidence was synthesised from the literature and was used to inform the effectiveness of both bundled approaches and stand-alone interventions, where appropriate intervention combinations were coupled together. Changes in health outcomes were estimated by combining information about intervention effectiveness and its subsequent impact on quality of life.A bundled approach of improving hand hygiene and environmental cleaning produces the best combination of increased health benefits and cost-savings. It has the highest mean net monetary benefit when compared to all other interventions. This intervention remains the optimal decision under different clinical circumstances, such as when mortality rate and patient length of stay are increased. Bundled interventions offered the best opportunity for health improvements.These findings provide healthcare decision-makers with novel information about the allocation of scarce resources relating to Clostridium difficile. If investments are not made in interventions that clearly yield gains in health outcomes, the allocation and use of scarce healthcare resources is inappropriate and improvements in health outcomes will be forgone.
Rodrigo Otávio Silveira Silva
Full Text Available Despite of the substantial role of Clostridium difficile in causing diarrhea and colitis in foals, there have been no confirmed diagnoses of disease caused by this bacteria in Brazil. In this paper, we describe confirmed cases of colitis caused by C. difficile in two foals in Brazil. Two five-month-old foals with a five-day history of diarrhea after antibiotic treatment for a respiratory disease were treated at the Veterinary Hospital of the Universidade Federal de Minas Gerais. C. difficile A/B toxins were detected, and toxigenic strains of C. difficile were isolated from the foals' feces. The treatment was based on fluid therapy and antibiotics (metronidazole and ceftiofur, and the animals experienced a gradual recovery. The association between the medical history, clinical signs, laboratory exam results and therapeutic success confirmed the diagnosis of C. difficile-associated diarrhea. The present report raises the possibility that C. difficile is also a pathogen in equines in Brazil and highlights the need for up to date routine laboratory protocols for the diagnosis of this disease.Apesar da importância de Clostridium difficile como agente causador de diarreia e colite em potros, inexistem relatos confirmados de tal doença no Brasil. O objetivo deste trabalho foi descrever dois casos confirmados de diarreia causados por C. difficile em potros, ocorridos em Minas Gerais, Brasil. Os animais, com cinco meses de idade, foram encaminhados ao Hospital Veterinário da Universidade Federal de Minas Gerais (UFMG com histórico de cinco dias de diarreia após antibioticoterapia com penicilina para uma possível pneumonia. Ambos os animais foram positivos para detecção das toxinas A/B de C. difficile e isolados toxigênicas de C. difficile foram isoladas de amostras de fezes. Os animais apresentaram melhora gradual com o tratamento baseado em metronidazol e fluidoterapia e receberam alta após sete dias. A associação do quadro clínico, exames
Knecht, H.; Neulinger, S.C.; Heinsen, F.A.; Knecht, C.; Schilhabel, A.; Schmitz, R.A.; Zimmermann, A.; Martins dos Santos, V.A.P.; Ferrer, R.; Rosenstiel, P.C.; Schreiber, S.; Friedrichs, A.K.; Ott, S.J.
Clostridium difficile infections are an emerging health problem in the modern hospital environment. Severe alterations of the gut microbiome with loss of resistance to colonization against C. difficile are thought to be the major trigger, but there is no clear concept of how C. difficile infection
Lin, Hsiao-Ju; Hung, Yuan-Pin; Liu, Hsiu-Chuan; Lee, Jen-Chieh; Lee, Chih-I; Wu, Yi-Hui; Tsai, Pei-Jane; Ko, Wen-Chien
Patients with toxigenic Clostridium difficile colonization (tCDC) are at risk of developing C. difficile-associated diarrhea (CDAD). However, the risk factors of hospitalized patients with tCDC developing CDAD are not clear. We conducted an 18-month prospective study at a medical ward in a district hospital in southern Taiwan. Within 48 hours of admission, weekly stool samples from asymptomatic hospitalized patients were obtained to detect fecal CDC. A polymerase chain reaction for tcdB was performed to determine toxigenic isolates. CDAD was diagnosed if the patient had diarrhea and toxigenic C. difficile present in a stool sample. A total 483 patients with stool samples were eligible for the study. Eighty-six (17.8%) patients had tCDC after screening, of whom 14 (16.3%) developed CDAD during follow-up. Among those with tCDC, patients with subsequent CDAD were more likely to have diabetes mellitus (p = 0.01) and to have received piperacillin-tazobactam (p = 0.04), or proton-pump inhibitors (PPIs; p = 0.04) than those without developing CDAD. The variables were statistically significant as determined by multivariate analysis. However, the 60-day crude mortality rates among tCDC patients with and without subsequent development of CDAD were similar. Diabetes mellitus and recent receipt of piperacillin-tazobactam or PPIs are independent risk factors for the development of CDAD among hospitalized patients with tCDC. Copyright © 2013. Published by Elsevier B.V.
Thompson, Angela D.; Limbago, Brandi; McDonald, L. Clifford; Bonkosky, Michelle; Heimer, Robert; Meek, James; Mai, Volker; Braden, Christopher
Clostridium difficile, the most commonly recognized diarrheagenic pathogen among hospitalized persons, can cause outpatient diarrhea. Of 1,091 outpatients with diarrhea, we found 43 (3.9%) who were positive for C. difficile toxin. Only 7 had no recognized risk factors, and 3 had neither risk factors nor co-infection with another enteric pathogen. PMID:22000379
L. N. Mazankova
Full Text Available The review of literature presents data on the incidence and characteristics of the current development of antibiotic-associated diarrhea (AAD in children. Presented research materials of Russian and foreign scientists on risk factors activation toxigenic strains Cl. difficile, showed the relationship between the depth microecologi-cal metabolomical violations and Cl. difficile-infection in children.
Full Text Available Reactive arthritis is a rare complication of Clostridium difficile enterocolitis, especially in children. We review the 6 pediatric cases published in the English and non-English literature and discuss their clinical presentation, outcome, treatment, and pathophysiology. We also report the seventh case of Clostridium difficile reactive arthritis in a 6-year-old boy who was treated with amoxicillin-clavulanate for 10 days because of an upper respiratory infection. After the antibiotic course, the child developed at the same time diarrhea with positive stool culture for Clostridium difficile and an asymmetric polyarthritis. Nonsteroidal anti-inflammatory drugs and metronidazole completely resolved the pain, joint swelling, and diarrhea. After twelve months of follow-up there has been no recurrence. This report confirms the self-limiting course of Clostridium difficile reactive arthritis. Clostridium difficile testing in children with gastrointestinal symptoms and acute onset of joint pain should be always considered.
Fenger, R V; Linneberg, A; Tvede, M
The incidence of Clostridium difficile-associated infections is increasing, but it remains to be defined whether any change in the seroprevalence of C. difficile has also occurred. In a population-based study of the general adult population, 734 subjects, aged 15-69 years, were examined on two...... was about four times higher in 1998 than in 1990. In conclusion, the observed increase in seroprevalence suggests a higher exposure to C. difficile in the general Danish adult population....... occasions 8 years apart (1990 and 1998) for the presence of antibodies against C. difficile in serum. The overall seroprevalence of C. difficile increased significantly from 19% in 1990 to 27% in 1998 (Pincreased with increasing age in both 1990 and 1998, but the increase...
Rodrigo Otávio Silveira Silva
Full Text Available In spite of the substantial role of Clostridium difficile in causing diarrhea in piglets, there have been few reports of the disease caused by this bacterium in Rio Grande do Sul, Brazil. In this paper, we describe an outbreak of C. difficile-associated diarrhea in a pig farm in Brazil. The diarrhea rate increased in piglets 1-to-7 days old from an average of 2% to approximately 20%. Necropsied piglets showed mesocolon edema, and in a histological evaluation, severe necrotizing neutrophilic colitis was observed. The intestinal contents were positive for the A/B toxins of C. difficile and negative for other tested enteropathogens. The association between the clinical signs, post mortem findings and laboratory exams confirmed the diagnosis of C. difficile-associated diarrhea. The present report confirms C. difficile as a pathogen in swine in Brazil and highlights the need for up to date routine laboratory protocols for the diagnosis of this disease in swine.
Full Text Available Abstract Background Major Clostridium difficile virulence factors are the exotoxins TcdA and TcdB. Due to the large size and poor stability of the proteins, the active recombinant TcdA and TcdB have been difficult to produce. Results The toxin genes tcdA and tcdB were amplified by PCR using chromosomal DNA from a toxigenic strain as a template, and cloned into a shuttle vector pHis1522. The sequences of both tcdA and tcdB genes in the vector have been verified by DNA sequencing. The constructs were transformed into B. megaterium protoplasts and the protein expression was controlled under a xylose promoter. The recombinant toxins (rTcdA and rTcdB were purified from bacterial crude extracts. Approximately 5 – 10 mg of highly purified recombinant toxins were obtained from one liter of bacterial culture. The resulting rTcdA and rTcdB had similar molecular masses to the native toxins, and their biological activities were found to be similar to their native counterparts after an extensive examination. Conclusion We have generated the full length and active recombinant TcdA and TcdB in Bacillus megaterium.
Buchan, Blake W; Mackey, Tami-Lea A; Daly, Judy A; Alger, Garrison; Denys, Gerald A; Peterson, Lance R; Kehl, Sue C; Ledeboer, Nathan A
We compared the Portrait Toxigenic C. difficile Assay, a new semiautomated sample-to-result molecular test, to a toxigenic bacterial culture/cell cytotoxin neutralization assay (TBC/CCNA) for the detection of toxigenic Clostridium difficile in 549 stool specimens. Stool specimens were also tested by one of three alternative FDA-cleared molecular tests for toxigenic C. difficile (Xpert C. difficile, Illumigene C. difficile, or GeneOhm Cdiff). The sensitivities and specificities of the molecular tests compared to TBC/CCNA were as follows: 98.2% and 92.8% for the Portrait assay, 100% and 91.7% for the Xpert assay, 93.3% and 95.1% for the Illumigene assay, and 97.4% and 98.5% for the GeneOhm assay, respectively. The majority of Portrait false-positive results (20/31; 64.5%) were also positive for C. difficile by an alternative molecular test, suggesting an increased sensitivity compared to the culture-based "gold standard" method. The Portrait test detected an assay input of 30 CFU in 100% of spiked samples and detected an input of 10 CFU in 96.7% of samples tested.
Full Text Available BACKGROUND: We investigated whether chemotherapy with the presence or absence of antibiotics against different kinds of cancer changed the gastrointestinal microbiota. METHODOLOGY/PRINCIPAL FINDINGS: Feces of 17 ambulant patients receiving chemotherapy with or without concomitant antibiotics were analyzed before and after the chemotherapy cycle at four time points in comparison to 17 gender-, age- and lifestyle-matched healthy controls. We targeted 16S rRNA genes of all bacteria, Bacteroides, bifidobacteria, Clostridium cluster IV and XIVa as well as C. difficile with TaqMan qPCR, denaturing gradient gel electrophoresis (DGGE fingerprinting and high-throughput sequencing. After a significant drop in the abundance of microbiota (p = 0.037 following a single treatment the microbiota recovered within a few days. The chemotherapeutical treatment marginally affected the Bacteroides while the Clostridium cluster IV and XIVa were significantly more sensitive to chemotherapy and antibiotic treatment. DGGE fingerprinting showed decreased diversity of Clostridium cluster IV and XIVa in response to chemotherapy with cluster IV diversity being particularly affected by antibiotics. The occurrence of C. difficile in three out of seventeen subjects was accompanied by a decrease in the genera Bifidobacterium, Lactobacillus, Veillonella and Faecalibacterium prausnitzii. Enterococcus faecium increased following chemotherapy. CONCLUSIONS/SIGNIFICANCE: Despite high individual variations, these results suggest that the observed changes in the human gut microbiota may favor colonization with C. difficile and Enterococcus faecium. Perturbed microbiota may be a target for specific mitigation with safe pre- and probiotics.
F. M. Trejo
Full Text Available Para comparar diferentes métodos de diagnóstico de diarreas asociadas a Clostridium difficile desarrollados en el marco de un estudio colaborativo, se analizaron filtrados de materia fecal de pacientes con sintomatología compatible con esta patología. Se evaluó la actividad biológica sobre células Vero (ensayo biológico, la reactividad frente a anticuerpos anti-TcdA y anti-TcdB (dot blot y la presencia de secuencias del gen tcdB por PCR. De 177 muestras analizadas por el ensayo biológico, 44 tuvieron títulos mayores o iguales que 64. Diecinueve muestras fueron a la vez positivas en el ensayo biológico y en el análisis por PCR. Se analizaron 149 muestras por dot blot utilizando anticuerpos anti-TcdA y anti-TcdB; 46 muestras resultaron positivas para ambas toxinas, 12 muestras fueron positivas sólo para TcdB y 5 muestras sólo para TcdA. Las divergencias entre los diferentes métodos podrían estar relacionadas con la presencia de genes truncados, con un bajo número de microorganismos en las muestras analizadas o con la degradación de las toxinas. Los resultados presentados demuestran la necesidad de implementar alternativas diagnósticas que se adapten a la compleja realidad epidemiológica de este importante patógeno intestinal.In order to compare different methods for the diagnosis of Clostridium difficile-associated diarrhea, fecal filtrates from patients presenting symptoms compatible with this condition, were analyzed. Biological activity on Vero cells (biological assay, dot blot with antibodies anti-TcdA and anti-TcdB, and a PCR assay for the tcdB gene, were evaluated. Titles of biological assays were ≥ 64 for 44 out of 177 samples. Nineteen samples were positive in both biological and PCR assays. The analysis by dot blot using anti-TcdA and anti-TcdB antibodies showed that 46 samples out of 149 were positive for both toxins whereas 12 samples were only positive for TcdB, and 5 samples only positive for TcdA. Discrepancies
Full Text Available Using Streptococcus pyogenes as a model, we previously established a stepwise computational workflow to effectively identify species-specific DNA signatures that could be used as PCR primer sets to detect target bacteria with high specificity and sensitivity. In this study, we extended the workflow for the rapid development of PCR assays targeting Enterococcus faecalis, Enterococcus faecium, Clostridium perfringens, Clostridium difficile, Clostridium tetani , and Staphylococcus aureus , which are of safety concern for human tissue intended for transplantation. Twenty-one primer sets that had sensitivity of detecting 5–50 fg DNA from target bacteria with high specificity were selected. These selected primer sets can be used in a PCR array for detecting target bacteria with high sensitivity and specificity. The workflow could be widely applicable for the rapid development of PCR-based assays for a wide range of target bacteria, including those of biothreat agents.
Alison C Pitts
Full Text Available Bacterial microcompartments form a protective proteinaceous barrier around metabolic enzymes that process unstable or toxic chemical intermediates. The genome of the virulent, multidrug-resistant Clostridium difficile 630 strain contains an operon, eut, encoding a bacterial microcompartment with genes for the breakdown of ethanolamine and its utilisation as a source of reduced nitrogen and carbon. The C. difficile eut operon displays regulatory genetic elements and protein encoding regions in common with homologous loci found in the genomes of other bacteria, including the enteric pathogens Salmonella enterica and Enterococcus faecalis. The crystal structures of two microcompartment shell proteins, CD1908 and CD1918, and an uncharacterised protein with potential enzymatic activity, CD1925, were determined by X-ray crystallography. CD1908 and CD1918 display the same protein fold, though the order of secondary structure elements is permuted in CD1908 and this protein displays an N-terminal β-strand extension. These proteins form hexamers with molecules related by crystallographic and non-crystallographic symmetry. The structure of CD1925 has a cupin β-barrel fold and a putative active site that is distinct from the metal-ion dependent catalytic cupins. Thin-section transmission electron microscopy of Escherichia coli over-expressing eut proteins indicates that CD1918 is capable of self-association into arrays, suggesting an organisational role for CD1918 in the formation of this microcompartment. The work presented provides the basis for further study of the architecture and function of the C. difficile eut microcompartment, its role in metabolism and the wider consequences of intestinal colonisation and virulence in this pathogen.
Fettucciari, Katia; Ponsini, Pamela; Gioè, Davide; Macchioni, Lara; Palumbo, Camilla; Antonelli, Elisabetta; Coaccioli, Stefano; Villanacci, Vincenzo; Corazzi, Lanfranco; Marconi, Pierfrancesco; Bassotti, Gabrio
Clostridium difficile causes nosocomial/antibiotic-associated diarrhoea and pseudomembranous colitis. The major virulence factors are toxin A and toxin B (TcdB), which inactivate GTPases by monoglucosylation, leading to cytopathic (cytoskeleton alteration, cell rounding) and cytotoxic effects (cell-cycle arrest, apoptosis). C. difficile toxins breaching the intestinal epithelial barrier can act on underlying cells, enterocytes, colonocytes, and enteric neurons, as described in vitro and in vivo, but until now no data have been available on enteric glial cell (EGC) susceptibility. EGCs are crucial for regulating the enteric nervous system, gut homeostasis, the immune and inflammatory responses, and digestive and extradigestive diseases. Therefore, we evaluated the effects of C. difficile TcdB in EGCs. Rat-transformed EGCs were treated with TcdB at 0.1-10 ng/ml for 1.5-48 h, and several parameters were analysed. TcdB induces the following in EGCs: (1) early cell rounding with Rac1 glucosylation; (2) early G2/M cell-cycle arrest by cyclin B1/Cdc2 complex inactivation caused by p27 upregulation, the downregulation of cyclin B1 and Cdc2 phosphorylated at Thr161 and Tyr15; and (3) apoptosis by a caspase-dependent but mitochondria-independent pathway. Most importantly, the stimulation of EGCs with TNF-α plus IFN-γ before, concomitantly or after TcdB treatment strongly increased TcdB-induced apoptosis. Furthermore, EGCs that survived the cytotoxic effect of TcdB did not recover completely and showed not only persistent Rac1 glucosylation, cell-cycle arrest and low apoptosis but also increased production of glial cell-derived neurotrophic factor, suggesting self-rescuing mechanisms. In conclusion, the high susceptibility of EGCs to TcdB in vitro, the increased sensitivity to inflammatory cytokines related to apoptosis and the persistence of altered functions in surviving cells suggest an important in vivo role of EGCs in the pathogenesis of C. difficile infection.
Johan A. Kers
Full Text Available Lantibiotics offer an untapped pipeline for the development of novel antibiotics to treat serious Gram-positive (+ infections including Clostridium difficile. Mutacin 1140 (MU1140 is a lantibiotic produced by Streptococcus mutans and acts via a novel mechanism of action, which may limit the development of resistance. This study sought to identify a lead compound for the treatment of C. difficile associated diarrhea (CDAD. Compounds were selected from a saturation mutagenesis library of 418 single amino acid variants of MU1140. Compounds were produced by small scale fermentation, purified, characterized and then subjected to a panel of assays aimed at identifying the best performers. The screening assays included: in vitro susceptibility testing [MIC against Micrococcus luteus, Clostridium difficile, vancomycin-resistant enterococci (VRE, Staphylococcus aureus, Streptococcus pneumonia, Mycobacterium phlei, and Pseudomonas aeruginosa; cytotoxicity screening on HepG2 hepatocytes; in vitro pharmacological profiling with the Safety Screen 44TM, metabolic and chemical stability in biologically relevant fluids (FaSSGF, FaSSIF and serum; and efficacy in vivo]. Several lantibiotic compounds had better MIC against C. difficile, compared to vancomycin, but not against other bacterial species tested. The Safety Screen 44TMin vitro pharmacological profiling assay suggested that this class of compounds has relatively low overall toxicity and that compound OG253 (MU1140, Phe1Ile is not likely to present inadvertent off-target effects, as evidenced by a low promiscuity score. The in vitro cytotoxicity assay also indicated that this class of compounds was characterized by low toxicity; the EC50 of OG253 was 636 mg/mL on HepG2 cells. The half-life in simulated gastric fluid was >240 min. for all compound tested. The stability in simulated intestinal fluid ranged between a half-life of 5 min to >240 min, and paralleled the half-life in serum. OG253 ultimately
Kers, Johan A; Sharp, Robert E; Defusco, Anthony W; Park, Jae H; Xu, Jin; Pulse, Mark E; Weiss, William J; Handfield, Martin
Lantibiotics offer an untapped pipeline for the development of novel antibiotics to treat serious Gram-positive (+) infections including Clostridium difficile . Mutacin 1140 (MU1140) is a lantibiotic produced by Streptococcus mutans and acts via a novel mechanism of action, which may limit the development of resistance. This study sought to identify a lead compound for the treatment of C. difficile associated diarrhea (CDAD). Compounds were selected from a saturation mutagenesis library of 418 single amino acid variants of MU1140. Compounds were produced by small scale fermentation, purified, characterized and then subjected to a panel of assays aimed at identifying the best performers. The screening assays included: in vitro susceptibility testing [MIC against Micrococcus luteus , Clostridium difficile , vancomycin-resistant enterococci (VRE), Staphylococcus aureus , Streptococcus pneumonia , Mycobacterium phlei , and Pseudomonas aeruginosa ; cytotoxicity screening on HepG2 hepatocytes; in vitro pharmacological profiling with the Safety Screen 44 TM , metabolic and chemical stability in biologically relevant fluids (FaSSGF, FaSSIF and serum); and efficacy in vivo ]. Several lantibiotic compounds had better MIC against C. difficile , compared to vancomycin, but not against other bacterial species tested. The Safety Screen 44 TM in vitro pharmacological profiling assay suggested that this class of compounds has relatively low overall toxicity and that compound OG253 (MU1140, Phe1Ile) is not likely to present inadvertent off-target effects, as evidenced by a low promiscuity score. The in vitro cytotoxicity assay also indicated that this class of compounds was characterized by low toxicity; the EC 50 of OG253 was 636 mg/mL on HepG2 cells. The half-life in simulated gastric fluid was >240 min. for all compound tested. The stability in simulated intestinal fluid ranged between a half-life of 5 min to >240 min, and paralleled the half-life in serum. OG253 ultimately
Surawicz, Christina M.
Diarrhea is a common side effect of antibiotics. Antibiotics can cause diarrhea in 5-25% of individuals who take them but its occurrence is unpredictable. Diarrhea due to antibiotics is called antibiotic-associated diarrhea (AAD). Diarrhea may be mild and resolve when antibiotics are discontinued, or it may be more severe. The most severe form of AAD is caused by overgrowth of Clostridium difficile which can cause severe diarrhea, colitis, pseudomembranous colitis, or even fatal toxic megacolon. Rates of diarrhea vary with the specific antibiotic as well as with the individual susceptibility.
Boudry, Pierre; Semenova, Ekaterina; Monot, Marc; Datsenko, Kirill A.; Lopatina, Anna; Sekulovic, Ognjen; Ospina-Bedoya, Maicol; Fortier, Louis-Charles; Severinov, Konstantin; Dupuy, Bruno
ABSTRACT Clostridium difficile is the cause of most frequently occurring nosocomial diarrhea worldwide. As an enteropathogen, C. difficile must be exposed to multiple exogenous genetic elements in bacteriophage-rich gut communities. CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR-associated) systems allow bacteria to adapt to foreign genetic invaders. Our recent data revealed active expression and processing of CRISPR RNAs from multiple type I-B CRISPR arrays in C. difficile reference strain 630. Here, we demonstrate active expression of CRISPR arrays in strain R20291, an epidemic C. difficile strain. Through genome sequencing and host range analysis of several new C. difficile phages and plasmid conjugation experiments, we provide evidence of defensive function of the CRISPR-Cas system in both C. difficile strains. We further demonstrate that C. difficile Cas proteins are capable of interference in a heterologous host, Escherichia coli. These data set the stage for mechanistic and physiological analyses of CRISPR-Cas-mediated interactions of important global human pathogen with its genetic parasites. PMID:26330515
White, Duncan R; Hamilton, Keith W; Pegues, David A; Hanish, Asaf; Umscheid, Craig A
OBJECTIVE To evaluate the effectiveness of a computerized clinical decision support intervention aimed at reducing inappropriate Clostridium difficile testing DESIGN Retrospective cohort study SETTING University of Pennsylvania Health System, comprised of 3 large tertiary-care hospitals PATIENTS All adult patients admitted over a 2-year period INTERVENTION Providers were required to use an order set integrated into a commercial electronic health record to order C. difficile toxin testing. The order set identified patients who had received laxatives within the previous 36 hours and displayed a message asking providers to consider stopping laxatives and reassessing in 24 hours prior to ordering C. difficile testing. Providers had the option to continue or discontinue laxatives and to proceed with or forgo testing. The primary endpoint was the change in inappropriate C. difficile testing, as measured by the number of patients who had C. difficile testing ordered while receiving laxatives. RESULTS Compared to the 1-year baseline period, the intervention resulted in a decrease in the proportion of inappropriate C. difficile testing (29.6% vs 27.3%; P=.02). The intervention was associated with an increase in the number of patients who had laxatives discontinued and did not undergo C. difficile testing (5.8% vs 46.4%; Ptesting (5.4% vs 35.2%; Ptesting and improving the timely discontinuation of laxatives. Infect Control Hosp Epidemiol 2017;38:1204-1208.
Loo, Vivian G; Brassard, Paul; Miller, Mark A
OBJECTIVE To determine the risk of Clostridium difficile transmission from index cases with C. difficile infection (CDI) to their household contacts and domestic pets. DESIGN A prospective study from April 2011 to June 2013. SETTING Patients with CDI from Canadian tertiary care centers. PARTICIPANTS Patients with CDI, their household human contacts, and pets. METHODS Epidemiologic information and stool or rectal swabs were collected from participants at enrollment and monthly for up to 4 months. Pulsed-field gel electrophoresis (PFGE) was performed on C. difficile isolates. Probable transmission was defined as the conversion of a C. difficile culture-negative contact to C. difficile culture-positive contact with a PFGE pattern indistinguishable or closely related to the index case. Possible transmission was defined as a contact with a positive C. difficile culture at baseline with a strain indistinguishable or closely related to the index case. RESULTS A total of 51 patients with CDI participated in this study; 67 human contacts and 15 pet contacts were included. Overall, 9 human contacts (13.4%) were C. difficile culture positive; 1 contact (1.5%) developed CDI; and 8 contacts were asymptomatic. Of 67 human contacts, probable transmission occurred in 1 human contact (1.5%) and possible transmission occurred in 5 human contacts (7.5%). Of 15 pet contacts, probable transmission occurred in 3 (20%) and possible transmission occurred in 1 (6.7%). CONCLUSIONS There was a high proportion of C. difficile culture positivity at 13.4% among human contacts and asymptomatic carriage of domestic pets reached 26.7%. These results suggest that household transmission of C. difficile may be a source of community-associated cases. Infect Control Hosp Epidemiol 2016;1-7.
Shrestha, Ritu; Lockless, Steve W; Sorg, Joseph A
Clostridium difficile has become one of the most common bacterial pathogens in hospital-acquired infections in the United States. Although C. difficile is strictly anaerobic, it survives in aerobic environments and transmits between hosts via spores. C. difficile spore germination is triggered in response to certain bile acids and glycine. Although glycine is the most effective co-germinant, other amino acids can substitute with varying efficiencies. Of these, l-alanine is an effective co-germinant and is also a germinant for most bacterial spores. Many endospore-forming bacteria embed alanine racemases into their spore coats, and these enzymes are thought to convert the l-alanine germinant into d-alanine, a spore germination inhibitor. Although the C. difficile Alr2 racemase is the sixth most highly expressed gene during C. difficile spore formation, a previous study reported that Alr2 has little to no role in germination of C. difficile spores in rich medium. Here, we hypothesized that Alr2 could affect C. difficile l-alanine-induced spore germination in a defined medium. We found that alr2 mutant spores more readily germinate in response to l-alanine as a co-germinant. Surprisingly, d-alanine also functioned as a co-germinant. Moreover, we found that Alr2 could interconvert l- and d-serine and that Alr2 bound to l- and d-serine with ∼2-fold weaker affinity to that of l- and d-alanine. Finally, we demonstrate that l- and d-serine are also co-germinants for C. difficile spores. These results suggest that C. difficile spores can respond to a diverse set of amino acid co-germinants and reveal that Alr2 can accommodate serine as a substrate. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
M. Beatriz Souza Dias
Full Text Available The objective of this study was to describe a pseudo-outbreak of C. difficile in a hospital, following a change in the method used to detect the toxin. In February 2002, there were two cases of CDAD and in March 7 occurred, coinciding with a change of the test (from detection of toxin A to toxin A/B. An outbreak was suspected. Active surveillance and education of staff were started. A CDAD case was defined as a patient with acute onset of diarrhea (³ three episodes of liquid stools and a positive stool test. They were classified as hospital or community-acquired. Stool samples were also collected for C. difficile culture and isolates were typed using AP-PCR. From March 2002 through December 2003 there were 138 cases of CDAD: 70% were hospital-acquired and among the 30% with CDAD present on admission, most (81% came directly from the community (50% had no history of hospitalization. Fifty-two percent of hospital-acquired CDAD and 94% of cases on admission had already used antibiotics. The incidence of CDAD in hospitalized patients during surveillance was 3.3 per 1000 patient-admissions. The incidence of CDAD present on admission was 6.1/1000 patients. Sixteen isolates were typed and presented 13 different profiles. In conclusion, the CDAD increase in our study occurred due to change in diagnostic methods and not due to an outbreak, as suspected initially. The incidence in hospitalized patients was much lower than in reported outbreaks. There were 13 molecular types suggesting that an outbreak did not occur. CDAD was largely community-acquired.O objetivo deste estudo foi descrever um pseudo-surto de C. difficile em um hospital após a troca do método de detecção de toxina. Em fevereiro de 2002 houve dois casos de DACD e em março ocorreram sete casos, que coincidiram com a mudança de teste (que detectava apenas toxina A e passou a detectar toxinas A e B. Foi suspeitado que houvesse um surto e vigilância ativa e reforço educacional para os
Seo, Ja Young; Jeong, Ji Hun; Kim, Kyung Hee; Ahn, Jeong-Yeal; Park, Pil-Whan; Seo, Yiel-Hea
Clostridium difficile is a major pathogen responsible for nosocomial infectious diarrhea. We explored optimal laboratory strategies for diagnosis of C. difficile infection (CDI) in our clinical settings, a 1400-bed tertiary care hospital. Using 191 fresh stool samples from adult patients, we evaluated the performance of Xpert C. difficile (Xpert CD), C. diff Quik Chek Complete (which simultaneously detects glutamate dehydrogenase [GDH] and C. difficile toxins [CDT]), toxigenic culture, and a two-step algorithm composed of GDH/CDT as a screening test and Xpert CD as a confirmatory test. Clostridium difficile was detected in 35 samples (18.3%), and all isolates were toxigenic strains. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of each assay for detecting CDI were as follows: Quik Chek Complete CDT (45.7%, 100%, 100%, 89.1%), Quik Chek Complete GDH (97.1%, 99.4%, 97.1%, 99.4%), Xpert CD (94.3%, 100%, 100%, 98.7%), and toxigenic culture (91.4%, 100%, 100%, 98.1%). A two-step algorithm performed identically with Xpert CD assay. Our data showed that most C. difficile isolates from adult patients were toxigenic. We demonstrated that a two-step algorithm based on GDH/CDT assay followed by Xpert CD assay as a confirmatory test was rapid, reliable, and cost effective for diagnosis of CDI in an adult patient setting with high prevalence of toxigenic C. difficile. © 2017 Wiley Periodicals, Inc.
Full Text Available The occurrence of Clostridium difficile colitis is on the rise and has become more difficult to manage with standard therapy. Thus, the need for alternative treatments is essential. Tigecycline is a glycylcycline antibiotic that has been shown to be effective against C. difficile through several published case reports and in in vitro studies. We present a case of C. difficile colitis that failed to respond to metronidazole and oral vancomycin therapy, but improved on a combination of rifaximin, tigecycline, and vancomycin.
Carstensen, Jeppe West; Hansen, Axel Kornerup
Faecal transplantation as a treatment for Clostridium difficile infection, ulcerative colitis and the metabolic syndrome Faecal transplantation as a therapeutic tool is increasingly reported in the scientific literature. Faecal transplantation is currently becoming a treatment for nosocomial......, refractory infections with C. difficile. Furthermore, faecal transplantation has been suggested as a treatment for ulcerative colitis as well as for the metabolic syndrome. In the accumulated literature faecal transplantations appear to be safe, effective and superior to current treatments. Faecal...... transplantation remains a sparsely investigated treatment, however, especially for other diagnoses than C. difficile infection....
Soriano, Melinda M; Liao, Siyun; Danziger, Larry H
Fidaxomicin was approved for the treatment of Clostridium difficile infections in 2011. It has a novel mechanism of action and narrow spectrum of activity that makes it unique among the currently used therapies for this disease. Phase III clinical studies demonstrated a benefit of fidaxomicin over vancomycin for the outcomes of recurrence and global cure or sustained clinical response. This observation was confirmed within specific populations, including those of older age, immunocompromised due to active cancers, and patients taking concomitant antibiotics. Additionally, fidaxomicin significantly reduced recurrence rates compared to vancomycin among patients receiving treatment for recurrent C. difficile episodes. Fidaxomicin represents an advance in therapy for the treatment of C. difficile infections.
Angen, Øystein; Ahrens, Peter; Tegtmeier, Conny
Based on the 16S rRNA sequences of a collection of well-characterized strains of Haemophilus somnus a set of primers was selected as candidates for a species-specific PCR test. All investigated H. somnus strains were found positive in the test, including 12 strains earlier found to represent H....... somnus by DNA-DNA hybridization as well as representatives of the 16 ribotypes previously described within this species. The specificity of the test was evaluated on a broad collection of strains within the family Pasteurellaceae and on other Gram positive and negative species. None of these strains gave...... for identification of bacteria belonging to this phenotypically heterogeneous and often slow growing species....
Mar 30, 2012 ... The. cpDNA PCR-RFLP based genetic distance (GD) among 30 tea accessions ranged from 0 to 0.071, with the mean of 0.049. This study suggests that the optimization system was suitable for PCR-RFLP analysis of. cpDNA in tea. Key words: Camellia sinensis, PCR-RFLP, chloroplast DNA, establishment.
Full Text Available Introduction: Clostridium difficile is the most important definable cause of healthcare acquired diarrhea. Recommended treatments for Clostridium difficile infection (CDI are metronidazole, oral vancomycin and fidaxomicin (a new narrow spectrum macrocyclic antibiotic. Aim: The aim of this investigation was to review the treatment of CDI in Iran. Method: 1600 medical records and prescriptions were scrutinized for patients complaining of diarrhea, colitis and gastroenteritis. The therapeutic route was investigated in each individual case bearing in mind the medical and medication history as well as other co-morbidities. Results: The selection of antibiotic by many medical practitioners for the treatment of diarrhea, colitis and gastroenteritis were inappropriate and random. In most cases the chosen antibiotic, can itself be associated with initiation or worsening of CDI. Conclusion: The needs for antimicrobial stewardship program to preserve the effectiveness of current available therapies are strongly recommended. This program must focus on the overall reduction of inappropriate antibiotic prescribing and ultimately on enforcing the adherence to the reputable antibacterial guidelines.
Deng, Kai; Talukdar, Prabhat K; Sarker, Mahfuzur R; Paredes-Sabja, Daniel; Torres, J Antonio
Clostridium difficile is frequently found in meat and meat products. Germination efficiency, defined as colony formation, was previously investigated at temperatures found in meat handling and processing for spores of strain M120 (animal isolate), R20291 (human isolate), and DK1 (beef isolate). In this study, germination efficiency of these spore strains was assessed in phosphate buffered saline (PBS, a w ∼1.00), commercial beef jerky (a w ∼0.82/0.72), and a w -adjusted PBS (a w ∼0.82/0.72). Surface hydrophobicity was followed for spores stored in PBS. After three months and for all PBS a w levels tested, M120 and DK1 spores showed a ∼1 decimal reduction in colony formation but this was not the case when kept in beef jerky suggesting a protective food matrix effect. During storage, and with no significant a w effect, an increase in colony formation was observed for R20291 spores kept in PBS (∼2 decimal log increase) and beef jerky (∼1 decimal log increase) suggesting a loss of spore superdormancy. For all strains, no significant changes in spore surface hydrophobicity were observed after storage. Collectively, these results indicate that depending on the germination properties of C. difficile spores and the media properties, their germination efficiency may increase or decrease during long term food storage. Copyright © 2017 Elsevier Ltd. All rights reserved.
Full Text Available Toxic megacolon can be a form of severe clinical course of the infection with Clostridium difficile (ICD, life-threatening, requiring a particular course of treatment. Infection with Clostridium difficile in the Galati Infectious Disease Hospital presents rising number of cases, namely 172 cases in 2014, 271 cases in 2015 and 301 cases in 2016 with clinical evolutions with different severity degrees, including toxic megacolon and death. Among 744 patients with ICD in our clinic, since 1st January 2014 to 31 December 2016. The frequency of toxic megacolon (TM was 0,537%, so: 3 toxic megacolon cases with favorable evolution with treatment with vancomycin and metronidazole and just one case whose evolution was aggravated under this therapy and evolved favorably under treatment with tigecycline. The work presents this last case of ICD occurred in a 69 years old, immunocompetent man with unknown concomitant chronic diseases which undergoes surgery for bilateral inguinal hernia and receives antibiotherapy with cephalosporin IIIrd generation during surgery and after 7 days develops medium degree ICD with score Atlas 3 and receives therapy with oral vancomycin. He presents clinical aggravation during this therapy with the occurrence of colon dilatation, ascites and right pleurisy at ultrasound and therapy associated with metronidazole is decided. Clinical aggravation continues in this combined therapy with defining the clinical, colonoscopy and tomography criteria for TM and is decided surgical monitoring and replacing antibiotherapy with tigecycline. Evolution is favorable with tigecycline without surgical intervention.
Samie, Ahmed Abdel; Traub, Marc; Bachmann, Klaus; Kopischke, Karolin; Theilmann, Lorenz
Clostridium difficile associated disease (CDAD) is one of the most common causes of hospital-acquired diarrhea. Despite increasing incidence of clostridium difficile-associated diarrhea, there are few data on risk factors associated with its relapse. We studied retrospectively possible risk factors for the recurrence of CDAD; 124 patients fulfilled the criteria of CDAD during the study period between January 2006 and July 2009. After successful treatment, recurrence occurred in 20 patients. Nineteen patients (95%, p = 0.029) in the relapse group were on long term proton pump inhibitor therapy compared to 77 patients (74%) in the non-relapse group. There was no statistically significant difference in severity (CRP: p = 0.442, leucocytosis: p = 0.415) and length of hospitalization (p= 0.539) in both studied groups; however, CDAD-relapse was associated with more hospital readmissions and increased health care costs. Proton pump inhibitor therapy may be associated with increased risk of recurrence of CDAD, and represents a relevant, yet correctable risk factor. In patients at risk for CDAD, proton pump inhibitors should be used carefully.
Moon, Hee-Won; Kim, Hyeong Nyeon; Hur, Mina; Shim, Hee Sook; Kim, Heejung; Yun, Yeo-Min
Since every single test has some limitations for detecting toxigenic Clostridium difficile, multistep algorithms are recommended. This study aimed to compare the current, representative diagnostic algorithms for detecting toxigenic C. difficile, using VIDAS C. difficile toxin A&B (toxin ELFA), VIDAS C. difficile GDH (GDH ELFA, bioMérieux, Marcy-l'Etoile, France), and Xpert C. difficile (Cepheid, Sunnyvale, California, USA). In 271 consecutive stool samples, toxigenic culture, toxin ELFA, GDH ELFA, and Xpert C. difficile were performed. We simulated two algorithms: screening by GDH ELFA and confirmation by Xpert C. difficile (GDH + Xpert) and combined algorithm of GDH ELFA, toxin ELFA, and Xpert C. difficile (GDH + Toxin + Xpert). The performance of each assay and algorithm was assessed. The agreement of Xpert C. difficile and two algorithms (GDH + Xpert and GDH+ Toxin + Xpert) with toxigenic culture were strong (Kappa, 0.848, 0.857, and 0.868, respectively). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of algorithms (GDH + Xpert and GDH + Toxin + Xpert) were 96.7%, 95.8%, 85.0%, 98.1%, and 94.5%, 95.8%, 82.3%, 98.5%, respectively. There were no significant differences between Xpert C. difficile and two algorithms in sensitivity, specificity, PPV and NPV. The performances of both algorithms for detecting toxigenic C. difficile were comparable to that of Xpert C. difficile. Either algorithm would be useful in clinical laboratories and can be optimized in the diagnostic workflow of C. difficile depending on costs, test volume, and clinical needs.
Montoya Ramirez, Monica
Clostridium difficile has been Gram positive anaerobic bacillus producer of spores and recognized as the primary pathogen involved in nosocomial diarrhea in adults. Two toxins are produced: A and B, responsible for the symptoms present in patients with diseases associated to C. difficile (EACD) and regulated by the tcdC gene. Some variants also have had a binary toxin and changes in the regulatory gene, it is believed that these may lead to the overproduction of toxins and the consequent emergence of hypervirulent strains. The hypervirulent NAP1 was identified for the first time in Latin America (in addition to other traditional pulsotypes and other native), in the years 2008-2009 during the outbreak of nosocomial C. difficile diarrhea occurred in the Hospital San Juan de Dios in Costa Rica. In order to know whether this variant NAP1 or other pulsotypes are found present in other hospitals, C. difficile isolates obtained from patients in Hospital Mexico of Costa Rica were studied in the period October 2010-August 2012, in order to investigate molecularly by PCR toxins that are produced. Pulsotypes that belong are determined by pulsed-field electrophoresis, besides the minimum inhibitory concentration of ciprofloxacin, clindamycin, metronidazole, moxifloxacia, rifampin and vancomycin through the E-test technique. 56 strains isolates were analyzed in culture and identified as C. difficile by detection the tpi gene in the Hospital Mexico. The strains have had higher resistance to ciprofloxacin and clindamycin, 100% and 95%, respectively, clindamycin is the most related with associated diarrhea to antibiotic. In addition, significant percentages of resistance to moxifloxacin (43%) are obtained and rifampacin (43%) and all strains were sensitive to metronidazole and vancomycin. On the other hand, seven different patterns of PCR according to the locus SWAP were obtained, being the most frequent (58%, 33 strains) which corresponds to tcdA+, tcdB+, cdtB- and tcdC+ deletion
Evaluation of LIAISON® C. difficile glutamate dehydrogenase and LIAISON® C. difficile toxin A and B in Copan FecalSwabTM samples in a three-step algorithm for the diagnosis of Clostridium difficile infection
Full Text Available The presumptive laboratory diagnosis of Clostridium difficile infection is achieved by the means of the detection of a common antigen (glutamate dehydrogenase, GDH in stool, then confirming the positives either by the detection of toxins A and B or by a molecular test for the detection of pathogenicity locus, encoding for the two toxins and for the binary toxin. A fully automated chemiluminescence system for the GDH antigen (LIAISON® C. difficile GDH and for the detection of toxins A and B (LIAISON® C. difficile Toxin A and B (DiaSorin, Gerenzano, Italy allows for the performance of these tests on large numbers of samples in a short time, ensuring the traceability of the data.
Staheli, Jeannette P; Boyce, Richard; Kovarik, Dina; Rose, Timothy M
While PCR primer design for the amplification of known sequences is usually quite straightforward, the design, and successful application of primers aimed at the detection of as yet unknown genes is often not. The search for genes that are presumed to be distantly related to a known gene sequence, such as homologous genes in different species, paralogs in the same genome, or novel pathogens in diverse hosts, often turns into the proverbial search for the needle in the haystack. PCR-based methods commonly used to address this issue involve the use of either consensus primers or degenerate primers, both of which have significant shortcomings regarding sensitivity and specificity. We have developed a novel primer design approach that diminishes these shortcomings and instead takes advantage of the strengths of both consensus and degenerate primer designs, by combining the two concepts into a Consensus-Degenerate Hybrid Oligonucleotide Primer (CODEHOP) approach. CODEHOP PCR primers contain a relatively short degenerate 3' core and a 5' nondegenerate clamp. The 3' degenerate core consists of a pool of primers containing all possible codons for a 3-4 aminoacid motif that is highly conserved in multiply aligned sequences from known members of a protein family. Each primer in the pool also contains a single 5' nondegenerate nucleotide sequence derived from a codon consensus across the aligned aminoacid sequences flanking the conserved motif. During the initial PCR amplification cycles, the degenerate core is responsible for specific binding to sequences encoding the conserved aminoacid motif. The longer consensus clamp region serves to stabilize the primer and allows the participation of all primers in the pool in the efficient amplification of products during later PCR cycles. We have developed an interactive web site and algorithm (iCODEHOP) for designing CODEHOP PCR primers from multiply aligned protein sequences, which is freely available online. Here, we describe the
Wieczorkiewicz, Jeffrey T; Lopansri, Bert K; Cheknis, Adam; Osmolski, James R; Hecht, David W; Gerding, Dale N; Johnson, Stuart
Antibiotics have been shown to influence the risk of infection with specific Clostridium difficile strains as well as the risk of C. difficile infection (CDI). We performed a retrospective case-control study of patients infected with the epidemic BI/NAP1/027 strain in a U.S. hospital following recognition of increased CDI severity and culture of stools positive by C. difficile toxin immunoassay. Between 2005 and 2007, 72% (103/143) of patients with first-episode CDIs were infected with the BI strain by restriction endonuclease analysis (REA) typing. Most patients received multiple antibiotics within 6 weeks of CDI onset (median of 3 antibiotic classes). By multivariate analysis, fluoroquinolone and macrolide exposure was more frequent among BI cases than among non-BI-infected controls (odds ratio [OR] for fluoroquinolones, 3.2; 95% confidence interval [CI], 1.3 to 7.5; (P Fluoroquinolone use, macrolide use, and C. difficile resistance to these antibiotic classes were associated with infection by the epidemic BI strain of C. difficile in a U.S. hospital during a time when CDI rates were increasing nationally due to the highly fluoroquinolone-resistant BI/NAP1/027 strain. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Carlos Augusto de Oliveira Júnior
Full Text Available ABSTRACT: The present study aimed to evaluate five non-toxigenic strains of Clostridium difficile (NTCD in vitro and to select one strain to prevent C. difficile (CDI infection in hamsters ( Mesocricetus auratus . The NTCD strains were evaluated for spore production in vitro, antimicrobial susceptibility and presence of antimicrobial resistance genes. Approximately 107 spores of the selected strain (Z31 were administered by esophageal gavage in hamsters pretreated with 30mg kg-1 of clindamycin. The challenge with a toxigenic strain of C. difficile was conducted at 36 and 72h, and the animals were observed for 28 days. The NTCD strain of C. difficile (Z31 was able to prevent CDI in all animals that received it.
Carstensen, Jeppe West; Hansen, Axel Kornerup
Faecal transplantation as a treatment for Clostridium difficile infection, ulcerative colitis and the metabolic syndrome Faecal transplantation as a therapeutic tool is increasingly reported in the scientific literature. Faecal transplantation is currently becoming a treatment for nosocomial...
Rasmussen, Torsten Bloch; Friis, Mikkel Lønborg; Lehnhoff, Rudolf
severe colonic dilation, inflammation and oedema consistent with toxic megacolon. Stool samples were positive for Clostridium difficile. Oral vancomycine treatment and colonic decompression were inefficient. Subtotal colectomy was performed after which the condition improved. Udgivelsesdato: 2008-May-5...
Debast, Sylvia Brigitte
Since a decade, Clostridium difficile infection (CDI) has increased progressively in incidence and severity of disease. Currently, CDI is considered the leading cause of nosocomial diarrhoea, associated with an increased duration of hospitalization, healthcare expenses, morbidity and mortality.
Fitzpatrick Leo R
Full Text Available Abstract Background Probiotics have beneficial effects in rodent models of Clostridium difficile (C. diffiicle-induced colitis. The spore forming probiotic strain Bacillus Coagulans GBI-30, 6086 (BC30 has demonstrated anti-inflammatory and immune-modulating effects in vitro. Our goal was to determine if BC30 improved C. difficile-induced colitis in mice. Starting on study day 0, female C57BL/6 mice were dosed by oro-gastric gavage for 15 days with vehicle (saline or BC30 (2 × 109 CFU per day. Mice in the C. difficile groups received an antibiotic mixture (study days 5 to 8 in the drinking water, and clindamycin (10 mg/kg, i.p., on study day 10. The C. difficile strain VPI 10463 was given by gavage at 104 CFU to induce colitis on day 11. On day 16, stools and colons were collected for further analyses. Results All mice treated with BC30 survived on study day 13, while two mice treated with vehicle did not survive. On day 12, a significant difference (p = 0.0002 in the percentage of mice with normal stools (66.7% was found in the BC30/C. difficile group, as compared to the vehicle/C. diffcile group (13.0%. On study day 16, 23.8% of mice treated with BC30 had normal stools, while this value was 0% with vehicle treatment (p value = 0.0187. On this day, the stool consistency score for the BC30/C. difficile group (1.1 ± 0.2 was significantly lower (p C. difficile cohort (1.9 ± 0.2. BC30 modestly attenuated the colonic pathology (crypt damage, edema, leukocyte influx that was present following C. difficile infection. Colonic MIP-2 chemokine contents (pg/2 cm colon were: 10.2 ± 0.5 (vehicle/no C. difficile, 24.6 ± 9.5 (vehicle/C. difficile and 16.3 ± 4.3 (BC30/C. difficle. Conclusion The probiotic BC30 improved some parameters of C. difficile-induced colitis in mice. BC30 prolonged the survival of C. diffiicle infected mice. Particularly, this probiotic improved the stool consistency of mice, in this infectious colitis model.
Zhu, Yu; Wang, Li; Feng, Shana; Wang, Shuai; Zheng, Cuiling; Wang, Jingzhi; Du, Chunxia; Feng, Yun; Li, Dan; Shi, Yuankai; Han, Xiaohong
The aim of this study was to investigate the prevalence of Clostridium difficile (C. difficile) infection and the risk factors for acquisition of C. difficile-associated diarrhea (CDAD) among cancer patients who received chemotherapy or radiation therapy. We analyzed 277 stool samples from cancer patients with diarrhea between Sep 2010 and Dec 2011 in our hospital. Stool C. difficile toxin A/B test, stool culture for C. difficile and routine stool examination were performed. In addition, the risk factors for CDAD were investigated in a set of 41 C. difficile toxin-positive cancer patients and 82 matched C. difficile toxin-negative controls by univariate analysis and multivariate analysis. Out of a total of 277 cancer patients with diarrhea, 41 (14.8%) were C. difficile toxin-positive. Among these 41 cases, 11 (26.8%, 11/41) were C. difficile culture-positive. Univariate analysis showed that antibiotics use (P = 0.853), proton pump inhibitor use (P = 0.718), hypoproteinemia (P = 0.139) and white blood cell count (P = 0.454) did not appear to be associated with acquisition of CDAD in cancer patients. However, receiving chemotherapy (P = 0.023), receiving radiotherapy (P = 0.003), a positive fecal occult blood test result (P = 0.005) and the presence of fecal leukocytes (P = 0.007) showed close association with acquisition of CDAD in cancer patients. Multivariate analysis showed that receiving chemotherapy (OR, 8.308; 95% CI, 1.997-34.572; P = 0.004) and a positive result of fecal occult blood test (OR, 8.475; 95% CI, 1.463-49.109; P = 0.017) were independent risk factors for acquisition of CDAD among cancer patients. Our results support that receiving chemotherapy and a positive fecal occult blood test result are independent risk factors for acquisition of CDAD among cancer patients. Cancer patients who are at high-risk for CDAD should take stool C. difficile toxin A/B test and stool culture for C. difficile regularly and prevention of CDAD.
Kondepudi, Kanthi Kiran; Ambalam, Padma; Karagin, Peren H; Nilsson, Ingrid; Wadström, Torkel; Ljungh, Åsa
The protective effect of a multi-strain probiotic and synbiotic formulation was evaluated in C57BL/6 mice infected with Clostridium difficile (CD) NAP1/027. Antibiotic-treated mice were divided into the following four groups: Group 1, fed with a synbiotic formulation consisting of Lactobacillus plantarum F44, L. paracasei F8, Bifidobacterium breve 46, B. lactis 8:8, galacto-oligosaccharides, isomalto-oligosaccharides, and resistant starch; Group 2, fed with the same four probiotic strains as Group 1; Group 3, fed with the same prebiotic supplements as Group 1 for 7 days before CD infection; and Group 4 (control group) antibiotic treated and infected with NAP1/027 strain. Feces and cecal contents were collected for microbial cell viability, quantitative PCR (qPCR), toxin analyses and histopathology. Synbiotics- and probiotics-fed mice showed a significant increase in total bifidobacteria (P probiotic formulation confers protection against NAP1/027 infection in C57BL/6 mice. This holds promise for performing human studies. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.
Lim, Su-Chen; Foster, Niki F; Riley, Thomas V
Clostridium difficile is an important enteric pathogen of humans and food animals. Recently it has been isolated from retail foods with prevalences up to 42%, prompting concern that contaminated foods may be one of the reasons for increased community-acquired C. difficile infection (CA-CDI). A number of studies have examined the prevalence of C. difficile in raw meats and fresh vegetables; however, fewer studies have examined the prevalence of C. difficile in ready-to-eat meat. The aim of this study was to investigate the in vitro susceptibility of 11 C. difficile isolates of food animal and retail food origins to food preservatives commonly used in ready-to-eat meats. The broth microdilution method was used to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for sodium nitrite, sodium nitrate and sodium metabisulphite against C. difficile. Checkerboard assays were used to investigate the combined effect of sodium nitrite and sodium nitrate, commonly used in combination in meats. Modal MIC values for sodium nitrite, sodium nitrate and sodium metabisulphite were 250 μg/ml, >4000 μg/ml and 1000 μg/ml, respectively. No bactericidal activity was observed for all three food preservatives. The checkerboard assays showed indifferent interaction between sodium nitrite and sodium nitrate. This study demonstrated that C. difficile can survive in the presence of food preservatives at concentrations higher than the current maximum permitted levels allowed in ready-to-eat meats. The possibility of retail ready-to-eat meats contaminated with C. difficile acting as a source of CDI needs to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.
Peltier, Johann; Courtin, Pascal; El Meouche, Imane; Catel-Ferreira, Manuella; Chapot-Chartier, Marie-Pierre; Lemée, Ludovic; Pons, Jean-Louis
Primary antibiotic treatment of Clostridium difficile intestinal diseases requires metronidazole or vancomycin therapy. A cluster of genes homologous to enterococcal glycopeptides resistance vanG genes was found in the genome of C. difficile 630, although this strain remains sensitive to vancomycin. This vanG-like gene cluster was found to consist of five ORFs: the regulatory region consisting of vanR and vanS and the effector region consisting of vanG, vanXY and vanT. We found that 57 out of 83 C. difficile strains, representative of the main lineages of the species, harbour this vanG-like cluster. The cluster is expressed as an operon and, when present, is found at the same genomic location in all strains. The vanG, vanXY and vanT homologues in C. difficile 630 are co-transcribed and expressed to a low level throughout the growth phases in the absence of vancomycin. Conversely, the expression of these genes is strongly induced in the presence of subinhibitory concentrations of vancomycin, indicating that the vanG-like operon is functional at the transcriptional level in C. difficile. Hydrophilic interaction liquid chromatography (HILIC-HPLC) and MS analysis of cytoplasmic peptidoglycan precursors of C. difficile 630 grown without vancomycin revealed the exclusive presence of a UDP-MurNAc-pentapeptide with an alanine at the C terminus. UDP-MurNAc-pentapeptide [d-Ala] was also the only peptidoglycan precursor detected in C. difficile grown in the presence of vancomycin, corroborating the lack of vancomycin resistance. Peptidoglycan structures of a vanG-like mutant strain and of a strain lacking the vanG-like cluster did not differ from the C. difficile 630 strain, indicating that the vanG-like cluster also has no impact on cell-wall composition.
Full Text Available Rahul Pathak,1 Hill Ambrose Enuh,1 Anish Patel,1 Prasanna Wickremesinghe21Department of Internal Medicine, New York Medical College, Internal Medicine Program at Richmond University Medical Center, Staten Island, NY, USA; 2Department of Gastrointestinal Medicine, New York Medical College, Internal Medicine Program at Richmond University Medical Center, Staten Island, NY, USABackground: Clostridium difficile infection (CDI has become a global concern over the last decade. In the United States, CDI escalated in incidence from 1996 to 2005 from 31 to 64/100,000. In 2010, there were 500,000 cases of CDI with an estimated mortality up to 20,000 cases a year. The significance of this problem is evident from the hospital costs of over 3 billion dollars annually. Fecal microbiota transplant (FMT was first described in 1958 and since then about 500 cases have been published in literature in various small series and case reports. This procedure has been reported mainly from centers outside of the United States and acceptance of the practice has been difficult. Recently the US Food and Drug Administration (FDA labeled FMT as a biological drug; as a result, guidelines will soon be required to help establish it as a mainstream treatment. More US experience needs to be reported to popularize this procedure here and form guidelines.Method: We did a retrospective review of our series of patients with relapsing CDI who were treated with FMT over a 3-year period. We present our experience with FMT at a community hospital as a retrospective review and describe our procedure.Results: There were a total of 12 patients who underwent FMT for relapsing C. difficile. Only one patient failed to respond and required a second FMT. There were no complications associated with the transplant and all patients had resolution of symptoms within 48 hours of FMT.Conclusion: FMT is a cheap, easily available, effective therapy for recurrent CDI; it can be safely performed in a
Dhalluin, Anne; Bourgeois, Ingrid; Pestel-Caron, Martine; Camiade, Emilie; Raux, Gregory; Courtin, Pascal; Chapot-Chartier, Marie-Pierre; Pons, Jean-Louis
A gene encoding a putative peptidoglycan hydrolase was identified by sequence similarity searching in the Clostridium difficile 630 genome sequence, and the corresponding protein, named Acd (autolysin of C. difficile) was expressed in Escherichia coli. The deduced amino acid sequence of Acd shows a modular structure with two main domains: an N-terminal domain exhibiting repeated sequences and a C-terminal catalytic domain. The C-terminal domain exhibits sequence similarity with the glucosaminidase domains of Staphylococcus aureus Atl and Bacillus subtilis LytD autolysins. Purified recombinant Acd produced in E. coli was confirmed to be a cell-wall hydrolase with lytic activity on the peptidoglycan of several Gram-positive bacteria, including C. difficile. The hydrolytic specificity of Acd was studied by RP-HPLC analysis and MALDI-TOF MS using B. subtilis cell-wall extracts. Muropeptides generated by Acd hydrolysis demonstrated that Acd hydrolyses peptidoglycan bonds between N-acetylglucosamine and N-acetylmuramic acid, confirming that Acd is an N-acetylglucosaminidase. The transcription of the acd gene increased during vegetative cellular growth of C. difficile 630. The sequence of the acd gene appears highly conserved in C. difficile strains. Regarding deduced amino acid sequences, the C-terminal domain with enzymic function appears to be the most conserved of the two main domains. Acd is the first known autolysin involved in peptidoglycan hydrolysis of C. difficile.
Mizui, T; Teramachi, H; Tachi, T; Tamura, K; Shiga, H; Komada, N; Umeda, M; Koda, A; Aoyama, S; Goto, C; Tsuchiya, T
Measures for prevention of Clostridium difficile-associated diarrhea, a common nosocomial infection, in hospital settings are urgently needed. This study was conducted to identify the risk factors contributing to C. difficile-associated diarrhea and to evaluate the clinical benefit of probiotics in its prevention. The study included 2716 patients at least 20 years old who received an injected antibiotic at any time between February 2010 and February 2011; a total of 2687 patients (98.9%) were assigned to the non-C. difficile-associated diarrhea group, and 29 patients (1.1%) were assigned to the C. difficile-associated diarrhea group. Univariate analysis revealed a significant difference between the two groups for the following factors: antibiotic therapy for > or = 8 days; enteral nutrition; intravenous hyperalimentation; fasting; proton pump inhibitor use; H2 blocker use; and serum albumin or = 8 days, intravenous hyperalimentation, proton pump inhibitor use, and H2 blocker use were therefore shown to be risk factors for C. difficile-associated diarrhea. Prophylactic probiotic therapy was not shown to suppress the occurrence of C. difficile-associated diarrhea.
Full Text Available Clostridium difficile is the leading cause of hospital acquired diarrhoea in industrialised countries. Under conditions that are not favourable for growth, the pathogen produces metabolically dormant endospores via asymmetric cell division. These are extremely resistant to both chemical and physical stress and provide the mechanism by which C. difficile can evade the potentially fatal consequences of exposure to heat, oxygen, alcohol, and certain disinfectants. Spores are the primary infective agent and must germinate to allow for vegetative cell growth and toxin production. While spore germination in Bacillus is well understood, little is known about C. difficile germination and outgrowth. Here we use genome-wide transcriptional analysis to elucidate the temporal gene expression patterns in C. difficile 630 endospore germination. We have optimized methods for large scale production and purification of spores. The germination characteristics of purified spores have been characterized and RNA extraction protocols have been optimized. Gene expression was highly dynamic during germination and outgrowth, and was found to involve a large number of genes. Using this genome-wide, microarray approach we have identified 511 genes that are significantly up- or down-regulated during C. difficile germination (p≤0.01. A number of functional groups of genes appeared to be co-regulated. These included transport, protein synthesis and secretion, motility and chemotaxis as well as cell wall biogenesis. These data give insight into how C. difficile re-establishes its metabolism, re-builds the basic structures of the vegetative cell and resumes growth.
Full Text Available Clostridium difficile is the most common cause of nosocomial diarrhea. It is usually a consequence of antibiotic treatment, But sporadic cases can occur. This study was aimed to determine the frequency of the nosocomial Clostridium difficile (C. difficile associated diarrhea in Tehran University of Medical Sciences hospitals and study of antibacterial susceptibility of isolates. In this study a total of 942 stool samples from patients with nosocomial diarrhea that were hospitalized in Imam Khomeini hospital, Shariati hospital and Children clinical center were collected. The samples were cultured on a selective cycloserine cefoxitin fructose agar (CCFA and incubated in anaerobic conditions, at 37°C for 5 days. Isolates were characterized to species level by conventional biochemical tests. Bacterial cytotoxicity was assayed on tissue culture (vero. Antimicrobial sensitivity of isolated toxigenic C. difficile were investigated by kirby Beuer method (disk diffusion. Our findings show that, of the total patients, 57 toxigenic C. difficile (6.1% were isolated. Results of statistical analysis show significant differences between the rate of isolated toxigenic C. difficile and age group of patients (P
Kim, K.H.; Fekety, R.; Batts, D.H.; Brown, D.; Cudmore, M.; Silva, J. Jr.; Waters, D.
Clostridium difficile is the most important cause of antibiotic-associated colitis, but its epidemiology remains unknown. Using a selective medium for the isolation of C. difficile, cultures were obtained from the environment and contacts of hospitalized patients carrying C. difficile in their stools. In areas where carriers had diarrhea, 85 (9.3%) of 910 cultures of floors and other surfaces, especially those subject to fecal contamination, were positive. In areas where there were no known carriers, only 13 (2.6%) of 497 cultures of similar sites were positive (P less than 0.005). C difficile was isolated from hands and stools of asymptomatic hospital personnel, from sewage and soil, and from the home of a patient. Environmental isolates were toxigenic. C. difficile inoculated onto a floor persisted there for five months. Further studies are needed to document how often floor persisted there for five months. Further studies are needed to document how often C. difficile shed by patients with antibiotic-associated colitis is acquired by other persons and whether isolation precautions are capable of limiting the organism's spread.
Reller, Megan E; Alcabasa, Romina C; Lema, Clara A; Carroll, Karen C
We compared 3 rapid assays for Clostridium difficile with a cell culture cytotoxicity neutralization assay (CCNA). Of 600 stool samples, 46 were positive for toxigenic C difficile. Both rapid common antigen assays were highly sensitive (91.3%-100%) and, therefore, were appropriate screening tests. The rapid toxin assay had poor sensitivity (61%) but excellent specificity (99.3%). Testing stools for glutamate dehydrogenase (step 1) and those positive with a rapid toxin assay (step 2) would correctly classify 81% of submitted specimens within 2 hours, including during periods of limited staffing (evenings, nights, and weekends). CCNA could then be used as a third step to test rapid toxin-negative samples, thereby providing a final result for the remaining 19% of samples by 48 to 72 hours. The use of rapid assays as outlined could enhance timely diagnosis of C difficile.
Full Text Available Background. A national project on Clostridium difficile infection (CDI, funded by the Center for Prevention and Control of Diseases of Italian Ministry of Health, was performed in 2012-2013. Microbiological laboratories of the National Public Heath System were invited by the Istituto Superiore di Sanità to provide information on CDI diagnostics through a closed answer questionnaire. Materials and Methods. In total, 14 regions and the independent province of Trento participated in and 278 filled questionnaires were sent back. The data obtained indicate that 87% of the laboratories routinely perform diagnostic assays for C. difficile. GDH detection is used as the first screening test by 33% of these laboratories. Most of them declared to use toxins enzyme immunoassays (88%, whereas a minority performs C. difficile culture (26% or molecular assays (19%. Only 37% of the laboratories stated to adopt a diagnostic algorithm. The algorithms adopted are different and high heterogeneity in the combination of the assays used was observed. Results. Fifty eight percent of laboratories declared to type C. difficile strains, the majority (82% sending faecal samples or strains to a reference laboratory. Sixty-two laboratories, routinely performing C. difficile culture, were invited by ISS to send five isolates for molecular typing. In total, 103 isolates from 22 hospitals were collected and 31 different PCR-ribotypes were identified. PCR-ribotype 356/607 was the most frequent (27%, followed by 018 (12% and 027 (8%. The latter is a worldwide spread hypervirulent type only recently emerged in our country. A molecular characterization of the different PCR-ribotypes detected was also performed by Xpert® C. difficile. Conclusions. The study highlights the need for a more careful selection of diagnostic algorithms to improve CDI diagnosis and the urgency to implement a National Surveillance of CDI in Italy.
The French law imposes in some situations the presence of a person skilled in radiation protection (PCR). This article describes the cases when this person must belong to the staff of the enterprise or when this person may be sub-contracted. For instance in most nuclear facilities the PCR must be on the payroll, for enterprises dedicated to nuclear transport the PCR's job can be sub-contracted. A decision given by the ASN (French Nuclear Safety Authority) sets the minimal requests (in terms of training, job contract, activities) of the sub-contracted PCR. (A.C.)
Full Text Available We present the case of a 58-year-old man who underwent urgent blowhole colostomy for toxic megacolon (TM secondary to Clostridium difficile infection (CDI. This infection occurred under antibiotic coverage with amoxicillin-clavulanic acid, four days after laparoscopic sigmoidectomy in our hospital. Although prospective clinical research regarding the surgical management of TM is lacking, decompressive procedures like blowhole colostomy are reported to carry a high risk of postoperative morbidity and mortality and are widely regarded as obsolete. Subtotal or total colectomy with end ileostomy is currently considered the procedure of choice. After presenting our case, we discuss the literature available on the subject to argue that the scarce evidence on the optimal surgical treatment for TM is primarily based on TM associated with inflammatory bowel diseases (IBD and that there might be a rationale for considering minimally invasive procedures like blowhole colostomy for CDI-associated TM.
Goldberg, Elad; Bishara, Jihad
Clostridium difficile-associated diarrhea (CDAD) is the most common documented cause of nosocomial diarrhea in developed countries. In recent years morbidity and mortality associated with this pathogen have increased significantly, simultaneously with the appearance of a new strain--NAP1/BI/027--which was implicated in epidemics of severe disease in hospitals around the world. Despite the accumulated experience in identification and treatment of patients, physicians continue to face complicated problems concerning the diagnosis, treatment and prevention of CDAD. However, significant effort is invested in the development of more accurate diagnostic tests, newer drugs for treatment and new methods to prevent the spread of the pathogen. The problems related to CDAD and updated possible solutions are discussed in this article.
Pruitt, Rory N.; Chumbler, Nicole M.; Rutherford, Stacey A.; Farrow, Melissa A.; Friedman, David B.; Spiller, Ben; Lacy, D. Borden (Vanderbilt)
The principle virulence factors in Clostridium difficile pathogenesis are TcdA and TcdB, homologous glucosyltransferases capable of inactivating small GTPases within the host cell. We present crystal structures of the TcdA glucosyltransferase domain in the presence and absence of the co-substrate UDP-glucose. Although the enzymatic core is similar to that of TcdB, the proposed GTPase-binding surface differs significantly. We show that TcdA is comparable with TcdB in its modification of Rho family substrates and that, unlike TcdB, TcdA is also capable of modifying Rap family GTPases both in vitro and in cells. The glucosyltransferase activities of both toxins are reduced in the context of the holotoxin but can be restored with autoproteolytic activation and glucosyltransferase domain release. These studies highlight the importance of cellular activation in determining the array of substrates available to the toxins once delivered into the cell.
Barreda Prades, Balma
Clostridium difficile es la causa más común de diarrea asociada a hospitales y antimicrobianos en los seres humanos, sin embargo, el papel de C. difficile en perros diarreicos no está definido. Los objetivos del presente trabajo son: Determinar la prevalencia de C. difficile en perros con y sin diarrea y comparar si hay diferencias entre perros hospitalizados y sanos. Analizar si la infección por C. difficile está relacionada con el uso de antibióticos u otros fármacos en perros y determinar ...
Lucy A Jury
Full Text Available BACKGROUND: Recent reports suggest that community-associated Clostridium difficile infection (CDI (i.e., no healthcare facility admission within 90 days may be increasing in frequency. We hypothesized that outpatient clinics could be an important source for acquisition of community-associated CDI. METHODS: We performed a 6-month prospective study of CDI patients to determine frequency of and risk factors for skin and environmental shedding during outpatient visits and to derive a prediction rule for positive cultures. We performed a point-prevalence culture survey to assess the frequency of C. difficile contamination in outpatient settings and evaluated the frequency of prior outpatient visits in patients with community-associated CDI. RESULTS: Of 67 CDI patients studied, 54 (81% had 1 or more outpatient visits within 12 weeks after diagnosis. Of 44 patients cultured during outpatient visits, 14 (32% had skin contamination and 12 (27% contaminated environmental surfaces. Decreased mobility, fecal incontinence, and treatment with non-CDI antibiotics were associated with positive cultures, whereas vancomycin taper therapy was protective. In patients not on CDI therapy, a prediction rule including incontinence or decreased mobility was 90% sensitive and 79% specific for detection of spore shedding. Of 84 clinic and emergency department rooms cultured, 12 (14% had 1 or more contaminated environmental sites. For 33 community-associated CDI cases, 31 (94% had an outpatient visit during the 12 weeks prior to onset of diarrhea. CONCLUSIONS: Patients with recent CDI present a significant risk for transmission of spores during outpatient visits. The outpatient setting may be an underappreciated source of community-associated CDI cases.
David A Burns
Full Text Available Clostridium difficile is the leading cause of antibiotic-associated diarrhoea and a major burden to healthcare services worldwide. In recent years, C. difficile strains belonging to the BI/NAP1/027 type have become highly represented among clinical isolates. These so-called 'hypervirulent' strains are associated with outbreaks of increased disease severity, higher relapse rates and an expanded repertoire of antibiotic resistance. Spores, formed during sporulation, play a pivotal role in disease transmission and it has been suggested that BI/NAP1/027 strains are more prolific in terms of sporulation in vitro than 'non-epidemic' C. difficile types. Work in our laboratory has since provided credible evidence to the contrary suggesting that the strain-to-strain variation in C. difficile sporulation characteristics is not type-associated. However, the BI/NAP1/027 type is still widely stated to have an increased rate of sporulation. In this study, we analysed the sporulation rates of 53 C. difficile strains, the largest sample size used to-date in such a study, including 28 BI/NAP1/027 isolates. Our data confirm that significant variation exists in the rate at which different C. difficile strains form spores. However, we clearly show that the sporulation rate of the BI/NAP1/027 type was no higher than that of non-BI/NAP1/027 strains. In addition, we observed substantial variation in sporulation characteristics within the BI/NAP1/027 type. This work highlights the danger of assuming that all strains of one type behave similarly without studying adequate sample sizes. Furthermore, we stress the need for more rigorous experimental procedures in order to quantify C. difficile sporulation more accurately in the future.
Wu, Xiaoqian; Cherian, Philip T.; Lee, Richard E.; Hurdle, Julian G.
Objectives The stationary phase of Clostridium difficile, which is primarily responsible for diarrhoeal symptoms, is refractory to antibiotic killing. We investigated whether disrupting the functions of the clostridial membrane is an approach to control C. difficile infections by promptly removing growing and non-growing cells. Methods The bactericidal activities of various membrane-active agents were determined against C. difficile logarithmic-phase and stationary-phase cultures and compared with known antibiotics. Their effects on the synthesis of ATP, toxins A/B and sporulation were also determined. The effect of rodent caecal contents on anti-difficile activities was examined using two reutericyclin lead compounds, clofazimine, daptomycin and other comparator antibiotics. Results Most membrane-active agents and partially daptomycin showed concentration-dependent killing of both logarithmic-phase and stationary-phase cultures. The exposure of cells to compounds at their MBC resulted in a rapid loss of viability with concomitant reductions in cellular ATP, toxins A/B and spore numbers. With the exception of nisin, these effects were not due to membrane pore formation. Interestingly, the activity of the proton ionophore nigericin significantly increased as the growth of C. difficile decreased, suggesting the importance of the proton gradient to the survival of non-growing cells. The activities of the lipophilic antimicrobials reutericyclins and clofazimine were reduced by caecal contents. Conclusions These findings indicate that C. difficile is uniquely susceptible to killing by molecules affecting its membrane function and bioenergetics, indicating that the clostridial membrane is a novel antimicrobial target for agents to alleviate the burden of C. difficile infections. PMID:23264511
Adams, Hannah M; Li, Xiang; Mascio, Carmela; Chesnel, Laurent; Palmer, Kelli L
Clostridium difficile infection (CDI) is an urgent public health concern causing considerable clinical and economic burdens. CDI can be treated with antibiotics, but recurrence of the disease following successful treatment of the initial episode often occurs. Surotomycin is a rapidly bactericidal cyclic lipopeptide antibiotic that is in clinical trials for CDI treatment and that has demonstrated superiority over vancomycin in preventing CDI relapse. Surotomycin is a structural analogue of the membrane-active antibiotic daptomycin. Previously, we utilized in vitro serial passage experiments to derive C. difficile strains with reduced surotomycin susceptibilities. The parent strains used included ATCC 700057 and clinical isolates from the restriction endonuclease analysis (REA) groups BI and K. Serial passage experiments were also performed with vancomycin-resistant and vancomycin-susceptible Enterococcus faecium and Enterococcus faecalis. The goal of this study is to identify mutations associated with reduced surotomycin susceptibility in C. difficile and enterococci. Illumina sequence data generated for the parent strains and serial passage isolates were compared. We identified nonsynonymous mutations in genes coding for cardiolipin synthase in C. difficile ATCC 700057, enoyl-(acyl carrier protein) reductase II (FabK) and cell division protein FtsH2 in C. difficile REA type BI, and a PadR family transcriptional regulator in C. difficile REA type K. Among the 4 enterococcal strain pairs, 20 mutations were identified, and those mutations overlap those associated with daptomycin resistance. These data give insight into the mechanism of action of surotomycin against C. difficile, possible mechanisms for resistance emergence during clinical use, and the potential impacts of surotomycin therapy on intestinal enterococci. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Travis J Kochan
Full Text Available Clostridium difficile (C. difficile is an anaerobic gram-positive pathogen that is the leading cause of nosocomial bacterial infection globally. C. difficile infection (CDI typically occurs after ingestion of infectious spores by a patient that has been treated with broad-spectrum antibiotics. While CDI is a toxin-mediated disease, transmission and pathogenesis are dependent on the ability to produce viable spores. These spores must become metabolically active (germinate in order to cause disease. C. difficile spore germination occurs when spores encounter bile salts and other co-germinants within the small intestine, however, the germination signaling cascade is unclear. Here we describe a signaling role for Ca2+ during C. difficile spore germination and provide direct evidence that intestinal Ca2+ coordinates with bile salts to stimulate germination. Endogenous Ca2+ (released from within the spore and a putative AAA+ ATPase, encoded by Cd630_32980, are both essential for taurocholate-glycine induced germination in the absence of exogenous Ca2+. However, environmental Ca2+ replaces glycine as a co-germinant and circumvents the need for endogenous Ca2+ fluxes. Cd630_32980 is dispensable for colonization in a murine model of C. difficile infection and ex vivo germination in mouse ileal contents. Calcium-depletion of the ileal contents prevented mutant spore germination and reduced WT spore germination by 90%, indicating that Ca2+ present within the gastrointestinal tract plays a critical role in C. difficile germination, colonization, and pathogenesis. These data provide a biological mechanism that may explain why individuals with inefficient intestinal calcium absorption (e.g., vitamin D deficiency, proton pump inhibitor use are more prone to CDI and suggest that modulating free intestinal calcium is a potential strategy to curb the incidence of CDI.
Full Text Available Purpose: Recurrent diarrhoea after successful treatment of primary Clostridium difficile associated disease (CDAD occurs due to bowel flora alterations and failure to mount an effective antibody response. Apart from antibiotics, risk factors include immunosuppressive and acid-suppressive drug administration. Biotherapeutics such as probiotic and epidermal growth factor (EGF may offer potential effective therapy for CDAD. Materials and Methods: The effect of biotherapeutics in mounting an antibody response against C. difficile toxins was studied in BALB/c mice challenged with C. difficile after pre-treatment with ampicillin, lansoprazole or cyclosporin. Sera from sacrificed animals were estimated for antitoxin IgG by enzyme linked immunosorbent assay. Results: Antitoxin IgG was significantly higher (P0.05 in animals in which C. difficile was given after pre-treatment with cyclosporin compared to those without any pre-treatment, or pre-treatment with antibiotic or lansoprazole. In inter-subgroup comparisons also significant anomaly in production of antitoxin IgG was found. The antitoxin IgG levels were raised in animals administered C. difficile after pre-treatment with ampicillin, but lower in animals administered cyclosporin. High levels of antitoxin IgG were also found in the serum samples of animals receiving lansoprazole and C. difficile. Conclusions: Probiotics showed their beneficial effect by boosting the immune response as seen by production of antitoxin IgG. Oral administration of EGF did not affect the immune response to C. difficile toxins as significant increase was not observed in the serum antitoxin IgG levels in any of the groups investigated.
Shaban, Lamyaa; Chen, Ying; Fasciano, Alyssa C; Lin, Yinan; Kaplan, David L; Kumamoto, Carol A; Mecsas, Joan
Endospore-forming Clostridioides difficile is a causative agent of antibiotic-induced diarrhea, a major nosocomial infection. Studies of its interactions with mammalian tissues have been hampered by the fact that C. difficile requires anaerobic conditions to survive after spore germination. We recently developed a bioengineered 3D human intestinal tissue model and found that low O 2 conditions are produced in the lumen of these tissues. Here, we compared the ability of C. difficile spores to germinate, produce toxin and cause tissue damage in our bioengineered 3D tissue model versus in a 2D transwell model in which human cells form a polarized monolayer. 3D tissue models or 2D polarized monolayers on transwell filters were challenged with the non-toxin producing C. difficile CCUG 37787 serotype X (ATCC 43603) and the toxin producing UK1 C. difficile spores in the presence of the germinant, taurocholate. Spores germinated in both the 3D tissue model as well as the 2D transwell system, however toxin activity was significantly higher in the 3D tissue models compared to the 2D transwells. Moreover, the epithelium damage in the 3D tissue model was significantly more severe than in 2D transwells and damage correlated significantly with the level of toxin activity detected but not with the amount of germinated spores. Combined, these results show that the bioengineered 3D tissue model provides a powerful system with which to study early events leading to toxin production and tissue damage of C. difficile with mammalian cells under anaerobic conditions. Furthermore, these systems may be useful for examining the effects of microbiota, novel drugs and other potential therapeutics directed towards C. difficile infections. Copyright © 2018 Elsevier Ltd. All rights reserved.
Full Text Available Clostridium difficile is a diarrheagenic pathogen associated with significant mortality and morbidity. While its glucosylating toxins are primary virulence determinants, there is increasing appreciation of important roles for non-toxin factors in C. difficile pathogenesis. Cell wall glycopolymers (CWGs influence the virulence of various pathogens. Five C. difficile CWGs, including PSII, have been structurally characterized, but their biosynthesis and significance in C. difficile infection is unknown. We explored the contribution of a conserved CWG locus to C. difficile cell-surface integrity and virulence. Attempts at disrupting multiple genes in the locus, including one encoding a predicted CWG exporter mviN, were unsuccessful, suggesting essentiality of the respective gene products. However, antisense RNA-mediated mviN downregulation resulted in slight morphology defects, retarded growth, and decreased surface PSII deposition. Two other genes, lcpA and lcpB, with putative roles in CWG anchoring, could be disrupted by insertional inactivation. lcpA- and lcpB- mutants had distinct phenotypes, implying non-redundant roles for the respective proteins. The lcpB- mutant was defective in surface PSII deposition and shedding, and exhibited a remodeled cell surface characterized by elongated and helical morphology, aberrantly-localized cell septae, and an altered surface-anchored protein profile. Both lcpA- and lcpB- strains also displayed heightened virulence in a hamster model of C. difficile disease. We propose that gene products of the C. difficile CWG locus are essential, that they direct the production/assembly of key antigenic surface polysaccharides, and thereby have complex roles in virulence.
Hryckowian, Andrew J; Van Treuren, William; Smits, Samuel A; Davis, Nicole M; Gardner, Jackson O; Bouley, Donna M; Sonnenburg, Justin L
Clostridium difficile is an opportunistic diarrhoeal pathogen, and C. difficile infection (CDI) represents a major health care concern, causing an estimated 15,000 deaths per year in the United States alone 1 . Several enteric pathogens, including C. difficile, leverage inflammation and the accompanying microbial dysbiosis to thrive in the distal gut 2 . Although diet is among the most powerful available tools for affecting the health of humans and their relationship with their microbiota, investigation into the effects of diet on CDI has been limited. Here, we show in mice that the consumption of microbiota-accessible carbohydrates (MACs) found in dietary plant polysaccharides has a significant effect on CDI. Specifically, using a model of antibiotic-induced CDI that typically resolves within 12 days of infection, we demonstrate that MAC-deficient diets perpetuate CDI. We show that C. difficile burdens are suppressed through the addition of either a diet containing a complex mixture of MACs or a simplified diet containing inulin as the sole MAC source. We show that switches between these dietary conditions are coincident with changes to microbiota membership, its metabolic output and C. difficile-mediated inflammation. Together, our data demonstrate the outgrowth of MAC-utilizing taxa and the associated end products of MAC metabolism, namely, the short-chain fatty acids acetate, propionate and butyrate, are associated with decreased C. difficile fitness despite increased C. difficile toxin expression in the gut. Our findings, when placed into the context of the known fibre deficiencies of a human Western diet, provide rationale for pursuing MAC-centric dietary strategies as an alternate line of investigation for mitigating CDI.
Community-onset Clostridium difficile-associated diarrhoea not associated with antibiotic usage--two case reports with review of the changing epidemiology of Clostridium difficile-associated diarrhoea
Bauer, M. P.; Goorhuis, A.; Koster, T.; Numan-Ruberg, S. C.; Hagen, E. C.; Debast, S. B.; Kuijper, E. J.; van Dissel, J. T.
The emergence of hypervirulent strains of Clostridium difficile causing outbreaks in hospitals and nursing homes may result in a greater than before spread of the bacterium in the community. By consequence, the incidence of community-onset cases of Clostridium difficile-associated diarrhoea (CDAD)
Anosova, Natalie G; Brown, Anna M; Li, Lu; Liu, Nana; Cole, Leah E; Zhang, Jinrong; Mehta, Hersh; Kleanthous, Harry
Clostridium difficile infection (CDI) has been identified as the leading cause of nosocomial diarrhoea and pseudomembranous colitis associated with antibiotic therapy. Recent epidemiological changes as well as increases in the number of outbreaks of strains associated with increased virulence and higher mortality rates underscore the importance of identifying alternatives to antibiotics to manage this important disease. Animal studies have clearly demonstrated the roles that toxins A and B play in gut inflammation as well as diarrhoea; therefore it is not surprising that serum anti-toxin A and B IgG are associated with protection against recurrent CDI. In humans, strong humoral toxin-specific immune responses elicited by natural C. difficile infection is associated with recovery and lack of disease recurrence, whereas insufficient humoral responses are associated with recurrent CDI. The first generation of C. difficile vaccine that contained inactivated toxin A and B was found to be completely protective against death and diarrhoea in the hamster C. difficile challenge model. When tested in young healthy volunteers in Phase I clinical trials, this investigational vaccine was shown to be safe and immunogenic. Moreover, in a separate study this vaccine was able to prevent further relapses in three out of three patients who had previously suffered from chronic relapsing C. difficile-associated diarrhoea. Herein we examined the immunogenicity and protective activity of a next-generation Sanofi Pasteur two-component highly purified toxoid vaccine in a C. difficile hamster model. This model is widely recognized as a stringent and relevant choice for the evaluation of novel treatment strategies against C. difficile and was used in preclinical testing of the first-generation vaccine candidate. Intramuscular (i.m.) immunizations with increasing doses of this adjuvanted toxoid vaccine protected hamsters from mortality and disease symptoms in a dose-dependent manner. ELISA
Full Text Available Objective: The most common etiology of infectious diarrhea in hospitalized patients is Clostridium difficile. No single laboratory test yields a definitive diagnosis. Four methods were evaluated for their sensitivity and specificity in patients who had clinically defined C difficile-associated diarrhea.
Alfa, Michelle J.; Kabani, Amin; Lyerly, David; Moncrief, Scott; Neville, Laurie M.; Al-Barrak, Ali; Harding, Godfrey K. H.; Dyck, Brenda; Olekson, Karen; Embil, John M.
Clostridium difficile-associated diarrhea (CAD) is a very common nosocomial infection that contributes significantly to patient morbidity and mortality as well as to the cost of hospitalization. Previously, strains of toxin A-negative, toxin B-positive C. difficile were not thought to be associated with clinically significant disease. This study reports the characterization of a toxin A-negative, toxin B-positive strain of C. difficile that was responsible for a recently described nosocomial outbreak of CAD. Analysis of the seven patient isolates from the outbreak by pulsed-field gel electrophoresis indicated that this outbreak was due to transmission of a single strain of C. difficile. Our characterization of this strain (HSC98) has demonstrated that the toxin A gene lacks 1.8 kb from the carboxy repetitive oligopeptide (CROP) region but apparently has no other major deletions from other regions of the toxin A or toxin B gene. The remaining 1.3-kb fragment of the toxin A CROP region from strain HSC98 showed 98% sequence homology with strain 1470, previously reported by M. Weidmann in 1997 (GenBank accession number Y12616), suggesting that HSC98 is toxinotype VIII. The HSC98 strain infecting patients involved in this outbreak produced the full spectrum of clinical illness usually associated with C. difficile-associated disease. This pathogenic spectrum was manifest despite the inability of this strain to alter tight junctions as determined by using in vitro tissue culture testing, which suggested that no functional toxin A was produced by this strain. PMID:10878068
Bibbò, Stefano; Lopetuso, Loris Riccardo; Ianiro, Gianluca; Di Rienzo, Teresa; Gasbarrini, Antonio; Cammarota, Giovanni
Recurrent Clostridium difficile infection represents a burdensome clinical issue whose epidemiology is increasing worldwide. The pathogenesis is not yet completely known. Recent observations suggest that the alteration of the intestinal microbiota and impaired innate immunity may play a leading role in the development of recurrent infection. Various factors can cause dysbiosis. The causes most involved in the process are antibiotics, NSAIDs, acid suppressing therapies, and age. Gut microbiota impairment can favor Clostridium difficile infection through several mechanisms, such as the alteration of fermentative metabolism (especially SCFAs), the alteration of bile acid metabolism, and the imbalance of antimicrobial substances production. These factors alter the intestinal homeostasis promoting the development of an ecological niche for Clostridium difficile and of the modulation of immune response. Moreover, the intestinal dysbiosis can promote a proinflammatory environment, whereas Clostridium difficile itself modulates the innate immunity through both toxin-dependent and toxin-independent mechanisms. In this narrative review, we discuss how the intestinal microbiota modifications and the modulation of innate immune response can lead to and exacerbate Clostridium difficile infection.
Buffie, Charlie G.; Bucci, Vanni; Stein, Richard R.; McKenney, Peter T.; Ling, Lilan; Gobourne, Asia; No, Daniel; Liu, Hui; Kinnebrew, Melissa; Viale, Agnes; Littmann, Eric; van den Brink, Marcel R. M.; Jenq, Robert R.; Taur, Ying; Sander, Chris; Cross, Justin R.; Toussaint, Nora C.; Xavier, Joao B.; Pamer, Eric G.
The gastrointestinal tracts of mammals are colonized by hundreds of microbial species that contribute to health, including colonization resistance against intestinal pathogens. Many antibiotics destroy intestinal microbial communities and increase susceptibility to intestinal pathogens. Among these, Clostridium difficile, a major cause of antibiotic-induced diarrhoea, greatly increases morbidity and mortality in hospitalized patients. Which intestinal bacteria provide resistance to C. difficile infection and their in vivo inhibitory mechanisms remain unclear. Here we correlate loss of specific bacterial taxa with development of infection, by treating mice with different antibiotics that result in distinct microbiota changes and lead to varied susceptibility to C. difficile. Mathematical modelling augmented by analyses of the microbiota of hospitalized patients identifies resistance-associated bacteria common to mice and humans. Using these platforms, we determine that Clostridium scindens, a bile acid 7α-dehydroxylating intestinal bacterium, is associated with resistance to C. difficile infection and, upon administration, enhances resistance to infection in a secondary bile acid dependent fashion. Using a workflow involving mouse models, clinical studies, metagenomic analyses, and mathematical modelling, we identify a probiotic candidate that corrects a clinically relevant microbiome deficiency. These findings have implications for the rational design of targeted antimicrobials as well as microbiome-based diagnostics and therapeutics for individuals at risk of C. difficile infection.
Full Text Available Greg Hussack,1 Jamshid Tanha1–3 1Human Health Therapeutics Portfolio, National Research Council Canada, Ottawa, 2School of Environmental Sciences, University of Guelph, Guelph, 3Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada Abstract: Clostridium difficile continues to be one of the most prevalent hospital-acquired bacterial infections in the developed world, despite the recent introduction of a novel and effective antibiotic agent (fidaxomicin. Alternative approaches under investigation to combat the anaerobic Gram-positive bacteria include fecal transplantation therapy, vaccines, and antibody-based immunotherapies. In this review, we catalog the recent advances in antibody-based approaches under development and in the clinic for the treatment of C. difficile infection. By and large, inhibitory antibodies that recognize the primary C. difficile virulence factors, toxin A and toxin B, are the most popular passive immunotherapies under investigation. We provide a detailed summary of the toxin epitopes recognized by various antitoxin antibodies and discuss general trends on toxin inhibition efficacy. In addition, antibodies to other C. difficile targets, such as surface-layer proteins, binary toxin, motility factors, and adherence and colonization factors, are introduced in this review. Keywords: antibody, Clostridium difficile, immunotherapy, toxin
Thabit, Abrar K; Nicolau, David P
Decision to test for Clostridium difficile infection (CDI) is usually made when patients have loose stools with Bristol stool score of ≥5. We aimed to assess the relationship between bacterial load of C. difficile and Bristol stool scale, as well as stool frequency in stool samples collected from patients infected with the organism. Samples were collected at baseline, during therapy, and at the end of therapy. Spearman correlation test was used to evaluate these relationships. No correlation between Bristol stool scale and fecal load of C. difficile was found for both spores and vegetative cells at all time points as counts were persistently high (P = non-significant). Weak positive correlations were found between stool frequency and fecal load of C. difficile spores and vegetative cells (r s = 0.22 and 0.24, P = 0.04 and 0.03, respectively). These findings indicate that quantitative colony counts were sufficiently high to detect C. difficile, irrespective of stool consistency, and suggest that semiformed stool should be sought for the pathogen in symptomatic patients with frequent stools.
Full Text Available Recurrent Clostridium difficile infection represents a burdensome clinical issue whose epidemiology is increasing worldwide. The pathogenesis is not yet completely known. Recent observations suggest that the alteration of the intestinal microbiota and impaired innate immunity may play a leading role in the development of recurrent infection. Various factors can cause dysbiosis. The causes most involved in the process are antibiotics, NSAIDs, acid suppressing therapies, and age. Gut microbiota impairment can favor Clostridium difficile infection through several mechanisms, such as the alteration of fermentative metabolism (especially SCFAs, the alteration of bile acid metabolism, and the imbalance of antimicrobial substances production. These factors alter the intestinal homeostasis promoting the development of an ecological niche for Clostridium difficile and of the modulation of immune response. Moreover, the intestinal dysbiosis can promote a proinflammatory environment, whereas Clostridium difficile itself modulates the innate immunity through both toxin-dependent and toxin-independent mechanisms. In this narrative review, we discuss how the intestinal microbiota modifications and the modulation of innate immune response can lead to and exacerbate Clostridium difficile infection.
LaMarche, Matthew J.; Leeds, Jennifer A.; Amaral, Adam; Brewer, Jason T.; Bushell, Simon M.; Deng, Gejing; Dewhurst, Janetta M.; Ding, Jian; Dzink-Fox, JoAnne; Gamber, Gabriel; Jain, Akash; Lee, Kwangho; Lee, Lac; Lister, Troy; McKenney, David; Mullin, Steve; Osborne, Colin; Palestrant, Deborah; Patane, Michael A.; Rann, Elin M.; Sachdeva, Meena; Shao, Jian; Tiamfook, Stacey; Trzasko, Anna; Whitehead, Lewis; Yifru, Aregahegn; Yu, Donghui; Yan, Wanlin; Zhu, Qingming (Novartis)
Clostridium difficile (C. difficile) is a Gram positive, anaerobic bacterium that infects the lumen of the large intestine and produces toxins. This results in a range of syndromes from mild diarrhea to severe toxic megacolon and death. Alarmingly, the prevalence and severity of C. difficile infection are increasing; thus, associated morbidity and mortality rates are rising. 4-Aminothiazolyl analogues of the antibiotic natural product GE2270 A (1) were designed, synthesized, and optimized for the treatment of C. difficile infection. The medicinal chemistry effort focused on enhancing aqueous solubility relative to that of the natural product and previous development candidates (2, 3) and improving antibacterial activity. Structure-activity relationships, cocrystallographic interactions, pharmacokinetics, and efficacy in animal models of infection were characterized. These studies identified a series of dicarboxylic acid derivatives, which enhanced solubility/efficacy profile by several orders of magnitude compared to previously studied compounds and led to the selection of LFF571 (4) as an investigational new drug for treating C. difficile infection.
Background An ancillary finding in previous research has suggested that the use of antidepressant medications increases the risk of developing Clostridium difficile infection (CDI). Our objective was to evaluate whether depression or the use of anti-depressants altered the risk of developing CDI, using two distinct datasets and study designs. Methods In Study 1, we conducted a longitudinal investigation of a nationally representative sample of older Americans (n = 16,781), linking data from biennial interviews to physician and emergency department visits, stays in hospital and skilled nursing facilities, home health visits, and other outpatient visits. In Study 2, we completed a clinical investigation of hospitalized adults who were tested for C. difficile (n = 4047), with cases testing positive and controls testing negative. Antidepressant medication use prior to testing was ascertained. Results The population-based rate of CDI in older Americans was 282.9/100,000 person-years (95% confidence interval (CI)) 226.3 to 339.5) for individuals with depression and 197.1/100,000 person-years for those without depression (95% CI 168.0 to 226.1). The odds of CDI were 36% greater in persons with major depression (95% CI 1.06 to 1.74), 35% greater in individuals with depressive disorders (95% CI 1.05 to 1.73), 54% greater in those who were widowed (95% CI 1.21 to 1.95), and 25% lower in adults who did not live alone (95% CI 0.62 to 0.92). Self-reports of feeling sad or having emotional, nervous or psychiatric problems at baseline were also associated with the later development of CDI. Use of certain antidepressant medications during hospitalization was associated with altered risk of CDI. Conclusions Adults with depression and who take specific anti-depressants seem to be more likely to develop CDI. Older adults who are widowed or who live alone are also at greater risk of CDI. PMID:23647647
Viljoen, G.J.; Crowther, J.R.; Nel, L.H.
The uses of nucleic acid-directed methods have increased significantly in the past five years and have made important contributions to disease control country programmes for improving national and international trade. These developments include the more routine use of PCR as a diagnostic tool in veterinary diagnostic laboratories. However, there are many problems associated with the transfer and particularly, the application of this technology. These include lack of consideration of: the establishment of quality-assured procedures, the required set-up of the laboratory and the proper training of staff. This can lead to a situation where results are not assured. This book gives a comprehensive account of the practical aspects of PCR and strong consideration is given to ensure its optimal use in a laboratory environment. This includes the setting-up of a PCR laboratory; Good Laboratory Practice and standardised PCR protocols to detect animal disease pathogens. Examples of Standard Operating Procedures as used in individual specialist laboratories and an outline of training materials necessary for PCR technology transfer are presented. The difficulties, advantages and disadvantages in PCR applications are explained and placed in context with other test systems. Emphasis is placed on the use of PCR for detection of pathogens, with a particular focus on diagnosticians and scientists from the developing world. It is hoped that this book will enable readers from various disciplines and levels of expertise to better judge the merits of PCR and to increase their skills and knowledge in order to assist in a more logical, efficient and assured use of this technology
The Role of Glutamate Dehydrogenase (GDH Testing Assay in the Diagnosis of Clostridium difficile Infections: A High Sensitive Screening Test and an Essential Step in the Proposed Laboratory Diagnosis Workflow for Developing Countries like China.
Full Text Available The incidence and severity of Clostridium difficile infection (CDI in North America and Europe has increased significantly since the 2000s. However, CDI is not widely recognized in China and other developing countries due to limited laboratory diagnostic capacity and low awareness. Most published studies on laboratory workflows for CDI diagnosis are from developed countries, and thus may not be suitable for most developing countries. Therefore, an alternative strategy for developing countries is needed. In this study, we evaluated the performance of the Glutamate Dehydrogenase (GDH test and its associated workflow on 416 fecal specimens from suspected CDI cases. The assay exhibited excellent sensitivity (100.0% and specificity (92.8%, compared to culture based method, and thus could be a good screening marker for C. difficile but not for indication of toxin production. The VIDAS CDAB assay, which can detect toxin A/B directly from fecal specimens, showed good specificity (99.7% and positive predictive value (97.2%, but low sensitivity (45.0% and negative predictive value (88.3%, compared with PCR-based toxin gene detection. Therefore, we propose a practical and efficient GDH test based workflow strategy for the laboratory diagnosis of CDI in developing countries like China. By applying this new workflow, the CDI laboratory diagnosis rate was notably improved in our center, yet the increasing cost was kept at a minimum level. Furthermore, to gain some insights into the genetic population structure of C. difficile isolates from our hospital, we performed MLST and PCR toxin gene typing.
The Role of Glutamate Dehydrogenase (GDH) Testing Assay in the Diagnosis of Clostridium difficile Infections: A High Sensitive Screening Test and an Essential Step in the Proposed Laboratory Diagnosis Workflow for Developing Countries like China.
Cheng, Jing-Wei; Xiao, Meng; Kudinha, Timothy; Xu, Zhi-Peng; Sun, Lin-Ying; Hou, Xin; Zhang, Li; Fan, Xin; Kong, Fanrong; Xu, Ying-Chun
The incidence and severity of Clostridium difficile infection (CDI) in North America and Europe has increased significantly since the 2000s. However, CDI is not widely recognized in China and other developing countries due to limited laboratory diagnostic capacity and low awareness. Most published studies on laboratory workflows for CDI diagnosis are from developed countries, and thus may not be suitable for most developing countries. Therefore, an alternative strategy for developing countries is needed. In this study, we evaluated the performance of the Glutamate Dehydrogenase (GDH) test and its associated workflow on 416 fecal specimens from suspected CDI cases. The assay exhibited excellent sensitivity (100.0%) and specificity (92.8%), compared to culture based method, and thus could be a good screening marker for C. difficile but not for indication of toxin production. The VIDAS CDAB assay, which can detect toxin A/B directly from fecal specimens, showed good specificity (99.7%) and positive predictive value (97.2%), but low sensitivity (45.0%) and negative predictive value (88.3%), compared with PCR-based toxin gene detection. Therefore, we propose a practical and efficient GDH test based workflow strategy for the laboratory diagnosis of CDI in developing countries like China. By applying this new workflow, the CDI laboratory diagnosis rate was notably improved in our center, yet the increasing cost was kept at a minimum level. Furthermore, to gain some insights into the genetic population structure of C. difficile isolates from our hospital, we performed MLST and PCR toxin gene typing.
Full Text Available Clostridium difficile (CD is the most common cause of nosocomial diarrhea in adults with high rates of morbidity and mortality. The epidemiology of CD infection (CDI has changed in the last few decades associated with increasing severity of the infection rate related to the occurrence of NAP1 hypervirulent strain and the emergence of the disease among ambulatory patients and the wider community. Although little is known about CDI in pediatric patients, CD is surprisingly recognized as an important pathogen in children. In this review article, we direct attention to the recent findings on the incidence and epidemiology of pediatric CDI, including the risk factors for infection, with special emphasis on the importance of CDI in infants and a population of children suffering from chronic gastrointestinal diseases or cancer. Despite recent pharmacotherapeutic protocols successfully used in children with CDI, we would like to draw attention to precautionary and preventive measures in terms of both unnecessary testing and uncritical use of antibiotics as the most important risk factors.
Full Text Available Clostridium difficile infection (CDI is a major cause of morbidity and biomarkers that predict severity of illness are needed. Procalcitonin (PCT, a serum biomarker with specificity for bacterial infections, has been little studied in CDI. We hypothesized that PCT associated with CDI severity.Serum PCT levels were measured for 69 cases of CDI. Chart review was performed to evaluate the presence of severity markers and concurrent acute bacterial infection (CABI. We defined the binary variables clinical score as having fever (T >38°C, acute organ dysfunction (AOD, and/or WBC >15,000 cells/mm(3 and expanded score, which included the clinical score plus the following: ICU admission, no response to therapy, colectomy, and/or death.In univariate analysis log10 PCT associated with clinical score (OR 3.13, 95% CI 1.69-5.81, P0.2 ng/mL was 81% sensitive/73% specific for a positive clinical score and had a negative predictive value of 90%.An elevated PCT level associated with the presence of CDI severity markers and CDI was unlikely to be severe with a serum PCT level below 0.2 ng/mL. The extent to which PCT changes during CDI therapy or predicts recurrent CDI remains to be quantified.
Salnikova, Maya S; Joshi, Sangeeta B; Rytting, J Howard; Warny, Michel; Middaugh, C Russell
To enhance the physical stability of Clostridium difficile toxoids A and B, screening for stabilizing compounds was performed. The screening of 30 GRAS compounds at various concentrations and in several combinations was performed in two parts. First, a high-throughput aggregation assay was used to screen for compounds which delayed or prevented aggregation of toxoids under stress conditions (toxoids at pH 5-5.5 were incubated at 55 degrees C for 55 or 75 min). Compounds which stabilized both proteins were further studied for their ability to delay unfolding under conditions leading to a presumably native-like folded state (pH 6.5). The thermal stability of the toxoids on the surface of Alhydrogel was monitored with DSC and also showed significant improvement in the presence of certain excipients. This study has generated information concerning the free and adjuvant bound toxoids behavior under a range of conditions (temperature, solutes) that can be used to design pharmaceutical formulations of enhanced physical stability. (c) 2008 Wiley-Liss, Inc. and the American Pharmacists Association
Hussam, Dina; Drees, Marci; Myerson, Scott; Duffalo, Chad; Mosby, Danielle; Herdman, Christine; Depalma, Fedele; Mcgraw, Patty; Bacon, Alfred E
Abstract Background Fecal microbiota transplant (FMT) for relapsing Clostridium difficile infections (CDI) allows for rapid repopulation of the colonic microbiome and may prevent future relapses. FMT is considered safe, however subsequent impact on weight and metabolism are incompletely understood. Animal studies have shown that alterations in microbiota lead to changes in weight; this is also suggested in humans, based on limited anecdotal evidence. This study explores changes in weight associated with FMT. Methods We conducted a retrospective observational study of patients who underwent FMT at our 1100-bed community-based academic healthcare system. FMT protocol requires 2 documented CDI relapses and failed vancomycin taper. FMT methods include colonoscopy, EGD and oral capsules. Of note, donor stool (OpenBiome, Boston, Massachusetts) criteria include BMI 5% gain 11 (65) >10% gain 6 (35) >5% loss 6 (50) >10% loss 2 (17) Average % of body weight change (among those with changes) - Gain 7.7 Loss 5.5 Conclusion In this limited population, it appears FMT may predispose to weight gain, which may reflect improved health with CDI cure. However, effects of FMT on patient’s microbiomes must also be considered. As this intervention becomes more widely used we must be increasingly aware of possible metabolic side effects and ensure documentation of weight changes as part of FMT protocols. Disclosures All authors: No reported disclosures.
Rodrigo Otávio Silveira Silva
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.
Silva, Rodrigo Otávio Silveira; Dorella, Fernanda Alves; Figueiredo, Henrique Cesar Pereira; Costa, Érica Azevedo; Pelicia, Vanessa; Ribeiro, Bruna Letícia Devidé; Ribeiro, Marcio Garcia; Paes, Antonio Carlos; Megid, Jane; Lobato, Francisco Carlos Faria
The aim of this study was to investigate Clostridium difficile and Clostridium perfringens in 82 diarrheic dogs positive for canine parvovirus type 2 (CPV). Enterotoxigenic C. perfringens type A was isolated from three (3.6%) dogs. One (1.2%) strain was also positive for NetE- and NetF-encoding genes, which are commonly associated with diarrhea in dogs. Toxigenic C. difficile was isolated from one animal (1.2%), which was also positive for A/B toxins. The present study identified C. difficile and C. perfringens infection in CPV-positive dogs. Further studies are necessary to clarify if clostridial infections may predispose or potentiate CPV-infection in dogs or vice versa. Copyright © 2017 Elsevier Ltd. All rights reserved.
Biswas, J S; Patel, A; Otter, J A; Wade, P; Newsholme, W; van Kleef, E; Goldenberg, S D
Fidaxomicin is sporicidal and may be associated with a reduced time to resolution of diarrhoea when used to treat patients with Clostridium difficile infection (CDI). This study investigated whether fidaxomicin for treatment of all patients with CDI reduced C. difficile environmental contamination. Surfaces in the rooms of 66 hospitalized patients treated with metronidazole and/or vancomycin and 68 hospitalized patients treated with fidaxomicin were sampled. Patients treated with fidaxomicin were less likely to contaminate their environment (25/68, 36.8%) than patients treated with metronidazole and/or vancomycin (38/66 57.6%) (P = 0.02). Treatment with fidaxomicin was associated with reduced environmental contamination with C. difficile. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Stephenson, Brittany; Lanzas, Cristina; Lenhart, Suzanne; Day, Judy
The spore-forming, gram-negative bacteria Clostridium difficile can cause severe intestinal illness. A striking increase in the number of cases of C. difficile infection (CDI) among hospitals has highlighted the need to better understand how to prevent the spread of CDI. In our paper, we modify and update a compartmental model of nosocomial C. difficile transmission to include vaccination. We then apply optimal control theory to determine the time-varying optimal vaccination rate that minimizes a combination of disease prevalence and spread in the hospital population as well as cost, in terms of time and money, associated with vaccination. Various hospital scenarios are considered, such as times of increased antibiotic prescription rate and times of outbreak, to see how such scenarios modify the optimal vaccination rate. By comparing the values of the objective functional with constant vaccination rates to those with time-varying optimal vaccination rates, we illustrate the benefits of time-varying controls.
Kelly A Fimlaid
Full Text Available Clostridium difficile is a Gram-positive spore-forming pathogen and a leading cause of nosocomial diarrhea. C. difficile infections are transmitted when ingested spores germinate in the gastrointestinal tract and transform into vegetative cells. Germination begins when the germinant receptor CspC detects bile salts in the gut. CspC is a subtilisin-like serine pseudoprotease that activates the related CspB serine protease through an unknown mechanism. Activated CspB cleaves the pro-SleC zymogen, which allows the activated SleC cortex hydrolase to degrade the protective cortex layer. While these regulators are essential for C. difficile spores to outgrow and form toxin-secreting vegetative cells, the mechanisms controlling their function have only been partially characterized. In this study, we identify the lipoprotein GerS as a novel regulator of C. difficile spore germination using targeted mutagenesis. A gerS mutant has a severe germination defect and fails to degrade cortex even though it processes SleC at wildtype levels. Using complementation analyses, we demonstrate that GerS secretion, but not lipidation, is necessary for GerS to activate SleC. Importantly, loss of GerS attenuates the virulence of C. difficile in a hamster model of infection. Since GerS appears to be conserved exclusively in related Peptostreptococcaeace family members, our results contribute to a growing body of work indicating that C. difficile has evolved distinct mechanisms for controlling the exit from dormancy relative to B. subtilis and other spore-forming organisms.
Sachdeva, Meena; Leeds, Jennifer A
LFF571 is a novel semisynthetic thiopeptide antibacterial that is undergoing investigation for safety and efficacy in patients with moderate Clostridium difficile infections. LFF571 inhibits bacterial protein synthesis by interacting with elongation factor Tu (EF-Tu) and interrupting complex formation between EF-Tu and aminoacyl-tRNA. Given this mechanism of action, we hypothesized that concentrations of LFF571 below those necessary to inhibit bacterial growth would reduce steady-state toxin levels in C. difficile cultures. We investigated C. difficile growth and toxin A and B levels in the presence of LFF571, fidaxomicin, vancomycin, and metronidazole. LFF571 led to strain-dependent effects on toxin production, including decreased toxin levels after treatment with subinhibitory concentrations, and more rapid declines in toxin production than in inhibition of colony formation. Fidaxomicin, which is an RNA synthesis inhibitor, conferred a similar pattern to LFF571 with respect to toxin levels versus viable cell counts. The incubation of two toxigenic C. difficile strains with subinhibitory concentrations of vancomycin, a cell wall synthesis inhibitor, increased toxin levels in the supernatant over those of untreated cultures. A similar phenomenon was observed with one metronidazole-treated strain of C. difficile. These studies indicate that LFF571 and fidaxomicin generally result in decreased C. difficile toxin levels in culture supernatants, whereas treatment of some strains with vancomycin or metronidazole had the potential to increase toxin levels. Although the relevance of these findings remains to be studied in patients, reducing toxin levels with sub-growth-inhibitory concentrations of an antibiotic is hypothesized to be beneficial in alleviating symptoms. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Full Text Available Background: Few studies have evaluated the incidence and risk factors of Clostridium difficile infection (CDI in the adult Polish population, in particular in solid organ recipients hospitalized at the nephrological ward.Aim: The aim of this study was to analyze Clostridium difficile infections (CDI among patients hospitalized in the Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia in Katowice.Material/Methods: Thirty-seven patients with Clostridium difficile infection diagnosed between October 2011 and November 2013 (26 months, identified among a total of 3728 patients hospitalized in this department during this period, were included in this retrospective, single-center study. The CDI definition was based on the current recommendations of the European Society of Clinical Microbiology and Infectious Diseases.Results: The observation period was divided into two 13-month intervals. Increased incidence (of borderline significance of CDI in the second period compared to the first period was observed (1.33% vs 0.65% respectively; p=0.057. Patients after kidney (n=11, kidney and pancreas (n=2 and liver (n=5 transplantation represented 48% of the analyzed CDI patients, and in half of these patients (50% CDI symptoms occurred within the first 3 months after transplantation. Clostridium difficile infection leads to irreversible deterioration of graft function in 38% of kidney recipients. Most incidents of CDI (70% were identified as nosocomial infection.Conclusions: 1. Clostridium difficile infection is particularly common among patients in the early period after solid organ transplantation. 2. Clostridium difficile infection may lead to irreversible deterioration of transplanted kidney function.
Clostridium difficile is the etiological agent of antibiotic-associated diarrhoea (AAD) and pseudomembranous colitis in humans. The role of the surface layer proteins (SLPs) in this disease has not yet been fully explored. The aim of this study was to investigate a role for SLPs in the recognition of C. difficile and the subsequent activation of the immune system. Bone marrow derived dendritic cells (DCs) exposed to SLPs were assessed for production of inflammatory cytokines, expression of cell surface markers and their ability to generate T helper (Th) cell responses. DCs isolated from C3H\\/HeN and C3H\\/HeJ mice were used in order to examine whether SLPs are recognised by TLR4. The role of TLR4 in infection was examined in TLR4-deficient mice. SLPs induced maturation of DCs characterised by production of IL-12, TNFα and IL-10 and expression of MHC class II, CD40, CD80 and CD86. Furthermore, SLP-activated DCs generated Th cells producing IFNγ and IL-17. SLPs were unable to activate DCs isolated from TLR4-mutant C3H\\/HeJ mice and failed to induce a subsequent Th cell response. TLR4(-\\/-) and Myd88(-\\/-), but not TRIF(-\\/-) mice were more susceptible than wild-type mice to C. difficile infection. Furthermore, SLPs activated NFκB, but not IRF3, downstream of TLR4. Our results indicate that SLPs isolated from C. difficile can activate innate and adaptive immunity and that these effects are mediated by TLR4, with TLR4 having a functional role in experimental C. difficile infection. This suggests an important role for SLPs in the recognition of C. difficile by the immune system.
Leber, Andrew; Viladomiu, Monica; Hontecillas, Raquel; Abedi, Vida; Philipson, Casandra; Hoops, Stefan; Howard, Brad; Bassaganya-Riera, Josep
Clostridium difficile infections are associated with the use of broad-spectrum antibiotics and result in an exuberant inflammatory response, leading to nosocomial diarrhea, colitis and even death. To better understand the dynamics of mucosal immunity during C. difficile infection from initiation through expansion to resolution, we built a computational model of the mucosal immune response to the bacterium. The model was calibrated using data from a mouse model of C. difficile infection. The model demonstrates a crucial role of T helper 17 (Th17) effector responses in the colonic lamina propria and luminal commensal bacteria populations in the clearance of C. difficile and colonic pathology, whereas regulatory T (Treg) cells responses are associated with the recovery phase. In addition, the production of anti-microbial peptides by inflamed epithelial cells and activated neutrophils in response to C. difficile infection inhibit the re-growth of beneficial commensal bacterial species. Computational simulations suggest that the removal of neutrophil and epithelial cell derived anti-microbial inhibitions, separately and together, on commensal bacterial regrowth promote recovery and minimize colonic inflammatory pathology. Simulation results predict a decrease in colonic inflammatory markers, such as neutrophilic influx and Th17 cells in the colonic lamina propria, and length of infection with accelerated commensal bacteria re-growth through altered anti-microbial inhibition. Computational modeling provides novel insights on the therapeutic value of repopulating the colonic microbiome and inducing regulatory mucosal immune responses during C. difficile infection. Thus, modeling mucosal immunity-gut microbiota interactions has the potential to guide the development of targeted fecal transplantation therapies in the context of precision medicine interventions. PMID:26230099
Geeraerts, S; Ducatelle, R; Haesebrouck, F; Van Immerseel, F
Probiotics might offer an attractive alternative for standard antibiotic therapy to treat Clostridium difficile infections (CDI). We specifically selected a Bacillus amyloliquefaciens strain for its high in vitro antibacterial activity against C. difficile and tested its efficacy to prevent CDI in a mouse model. B. amyloliquefaciens supernatant was tested against a large collection of C. difficile strains using an agar well diffusion test. B. amyloliquefaciens was orally administered to C57BL/6 mice in which CDI was induced using C. difficile VPI 10463, and its effect was compared with control mice receiving no treatment and mice receiving Saccharomyces boulardii. Mice were followed up daily for signs of disease including weight loss. At necropsy, the colon was collected and subjected to histopathological analysis. C. difficile toxin A/B levels and colon weight/length and colon/body weight ratios were calculated. B. amyloliquefaciens supernatant was able to inhibit the growth of all C. difficile strains. Results of the in vivo trial indicated a significant weight loss for untreated and S. boulardii-treated mice as compared to B. amyloliquefaciens-treated mice. C. difficile toxin A and B levels were significantly higher for untreated and S. boulardii-treated mice than B. amyloliquefaciens-treated mice. A significantly lower degree of colon damage was detected for B. amyloliquefaciens-treated mice as compared to untreated and S. boulardii-treated mice, based on histopathological analysis, colon weight/length and colon/body weight ratios. Administration of B. amyloliquefaciens was successful in preventing CDI in a mouse model. © 2015 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.
Manthey, C F; Eckmann, L; Fuhrmann, V
Infections with Clostridium difficile (CDI) represent a major burden for the health care system. Treatment is generally by antibiotic therapy with metronidazole and vancomycin, but efficacy remains suboptimal. Areas covered: This review discusses established and emerging treatment options for CDI, and current therapeutic guidelines, taking into account disease severity and risk of relapse. Expert commentary: New therapeutic approaches, including antibodies and new classes of antibiotics, and new measures for preventing infection with vaccines are under development in phase II/III clinical trials. We performed a systematic literature review using the search terms 'Clostridium difficile' and 'treatment'.
Hove, H; Tvede, M; Mortensen, P B
BACKGROUND: It has been hypothesized that Clostridium difficile and decreased colonic production of short-chain fatty acids (SCFAs) cause the development of antibiotic-associated diarrhoea. We therefore wanted to investigate the effects of an intensive and uniform antibiotic therapy on faecal SCFAs...... concentrations. C. difficile, and extent of diarrhoea. METHODS: Fifteen liver-transplanted patients who received oral bowel flora suppression therapy (6.3 g cefuroxime, 0.6 g tobramycin, and 0.5 g nystatin three times daily) were studied for 12 days before and 12 days after discontinuation of therapy. RESULTS...
Rodriguez, C; Van Broeck, J; Taminiau, B; Delmée, M; Daube, G
Recognised as the leading cause of nosocomial antibiotic-associated diarrhoea, the incidence of Clostridium difficile infection (CDI) remains high despite efforts to improve prevention and reduce the spread of the bacterium in healthcare settings. In the last decade, many studies have focused on the epidemiology and rapid diagnosis of CDI. In addition, different typing methods have been developed for epidemiological studies. This review explores the history of C. difficile and the current scope of the infection. The variety of available laboratory tests for CDI diagnosis and strain typing methods are also examined. Copyright © 2016 Elsevier Ltd. All rights reserved.
He, Miao; Miyajima, Fabio; Roberts, Paul; Ellison, Louise; Pickard, Derek J.; Martin, Melissa J.; Connor, Thomas R.; Harris, Simon R.; Fairley, Derek; Bamford, Kathleen B.; D?Arc, Stephanie; Brazier, Jon; Brown, Derek; Coia, John E.; Douce, Gill
Epidemic C. difficile (027/BI/NAP1) has rapidly emerged in the past decade as the leading cause of antibiotic-associated diarrhea worldwide. However, the key events in evolutionary history leading to its emergence and the subsequent patterns of global spread remain unknown. Here, we define the global population structure of C. difficile 027/BI/NAP1 using whole-genome sequencing and phylogenetic analysis. We show that two distinct epidemic lineages, FQR1 and FQR2, not one as previously thought...
Clostridium difficile testing algorithms using glutamate dehydrogenase antigen and C. difficile toxin enzyme immunoassays with C. difficile nucleic acid amplification testing increase diagnostic yield in a tertiary pediatric population.
Ota, Kaede V; McGowan, Karin L
We evaluated the performance of the rapid C. diff Quik Chek Complete's glutamate dehydrogenase antigen (GDH) and toxin A/B (CDT) tests in two algorithmic approaches for a tertiary pediatric population: algorithm 1 entailed initial testing with GDH/CDT followed by loop-mediated isothermal amplification (LAMP), and algorithm 2 entailed GDH/CDT followed by cytotoxicity neutralization assay (CCNA) for adjudication of discrepant GDH-positive/CDT-negative results. A true positive (TP) was defined as positivity by CCNA or positivity by LAMP plus another test (GDH, CDT, or the Premier C. difficile toxin A and B enzyme immunoassay [P-EIA]). A total of 141 specimens from 141 patients yielded 27 TPs and 19% prevalence. Sensitivity, specificity, positive predictive value, and negative predictive value were 56%, 100%, 100%, and 90% for P-EIA and 81%, 100%, 100%, and 96% for both algorithm 1 and algorithm 2. In summary, GDH-based algorithms detected C. difficile infections with superior sensitivity compared to P-EIA. The algorithms allowed immediate reporting of half of all TPs, but LAMP or CCNA was required to confirm the presence or absence of toxigenic C. difficile in GDH-positive/CDT-negative specimens.
Full Text Available We tested the hypothesis that Crohn's disease (CD-related genetic polymorphisms involved in host innate immunity are associated with shifts in human ileum-associated microbial composition in a cross-sectional analysis of human ileal samples. Sanger sequencing of the bacterial 16S ribosomal RNA (rRNA gene and 454 sequencing of 16S rRNA gene hypervariable regions (V1-V3 and V3-V5, were conducted on macroscopically disease-unaffected ileal biopsies collected from 52 ileal CD, 58 ulcerative colitis and 60 control patients without inflammatory bowel diseases (IBD undergoing initial surgical resection. These subjects also were genotyped for the three major NOD2 risk alleles (Leu1007fs, R708W, G908R and the ATG16L1 risk allele (T300A. The samples were linked to clinical metadata, including body mass index, smoking status and Clostridia difficile infection. The sequences were classified into seven phyla/subphyla categories using the Naïve Bayesian Classifier of the Ribosome Database Project. Centered log ratio transformation of six predominant categories was included as the dependent variable in the permutation based MANCOVA for the overall composition with stepwise variable selection. Polymerase chain reaction (PCR assays were conducted to measure the relative frequencies of the Clostridium coccoides - Eubacterium rectales group and the Faecalibacterium prausnitzii spp. Empiric logit transformations of the relative frequencies of these two microbial groups were included in permutation-based ANCOVA. Regardless of sequencing method, IBD phenotype, Clostridia difficile and NOD2 genotype were selected as associated (FDR ≤ 0.05 with shifts in overall microbial composition. IBD phenotype and NOD2 genotype were also selected as associated with shifts in the relative frequency of the C. coccoides--E. rectales group. IBD phenotype, smoking and IBD medications were selected as associated with shifts in the relative frequency of F. prausnitzii spp. These
Li, Boyu; Ma, Huachong; Wang, Zhenjun; Liu, Lihong
Clostridium difficile infection (CDI) is a symptomatic infection due to the spore-forming bacterium, C. difficile. Asymptomatic C. difficile colonization is the stage in absence of symptoms, with a prevalence of 1.4% to 21% on hospital admission. Proton-pump inhibitors (PPIs) was implicated as a novel potential contributor to CDI. PPIs injection could make asymptomatic C. difficile colonization progress to C. difficile associated diarrhea (CDAD). A postoperative colon cancer patient, who had been taking omeprazole for 4 years after operation, got asymptomatic C. difficile colonization. When he developed clinical symptoms of digestive tract, tumor recurrence was first suspected and intravenous omeprazole was prescribed, which ultimately led to progression to symptomatic CDI. In this report, we tell the confusing differential diagnosis of cancer-associated diseases and CDAD, and discuss the possibility of solving the PPIs overuse problem by making clinical pathway of PPIs use in Chinese hospitals. CDAD, incomplete intestinal obstruction, postoperation of colon cancer. Electrolyte replacement and rehydration. Parenteral nutrition support. Omeprazole was prescribed but withdrawn later, and oral vancomycin was given at a dose of 0.25 g 4 times per day for 10 days. Diarrhea was resolved, so long as the acid reflux and vomiting. We have 2 lessons here: Be aware of PPIs induced CDI, especially the asymptomatic C. difficile colonization. Making clinical pathway specified on PPIs use by pharmacists could be a practical way to solve the problem of PPIs overuse.
Full Text Available La comprensione del manuale di storia da parte dello studente straniero che apprende l’italiano come lingua di scolarizzazione è il problema che viene affrontato in questo articolo. Nella prima parte, introduttiva, dell’articolo si richiamano alcuni aspetti relativi all’apprendimento dell’italiano come lingua di scolarizzazione e alla comprensione dei testi per lo studio e si evidenziano in particolare, le caratteristiche linguistico-testuali dei manuali scolastici di storia e le aree di difficoltà che gli apprendenti possono incontrare. Nella seconda parte viene esaminato, facendo riferimento anche agli indici di difficoltà gulpease, un capitolo tratto da un manuale di scuola media di cui vengono messi in evidenza i tratti lessicali, morfo-sintattici, testuali e di contenuto che possono risultare di difficile comprensione per l’apprendente. L’articolo si conclude con una serie di proposte di semplificazione e/o di facilitazione del testo preso in esame che lo rendano accessibile allo studente e che possano essergli di aiuto nell’apprendere i contenuti disciplinari proposti. Reading for learning: The difficult case of history textbooks Understanding history textbooks for foreign students learning Italian at school is the problem addressed in this article. The first part discusses a few aspects of learning Italian at school and understanding texts and focuses on the textual-linguistic aspects of school history textbooks and the difficulties students may have with them. The second part investigates a chapter from a middle-school history textbook, highlighting the lexical, morpho-syntactic, textual and content traits that may cause learners difficulty in comprehension, referring to the GULPEASE difficulty index levels. The article concludes with a series of proposals for simplifying and/or facilitating the text examined in order to make it accessible to the student and offer help in learning the content.
Rao, Krishna; Walk, Seth T; Micic, Dejan; Chenoweth, Elizabeth; Deng, Lili; Galecki, Andrzej T; Jain, Ruchika; Trivedi, Itishree; Yu, Marie; Santhosh, Kavitha; Ring, Cathrin; Young, Vincent B; Huffnagle, Gary B; Aronoff, David M
Clostridium difficile infection (CDI) is a major cause of morbidity and biomarkers that predict severity of illness are needed. Procalcitonin (PCT), a serum biomarker with specificity for bacterial infections, has been little studied in CDI. We hypothesized that PCT associated with CDI severity. Serum PCT levels were measured for 69 cases of CDI. Chart review was performed to evaluate the presence of severity markers and concurrent acute bacterial infection (CABI). We defined the binary variables clinical score as having fever (T >38°C), acute organ dysfunction (AOD), and/or WBC >15,000 cells/mm(3) and expanded score, which included the clinical score plus the following: ICU admission, no response to therapy, colectomy, and/or death. In univariate analysis log10 PCT associated with clinical score (OR 3.13, 95% CI 1.69-5.81, PCABI, and extended care facility residence, log10 PCT associated with clinical score (OR 3.09, 95% CI 1.5-6.35, P = .002) and expanded score (OR 3.06, 95% CI 1.49-6.26, P = .002). PCT >0.2 ng/mL was 81% sensitive/73% specific for a positive clinical score and had a negative predictive value of 90%. An elevated PCT level associated with the presence of CDI severity markers and CDI was unlikely to be severe with a serum PCT level below 0.2 ng/mL. The extent to which PCT changes during CDI therapy or predicts recurrent CDI remains to be quantified.
Pérez-Topete, S E; Miranda-Aquino, T; Hernández-Portales, J A
Clostridium difficile (C. difficile) is a Gram-positive bacillus that is a common cause of diarrhea in the hospital environment, with a documented incidence of up to 10%. There are different methods to detect it, but a widely used test in our environment is the immunoassay for toxins A and B. The aim of our study was to 1) estimate the positive predictive value of the immunoassay for the detection of the C. difficile toxins A and B, 2) to establish the incidence of C. difficile-associated diarrhea in the hospital, and 3) to know the most common associated factors. A diagnostic test accuracy study was conducted within the time frame of January 2010 to August 2013 at the Hospital Christus Muguerza® Alta Especialidad on patients with symptoms suggestive of C. difficile-associated diarrhea that had a positive immunoassay test and confirmation of C. difficile through colon biopsy and stool culture. The immunoassay for toxins A and B was performed in 360 patients. Fifty-five of the cases had positive results, 35 of which showed the presence of C. difficile. Incidence was 10.2% and the positive predictive value of the test for C. difficile toxins A and B was 0.64 (95% CI, 0.51-0.76). Previous antibiotic therapy (n=29) and proton pump inhibitor use (n=19) were the most common associated factors. C. difficile incidence in our environment is similar to that found in the literature reviewed, but the positive predictive value of the test for toxin A and B detection was low. Copyright © 2016 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.
Conclusions: The expanded nutritional utilization profile of some newer C. difficile strains could be one of the reasons for infections in patients who are not exposed to the hospital environment or not undergoing antibiotic treatment. This nutritional profile could be used to design tube feeding formulas that reduce the risk of CDI.
Floods can contaminate potable water and other resources, thus increasing the potential for fecal-oral transmission of pathogens. Clostridium difficile is a bacterium that can spread by water and cause acute gastrointestinal illness. It often affects older adults who are hospital...
Planche, Timothy; Wilcox, Mark
Accurate diagnosis of Clostridium difficile infection (CDI) is essential for optimal treatment, prevention and control. There are two reference assays for CDI diagnosis: the cell cytotoxicity assay (CCTA) and toxigenic culture (TC). Importantly, these tests actually detect different targets: CCTA detects the presence of C difficile toxins (primarily toxin B, but also toxin A), whereas TC detects the presence in the stool of C difficile with the potential to produce toxin. Not surprisingly studies comparing the results of these assays show imperfect agreement. Thus, a faecal sample may be CCTA negative but TC positive, and this raises the crucial question about the clinical significance of the presence of C difficile with the capacity to produce toxin but no actual detectable free toxin. A positive TC result indicates that a patient with diarrhoea is potentially infectious. TC also has the advantage that the cultured isolate is available for typing and for susceptibility testing. In general, however, CCTA has been shown to be a better test for the laboratory confirmation of CDI, although additional culture may be needed to optimise sensitivity. Crucially, when these reference assays are used to determine the accuracy of alternative diagnostic tests, care should be taken to compare methods with their appropriate standard (ie, compare tests that target equivalent end-points). Such issues have contributed to the variable and often suboptimal performance of rapid diagnostic tests for CDI. Further research is urgently needed to improve knowledge of the utility of routine diagnostic tests in CDI and the factors that influence their performance.
Bakri, M.M.; Sutherland, A.D.; Brown, D.J.; Veselý, Pavel; Crossan, C.; Scobie, L.
Roč. 16, č. 6 (2009), s. 472-476 ISSN 0908-665X Grant - others:EC(XE) LSHB-CT-2006-037377 Institutional research plan: CEZ:AV0Z50520514 Keywords : C. difficile * hospital acquired infection * xenotransplant * zoonoses Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.711, year: 2009
Davies, A; Pottage, T; Bennett, A; Walker, J
The recent data for hospital-acquired infections suggest that infection rates for meticillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile are beginning to decrease. However, while there is still pressure to maintain this trend, the resistance of C. difficile spores to standard detergents continues to present a problem for many UK hospitals trying to prevent its spread or control outbreaks. Alternative disinfection technologies such as gaseous decontamination are currently being marketed to the healthcare sector as an alternative/supplement to manual disinfection, and have been shown to be effective in reducing environmental contamination. When used correctly, they offer a complementary technology to manual cleaning that increases the probability of an effective reduction in viability and provides a comparatively uniform distribution of disinfectant. Three gaseous decontamination technologies are examined for their suitability in reducing environmental contamination with C. difficile: gaseous hydrogen peroxide, chlorine dioxide and ozone. Air decontamination and UV-based technologies are also briefly described. We conclude that while there is a role to play for these new technologies in the decontamination of ward surfaces contaminated with C. difficile, the requirement for both a preclean before use and the limited 'in vivo' evidence means that extensive field trials are necessary to determine their cost-effectiveness in a healthcare setting. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.
Hensgens, Marjolein P. M.; Goorhuis, Abraham; Dekkers, Olaf M.; Kuijper, Ed J.
Clostridium difficile infections (CDIs) are common in developed countries and affect 250000 hospitalized patients annually in the USA. The most important risk factor for the disease is antibiotic therapy. To determine the period at risk for CDI after cessation of antibiotics, we performed a
Chaine, M.; Gubbels, S.; Voldstedlund, M.
The surveillance of Clostridium difficile (CD) in Denmark consists of laboratory based data from Departments of Clinical Microbiology (DCMs) sent to the National Registry of Enteric Pathogens (NREP). We validated a new surveillance system for CD based on the Danish Microbiology Database (MiBa). M...
Mahabir, Shanti; Lim, Ren Yik; Fitzpatrick, Fidelma; Magee, Colm; Keogan, Mary
The prevalence of Clostridium difficile infection (CDI) is increasing worldwide. Oral vancomycin is an effective and frequently used treatment. However, patients with CDI who are allergic to intravenous vancomycin cannot receive oral vancomycin due to the risk of anaphylaxis if given the oral form. We present a case where oral vancomycin desensitisation was used to successfully treat a vancomycin allergic patient with recurrent CDI.
Peterfreund, Gregory L; Vandivier, Lee E; Sinha, Rohini; Marozsan, Andre J; Olson, William C; Zhu, Jun; Bushman, Frederic D
Antibiotic disruption of the intestinal microbiota may cause susceptibility to pathogens that is resolved by progressive bacterial outgrowth and colonization. Succession is central to ecological theory but not widely documented in studies of the vertebrate microbiome. Here, we study succession in the hamster gut after treatment with antibiotics and exposure to Clostridium difficile. C. difficile infection is typically lethal in hamsters, but protection can be conferred with neutralizing antibodies against the A and B toxins. We compare treatment with neutralizing monoclonal antibodies (mAb) to treatment with vancomycin, which prolongs the lives of animals but ultimately fails to protect them from death. We carried out longitudinal deep sequencing analysis and found distinctive waves of succession associated with each form of treatment. Clindamycin sensitization prior to infection was associated with the temporary suppression of the previously dominant Bacteroidales and the fungus Saccinobaculus in favor of Proteobacteria. In mAb-treated animals, C. difficile proliferated before joining Proteobacteria in giving way to re-expanding Bacteroidales and the fungus Wickerhamomyces. However, the Bacteroidales lineages returning by day 7 were different from those that were present initially, and they persisted for the duration of the experiment. Animals treated with vancomycin showed a different set of late-stage lineages that were dominated by Proteobacteria as well as increased disparity between the tissue-associated and luminal cecal communities. The control animals showed no change in their gut microbiota. These data thus suggest different patterns of ecological succession following antibiotic treatment and C. difficile infection.
Gregory L Peterfreund
Full Text Available Antibiotic disruption of the intestinal microbiota may cause susceptibility to pathogens that is resolved by progressive bacterial outgrowth and colonization. Succession is central to ecological theory but not widely documented in studies of the vertebrate microbiome. Here, we study succession in the hamster gut after treatment with antibiotics and exposure to Clostridium difficile. C. difficile infection is typically lethal in hamsters, but protection can be conferred with neutralizing antibodies against the A and B toxins. We compare treatment with neutralizing monoclonal antibodies (mAb to treatment with vancomycin, which prolongs the lives of animals but ultimately fails to protect them from death. We carried out longitudinal deep sequencing analysis and found distinctive waves of succession associated with each form of treatment. Clindamycin sensitization prior to infection was associated with the temporary suppression of the previously dominant Bacteroidales and the fungus Saccinobaculus in favor of Proteobacteria. In mAb-treated animals, C. difficile proliferated before joining Proteobacteria in giving way to re-expanding Bacteroidales and the fungus Wickerhamomyces. However, the Bacteroidales lineages returning by day 7 were different from those that were present initially, and they persisted for the duration of the experiment. Animals treated with vancomycin showed a different set of late-stage lineages that were dominated by Proteobacteria as well as increased disparity between the tissue-associated and luminal cecal communities. The control animals showed no change in their gut microbiota. These data thus suggest different patterns of ecological succession following antibiotic treatment and C. difficile infection.
Deaths related to Clostridium difficile are on the rise in the United States. Matthew Redelings from the Los Angeles County Department of Health discusses the increase and what can be done to prevent this infection. Created: 1/8/2008 by Emerging Infectious Diseases. Date Released: 1/8/2008.
29 oct. 2015 ... Mise à jour | Villes sûres et inclusives Quelles sont les causes de la violence urbaine ? Un accès difficile aux services essentiels peut fomenter la concurrence et les conflits entre les groupes. Des solutions possibles ? Rendre accessibles aux communautés vulnérables l'eau potable, les services ...
Edmir Geraldo Fraga
Full Text Available Clostridium difficile is a leading cause of diarrhea in hospitalized patients worldwide. While metronidazole and vancomycin are the most prescribed antibiotics for the treatment of this infection, teicoplanin, tigecycline and nitazoxanide are alternatives drugs. Knowledge on the antibiotic susceptibility profiles is a basic step to differentiate recurrence from treatment failure due to antimicrobial resistance. Because C. difficile antimicrobial susceptibility is largely unknown in Brazil, we aimed to determine the profile of C. difficile strains cultivated from stool samples of inpatients with diarrhea and a positive toxin A/B test using both agar dilution and disk diffusion methods. All 50 strains tested were sensitive to metronidazole according to CLSI and EUCAST breakpoints with an MIC90 value of 2 μg/mL. Nitazoxanide and tigecycline were highly active in vitro against these strains with an MIC90 value of 0.125 μg/mL for both antimicrobials. The MIC90 were 4 μg/mL and 2 μg/mL for vancomycin and teicoplanin, respectively. A resistance rate of 8% was observed for moxifloxacin. Disk diffusion can be used as an alternative to screen for moxifloxacin resistance, nitazoxanide, tigecycline and metronidazole susceptibility, but it cannot be used for testing glycopeptides. Our results suggest that C. difficile strains from São Paulo city, Brazil, are susceptible to metronidazole and have low MIC90 values for most of the current therapeutic options available in Brazil.
Full Text Available The incidence of Clostridium difficile infections (CDI and Clostridium difficile-Associated Diarrhea (CDAD is increasing in Canada, USA, and Europe and represents a considerable clinical problem. Both naïve and hypervirulent strains can be considered as opportunistic bacteria affecting immunocompromised, antibiotic-treated, critical, or subcritical patients with a microbiota disruption. CDI arising is strictly related to antibiotic, single or combined, and/or proton pump inhibitor treatment. CDI can cause a syndrome with systemic involvement and complex treatment, sometimes requiring surgical interventions (e.g. colectomy in fulminant colitis. Antibiotic treatment with metronidazole by mouth is the first choice and generally vancomycin is administered in case of lack of effectiveness. Fidaxomicin is a new macrocyclic antibiotic for C. difficile with microflora-sparing properties. This paper reports our initial experience in 11 patients with non-responder or relapsing CDIs. Fidaxomicin was effective in 10 cases (91%. Only one patient with an active ulcerative colitis did not respond and was treated with fecal-microbiota transplantation. In two patients diarrhea persisted, but just the ulcerative colitis one was C. difficile-related. No adverse events were experienced.http://dx.doi.org/10.7175/cmi.v8i1s.956
Bradshaw, William J. [University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); Public Health England, Porton Down, Salisbury SP4 0JG (United Kingdom); Roberts, April K.; Shone, Clifford C. [Public Health England, Porton Down, Salisbury SP4 0JG (United Kingdom); Acharya, K. Ravi, E-mail: firstname.lastname@example.org [University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)
Two structures of Cwp84, a cysteine protease from the S-layer of C. difficile, are presented after propeptide cleavage. They reveal the movement of three loops, two in the active-site groove and one on the surface of the lectin-like domain, exposing a hydrophobic pocket. In recent decades, the global healthcare problems caused by Clostridium difficile have increased at an alarming rate. A greater understanding of this antibiotic-resistant bacterium, particularly with respect to how it interacts with the host, is required for the development of novel strategies for fighting C. difficile infections. The surface layer (S-layer) of C. difficile is likely to be of significant importance to host–pathogen interactions. The mature S-layer is formed by a proteinaceous array consisting of multiple copies of a high-molecular-weight and a low-molecular-weight S-layer protein. These components result from the cleavage of SlpA by Cwp84, a cysteine protease. The structure of a truncated Cwp84 active-site mutant has recently been reported and the key features have been identified, providing the first structural insights into the role of Cwp84 in the formation of the S-layer. Here, two structures of Cwp84 after propeptide cleavage are presented and the three conformational changes that are observed are discussed. These changes result in a reconfiguration of the active site and exposure of the hydrophobic pocket.
Aarestrup, Frank Møller; Tvede, Michael
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...
pulmonary disease, rheumatologic disease, peptic ulcer disease, mild liver disease, diabetes without chronic complications, diabetes with chronic...Clostridium difficile-associated diarrhea can be associated with stomach acid drugs known as proton pump inhibitors (PPIs). http://www.fda.gov/Drugs
Sanders, Nathan L; Bollinger, R Randal; Lee, Ryan; Thomas, Steven; Parker, William
Advances in understanding the interaction between the human immune system and the microbiome have led to an improved understanding of the function of the vermiform appendix as a safe-house for beneficial bacteria in the colon. These advances have been made despite long standing clinical observations that the appendectomy is a safe and effective procedure. However, more recent clinical data show that an appendectomy puts patients at increased risk for recurrent Clostridium difficile (C. difficile)-associated colitis, and probably other diseases associated with an altered microbiome. At the same time, appendectomy does not apparently put patients at risk for an initial onset of C. difficile-associated colitis. These clinical observations point toward the idea that the vermiform appendix might not effectively protect the microbiome in the face of broad spectrum antibiotics, the use of which precedes the initial onset of C. difficile-associated colitis. Further, these observations point to the idea that historically important threats to the microbiome such as infectious gastrointestinal pathogens have been supplanted by other threats, particularly the use of broad spectrum antibiotics. PMID:24039352
Full Text Available Virulent Clostridium difficile strains produce toxin A and/or toxin B that are the etiological agents of diarrhea and pseudomembranous colitis. Treatment of C. difficile infections (CDI has been hampered by resistance to multiple antibiotics, sporulation, emergence of strains with increased virulence, recurrence of the infection, and the lack of drugs that preserve or restore the colonic bacterial flora. As a result, there is new interest in non-antibiotic CDI treatments. The human conjugated bile salt taurocholate was previously shown in our laboratory to inhibit C. difficile toxin A and B activities in an in vitro assay. Here we demonstrate for the first time in an ex vivo assay that taurocholate can protect Caco-2 colonic epithelial cells from the damaging effects of the C. difficile toxins. Using caspase-3 and lactate dehydrogenase assays, we have demonstrated that taurocholate reduced the extent of toxin B-induced apoptosis and cell membrane damage. Confluent Caco-2 cells cultured with toxin B induced elevated caspase-3 activity. Remarkably, addition of 5 mM taurocholate reduced caspase-3 activity in cells treated with 2, 4, 6, and 12 µg/ml of toxin B by 99%, 78%, 64%, and 60%, respectively. Furthermore, spent culture medium from Caco-2 cells incubated with both toxin B and taurocholate exhibited significantly decreased lactate dehydrogenase activity compared to spent culture medium from cells incubated with toxin B only. Our results suggest that the mechanism of taurocholate-mediated inhibition functions at the level of toxin activity since taurocholate did not affect C. difficile growth and toxin production. These findings open up a new avenue for the development of non-antibiotic therapeutics for CDI treatment.
M. Lauren Donnelly
Full Text Available Clostridium difficile is a Gram-positive spore-forming obligate anaerobe that is a leading cause of antibiotic-associated diarrhea worldwide. In order for C. difficile to initiate infection, its aerotolerant spore form must germinate in the gut of mammalian hosts. While almost all spore-forming organisms use transmembrane germinant receptors to trigger germination, C. difficile uses the pseudoprotease CspC to sense bile salt germinants. CspC activates the related subtilisin-like protease CspB, which then proteolytically activates the cortex hydrolase SleC. Activated SleC degrades the protective spore cortex layer, a step that is essential for germination to proceed. Since CspC incorporation into spores also depends on CspA, a related pseudoprotease domain, Csp family proteins play a critical role in germination. However, how Csps are incorporated into spores remains unknown. In this study, we demonstrate that incorporation of the CspC, CspB, and CspA germination regulators into spores depends on CD0311 (renamed GerG, a previously uncharacterized hypothetical protein. The reduced levels of Csps in gerG spores correlate with reduced responsiveness to bile salt germinants and increased germination heterogeneity in single-spore germination assays. Interestingly, asparagine-rich repeat sequences in GerG’s central region facilitate spontaneous gel formation in vitro even though they are dispensable for GerG-mediated control of germination. Since GerG is found exclusively in C. difficile, our results suggest that exploiting GerG function could represent a promising avenue for developing C. difficile-specific anti-infective therapies.
Auchtung, Jennifer; Brown, Aaron; Boonma, Prapaporn; Oezguen, Numan; Ross, Caná L.; Luna, Ruth Ann; Runge, Jessica; Versalovic, James; Peniche, Alex; Dann, Sara M.; Britton, Robert A.; Haag, Anthony; Savidge, Tor C.
ABSTRACT Integration of antibiotic and probiotic therapy has the potential to lessen the public health burden of antimicrobial-associated diseases. Clostridium difficile infection (CDI) represents an important example where the rational design of next-generation probiotics is being actively pursued to prevent disease recurrence. Because intrinsic resistance to clinically relevant antibiotics used to treat CDI (vancomycin, metronidazole, and fidaxomicin) is a desired trait in such probiotic species, we screened several bacteria and identified Lactobacillus reuteri to be a promising candidate for adjunct therapy. Human-derived L. reuteri bacteria convert glycerol to the broad-spectrum antimicrobial compound reuterin. When supplemented with glycerol, strains carrying the pocR gene locus were potent reuterin producers, with L. reuteri 17938 inhibiting C. difficile growth at a level on par with the level of growth inhibition by vancomycin. Targeted pocR mutations and complementation studies identified reuterin to be the precursor-induced antimicrobial agent. Pathophysiological relevance was demonstrated when the codelivery of L. reuteri with glycerol was effective against C. difficile colonization in complex human fecal microbial communities, whereas treatment with either glycerol or L. reuteri alone was ineffective. A global unbiased microbiome and metabolomics analysis independently confirmed that glycerol precursor delivery with L. reuteri elicited changes in the composition and function of the human microbial community that preferentially targets C. difficile outgrowth and toxicity, a finding consistent with glycerol fermentation and reuterin production. Antimicrobial resistance has thus been successfully exploited in the natural design of human microbiome evasion of C. difficile, and this method may provide a prototypic precursor-directed probiotic approach. Antibiotic resistance and substrate bioavailability may therefore represent critical new determinants of
Spinler, Jennifer K; Auchtung, Jennifer; Brown, Aaron; Boonma, Prapaporn; Oezguen, Numan; Ross, Caná L; Luna, Ruth Ann; Runge, Jessica; Versalovic, James; Peniche, Alex; Dann, Sara M; Britton, Robert A; Haag, Anthony; Savidge, Tor C
Integration of antibiotic and probiotic therapy has the potential to lessen the public health burden of antimicrobial-associated diseases. Clostridium difficile infection (CDI) represents an important example where the rational design of next-generation probiotics is being actively pursued to prevent disease recurrence. Because intrinsic resistance to clinically relevant antibiotics used to treat CDI (vancomycin, metronidazole, and fidaxomicin) is a desired trait in such probiotic species, we screened several bacteria and identified Lactobacillus reuteri to be a promising candidate for adjunct therapy. Human-derived L. reuteri bacteria convert glycerol to the broad-spectrum antimicrobial compound reuterin. When supplemented with glycerol, strains carrying the pocR gene locus were potent reuterin producers, with L. reuteri 17938 inhibiting C. difficile growth at a level on par with the level of growth inhibition by vancomycin. Targeted pocR mutations and complementation studies identified reuterin to be the precursor-induced antimicrobial agent. Pathophysiological relevance was demonstrated when the codelivery of L. reuteri with glycerol was effective against C. difficile colonization in complex human fecal microbial communities, whereas treatment with either glycerol or L. reuteri alone was ineffective. A global unbiased microbiome and metabolomics analysis independently confirmed that glycerol precursor delivery with L. reuteri elicited changes in the composition and function of the human microbial community that preferentially targets C. difficile outgrowth and toxicity, a finding consistent with glycerol fermentation and reuterin production. Antimicrobial resistance has thus been successfully exploited in the natural design of human microbiome evasion of C. difficile , and this method may provide a prototypic precursor-directed probiotic approach. Antibiotic resistance and substrate bioavailability may therefore represent critical new determinants of probiotic
Swapan K Nath
Full Text Available A case-control study was undertaken to identify and quantify antimicrobial and nonantimicrobial drug risk factors associated with a sustained outbreak of Clostridium difficile diarrhea on two medical (teaching and nonteaching units and an oncology unit. In total, 80 cases associated with an endemic clone of toxigenic C difficile were compared with controls. Eighty controls were selected from a group of 290 controls randomly chosen from the outbreak period. The controls were matched to cases according to age, admitting diagnosis and unit of admission. Seventy (88% patients in the case group received at least one antibiotic before diarrhea, compared with 37 (46% patients in the control group. Major risk factors implicated in the development of C difficile diarrhea in hospitalized patients were the following antimicrobial agents: ceftazidime (adjusted odds ratio [aor]=26.01, 95% ci 5.67 to 119.19, P=0.0001; cefuroxime (aor=5.17, ci 1.86 to 14.36, P=0.005; ciprofloxacin (aor=3.81, ci 1.05 to 13.79, P=0.04; and clindamycin (aor=15.16, ci 2.93 to 78.44, P=0.004. This is the first time that the use of ciprofloxacin has been linked to the development of C difficile diarrhea. Use of gastrointestinal drugs (ranitidine, famotidine, cimetidine, omeprazole and sucralfate was also an added risk (aor=3.20, ci 1.39 to 7.34, P=0.01; however, antineoplastic therapy was not significant (P<0.53. Recognition of the specific high risk drugs may spur more restricted use of these agents, which may help in controlling C difficile diarrhea in hospitalized patients.
Since the introduction in the mid-1980s of analyses of minisatellites for DNA analyses, a revolution has taken place in forensic genetics. The subsequent invention of the PCR made it possible to develop forensic genetics tools that allow both very informative routine investigations and still more...... and more advanced, special investigations in cases concerning crime, paternity, relationship, disaster victim identification etc. The present review gives an update on the use of DNA investigations in forensic genetics....
-cycling steps to visualize amplicons, decelerating PCR sample processing and result calling. “One-stop PCR” was developed by including both the loading buffer and nontoxic staining dye within a single PCR tube, allowing direct loading and ...
Schoster, A.; Kokotovic, Branko; Permin, A.
Probiotics have gained importance in human and veterinary medicine to prevent enteric disease. Little information is available on commercial probiotic strains regarding their growth characteristics and inhibition of equine enteric pathogens such as Clostridium difficile and Clostridium perfringens...
Schoster, Angelika; Kokotovic, Branko; Permin, Anders
Probiotics have gained importance in human and veterinary medicine to prevent enteric disease. Little information is available on commercial probiotic strains regarding their growth characteristics and inhibition of equine enteric pathogens such as Clostridium difficile and Clostridium perfringens...... aerobic conditions was assessed. To evaluate inhibition of C. difficile and C. perfringens sterile supernatant of the probiotic culture was added to BHI inoculated with a standard C. difficile or C. perfringens suspension. Growth was measured spectrophotometrically at 0 and 24h and compared to the control...... (C. difficile or C. perfringens suspension in BHI). At pH 4 12% of strains showed >50% growth and 24% were unable to grow, however did survive. At pH 2 none of the tested strains grew or survived. Eighty eight percent showed >75% growth in 0.15% bile, 60% showed >75% growth in 0.3% bile. Ninety...
Dec 21, 2011 ... improved PCR method with speedy operation and ... novel PCR method is desired to compatibilize Taq DNA .... as template. A 20 ul traditional PCR mixture included 10×PCR reaction buffer, 2 µl, 40 mM dNTP (10mM each), 0.5 µl; Taq DNA polymerase, 0.2 µl (1 unit), 0.5 µl forward and reverse primer mix ...
Datta, Sibnarayan; Budhauliya, Raghvendra; Chatterjee, Soumya; Vanlalhmuaka; Veer, Vijay; Chakravarty, Runu
Polymerase chain reaction (PCR) is widely used in biological research and diagnostics because of its high sensitivity and specificity. However, the sensitivity of PCR is strongly influenced by topological characteristics of the template. Supercoiled templates are known to inhibit PCR, whereas linearized forms of the same supercoiled templates facilitate PCR. This study was conducted to compare the PCR efficiency of circular supercoiled DNA templates to their restriction endonuclease (RE)-mediated linearized forms. Additionally, we also evaluated the possibility of RE digestion of the circular supercoiled templates within the complete PCR buffer. Following a systematic approach, we demonstrated that circular supercoiled templates could be efficiently linearized by RE in the complete PCR buffer itself. This allowed linearization of circular supercoiled templates and their subsequent amplification in the PCR buffer in a single-tube format. Using this extremely simple RE-PCR approach, we documented up to tenfold increases in detection efficiency of PCR with two different circular supercoiled templates of clinical origin, including an international calibration standard. This inexpensive and easy approach to increasing PCR sensitivity can be easily adapted to any standard PCR protocol aimed at amplifying circular supercoiled genomes. Apart from its application in the development of sensitive clinical diagnostic PCR assays for a large number of organisms, this method could also prove to be very useful in simplifying the existing protocols for other applications where pre-PCR restriction digestion is required, such as mutation detection, genotyping, and selective template amplification.
Faulds-Pain, Alexandra; Twine, Susan M; Vinogradov, Evgeny; Strong, Philippa C R; Dell, Anne; Buckley, Anthony M; Douce, Gillian R; Valiente, Esmeralda; Logan, Susan M; Wren, Brendan W
C lostridium difficile is a prominent nosocomial pathogen, proliferating and causing enteric disease in individuals with a compromised gut microflora. We characterized the post-translational modification of flagellin in C . difficile 630. The structure of the modification was solved by nuclear magnetic resonance and shown to contain an N-acetylglucosamine substituted with a phosphorylated N-methyl-l-threonine. A reverse genetics approach investigated the function of the putative four-gene mod...
Best, E L; Sandoe, J A T; Wilcox, M H
Toilet facilities in healthcare settings vary widely, but patient toilets are commonly shared and do not have lids. When a toilet is flushed without the lid closed, aerosol production may lead to surface contamination within the toilet environment. To substantiate the risks of airborne dissemination of C. difficile following flushing a toilet, in particular when lids are not fitted. We performed in-situ testing, using faecal suspensions of C. difficile to simulate the bacterial burden found during disease, to measure C. difficile aerosolization. We also measured the extent of splashing occurring during flushing of two different toilet types commonly used in hospitals. C. difficile was recoverable from air sampled at heights up to 25 cm above the toilet seat. The highest numbers of C. difficile were recovered from air sampled immediately following flushing, and then declined 8-fold after 60 min and a further 3-fold after 90 min. Surface contamination with C. difficile occurred within 90 min after flushing, demonstrating that relatively large droplets are released which then contaminate the immediate environment. The mean numbers of droplets emitted upon flushing by the lidless toilets in clinical areas were 15-47, depending on design. C. difficile aerosolization and surrounding environmental contamination occur when a lidless toilet is flushed. Lidless conventional toilets increase the risk of C. difficile environmental contamination, and we suggest that their use is discouraged, particularly in settings where CDI is common. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Tabaqchali, S.; O' Farrell, S.; Holland, D.; Silman, R.
A typing method for Clostridium difficile based on the incorporation of (/sup 35/S)methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile.
Full Text Available We report a case of ulcerative colitis (UC and recurrent Clostridium difficile infection (CDI where the patient was on immunomodulatory therapy and had successful CDI eradication after fecal transplantation. This is the first case report in the literature documenting successful C. difficile eradication in an immunosuppressed patient. We feel that fecal transplantation should be studied as a treatment option in these patients.
David M. Goldfarb
Full Text Available Background. Little is known about the microbiology of diarrhoeal disease in Canada's Arctic regions. There are a number of limitations of conventional microbiology testing techniques for diarrhoeal pathogens, and these may be further compromised in the Arctic, given the often long distances for specimen transport. Objective. To develop a novel multiple-target nanolitre real-time reverse transcriptase (RT-PCR platform to simultaneously test diarrhoeal specimens collected from residents of the Qikiqtani (Baffin Island Region of Nunavut, Canada, for a wide range of bacterial, parasitic and viral agents. Study design/methods. Diarrhoeal stool samples submitted for bacterial culture to Qikiqtani General Hospital in Nunavut over an 18-month period were tested with a multiple-target nanolitre real-time PCR panel for major diarrhoeal pathogens including 8 bacterial, 6 viral and 2 parasitic targets. Results. Among 86 stool specimens tested by PCR, a total of 50 pathogens were detected with 1 or more pathogens found in 40 (46.5% stool specimens. The organisms detected comprised 17 Cryptosporidium spp., 5 Clostridium difficile with toxin B, 6 Campylobacter spp., 6 Salmonella spp., 4 astroviruses, 3 noroviruses, 1 rotavirus, 1 Shigella spp. and 1 Giardia spp. The frequency of detection by PCR and bacterial culture was similar for Salmonella spp., but discrepant for Campylobacter spp., as Campylobacter was detected by culture from only 1/86 specimens. Similarly, Cryptosporidium spp. was detected in multiple samples by PCR but was not detected by microscopy or enzyme immunoassay. Conclusions. Cryptosporidium spp., Campylobacter spp. and Clostridium difficile may be relatively common but possibly under-recognised pathogens in this region. Further study is needed to determine the regional epidemiology and clinical significance of these organisms. This method appears to be a useful tool for gastrointestinal pathogen research and may also be helpful for clinical
Yang, Hsiao-Ting; Chen, Jenn-Wei; Rathod, Jagat; Jiang, Yu-Zhen; Tsai, Pei-Jane; Hung, Yuan-Pin; Ko, Wen-Chien; Paredes-Sabja, Daniel; Huang, I-Hsiu
Clostridium difficile is a Gram-positive, spore-forming anaerobic human gastrointestinal pathogen. C. difficile infection (CDI) is a major health concern worldwide, with symptoms ranging from diarrhea to pseudomembranous colitis, toxic megacolon, sepsis, and death. CDI onset and progression are mostly caused by intestinal dysbiosis and exposure to C. difficile spores. Current treatment strategies include antibiotics; however, antibiotic use is often associated with high recurrence rates and an increased risk of antibiotic resistance. Medium-chain fatty acids (MCFAs) have been revealed to inhibit the growth of multiple human bacterial pathogens. Components of coconut oil, which include lauric acid, have been revealed to inhibit C. difficile growth in vitro . In this study, we demonstrated that lauric acid exhibits potent antimicrobial activities against multiple toxigenic C. difficile isolates in vitro . The inhibitory effect of lauric acid is partly due to reactive oxygen species (ROS) generation and cell membrane damage. The administration of lauric acid considerably reduced biofilm formation and preformed biofilms in a dose-dependent manner. Importantly, in a mouse infection model, lauric acid pretreatment reduced CDI symptoms and proinflammatory cytokine production. Our combined results suggest that the naturally occurring MCFA lauric acid is a novel C. difficile inhibitor and is useful in the development of an alternative or adjunctive treatment for CDI.
Davis, Manli Y; Zhang, Husen; Brannan, Lera E; Carman, Robert J; Boone, James H
Clostridium difficile is the most common known cause of antibiotic-associated diarrhea. Upon the disturbance of gut microbiota by antibiotics, C. difficile establishes growth and releases toxins A and B, which cause tissue damage in the host. The symptoms of C. difficile infection disease range from mild diarrhea to pseudomembranous colitis and toxic megacolon. Interestingly, 10-50 % of infants are asymptomatic carriers of C. difficile. This longitudinal study of the C. difficile colonization in an infant revealed the dynamics of C. difficile presence in gut microbiota. Fifty fecal samples, collected weekly between 5.5 and 17 months of age from a female infant who was an asymptomatic carrier of C. difficile, were analyzed by 16S rRNA gene sequencing. Colonization switching between toxigenic and non-toxigenic C. difficile strains as well as more than 100,000-fold fluctuations of C. difficile counts were observed. C. difficile toxins were detected during the testing period in some infant stool samples, but the infant never had diarrhea. Although fecal microbiota was stable during breast feeding, a dramatic and permanent change of microbiota composition was observed within 5 days of the transition from human milk to cow milk. A rapid decline and eventual disappearance of C. difficile coincided with weaning at 12.5 months. An increase in the relative abundance of Bacteroides spp., Blautia spp., Parabacteroides spp., Coprococcus spp., Ruminococcus spp., and Oscillospira spp. and a decrease of Bifidobacterium spp., Lactobacillus spp., Escherichia spp., and Clostridium spp. were observed during weaning. The change in microbiome composition was accompanied by a gradual increase of fecal pH from 5.5 to 7. The bacterial groups that are less abundant in early infancy, and that increase in relative abundance after weaning, likely are responsible for the expulsion of C. difficile.
Limbago, Brandi; Thompson, Angela D; Greene, Sharon A; MacCannell, Duncan; MacGowan, Charles E; Jolbitado, Beverly; Hardin, Henrietta D; Estes, Stephanie R; Weese, J Scott; Songer, J Glenn; Gould, L Hannah
Three previously described methods for culture of Clostridium difficile from meats were evaluated by microbiologists with experience in C. difficile culture and identification. A consensus protocol using BHI broth enrichment followed by ethanol shock and plating to selective and non-selective media was selected for use, and all participating laboratories received hands-on training in the use of this method prior to study initiation. Retail meat products (N = 1755) were cultured for C. difficile over 12 months during 2010-2011 at 9 U.S. FoodNet sites. No C. difficile was recovered, although other clostridia were isolated. Published by Elsevier Ltd.
Pitz, Adam M; Park, Geun Woo; Lee, David; Boissy, Ying L; Vinjé, Jan
Previous studies have shown bismuth subsalicylate (BSS) has antimicrobial properties, but few studies have addressed the mechanism of action. Furthermore, following BSS ingestion other bismuth salts form throughout the gastrointestinal tract including bismuth oxychloride (BiOCl) that also act upon enteric pathogens. To further understand the antimicrobial activity of bismuth in infectious diarrhea, the antimicrobial effect of BSS and BiOCl on Clostridium difficile, Salmonella, Shigella, Shiga toxin-producing Escherichia coli strains and norovirus (NoV) were measured. Bacterial enteric pathogens in pure culture or in human fecal material were exposed to 35mg/ml BSS or BiOCl with or without a vehicle suspension. BSS and BiOCl treated samples were quantified and visualized by transmission electron microscopy. To measure the effect on NoV, reduction of infectious murine NoV (MNV), a surrogate for human NoV, and Norwalk virus RNA levels were measured by viral plaque assay and RT-qPCR, respectively. BSS and BiOCl reduced bacterial growth by 3-9 logs in all strains with majority resulting in populations of bismuth on bacterial membranes and within the bacterial organisms at 30 min post-treatment. At 8.8mg/ml BSS and BiOCl reduced infectivity of MNV significantly by 2.7 and 2.0 log after 24 h of exposure. In addition, both BSS and BiOCl slightly reduced the level of Norwalk replicon-bearing cells suggesting that bismuth may inhibit NoV in vivo. Collectively, our results confirm and build on existing data that BSS has antimicrobial properties against a wide-range of diarrhea-causing pathogens.
The Prevessin Control Room during LEP's start up in 1989. The Prévessin Control Room (PCR) was recently engulfed in a wave of nostalgia. The PCR, scene of some of the greatest moments in CERN's history, is being dismantled to prepare for a complete overhaul. In February 2006, a new combined control centre for all the accelerators will open its doors on the same site, together with a new building currently under construction (see Bulletin issue 27/2004 of 28 June 2004). This marks the end of an important chapter in CERN's history. The Prévessin Control Room saw its first momentous event 28 years ago when the 400 GeV beam for the SPS was commissioned in the presence of Project Leader John Adams. It was also here that the first proton-antiproton collisions were observed, in 1981. Eight years later, in 1989, operators and directors alike jumped for joy at the announcement of the first electron-positron collisions at the start up of LEP, the biggest accelerator in the world. Today the 80 terminals and PCs have b...
Richard E Nelson
Full Text Available A number of strategies exist to reduce Clostridium difficile (C. difficile transmission. We conducted an economic evaluation of "bundling" these strategies together.We constructed an agent-based computer simulation of nosocomial C. difficile transmission and infection in a hospital setting. This model included the following components: interactions between patients and health care workers; room contamination via C. difficile shedding; C. difficile hand carriage and removal via hand hygiene; patient acquisition of C. difficile via contact with contaminated rooms or health care workers; and patient antimicrobial use. Six interventions were introduced alone and "bundled" together: (a aggressive C. difficile testing; (b empiric isolation and treatment of symptomatic patients; (c improved adherence to hand hygiene and (d contact precautions; (e improved use of soap and water for hand hygiene; and (f improved environmental cleaning. Our analysis compared these interventions using values representing 3 different scenarios: (1 base-case (BASE values that reflect typical hospital practice, (2 intervention (INT values that represent implementation of hospital-wide efforts to reduce C. diff transmission, and (3 optimal (OPT values representing the highest expected results from strong adherence to the interventions. Cost parameters for each intervention were obtained from published literature. We performed our analyses assuming low, normal, and high C. difficile importation prevalence and transmissibility of C. difficile.INT levels of the "bundled" intervention were cost-effective at a willingness-to-pay threshold of $100,000/quality-adjusted life-year in all importation prevalence and transmissibility scenarios. OPT levels of intervention were cost-effective for normal and high importation prevalence and transmissibility scenarios. When analyzed separately, hand hygiene compliance, environmental decontamination, and empiric isolation and treatment were the
Vindigni, Stephen M; Broussard, Elizabeth K; Surawicz, Christina M
Clostridium difficile infection is increasingly common with a high risk of recurrence despite antibiotic treatment. In cases of recurrent C. difficile infection, fecal microbiota transplant (FMT) is a highly effective treatment option promoting the restoration of normal gut microbiota. Furthermore, preliminary uncontrolled evidence demonstrates possible benefit of FMT in the management of some cases of inflammatory bowel disease and chronic constipation. In addition to presenting an overview of FMT, we discuss the role of probiotics, a more common approach to modifying the intestinal microbiome. Probiotics have been utilized broadly for many disease processes, including gastrointestinal, cardiovascular and allergic disease settings, although with limited and inconsistent results. Multiple potential areas for research are also identified.
Schoster, A.; Kokotovic, Branko; Permin, Anders
of this study was to examine the in vitro inhibitory effects of selected commercial bacterial strains on pathogenic clostridia and their growth characteristics under simulated gastrointestinal conditions.The inhibitory effects of 17 commercial strains of Lactobacillus (n = 16) and Bifidobacterium (n = 1......Probiotics have gained importance in human and veterinary medicine to prevent and control clostridial enteric disease. Limited information is available on the ability of different probiotic bacteria used in food products to inhibit Clostridium difficile and Clostridium perfringens. The objective......) on the reference strains of C. difficile and C. perfringens were assessed by an agar well diffusion assay and by a broth culture inhibition assay using cell-free supernatant harvested at different growth phases, with and without pH neutralization. To study growth characteristics, probiotic strains were cultivated...
Full Text Available Dima Youssef,1 William B Grant,2 Alan N Peiris3,41Department of Internal Medicine, Division of Infectious Diseases, 2Sunlight, Nutrition and Health Research Center, San Francisco, CA USA; 3Department of Medicine, Mountain Home VAMC, 4Department of Medicine, East Tennessee State University, Johnson City, Tennessee, USAIn the July 3, 2012 issue of the journal of Risk Management and Healthcare Policy, Martinez et al present a nice review on Clostridium difficile (C. difficile infections.1 The different manifestations of this challenging disease along with the high cost and burden on the health care system were discussed. While the authors did an admirable job in discussing traditional risk factors, they do not mention vitamin D deficiency.View original paper by Martinez and colleagues.
Zhang, Han; Liu, Xiwang; Yang, Yajun; Li, Jianyong
Quantitative structure activity relationship (QSAR) has been established between the various physiochemical parameters of a series of nitazoxanide-based analogues and its antibacterial activity against Clostridium difficile. Genetic function approximation (GFA) and comparative molecular field analysis (CoMFA) techniques were used to identify the descriptors that have influence on biological activity. The most influencing molecular descriptors identified in 2D-QSAR include spatial, topological, and electronic descriptors, while electrostatic and stereoscopic fields were the most influencing molecular descriptors identified in 3D-QSAR. Statistical qualities (r2, q2) indicated the significance and predictability of the developed models. The study indicated that antibacterial activity of Clostridium difficile can be improved by increasing molecular connectivity index, local charge surface index, sharp index and decreasing molecular flexibility index.
Edmond, Michael B
The human gut is colonized with 200 to 1,000 bacterial species. Administration of antibiotics reduces the diversity of the intestinal microbiota, reduces colonization resistance, and can lead to infection with Clostridium difficile . These infections have become more prevalent and increasingly patients are experiencing multiple recurrences that are incurable with standard treatment. Although fecal microbiota transplantation (FMT) has been used for centuries in human and veterinary medicine, only recently has it be shown to be highly effective for recurrent C. difficile infection. The goal of FMT is to re-introduce a complete, stable community of gut microorganisms to repair or replace the disrupted native microbiota. FMT can be delivered via nasoenteric tube, colonoscopy, or enema. Despite a cure rate approximating 90%, many barriers to FMT have limited its availability to patients. The recent development of a not-for-profit stool bank has helped to make this therapy more accessible. Additional indications for FMT are currently under investigation.
Riedel, Thomas; Wittmann, Johannes; Bunk, Boyke; Schober, Isabel; Spröer, Cathrin; Gronow, Sabine; Overmann, Jörg
Pathogenic clostridia typically produce toxins as virulence factors which cause severe diseases in both humans and animals. Whereas many clostridia like e.g., Clostridium perfringens, Clostridium botulinum or Clostridium tetani were shown to contain toxin-encoding plasmids, only toxin genes located on the chromosome were detected in Clostridioides difficile so far. In this study, we determined, annotated, and analyzed the complete genome of the bacteriophage phiSemix9P1 using single-molecule real-time sequencing technology (SMRT). To our knowledge, this represents the first C. difficile-associated bacteriophage genome that carries a complete functional binary toxin locus in its genome. Copyright © 2017 Elsevier B.V. All rights reserved.
Buckley, Anthony M.; Jukes, Caitlin; Candlish, Denise; Irvine, June J.; Spencer, Janice; Fagan, Robert P.; Roe, Andrew J.; Christie, John M.; Fairweather, Neil F.; Douce, Gillian R.
The uses of fluorescent reporters derived from green fluorescent protein have proved invaluable for the visualisation of biological processes in bacteria grown under aerobic conditions. However, their requirement for oxygen has limited their application in obligate anaerobes such as Clostridium difficile. Fluorescent proteins derived from Light, Oxygen or Voltage sensing (LOV) domains have been shown to bridge this limitation, but their utility as translational fusions to monitor protein expr...
Spinler, Jennifer K; Brown, Aaron; Ross, Caná L; Boonma, Prapaporn; Conner, Margaret E; Savidge, Tor C
Lifeway(®) kefir, a fermented milk product containing 12 probiotic organisms, is reported to show promise as an alternative to fecal microbiota transplantation for recurrent Clostridium difficile infection (CDI). We employed a murine CDI model to study the probiotic protective mechanisms and unexpectedly determined that kefir drastically increased disease severity. Our results emphasize the need for further independent clinical testing of kefir as alternative therapy in recurrent CDI. Copyright © 2016 Elsevier Ltd. All rights reserved.
Nerandzic, Michelle M.; Donskey, Curtis J.
Background Chlorhexidine is a broad-spectrum antimicrobial commonly used to disinfect the skin of patients to reduce the risk of healthcare-associated infections. Because chlorhexidine is not sporicidal, it is not anticipated that it would have an impact on skin contamination with Clostridium difficile, the most important cause of healthcare-associated diarrhea. However, although chlorhexidine is not sporicidal as it is used in healthcare settings, it has been reported to kill spores of Bacillus species under altered physical and chemical conditions that disrupt the spore’s protective barriers (e.g., heat, ultrasonication, alcohol, or elevated pH). Here, we tested the hypothesis that similarly altered physical and chemical conditions result in enhanced sporicidal activity of chlorhexidine against C. difficile spores. Principal Findings C. difficile spores became susceptible to heat killing at 80°C within 15 minutes in the presence of chlorhexidine, as opposed to spores suspended in water which remained viable. The extent to which the spores were reduced was directly proportional to the concentration of chlorhexidine in solution, with no viable spores recovered after 15 minutes of incubation in 0.04%–0.0004% w/v chlorhexidine solutions at 80°C. Reduction of spores exposed to 4% w/v chlorhexidine solutions at moderate temperatures (37°C and 55°C) was enhanced by the presence of 70% ethanol. However, complete elimination of spores was not achieved until 3 hours of incubation at 55°C. Elevating the pH to ≥9.5 significantly enhanced the killing of spores in either aqueous or alcoholic chlorhexidine solutions. Conclusions Physical and chemical conditions that alter the protective barriers of C. difficile spores convey sporicidal activity to chlorhexidine. Further studies are necessary to identify additional agents that may allow chlorhexidine to reach its target within the spore. PMID:25861057
EpiData Center Department FMT fecal microbiota transplantation FDA Food and Drug Administration GI gastrointestinal GDH glutamate dehydrogenase...In February 2012, the US Food and Drug Administration (FDA) informed the public that proton pump inhibitors (PPIs) may be associated with an...increased risk of C. difficile-associated diarrhea.17 PPIs decrease gastric acidity ( pH ), which provides pathogens the opportunity to colonize the
Andersen, Kasper Krogh; Strokappe, Nika M.; Hultberg, Anna; Truusalu, Kai; Smidt, Imbi; Mikelsaar, Raik-Hiio; Mikelsaar, Marika; Verrips, Theo; Hammarström, Lennart
Clostridium difficile is the primary cause of nosocomial antibiotic-associated diarrhea in the Western world. The major virulence factors of C. difficile are two exotoxins, toxin A (TcdA) and toxin B (TcdB), which cause extensive colonic inflammation and epithelial damage manifested by episodes of diarrhea. In this study, we explored the basis for an oral antitoxin strategy based on engineered Lactobacillus strains expressing TcdB-neutralizing antibody fragments in the gastrointestinal tract. Variable domain of heavy chain-only (VHH) antibodies were raised in llamas by immunization with the complete TcdB toxin. Four unique VHH fragments neutralizing TcdB in vitro were isolated. When these VHH fragments were expressed in either secreted or cell wall-anchored form in Lactobacillus paracasei BL23, they were able to neutralize the cytotoxic effect of the toxin in an in vitro cell-based assay. Prophylactic treatment with a combination of two strains of engineered L. paracasei BL23 expressing two neutralizing anti-TcdB VHH fragments (VHH-B2 and VHH-G3) delayed killing in a hamster protection model where the animals were challenged with spores of a TcdA− TcdB+ strain of C. difficile (P survived until the termination of the experiment at day 5 and showed either no damage or limited inflammation of the colonic mucosa despite having been colonized with C. difficile for up to 4 days. The protective effect in the hamster model suggests that the strategy could be explored as a supplement to existing therapies for patients. PMID:26573738
Adams, Hannah M.; Li, Xiang; Mascio, Carmela; Chesnel, Laurent; Palmer, Kelli L.
Clostridium difficile infection (CDI) is an urgent public health concern causing considerable clinical and economic burdens. CDI can be treated with antibiotics, but recurrence of the disease following successful treatment of the initial episode often occurs. Surotomycin is a rapidly bactericidal cyclic lipopeptide antibiotic that is in clinical trials for CDI treatment and that has demonstrated superiority over vancomycin in preventing CDI relapse. Surotomycin is a structural analogue of the...
Sachdeva, Meena; Leeds, Jennifer A.
LFF571 is a novel semisynthetic thiopeptide antibacterial that is undergoing investigation for safety and efficacy in patients with moderate Clostridium difficile infections. LFF571 inhibits bacterial protein synthesis by interacting with elongation factor Tu (EF-Tu) and interrupting complex formation between EF-Tu and aminoacyl-tRNA. Given this mechanism of action, we hypothesized that concentrations of LFF571 below those necessary to inhibit bacterial growth would reduce steady-state toxin ...
Sharps disposal containers are ubiquitous in health care facilities; however, there is paucity of data on their potential role in pathogen transmission. This study assessed the relationship between use of single-use versus reusable sharps containers and rates of Clostridium difficile infections in a national sample of hospitals. A 2013 survey of 1,990 hospitals collected data on the use of sharps containers. Responses were linked to the 2012 Medicare Provider Analysis and Review dataset. Bivariate and multivariable negative binomial regression were conducted to examine differences in C difficile rates between hospitals using single-use versus reusable containers. There were 604 hospitals who completed the survey; of these, 539 provided data on use of sharps containers in 2012 (27% response rate). Hospitals had, on average, 289 beds (SD ± 203) and were predominantly non-for-profit (67%) and nonteaching (63%). Most used reusable sharps containers (72%). In bivariate regression, hospitals using single-use containers had significantly lower rates of C difficile versus hospitals using reusable containers (incidence rate ratio [IRR] = 0.846, P = .001). This relationship persisted in multivariable regression (IRR = 0.870, P = .003) after controlling for other hospital characteristics. This is the first study to show a link between use of single-use sharps containers and lower C difficile rates. Future research should investigate the potential for environmental contamination of reusable containers and the role they may play in pathogen transmission. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Mayer, Melinda J.; Garefalaki, Vasiliki; Spoerl, Rebecca; Narbad, Arjan; Meijers, Rob
Endolysin CD27L causes cell lysis of the pathogen Clostridium difficile, a major cause of nosocomial infection. We report a structural and functional analysis of the catalytic activity of CD27L against C. difficile and other bacterial strains. We show that truncation of the endolysin to the N-terminal domain, CD27L1–179, gave an increased lytic activity against cells of C. difficile, while the C-terminal region, CD27L180–270, failed to produce lysis. CD27L1–179 also has increased activity against other bacterial species that are targeted by the full-length protein and in addition was able to lyse some CD27L-insensitive strains. However, CD27L1–179 retained a measure of specificity, failing to lyse a wide range of bacteria. The use of green fluorescent protein (GFP)-labeled proteins demonstrated that both CD27L and CD27L1–179 bound to C. difficile cell walls. The crystal structure of CD27L1–179 confirms that the enzyme is a zinc-dependent N-acetylmuramoyl-l-alanine amidase. A structure-based sequence analysis allowed us to identify four catalytic residues, a proton relay cascade, and a substrate binding pocket. A BLAST search shows that the closest-related amidases almost exclusively target Clostridia. This implied that the catalytic domain alone contained features that target a specific bacterial species. To test this hypothesis, we modified Leu 98 to a Trp residue which is found in an endolysin from a bacteriophage of Listeria monocytogenes (PlyPSA). This mutation in CD27L resulted in an increased activity against selected serotypes of L. monocytogenes, demonstrating the potential to tune the species specificity of the catalytic domain of an endolysin. PMID:21803993
Mayer, Melinda J; Garefalaki, Vasiliki; Spoerl, Rebecca; Narbad, Arjan; Meijers, Rob
Endolysin CD27L causes cell lysis of the pathogen Clostridium difficile, a major cause of nosocomial infection. We report a structural and functional analysis of the catalytic activity of CD27L against C. difficile and other bacterial strains. We show that truncation of the endolysin to the N-terminal domain, CD27L1-179, gave an increased lytic activity against cells of C. difficile, while the C-terminal region, CD27L180-270, failed to produce lysis. CD27L1-179 also has increased activity against other bacterial species that are targeted by the full-length protein and in addition was able to lyse some CD27L-insensitive strains. However, CD27L1-179 retained a measure of specificity, failing to lyse a wide range of bacteria. The use of green fluorescent protein (GFP)-labeled proteins demonstrated that both CD27L and CD27L1-179 bound to C. difficile cell walls. The crystal structure of CD27L1-179 confirms that the enzyme is a zinc-dependent N-acetylmuramoyl-l-alanine amidase. A structure-based sequence analysis allowed us to identify four catalytic residues, a proton relay cascade, and a substrate binding pocket. A BLAST search shows that the closest-related amidases almost exclusively target Clostridia. This implied that the catalytic domain alone contained features that target a specific bacterial species. To test this hypothesis, we modified Leu 98 to a Trp residue which is found in an endolysin from a bacteriophage of Listeria monocytogenes (PlyPSA). This mutation in CD27L resulted in an increased activity against selected serotypes of L. monocytogenes, demonstrating the potential to tune the species specificity of the catalytic domain of an endolysin.
EDMOND, MICHAEL B.
The human gut is colonized with 200 to 1,000 bacterial species. Administration of antibiotics reduces the diversity of the intestinal microbiota, reduces colonization resistance, and can lead to infection with Clostridium difficile. These infections have become more prevalent and increasingly patients are experiencing multiple recurrences that are incurable with standard treatment. Although fecal microbiota transplantation (FMT) has been used for centuries in human and veterinary medicine, on...
Fuhr, J.E.; Trent, D.J.; Collmann, I.R.
Detection and identification of Clostridium difficile toxin by traditional monolayer assay were compared with results obtained by a new procedure based on toxin-dependent inhibition of target cell uptake of a radioactive nucleoside. A high degree of correlation was noted between the two determinations. Although the new procedure was quantitative and objective, its value is seen at present as a rapid screen that may support results obtained in monolayers and as a potential assay for other, currently unidentified, toxins.
Daneman, N; Guttmann, A; Wang, X; Ma, X; Gibson, D; Stukel, T A
Clostridium difficile is the most common cause of healthcare-acquired infection; the real-world impacts of some proposed C. difficile prevention processes are unknown. We conducted a population-based retrospective cohort study of all patients admitted to acute care hospitals between April 2011 and March 2012 in Ontario, Canada. Hospital prevention practices were determined by survey of infection control programmes; responses were linked to patient-level risk factors and C. difficile outcomes in Ontario administrative databases. Multivariable generalised estimating equation (GEE) regression models were used to assess the impact of selected understudied hospital prevention processes on the patient-level risk of C. difficile infection, accounting for patient risk factors, baseline C. difficile rates and structural hospital characteristics. C. difficile infections complicated 2341 of 653 896 admissions (3.6 per 1000 admissions). Implementation of the selected C. difficile prevention practices was variable across the 159 hospitals with isolation of all patients at onset of diarrhoea reported by 43 (27%), auditing of antibiotic stewardship compliance by 26 (16%), auditing of cleaning practices by 115 (72%), on-site diagnostic testing by 74 (47%), vancomycin as first-line treatment by 24 (15%) and reporting rates to senior leadership by 52 (33%). None of these processes were associated with a significantly reduced risk of C. difficile after adjustment for baseline C. difficile rates, structural hospital characteristics and patient-level factors. Patient-level factors were strongly associated with C. difficile risk, including age, comorbidities, non-elective and medical admissions. In the largest study to date, selected hospital prevention strategies were not associated with a statistically significant reduction in patients' risk of C. difficile infection. These prevention strategies have either limited effectiveness or were ineffectively implemented during the study
Full Text Available Clostridium difficile causes antibiotic-associated diarrhea and pseudomembranous colitis by production of the Rho GTPase-glucosylating toxins A and B. Recently emerging hypervirulent Clostridium difficile strains additionally produce the binary ADP-ribosyltransferase toxin CDT (Clostridium difficile transferase, which ADP-ribosylates actin and inhibits actin polymerization. Thus far, the role of CDT as a virulence factor is not understood. Here we report by using time-lapse- and immunofluorescence microscopy that CDT and other binary actin-ADP-ribosylating toxins, including Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin, induce redistribution of microtubules and formation of long (up to >150 microm microtubule-based protrusions at the surface of intestinal epithelial cells. The toxins increase the length of decoration of microtubule plus-ends by EB1/3, CLIP-170 and CLIP-115 proteins and cause redistribution of the capture proteins CLASP2 and ACF7 from microtubules at the cell cortex into the cell interior. The CDT-induced microtubule protrusions form a dense meshwork at the cell surface, which wrap and embed bacterial cells, thereby largely increasing the adherence of Clostridia. The study describes a novel type of microtubule structure caused by less efficient microtubule capture and offers a new perspective for the pathogenetic role of CDT and other binary actin-ADP-ribosylating toxins in host-pathogen interactions.
Leber, Andrew; Hontecillas, Raquel; Abedi, Vida; Tubau-Juni, Nuria; Zoccoli-Rodriguez, Victoria; Stewart, Caroline; Bassaganya-Riera, Josep
The current treatment paradigm in Clostridium difficile infection is the administration of antibiotics contributing to the high rates of recurrent infections. Recent alternative strategies, such as fecal microbiome transplantation and anti-toxin antibodies, have shown similar efficacy in the treatment of C. difficile associated disease (CDAD). However, barriers exist for either treatment or other novel treatments to displace antibiotics as the standard of care. To aid in the comparison of these and future treatments in CDAD, we developed an in silico pipeline to predict clinical efficacy with nonclinical results. The pipeline combines an ordinary differential equation (ODE)-based model, describing the immunological and microbial interactions in the gastrointestinal (GI) mucosa, with machine learning algorithms to translate simulated output quantities (i.e. time of clearance, quantity of commensal bacteria, T cell ratios) into clinical predictions based on prior preclinical, translational and clinical trial data. As a use case, we compare the efficacy of lanthionine synthetase C-like 2 (LANCL2), a novel immunoregulatory target with promising efficacy in inflammatory bowel disease (IBD), activation with antibiotics, fecal microbiome transplantation and anti-toxin antibodies in the treatment of CDAD. We further validate the potential of LANCL2 pathway activation, in a mouse model of C. difficile infection in which it displays an ability to decrease weight loss and inflammatory cell types while protecting against mortality. The computational pipeline can serve as an important resource in the development of new treatment modalities. Copyright © 2017 Elsevier B.V. All rights reserved.
Lv, Z; Peng, G L; Su, J R
Clostridium difficile is the most common cause of hospital-acquired diarrhea in patients treated with antibiotics, chemotherapeutic agents, and other drugs that alter the normal equilibrium of the intestinal flora. A better understanding of the risk factors for C. difficile-associated disease (CDAD) could be used to reduce the incidence of CDAD and the costs associated with its treatment. The aim of this study was to identify the risk factors for CDAD in a cohort of Chinese patients in a Beijing hospital. Medical charts of a total of 130 inpatients (62 males and 68 females) with hospital-acquired diarrhea (45 with CDAD; 85 without CDAD) were retrospectively reviewed. C. difficile toxins A and B were detected in fecal samples using enzyme-linked fluorescence assays. The drugs used by patients with and without CDAD before the onset of diarrhea were compared. Factors that differed significantly between the two groups by univariate analysis were analyzed by multivariate analysis using a logistic regression model. Multivariate analysis showed that cephalosporin treatment was associated with a significantly higher risk of CDAD in hospitalized patients, while treatment with glycopeptides was significantly associated with a reduction in CDAD (Passociated with CDAD compared to individuals using other CDAD-related drugs. Additionally, we showed that treatment with glycopeptides was negatively associated with CDAD, compared to individuals using other CDAD-related drugs.
He, Miao; Miyajima, Fabio; Roberts, Paul; Ellison, Louise; Pickard, Derek J; Martin, Melissa J; Connor, Thomas R; Harris, Simon R; Fairley, Derek; Bamford, Kathleen B; D'Arc, Stephanie; Brazier, Jon; Brown, Derek; Coia, John E; Douce, Gill; Gerding, Dale; Kim, Hee Jung; Koh, Tse Hsien; Kato, Haru; Senoh, Mitsutoshi; Louie, Tom; Michell, Stephen; Butt, Emma; Peacock, Sharon J; Brown, Nick M; Riley, Tom; Songer, Glen; Wilcox, Mark; Pirmohamed, Munir; Kuijper, Ed; Hawkey, Peter; Wren, Brendan W; Dougan, Gordon; Parkhill, Julian; Lawley, Trevor D
Epidemic C. difficile (027/BI/NAP1) has rapidly emerged in the past decade as the leading cause of antibiotic-associated diarrhea worldwide. However, the key events in evolutionary history leading to its emergence and the subsequent patterns of global spread remain unknown. Here, we define the global population structure of C. difficile 027/BI/NAP1 using whole-genome sequencing and phylogenetic analysis. We show that two distinct epidemic lineages, FQR1 and FQR2, not one as previously thought, emerged in North America within a relatively short period after acquiring the same fluoroquinolone resistance-conferring mutation and a highly related conjugative transposon. The two epidemic lineages showed distinct patterns of global spread, and the FQR2 lineage spread more widely, leading to healthcare-associated outbreaks in the UK, continental Europe and Australia. Our analysis identifies key genetic changes linked to the rapid transcontinental dissemination of epidemic C. difficile 027/BI/NAP1 and highlights the routes by which it spreads through the global healthcare system.
Full Text Available The pathogenesis of Clostridium difficile, the major cause of antibiotic-associated diarrhea, is mainly associated with the production and activities of two major toxins. In many bacteria, toxins are released into the extracellular environment via the general secretion pathways. C. difficile toxins A and B have no export signature and their secretion is not explainable by cell lysis, suggesting that they might be secreted by an unusual mechanism. The TcdE protein encoded within the C. difficile pathogenicity locus (PaLoc has predicted structural features similar to those of bacteriophage holin proteins. During many types of phage infection, host lysis is driven by an endolysin that crosses the cytoplasmic membrane through a pore formed by holin oligomerization. We demonstrated that TcdE has a holin-like activity by functionally complementing a λ phage deprived of its holin. Similar to λ holin, TcdE expressed in Escherichia coli and C. difficile formed oligomers in the cytoplamic membrane. A C. difficile tcdE mutant strain grew at the same rate as the wild-type strain, but accumulated a dramatically reduced amount of toxin proteins in the medium. However, the complemented tcdE mutant released the toxins efficiently. There was no difference in the abundance of tcdA and tcdB transcripts or of several cytoplasmic proteins in the mutant and the wild-type strains. In addition, TcdE did not overtly affect membrane integrity of C. difficile in the presence of TcdA/TcdB. Thus, TcdE acts as a holin-like protein to facilitate the release of C. difficile toxins to the extracellular environment, but, unlike the phage holins, does not cause the non-specific release of cytosolic contents. TcdE appears to be the first example of a bacterial protein that releases toxins into the environment by a phage-like system.
Denman, S.E.; McSweeney, C.S.
Many nucleic acid-based probe and PCR assays have been developed for the detection tracking of specific microbes within the rumen ecosystem. Conventional PCR assays detect PCR products at the end stage of each PCR reaction, where exponential amplification is no longer being achieved. This approach can result in different end product (amplicon) quantities being generated. In contrast, using quantitative, or real-time PCR, quantification of the amplicon is performed not at the end of the reaction, but rather during exponential amplification, where theoretically each cycle will result in a doubling of product being created. For real-time PCR, the cycle at which fluorescence is deemed to be detectable above the background during the exponential phase is termed the cycle threshold (Ct). The Ct values obtained are then used for quantitation, which will be discussed later
PCR represents an extremely powerful and central molecular biology method. At the heart of its power is the exquisite sensitivity offered: single molecule detection in certain contexts. However, with great power comes great responsibility. Contamination of reagents or test samples with amplifiable material, such as previous reaction products, can be crippling to scientists applying PCR protocols. Prevention of PCR contamination is far and away preferred over eradication. This chapter sets out to offer guidance as to how to use PCR while minimising contamination problems.
Jalanka, Jonna; Mattila, Eero; Jouhten, Hanne; Hartman, Jorn; Vos, de Willem M.; Arkkila, Perttu; Satokari, Reetta
Background: Faecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection (rCDI). It restores the disrupted intestinal microbiota and subsequently suppresses C. difficile. The long-term stability of the intestinal microbiota and the recovery of
Søes, Lillian Marie; Holt, H M; Böttiger, B
Clostridium difficile infection (CDI) is gradually being recognised as a cause of morbidity in the community. We investigated the incidence and clinical characteristics of CDI in a community setting and characterised the C. difficile strains by toxin gene profiling and polymerase chain reaction...
Clayton, Evelyn M
Comorbidity with Clostridium difficile may cause diagnostic delay in newly presenting inflammatory bowel disease (IBD) patients, trigger relapse in established disease, confound therapies, and serve as an indicator of an underlying defect in innate immunity. Retrospective analyses have suggested community acquisition; to address this we conducted a prospective analysis of C. difficile carriage in IBD patients using molecular methods specifically in an outpatient setting.
Full Text Available Clostridium difficile colitis, although rare, could represent a serious complication following chemotherapy. Prior antibiotic use has been considered the single most important risk factor in the development of C. difficile infection. Recently, the association between antineoplastic therapy and C. difficile-associated diarrhea in the absence of a prior antibiotic therapy has become more apparent. A 75-year-old woman with serous adenocarcinoma of the ovary developed lethal pancolitis caused by C. difficile after five cycles of paclitaxel- and carboplatin-based chemotherapy. She presented with diarrhea, coffee-ground emesis, and oliguria and was hospitalized immediately for aggressive treatment. Despite all the medical efforts, her condition worsened and she died after twenty days. We describe the second case reported of a patient developing a severe C. difficile colitis following chemotherapy without any recent antibiotic use and review the data of the literature, emphasizing the need to a prompt diagnosis and management that can significantly decrease the morbidity and life-threatening complications associated with this infection.
Meader, Emma; Mayer, Melinda J; Gasson, Michael J; Steverding, Dietmar; Carding, Simon R; Narbad, Arjan
Clostridium difficile is primarily a nosocomial pathogen, causing thousands of cases of antibiotic-associated diarrhoea in the UK each year. In this study, we used a batch fermentation model of a C. difficile colonised system to evaluate the potential of a prophylactic and a remedial bacteriophage treatment regime to control the pathogen. It is shown that the prophylaxis regime was effective at preventing the growth of C. difficile (p = viable C. difficile cells (p = <0.0001), but still resulted in a lower level of toxin production relative to the control. The numbers of commensal bacteria including total aerobes and anaerobes, Bifidobacterium sp., Bacteroides sp., Lactobacillus sp., total Clostridium sp., and Enterobacteriaceae were not significantly decreased by this therapy, whereas significant detrimental effects were observed with metronidazole treatment. Our study indicates that phage therapy has potential to be used for the control of C. difficile; it highlights the main benefits of this approach, and some future challenges. Copyright Â© 2010 Elsevier Ltd. All rights reserved.
Full Text Available Clostridium difficile is considered to be one of the major cause of infectious diarrhea in healthcare systems worldwide. Symptoms of C. difficile infection are caused largely by the production of two cytotoxins: toxin A (TcdA and toxin B (TcdB. Vaccine development is considered desirable as it would decrease the mounting medical costs and mortality associated with C. difficile infections. Biodegradable nanoparticles composed of poly-γ-glutamic acid (γ-PGA and chitosan have proven to be a safe and effective antigen delivery system for many viral vaccines. However, few studies have used this efficient antigen carrier for bacterial vaccine development. In this study, we eliminated the toxin activity domain of toxin B by constructing a recombinant protein rTcdB consists of residues 1852-2363 of TcdB receptor binding domain. The rTcdB was encapsulated in nanoparticles composed of γ-PGA and chitosan. Three rounds of intraperitoneal vaccination led to high anti-TcdB antibody responses and afforded mice full protection mice from lethal dose of C. difficile spore challenge. Protection was associated with high levels of toxin-neutralizing antibodies, and the rTcdB-encapsulated NPs elicited a longer-lasting antibody titers than antigen with the conventional adjuvant, aluminum hydroxide. Significant reductions in the level of proinflammatory cytokines and chemokines were observed in vaccinated mouse. These results suggested that polymeric nanocomplex-based vaccine design can be useful in developing vaccine against C. difficile infections.
Senoh, Mitsutoshi; Kato, Haru; Murase, Tomoko; Hagiya, Hideharu; Tagashira, Yasuaki; Fukuda, Tadashi; Iwaki, Masaaki; Yamamoto, Akihiko; Shibayama, Keigo
The laboratory diagnostic methods for Clostridium difficile infection (CDI) include toxigenic culture, enzyme immunoassays (EIAs) to detect the toxins of C. difficile, and nucleic acid amplification tests (NAATs) to detect C. difficile toxin genes, but each of these methods has disadvantages; toxigenic cultures require a long time to produce results, EIAs have low sensitivity, and NAATs that target DNA cannot distinguish vegetative cells from spores and dead cells. Here we report a new detection method that uses reverse transcription polymerase chain reaction to target the toxin-gene transcripts. This method was able to specifically detect the vegetative cells of toxigenic C. difficile in fecal samples in spike tests, with a minimum detection limit of 5 × 10(2) colony-forming units per 100 mg of stool specimen. The performance of this method was also demonstrated in a pilot scale evaluation using clinical fecal specimens, which showed that this method may be more sensitive than EIA and requires a shorter time than toxigenic culture. This method could potentially be applied in the clinical laboratory to detect C. difficile in fecal specimens. The ability of this method to discriminate the presence of vegetative cells from spores and dead cells could help to further the understanding of CDI. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.
Romanazzi, Valeria; Bonetta, Silvia; Fornasero, Stefania; De Ceglia, Margherita; Gilli, Giorgio; Traversi, Deborah
Wastewater treatment plants (WWTP) are an important source of surface water contamination by enteric pathogens, affecting the role of environmental water as a microbial reservoir. We describe the release to the environment of certain anaerobes of human and environmental concern. The work was focused on emerging microbial targets. They are tracing, by RT-qPCR, on WWTP effluents, both liquid and solid, when an anaerobic digestion step is included. The focus is placed on Clostridium spp. with the specific quantification of Clostridium perfringens, as typical bioindicator, and Clostridium difficile, as emerging pathogen not only confined into nosocomial infection. Moreover methanogens were quantified for their involvement in the anaerobic digestion, and in particular on Methanobrevibacter smithii as major methanogenic component of the human gut microbiome and as not conventional faecal indicator. In the water samples, a reduction, statistically significant, in all microbial targets was observed (p effluents, particularly bio-solids, to reduce the potential release of pathogens into the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Full Text Available With increasing incidence of Clostridium difficile (C. difficile associated diarrhea and pseudomembranous colitis, several extra-intestinal manifestations of the organism have been unmasked which include-bacteremia, brain abscess, pericarditis etc. We report a rare and interesting case of C. difficile bacteremia and subsequent meningitis in a 10 year old child. The child was immune competent, which further raises the question about the virulent possibilities of the organism and its implications in the near future. The condition resulted from a prolonged treatment with intravenous (I.V. cefotaxime for staphylococcal pyogenic arthritis. The child recovered from the septic arthritis but on the 7th day post-admission developed features of bacteremia. The child was later treated with intravenous metronidazole and vancomycin and he was discharged on the 21st day post-admission. No recurrence of symptoms was noted.
Hansen, Lykke H; Vester, Birte
The Cfr RNA methyltransferase causes multiple resistances to peptidyl transferase inhibitors by methylation of A2503 23S rRNA. Many cfr-like gene sequences in the databases code for unknown functions. This study confirms that a Cfr-like protein from a Peptoclostridium difficile (formerly Clostrid......The Cfr RNA methyltransferase causes multiple resistances to peptidyl transferase inhibitors by methylation of A2503 23S rRNA. Many cfr-like gene sequences in the databases code for unknown functions. This study confirms that a Cfr-like protein from a Peptoclostridium difficile (formerly...... Clostridium difficile) strain does function as a Cfr protein. The enzyme is expressed in Escherichia coli and shows elevated MICs for five classes of antibiotics. A primer extension stop indicates a modification at A2503 in 23S rRNA....
Full Text Available C. difficile is the most common cause of nosocomial diarrhea in North America and Europe. Genomes of individual strains of C. difficile are highly divergent. To determine how divergent strains respond to environmental changes, the transcriptomes of two historic and two recently isolated hypervirulent strains were analyzed following nutrient shift and osmotic shock. Illumina based RNA-seq was used to sequence these transcriptomes. Our results reveal that although C. difficile strains contain a large number of shared and strain specific genes, the majority of the differentially expressed genes were core genes. We also detected a number of transcriptionally active regions that were not part of the primary genome annotation. Some of these are likely to be small regulatory RNAs.
Comparison of primary predictive models to study the growth of Listeria monocytogenes at low temperatures in liquid cultures and selection of fastest growing ribotypes in meat and turkey product slurries.
Pal, Amit; Labuza, Theodore P; Diez-Gonzalez, Francisco
This study compared the performance of four primary mathematical models to study the growth kinetics of Listeria monocytogenes ribotypes grown at low temperature so as to identify the best predictive model. The parameters of the best-fitting model were used to select the fastest growing strains with the shortest lag time and greatest growth rate. Nineteen food, human and animal L. monocytogenes isolates with distinct ribotype were grown at 4, 8, and 12 degrees C in tryptic soy broth and slurries prepared from cooked uncured sliced turkey breasts (with or without potassium lactate and sodium diacetate, PL/SD) and cooked cured frankfurters (with or without PL/SD). Separate regressions were performed on semi-logarithm growth curves to fit linear (based on Monod) and non-linear (Gompertz, Baranyi-Roberts, and Logistic) equations and performance of each model was evaluated using an F-test. No significant differences were found in the performance of linear and non-linear models, but the Baranyi model had the best fit for most growth curves. The maximum growth rate (MGR) of Listeria strains increased with the temperature. Similarly MGR was found significantly greater when no antimicrobials were present in the formulation of turkey or frankfurter products. The variability in lag times and MGRs in all media as determined by the Baranyi model was not consistent among strains. No single strain consistently had the fastest growth (shortest lag time, fastest MGR, or shortest time to increase 100-fold), but nine strains were identified as fastest growing strains under most growth conditions. The lack of association between serotype and fastest strain was also observed in the slurry media study. The fastest growing strains resulting from this study can be recommended for future use in L. monocytogenes challenge studies in delicatessen meat and poultry food matrices, so as to develop conservative pathogen growth predictions.
Full Text Available Clostridium difficile, a major cause of nosocomial diarrhea and pseudomembranous colitis, still poses serious health-care challenges. The expression of its two main virulence factors, TcdA and TcdB, is reportedly repressed by cysteine, but molecular mechanism remains unclear. The cysteine desulfidase CdsB affects the virulence and infection progresses of some bacteria. The C. difficile strain 630 genome encodes a homolog of CdsB, and in the present study, we analyzed its role in C. difficile 630Δerm by constructing an isogenic ClosTron-based cdsB mutant. When C. difficile was cultured in TY broth supplemented with cysteine, the cdsB gene was rapidly induced during the exponential growth phase. The inactivation of cdsB not only affected the resistance of C. difficile to cysteine, but also altered the expression levels of intracellular cysteine-degrading enzymes and the production of hydrogen sulfide. This suggests that C. difficile CdsB is a major inducible cysteine-degrading enzyme. The inactivation of the cdsB gene in C. difficile also removed the cysteine-dependent repression of toxin production, but failed to remove the Na2S-dependent repression, which supports that the cysteine-dependent repression of toxin production is probably attributable to the accumulation of cysteine by-products. We also mapped a δ54 (SigL-dependent promoter upstream from the cdsB gene, and cdsB expression was not induced in response to cysteine in the cdsR::ermB or sigL::ermB strain. Using a reporter gene fusion analysis, we identified the necessary promoter sequence for cysteine-dependent cdsB expression. Taken together, these results indicate that CdsB is a key inducible cysteine desulfidase in C. difficile which is regulated by δ54 and CdsR in response to cysteine and that cysteine-dependent regulation of toxin production is closely associated with cysteine degradation.
Full Text Available Clostridium difficile colitis and cytomegalovirus colitis coinfection has been documented in immunocompromised patients. However, this kind of coinfection has rarely been reported in immunocompetent patients. We present a 90-year-old, critically ill, immunocompetent patient, who had a C. difficile and cytomegalovirus colitis coinfection. Although the common risk factors of both types of colitis are well known, clinical physicians still need to be alert to this coinfection because severe complications of CMV colitis have been reported previously. Physicians should be more aggressive in the management of elderly immunocompetent patients with refractory symptoms of colitis.
Fecal microbiota therapy is increasingly being used to treat patients with Clostridium difficile infection. This health technology assessment primarily evaluated the effectiveness and cost-effectiveness of fecal microbiota therapy compared with the usual treatment (antibiotic therapy). We performed a literature search using Ovid MEDLINE, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, CRD Health Technology Assessment Database, Cochrane Central Register of Controlled Trials, and NHS Economic Evaluation Database. For the economic review, we applied economic filters to these search results. We also searched the websites of agencies for other health technology assessments. We conducted a meta-analysis to analyze effectiveness. The quality of the body of evidence for each outcome was examined according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. Using a step-wise, structural methodology, we determined the overall quality to be high, moderate, low, or very low. We used a survey to examine physicians' perception of patients' lived experience, and a modified grounded theory method to analyze information from the survey. For the review of clinical effectiveness, 16 of 1,173 citations met the inclusion criteria. A meta-analysis of two randomized controlled trials found that fecal microbiota therapy significantly improved diarrhea associated with recurrent C. difficile infection versus treatment with vancomycin (relative risk 3.24, 95% confidence interval [CI] 1.85-5.68) (GRADE: moderate). While fecal microbiota therapy is not associated with a significant decrease in mortality compared with antibiotic therapy (relative risk 0.69, 95% CI 0.14-3.39) (GRADE: low), it is associated with a significant increase in adverse events (e.g., short-term diarrhea, relative risk 30.76, 95% CI 4.46-212.44; abdominal cramping, relative risk 14.81, 95% CI 2.07-105.97) (GRADE: low). For
Morley, Alexander A.
Digital PCR for quantification of a target of interest has been independently developed several times, being described in 1990 and 1991 using the term “limiting dilution PCR” and in 1999 using the term “digital PCR”. It came into use in the decade following its first development but its use was cut short by the description of real-time PCR in 1996. However digital PCR has now had a renaissance due to the recent development of new instruments and chemistry which have made it a much simpler and...
Skoutelis, Athanasios; Pefanis, Angelos; Tsiodras, Sotirios; Sipsas, Nikolaos V; Lelekis, Moyssis; Lazanas, Marios C; Gargalianos, Panagiotis; Dalekos, George N; Roilides, Emmanuel; Samonis, George; Maltezos, Efstratios; Hatzigeorgiou, Dimitrios; Lada, Malvina; Metallidis, Symeon; Stoupis, Athena; Chrysos, Georgios; Karnesis, Lazaros; Symbardi, Styliani; Loupa, Chariclia V; Giamarellou, Helen; Kioumis, Ioannis; Sambatakou, Helen; Tsianos, Epameinondas; Kotsopoulou, Maria; Georgopali, Areti; Liakou, Klairi; Perlorentzou, Stavroula; Levidiotou, Stamatina; Giotsa-Toutouza, Marina; Tsorlini-Christoforidou, Helen; Karaiskos, Ilias; Kouppari, Georgia; Trikka-Graphakos, Eleftheria; Ntrivala, Maria-Anna; Themeli-Digalaki, Kate; Pangalis, Anastasia; Kachrimanidou, Melina; Martsoukou, Maria; Karapsias, Stergios; Panopoulou, Maria; Maraki, Sofia; Orfanou, Anagnostina; Petinaki, Efthymia; Orfanidou, Maria; Baka, Vasiliki; Stylianakis, Antonios; Spiliopoulou, Iris; Smilakou, Stavroula; Zerva, Loukia; Vogiatzakis, Evangelos; Belesiotou, Eleni; Gogos, Charalambos A
The correlation of Clostridium difficile infection (CDI) with in-hospital morbidity is important in hospital settings where broad-spectrum antimicrobial agents are routinely used, such as in Greece. The C. DEFINE study aimed to assess point-prevalence of CDI in Greece during two study periods in 2013. There were two study periods consisting of a single day in March and another in October 2013. Stool samples from all patients hospitalized outside the ICU aged ≥18 years old with diarrhea on each day in 21 and 25 hospitals, respectively, were tested for CDI. Samples were tested for the presence of glutamate dehydrogenase antigen (GDH) and toxins A/B of C. difficile; samples positive for GDH and negative for toxins were further tested by culture and PCR for the presence of toxin genes. An analysis was performed to identify potential risk factors for CDI among patients with diarrhea. 5,536 and 6,523 patients were screened during the first and second study periods, respectively. The respective point-prevalence of CDI in all patients was 5.6 and 3.9 per 10,000 patient bed-days whereas the proportion of CDI among patients with diarrhea was 17% and 14.3%. Logistic regression analysis revealed that solid tumor malignancy [odds ratio (OR) 2.69, 95% confidence interval (CI): 1.18-6.15, p = 0.019] and antimicrobial administration (OR 3.61, 95% CI: 1.03-12.76, p = 0.045) were independent risk factors for CDI development. Charlson's Comorbidity Index (CCI) >6 was also found as a risk factor of marginal statistical significance (OR 2.24, 95% CI: 0.98-5.10). Median time to CDI from hospital admission was shorter with the presence of solid tumor malignancy (3 vs 5 days; p = 0.002) and of CCI >6 (4 vs 6 days, p = 0.009). The point-prevalence of CDI in Greek hospitals was consistent among cases of diarrhea over a 6-month period. Major risk factors were antimicrobial use, solid tumor malignancy and a CCI score >6.
Eroboghene H Otete
Full Text Available INTRODUCTION: Mathematical modelling of Clostridium difficile infection dynamics could contribute to the optimisation of strategies for its prevention and control. The objective of this systematic review was to summarise the available literature specifically identifying the quantitative parameters required for a compartmental mathematical model of Clostridium difficile transmission. METHODS: Six electronic healthcare databases were searched and all screening, data extraction and study quality assessments were undertaken in duplicate. Results were synthesised using a narrative approach. RESULTS: Fifty-four studies met the inclusion criteria. Reproduction numbers for hospital based epidemics were described in two studies with a range from 0.55 to 7. Two studies provided consistent data on incubation periods. For 62% of cases, symptoms occurred in less than 4 weeks (3-28 days after infection. Evidence on contact patterns was identified in four studies but with limited data reported for populating a mathematical model. Two studies, including one without clinically apparent donor-recipient pairs, provided information on serial intervals for household or ward contacts, showing transmission intervals of <1 week in ward based contacts compared to up to 2 months for household contacts. Eight studies reported recovery rates of between 75%-100% for patients who had been treated with either metronidazole or vancomycin. Forty-nine studies gave recurrence rates of between 3% and 49% but were limited by varying definitions of recurrence. No study was found which specifically reported force of infection or net reproduction numbers. CONCLUSIONS: There is currently scant literature overtly citing estimates of the parameters required to inform the quantitative modelling of Clostridium difficile transmission. Further high quality studies to investigate transmission parameters are required, including through review of published epidemiological studies where these
Endres, Bradley T; Bassères, Eugénie; Memariani, Ali; Chang, Long; Alam, M Jahangir; Vickers, Richard J; Kakadiaris, Ioannis A; Garey, Kevin W
Clostridium difficile is a significant cause of nosocomial-acquired infection that results in severe diarrhea and can lead to mortality. Treatment options for C. difficile infection (CDI) are limited, however, new antibiotics are being developed. Current methods for determining efficacy of experimental antibiotics on C. difficile involve antibiotic killing rates and do not give insight into the drug's pharmacologic effects. Considering this, we hypothesized that by using scanning electron microscopy (SEM) in tandem to drug killing curves, we would be able to determine efficacy and visualize the phenotypic response to drug treatment. To test this hypothesis, supraMIC kill curves were conducted using vancomycin, metronidazole, fidaxomicin, and ridinilazole. Following collection, cells were either plated or imaged using a scanning electron microscope (SEM). Consistent with previous reports, we found that the tested antibiotics had significant bactericidal activity at supraMIC concentrations. By SEM imaging and using a semi-automatic pipeline for image analysis, we were able to determine that vancomycin and to a lesser extent fidaxomicin and ridinilazole significantly affected the cell wall, whereas metronidazole, fidaxomicin, and ridinilazole had significant effects on cell length suggesting a metabolic effect. While the phenotypic response to drug treatment has not been documented previously in this manner, the results observed are consistent with the drug's mechanism of action. These techniques demonstrate the versatility and reliability of imaging and measurements that could be applied to other experimental compounds. We believe the strategies laid out here are vital for characterizing new antibiotics in development for treating CDI. Copyright © 2016 Elsevier Ltd. All rights reserved.
Full Text Available Clostridium difficile es un bacilo grampositivo que durante los últimos años se ha convertido en una de las principales infecciones gastrointestinales adquiridas en el hospital para el ser humano. Recientemente su incidencia se ha incrementado, implicando cepas más virulentas que afectan nuevos grupos de pacientes que antes no se tenían contemplados, generado cambios en la presentación clínica y en la respuesta al tratamiento que influyen en el pronóstico de la enfermedad. El diagnóstico precoz y la estratificación de la enfermedad con base en la gravedad de la infección por C. difficile es fundamental para el manejo terapéutico y para la implementación de medidas de contención. Sin embargo, la velocidad con la que se desarrollan nuevas cepas con mayor patogenicidad se encuentra por encima de aquella con la que se desarrollan nuevos fármacos, siendo necesaria la validación de otras opciones terapéuticas. En el presente artículo revisamos los aspectos epidemiológicos, fisiopatológicos, diagnósticos y terapéuticos de la infección por C. difficile desde su primer aislamiento hasta la fecha, con el objetivo de contribuir en la preparación de médicos generales y especialistas para que proporcionen atención oportuna y de calidad a quienes la padezcan.
Gray, Mikel; Omar, Amin; Buziak, Brenton
The purpose of this study was to compare contamination of the immediate environment with Clostridium difficile spores and vegetative cells from 2 stool management systems over a period of 30 days in a controlled laboratory setting. In vitro, comparison trial. Two stool management systems were compared over a 30-day period in a controlled laboratory setting. Sixteen systems were filled with sterile loose canine stool inoculated with 10 colony-forming units (CFUs) per milliliter of C difficile; specially prepared culture media were used to detect C difficile contamination on various surfaces of the device and in the immediate environment. Containment bags were changed daily and devices were refilled with inoculated stool to more closely imitate use in the clinical setting. A dichotomous outcome variable (growth vs no growth) was used to analyze contamination on a daily basis via the generalized estimating equation; devices were also compared on days 3, 10, 20, and 30 by measuring CFUs per device surface. Logistic regression analysis was used to analyze growth over time. When observations showed no growth, the Cochran-Mantel Haenszel test was used to compare study devices. Analysis revealed that 20.8% of anterior surfaces of the collection bags for device 1 were contaminated versus 83.9% of collection bags for device 2 (P < .001). Comparison of the tubing/hub interface resulted in similar findings; 20.8% of device 1 group were contaminated versus 86.3% of device 2 group (P < .001). Analysis of an absorbent pad placed under the device during daily changes found that 0.5% of device 1 were contaminated versus 38.1% of pads placed under device 2 (P < .001). Findings from this in vitro study show that stool management systems can limit or prevent environmental contamination of C difficile. Results also reveal significant differences in the 2 systems tested; we hypothesize that these differences are attributable to the interface between the tubing and collection bag, the
Franco Arenaz, María
Identificar els possibles factors de risc de mortalitat en els pacients amb un primer episodi de diarrea associada a Clostridium difficile (DACD) mitjançant un estudi observacional retrospectiu. Després d'una anàlisi uni i multivariant amb les següents variables (sexe, edat, índex de Charlson, número d'antibiòtics previs i la seva retirada, ús de corticoids, inhibidors de la bomba de protons o antihistamínics antiH2, antiàcids, procedència de residència geriàtrica, dies de tractament per a la...
Spinler, Jennifer K.; Ross, Caná L.; Savidge, Tor C.
With the end of the golden era of antibiotic discovery, the emergence of a new post-antibiotic age threatens to thrust global health and modern medicine back to the pre-antibiotic era. Antibiotic overuse has resulted in the natural evolution and selection of multi-drug resistant bacteria. One major public health threat, Clostridium difficile, is now the single leading cause of hospital-acquired bacterial infections and is by far the most deadly enteric pathogen for the U.S. population. Due to...
UV-visible marker confirms that environmental persistence of Clostridium difficile spores in toilets of patients with C. difficile-associated diarrhea is associated with lack of compliance with cleaning protocol.
Full Text Available Abstract Background An ultraviolet visible marker (UVM was used to assess the cleaning compliance of housekeeping staff for toilets in a tertiary healthcare setting. Methods The UVM was applied to the toilets of patients who were on isolation precautions due to Clostridium difficile-associated diarrhea (CDAD as well as for patients who were not on isolation precautions. Cleaning was visually scored using a numeric system where 0, 1, 2, and 3 represented; no, light, moderate or heavy residual UVM. Rodac plates containing CDMN selective agar were used to test for the presence of C. difficile on the surfaces of patient's toilets. Results Despite twice daily cleaning for the toilets of patients who were on CDAD isolation precautions, the average cleaning score was 1.23 whereas the average cleaning score for toilets of patients not on isolation precautions was 0.9. Even with optimal cleaning (UVM score of 0 C. difficile was detected from 33% of the samples taken from toilets of patients with CDAD (4% detection in toilet samples from patients who had diarrhea not due to CDAD. Conclusion Our data demonstrated the value of UVM for monitoring the compliance of housekeeping staff with the facility's toilet cleaning protocol. In addition to providing good physical cleaning action, agents with some sporicidal activity against C. difficile may be needed to effectively reduce the environmental reservoir.
Turgeon, David K; Novicki, Thomas J; Quick, John; Carlson, LaDonna; Miller, Pat; Ulness, Bruce; Cent, Anne; Ashley, Rhoda; Larson, Ann; Coyle, Marie; Limaye, Ajit P; Cookson, Brad T; Fritsche, Thomas R
Clostridium difficile is one of the most frequent causes of nosocomial gastrointestinal disease. Risk factors include prior antibiotic therapy, bowel surgery, and the immunocompromised state. Direct fecal analysis for C. difficile toxin B by tissue culture cytotoxin B assay (CBA), while only 60 to 85% sensitive overall, is a common laboratory method. We have used 1,003 consecutive, nonduplicate fecal samples to compare six commercially available immunoassays (IA) for C. difficile detection with CBA: Prima System Clostridium difficile Tox A and VIDAS Clostridium difficile Tox A II, which detect C. difficile toxin A; Premier Cytoclone A/B and Techlab Clostridium difficile Tox A/B, which detect toxins A and B; and ImmunoCard Clostridium difficile and Triage Micro C. difficile panels, which detect toxin A and a species-specific antigen. For all tests, Triage antigen was most sensitive (89.1%; negative predictive value [NPV] = 98.7%) while ImmunoCard was most specific (99.7%; positive predictive value [PPV] = 95.0%). For toxin tests only, Prima System had the highest sensitivity (82.2%; NPV = 98.0%) while ImmunoCard had the highest specificity (99.7%; PPV = 95.0%). Hematopoietic stem cell transplant (HSCT) patients contributed 44.7% of all samples tested, and no significant differences in sensitivity or specificity were noted between HSCT and non-HSCT patients. IAs, while not as sensitive as direct fecal CBA, produce reasonable predictive values, especially when both antigen and toxin are detected. They also offer significant advantages over CBA in terms of turnaround time and ease of use.
Erikstrup, Lise Tornvig; Aarup, Mie; Hagemann-Madsen, Rikke
OBJECTIVE: Clostridium difficile is a major cause of nosocomial infectious diarrhoea. Treatment of C. difficile infection (CDI) depends on disease severity. A combination of vancomycin and metronidazole is often recommended in severe cases. The aim of this study was to examine, in a murine model....... difficile toxins. RESULTS: None of the mice in the vancomycin-treated group died during the treatment phase compared to a mortality of 17%, 33% and 55% in the combination, metronidazole and infected control group, respectively. Mice treated with vancomycin alone or in combination with metronidazole...
Trubiano, J A; Cheng, A C; Korman, T M; Roder, C; Campbell, A; May, M L A; Blyth, C C; Ferguson, J K; Blackmore, T K; Riley, T V; Athan, E
The incidence of Clostridium difficile infection (CDI) continues to rise, whilst treatment remains problematic due to recurrent, refractory and potentially severe nature of disease. The treatment of C. difficile is a challenge for community and hospital-based clinicians. With the advent of an expanding therapeutic arsenal against C. difficile since the last published Australasian guidelines, an update on CDI treatment recommendations for Australasian clinicians was required. On behalf of the Australasian Society of Infectious Diseases, we present the updated guidelines for the management of CDI in adults and children. © 2016 Royal Australasian College of Physicians.
Prediction of severe clinical outcomes in Clostridium difficile infection (CDI) is important to inform management decisions for optimum patient care. Currently, treatment recommendations for CDI vary based on disease severity but validated methods to predict severe disease are lacking. The aim of the study was to derive and validate a clinical prediction tool for severe outcomes in CDI.
Diff colitis. These can serve as focal points for intervention such as improving nutrition (for weight loss), treating infection, and optimizing...for Clostridium difficile-associated disease in long-term care. Geriatr Nurs 2007;28(3):171-81; quiz 182. [doi: 10.1016/j.gerinurse.2007.02.003
L.I. Chernyshova; A.M. Gilfanova
The article highlighted the dependence of the incidence of antibiotic-associated diarrhea in children on risk factors, age, prescribed antibiotics and probiotic preparations; clinical features of its course in children with respiratory infections were shown, Clostridium difficile value was clarified in the etiological structure of diarrhea, associated with antibiotics intake.
Oppfeldt, Asser Mathiassen; Dahlerup, Jens F; Christensen, Lisbet A
Faecal microbiota transplantation (FMT) is increasingly being used to treat refractory and recurring Clostridium difficile infection (CDI). Although FMT appears to be safe and highly effective in patients with a preserved colon and immunocompetence, its use in patients with inflammatory bowel...
Nuenen, M.H.M.C. van; Meyer, P.D.; Venema, K.
The influence of inulins with different average degree of polymerization (ranging from 3 to 25) on the metabolic activity of the human colonic microbiota with or without the addition of Clostridium difficile was investigated in vitro. The in vitro system used was a dynamic, computer-controlled model
Full Text Available Abstract Background The role of asymptomatic carriers of toxigenic Clostridium difficile (TCD in nosocomial cross-transmission remains debatable. Moreover, its relevance in the elderly has been sparsely studied. Objectives To assess asymptomatic TCD carriage in an acute care geriatric population. Methods We performed a prospective cohort study at the 296-bed geriatric hospital of the Geneva University Hospitals. We consecutively recruited all patients admitted to two 15-bed acute-care wards. Patients with C. difficile infection (CDI or diarrhoea at admission were excluded. First bowel movement after admission and every two weeks thereafter were sampled. C. difficile toxin B gene was identified using real-time polymerase chain-reaction (BD MAXTMCdiff. Asymptomatic TCD carriage was defined by the presence of the C. difficile toxin B gene without diarrhoea. Results A total of 102 patients were admitted between March and June 2015. Two patients were excluded. Among the 100 patients included in the study, 63 were hospitalized and 1 had CDI in the previous year, and 36 were exposed to systemic antibiotics within 90 days prior to admission. Overall, 199 stool samples were collected (median 2 per patient, IQR 1-3. Asymptomatic TCD carriage was identified in two patients (2 %. Conclusions We found a low prevalence of asymptomatic TCD carriage in a geriatric population frequently exposed to antibiotics and healthcare. Our findings suggest that asymptomatic TCD carriage might contribute only marginally to nosocomial TCD cross-transmission in our and similar healthcare settings.
Kelly, Brendan J; Tebas, Pablo
A substantial proportion of Clostridium difficile infection (CDI) cases recur after completion of antibiotic therapy, and antibiotic cure rates diminish with each recurrence of CDI. Fecal microbiota transplantation (FMT) is an effective therapy for recurrent FMT, which otherwise requires prolonged or indefinite antibiotic treatment. FMT is performed by introducing the fecal microbial community obtained from a healthy donor or pool of donors into the stomach, small intestine, or colon of a patient with CDI. Multiple clinical trials support the usefulness of FMT in treating recurrent CDI, and CDI treatment guidelines now include consideration of FMT at the third CDI recurrence. However, there remain challenges to incorporating FMT into clinical practice. First, methods of fecal bacterial community processing vary, as do methods of FMT administration. Second, the optimal dosing strategy and expected benefit of FMT for refractory CDI, particularly for severe and severe complicated cases, are uncertain. Third, the US Food and Drug Administration (FDA) considers FMT an investigational treatment. Fourth, insurance reimbursement for FMT usually falls short of FMT administration costs. In the setting of rising C difficile incidence and growing evidence for FMT efficacy, the demand for FMT has increased. However, uncertainty surrounding optimal FMT preparation and administration methods, FDA oversight, and insurance reimbursement presently limits the clinical practice of FMT. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
Goyal, Abhinav; Chatterjee, Kshitij; Yadlapati, Sujani; Rangaswami, Janani
To assess the impact of end stage kidney disease (ESKD) on the outcomes of Clostridium difficile infection (CDI), including complications of infection, length of hospital stay, overall mortality, and healthcare burden. The National Inpatient Sample (NIS) database created by the Agency of Healthcare Research and Quality (AHRQ) was used, covering the years 2009 through 2013. Manufacturer-provided sampling weights were used to produce national estimates. All-cause unadjusted in-hospital mortality was significantly higher for patients with CDI and ESKD than for patients without ESKD (11.6% vs. 7.7%, paverage cost of hospitalization for patients with CDI and ESKD was also significantly higher compared to the non-ESKD group (USD $35 588 vs. $23 505, in terms of the 2013 value of the USD, pend stage kidney disease in hospitalized patients with Clostridium difficile infection is associated with higher mortality, a longer length of stay, and a higher cost of hospitalization. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Batista, R; Kapel, N; Megerlin, F; Chaumeil, J-C; Barbut, F; Bourlioux, P; Chast, F
The fecal microbiota transplantation consists in introducing a preparation constituted by a dilution of stools of a healthy donor in the digestive tract of a patient recipient, to restore his intestinal physiological balance. This therapeutic approach was the subject of numerous studies showing its efficiency in the treatment of the recurrent infections with Clostridium difficile. The fecal microbiota transplantation has now a high level of clinical evidence, which explains that it appears in various international recommendations. In France, the fecal microbiota transplantation responds to the definition of a medication and can be executed as a pharmaceutical preparation or as an experimental drug for clinical trials under the responsibility of a hospital pharmacy. The objective of this paper is to propose a definition of a framework and to describe the methods of preparation of the fecal microbiota transplantation in the treatment of the recurrent infections with C. difficile and the interactions to consider for hospital pharmacies that do not have technical means to operate this technique. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Clostridium difficile is the most common cause of nosocomial infectious diarrhea in adults, with recent reports of increased severity and case fatality. Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are increasingly recognized and treatable complications of severe illness in medical patients, and are independent predictors of mortality. Patients with severe Clostridium difficile infection (CDI) are at increased risk for IAH and ACS. However, ACS has been only rarely described in this population. We report a case of a 61 year-old morbidly obese, chronically ill, ventilator dependent patient, who developed fulminant CDI, including progressive colonic distension, acute renal failure and intra-abdominal fluid sequestration. Her clinical course worsened abruptly, with new shock, worsening hypoxic respiratory failure, increased peak airway pressures and reduced tidal volumes. Intra-abdominal pressure was 30 mm Hg. The patient was not considered a surgical candidate, was refractory to escalating non-surgical support, and died following withdrawal of life support. Although patients with fulminant CDI share many risk factors for IAH and ACS, these conditions were rarely reported in this population and are likely under recognized, as was the case with the present patient. Increased vigilance for IAH is needed in this at-risk population.
Jan K. Adamski
Full Text Available Development of the extreme form of hypothyroidism defined as myxedema is very rare. Acute symptoms and their management have been described in detail previously. However, not much attention has been devoted to therapeutic challenges that are faced in the recovery phase of the treatment, especially pertaining to the gastrointestinal system. The link between myxedema and the appearance of severe Clostridium difficile infection (CDI has not been established so far. A 61-year-old woman with no significant medical record was admitted to hospital because of infected heel pressure and thyroid dysfunction. A week later, due to hypothermia, hypotension, and unconsciousness, she was transferred to the intensive care unit. The clinical picture and the results of laboratory tests confirmed diagnosis of myxedema. After the introduction of resuscitative measures and hormonal substitution, patient’s condition stabilized within 10 days. Due to concomitant sepsis, initially piperacillin/tazobactam and later cefuroxime were administered. After 20 days of antibiotic therapy, the patient developed CDI that was resistant to the routine mode of treatment. The clinical recovery was achieved only after a fecal microbiota transplantation procedure. The function of the digestive tract in myxedema is disturbed by gastric achlorydia and reduced peristalsis, which in turn can predispose the small intestine to overgrowth of bacteria. The use of antibiotics can additionally decrease the intestinal bacterial diversity, favoring the overgrowth of Clostridium difficile. The authors conclude that myxedema may increase the likelihood of a treatment-resistant form of CDI that requires the implementation of fecal microbiota transplantation.
Ho, Jeffery; Dai, Rudin Z.W.; Kwong, Thomas N.Y.; Wang, Xiansong; Zhang, Lin; Ip, Margaret; Chan, Raphael; Hawkey, Peter M.K.; Lam, Kelvin L.Y.; Wong, Martin C.S.; Tse, Gary; Chan, Matthew T.V.; Chan, Francis K.L.; Yu, Jun; Ng, Siew C.; Lee, Nelson; Wu, Justin C.Y.; Sung, Joseph J.Y.
Cross-sectional studies suggest an increasing trend in incidence and relatively low recurrence rates of Clostridium difficile infections in Asia than in Europe and North America. The temporal trend of C. difficile infection in Asia is not completely understood. We conducted a territory-wide population-based observational study to investigate the burden and clinical outcomes in Hong Kong, China, over a 9-year period. A total of 15,753 cases were identified, including 14,402 (91.4%) healthcare-associated cases and 817 (5.1%) community-associated cases. After adjustment for diagnostic test, we found that incidence increased from 15.41 cases/100,000 persons in 2006 to 36.31 cases/100,000 persons in 2014, an annual increase of 26%. This increase was associated with elderly patients, for whom incidence increased 3-fold over the period. Recurrence at 60 days increased from 5.7% in 2006 to 9.1% in 2014 (p<0.001). Our data suggest the need for further surveillance, especially in Asia, which contains ≈60% of the world’s population. PMID:28930010
Goldenberg, Joshua Z; Yap, Christina; Lytvyn, Lyubov; Lo, Calvin Ka-Fung; Beardsley, Jennifer; Mertz, Dominik; Johnston, Bradley C
Antibiotics can disturb gastrointestinal microbiota which may lead to reduced resistance to pathogens such as Clostridium difficile (C. difficile). Probiotics are live microbial preparations that, when administered in adequate amounts, may confer a health benefit to the host, and are a potential C. difficile prevention strategy. Recent clinical practice guidelines do not recommend probiotic prophylaxis, even though probiotics have the highest quality evidence among cited prophylactic therapies. To assess the efficacy and safety of probiotics for preventing C.difficile-associated diarrhea (CDAD) in adults and children. We searched PubMed, EMBASE, CENTRAL, and the Cochrane IBD Group Specialized Register from inception to 21 March 2017. Additionally, we conducted an extensive grey literature search. Randomized controlled (placebo, alternative prophylaxis, or no treatment control) trials investigating probiotics (any strain, any dose) for prevention of CDAD, or C. difficile infection were considered for inclusion. Two authors (independently and in duplicate) extracted data and assessed risk of bias. The primary outcome was the incidence of CDAD. Secondary outcomes included detection of C. difficile infection in stool, adverse events, antibiotic-associated diarrhea (AAD) and length of hospital stay. Dichotomous outcomes (e.g. incidence of CDAD) were pooled using a random-effects model to calculate the risk ratio (RR) and corresponding 95% confidence interval (95% CI). We calculated the number needed to treat for an additional beneficial outcome (NNTB) where appropriate. Continuous outcomes (e.g. length of hospital stay) were pooled using a random-effects model to calculate the mean difference and corresponding 95% CI. Sensitivity analyses were conducted to explore the impact of missing data on efficacy and safety outcomes. For the sensitivity analyses, we assumed that the event rate for those participants in the control group who had missing data was the same as the
R. A. Cardoso
Full Text Available This study investigated the ability of Clostridium difficile toxin B, isolated from the VPI 10463 strain, to induce fever and neutrophilia in rats. Intravenous injection of toxin B (0.005–0.5 μg/kg evoked a dose-dependent increase in body temperature. The febrile response to 0.5 μg/kg of the toxin started in 2.5 h, peaked at 5 h, and subsided fully within 24 h. Toxin B also induced a dosedependent neutrophilia. Pretreatment with indomethacin (2 mg/kg, i.p. did not affect the neutrophilia induced by toxin B, but significantly reduced the febrile response measured 4 to 8 h after toxin B injection. Dexamethasone (0.5 mg/ kg also markedly diminished the febrile response induced by toxin B. These results show that Clostridium difficile toxin B induced a febrile response susceptible to inhibition by dexamethasone and indomethacin. Furthermore, they suggest that prostaglandins are not involved in the neutrophilia caused by this toxin.
Full Text Available Clostridium difficile is an opportunistic pathogen inhabiting the human gut, often being the aetiological agent of infections after a microbiota dysbiosis following, for example, an antibiotic treatment. C. difficile infections (CDI constitute a growing health problem with increasing rates of morbidity and mortality at groups of risk, such as elderly and hospitalized patients, but also in populations traditionally considered low-risk. This could be related to the occurrence of virulent strains which, among other factors, have high-level of resistance to fluoroquinolones, more efficient sporulation and markedly high toxin production. Several novel intervention strategies against CDI are currently under study, such as the use of probiotics to counteract the growth and/or toxigenic activity of C. difficile.In this work, we have analysed the capability of twenty Bifidobacterium and Lactobacillus strains, from human intestinal origin, to counteract the toxic effect of C. difficile LMG21717 upon the human intestinal epithelial cell line HT29. For this purpose, we incubated the bacteria together with toxigenic supernatants obtained from C. difficile. After this co-incubation new supernatants were collected in order to quantify the remnant A and B toxins, as well as to determine their residual toxic effect upon HT29 monolayers. To this end, the real time cell analyser (RTCA model, recently developed in our group to monitor C. difficile toxic effect, was used. Results obtained showed that strains of Bifidobacterium longum and Bifidobacterium breve were able to reduce the toxic effect of the pathogen upon HT29, the RTCA normalized cell-index values being inversely correlated with the amount of remnant toxin in the supernatant. The strain B. longum IPLA20022 showed the highest ability to counteract the cytotoxic effect of C. difficile acting directly against the toxin, also having the highest capability for removing the toxins from the clostridial
Mac Aogáin, Micheál; Kilkenny, Shauna; Walsh, Claire; Lindsay, Sinéad; Moloney, Geraldine; Morris, Trefor; Jones, Sophie; Rogers, Thomas R
The aim of this study was to determine whether alternative resistance mechanisms, other than mutation in the quinolone resistance-determining region (QRDR) of DNA gyrase, could confer fluoroquinolone resistance in Clostridium difficile. An in vitro-generated C. difficile mutant exhibiting increased fluoroquinolone resistance was isolated through antibiotic selection on ciprofloxacin. The QRDR of this mutant was investigated by chain-termination sequencing and was found to be devoid of mutation. To determine the nature of the non-QRDR resistance mechanism in this strain, the genomes of the mutant and wild-type strains were sequenced. The gyrBA region from a collection of clinical isolates exhibiting variable fluoroquinolone resistance levels was also sequenced and was compared with that present in 918 publicly available C. difficile genomic data sets. Whole-genome sequence analysis of the fluoroquinolone-resistant mutant revealed a single non-synonymous substitution (Ala384Asp) at the predicted primary dimer interface of GyrA, far beyond the classically defined QRDR. This novel mutation caused increased resistance to ciprofloxacin, ofloxacin, levofloxacin and moxifloxacin while conferring hypersusceptibility to novobiocin. Several novel extra-QRDR polymorphisms in C. difficile DNA gyrase were identified among clinical isolates, whilst observed fluoroquinolone resistance in strains devoid of gyrBA mutations confirmed the existence of DNA gyrase-independent resistance mechanisms in this species. In conclusion, we report the first non-QRDR mutation to confer fluoroquinolone resistance in C. difficile. Although the Ala384Asp substitution was not detected in clinical isolates, this study revealed a diversity of alternative extra-QRDR polymorphisms in DNA gyrase whose association with fluoroquinolone resistance warrants further investigation. Copyright © 2015 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.
Anderson, Chelsea E; Haulena, Martin; Zabek, Erin; Habing, Gregory; Raverty, Stephen
Between 1998 and 2008, 15 cases of segmental to diffuse hemorrhagic to necrohemorrhagic enterocolitis were diagnosed in neonatal and weaned juvenile harbor seals (Phoca vitulina) presented from the Vancouver Aquarium Marine Mammal Rescue Centre for rehabilitation. Based on a combination of gross pathology, histopathology, bacterial isolation, and toxin testing, Clostridium difficile enterocolitis was diagnosed. Most pups were anorexic or inappetant and died acutely with few other premonitory signs. Due to ongoing clinical concerns and possible emergence of this pathogen at the facility, efforts to better characterize the disease and understand the epidemiology of C. difficile was initiated in 95 harbor seal pups presented for rehabilitation in a single stranding season. Fecal samples were collected on admission, following completion of antibiotic treatment, and also prerelease or postmortem. All samples were collected fresh and submitted either directly or stored frozen. Fecal samples were inoculated into selective media for culture and screened by enzyme-linked immunosorbant assay (ELISA) for C. difficile toxins A, B, or both. Results of the 95 seals in the study were as follows: on hospital admit 72 seals were sampled, 10 were culture positive, 12 were ELISA positive; following antibiotic therapy 46 seals were sampled noting three culture positive and nine ELISA positive; prior to release 58 seals were sampled noting zero culture positive and one ELISA positive; and on postmortem exam seven seals were sampled noting zero culture positive and two ELISA positive. Clostridium difficile was not deemed to be the cause of death in any of the animals. Although the exact mechanism of disease is unknown, this study suggests that C. difficile infection is not a significant cause of mortality and may be part of the normal flora in harbor seals undergoing rehabilitation. Morbidity and mortality from this bacterium can likely be minimized by judicious use of antibiotics
Full Text Available Methylation‐specific PCR (MSP is a simple, quick and cost‐effective method to analyze the DNA methylation status of virtually any group of CpG sites within a CpG island. The technique comprises two parts: (1 sodium bisulfite conversion of unmethylated cytosine's to uracil under conditions whereby methylated cytosines remains unchanged and (2 detection of the bisulfite induced sequence differences by PCR using specific primer sets for both unmethylated and methylated DNA. This review discusses the critical parameters of MSP and presents an overview of the available MSP variants and the (clinical applications.
Efficacy and Safety of, and Patient Satisfaction with, Colonoscopic-Administered Fecal Microbiota Transplantation in Relapsing and Refractory Community- and Hospital-Acquired Clostridium difficile Infection
Muhammad Ali Khan
Full Text Available OBJECTIVE: To report the efficacy and safety of, and patient satisfaction with, colonoscopic fecal microbiota transplantation (FMT for community- and hospital-acquired Clostridium difficile infection (CDI.
Boonma, Prapaporn; Spinler, Jennifer K; Venable, Susan F; Versalovic, James; Tumwasorn, Somying
Background Clostridium difficile is the main cause of hospital-acquired diarrhea and colitis known as C. difficile-associated disease (CDAD).With increased severity and failure of treatment in CDAD, new approaches for prevention and treatment, such as the use of probiotics, are needed. Since the pathogenesis of CDAD involves an inflammatory response with a massive influx of neutrophils recruited by interleukin (IL)-8, this study aimed to investigate the probiotic effects of Lactobacillus spp....
Cecília L. Costa
Full Text Available Clostridium difficile is the most important cause of nosocomial diarrhea, mainly associated with antibiotic use and immunodeficiency. Although, an increased incidence of community-acquired C. difficile infection (CA-CDI has been reported worldwide, this infection has been under-diagnosed in Latin America. This is the first report of a CA-CDI case in Latin America, in an HIV-positive patient with cancer.
Full Text Available Mayu Hikone,1 Yusuke Ainoda,1,2 Sayaka Tago,2 Takahiro Fujita,2 Yuji Hirai,2 Kaori Takeuchi,2 Kyoichi Totsuka31Department of Infectious Diseases, Tokyo Metropolitan Bokutoh General Hospital, 2Department of Infectious Diseases, Tokyo Women's Medical University, 3Department of Internal Medicine, Kitatama Hospital, Tokyo, JapanBackground: Clostridium difficile infection (CDI is a highly prevalent hospital-associated infection. Although most patients respond well to discontinuation of antibiotics, 20%–30% of patients relapse. To initiate early therapeutic measures, the risk factors for recurrent CDI must be identified, although very few Japanese studies have used standard surveillance definitions to identify these risk factors.Methods: We retrospectively reviewed the medical records of patients with health care facility-onset CDI between August 2011 and September 2013. Patients with diarrhea who were positive for Clostridium difficile (via an enzyme immunoassay were defined as having CDI. Clinical data (eg, demographics, comorbidities, medication, laboratory results, and clinical outcomes were evaluated, and multivariate analysis was used to identify risk factors that were associated with recurrent CDI.Results: Seventy-six health care facility-onset CDI cases were identified, with an incidence rate of 0.8 cases per 10,000 patient-days. Fourteen cases (18.4% were recurrent, with 13 patients having experienced a single recurrent episode and one patient having experienced three recurrent episodes. The 30-day and 90-day mortality rates were 7.9% and 14.5%, respectively. Multivariate analysis revealed that recurrent patients were more likely to have underlying malignant disease (odds ratio: 7.98; 95% confidence interval: 1.22–52.2; P=0.03 and a history of intensive care unit hospitalization (odds ratio: 49.9; 95% confidence interval: 1.01–2,470; P=0.049.Conclusion: Intensive care unit hospitalization and malignancy are risk factors for recurrent
Genetic variability within Fusarium solani specie as revealed by PCR-fingerprinting based on pcr markers Variabilidade genética em espécies de Fusarium solani revelada pela técnica de impressão genética baseada em marcadores PCR
Bereneuza Tavares Ramos Valente Brasileiro
Full Text Available Fusarium solani fungus (teleomorph Haematonectria haematococca is of relevance for agriculture, producing a disease that causes significant losses for many cultivars. Moreover, F. solani is an opportunistic pathogen to animals and humans. The complexity associated to its correct identification by traditional methods justifies the efforts of using molecular markers for isolates characterization. In this work, three PCR-based methods (one PCR-ribotyping and two PCR-fingerprinting were used to investigate the molecular variability of eighteen F. solani isolates from four Brazilian States, collected from different substrates. Genetic analysis revealed the intraspecific variability within the F. solani isolates, without any correlation to their geographical origin and substrate. Its polymorphism was observed even in the very conserved sequence of rDNA locus, and the SPAR marker (GTG5 showed the highest polymorphism. Together, those results may contribute to understand the relation between fungal genetic variability and cultivars resistance phenotypes to fungal-caused diseases, helping plant-breeding programs.O fungo Fusarium solani (teleomorfo Haematonectria haematococca apresenta uma expressiva importância na agricultura por ser considerado patógeno para várias culturas de interesse econômico causando doença conhecida por podridão das raízes, além de ser patógeno aos animais e ao homem, provocando nestes últimos, micoses superficiais e sistêmicas. A complexidade associada a sua identificação correta através de métodos tradicionais justifica os esforços de usar marcadores moleculares para caracterização dos isolados. Neste trabalho, três métodos baseados na tecnologia da PCR (um por ribotipagem por PCR e dois por impressão genética por PCR foram utilizados para investigar a variabilidade molecular de dezoito isolados de F. solani de quatro Estados brasileiros, coletados de diferentes substratos. A análise genética revelou a
Oct 2, 2006 ... RP-N (15941482) ..... Cloning of the nucleocapsid protein gene of peste des petits ruminants virus: relationship to other Morbillivuruses. J. General Virol. 75:233-237. Diallo A, Barrett T, Barbron M, Shaila MS, Taylor WP ...
These include DNA cloning for sequencing, DNA based phylogeny, or functional analysis of genes; the diagnosis of hereditary diseases; the identification of genetic finger prints (used in ... Strand separation (denaturing) of the double stranded sample .... study with 30 clinical specimen 18AH and 12VF from. 20 eyes with the ...
Marsh, Jane W; Tulenko, Mary M; Shutt, Kathleen A; Thompson, Angela D; Weese, J Scott; Songer, J Glenn; Limbago, Brandi M; Harrison, Lee H
Clostridium difficile is the primary known cause of antibiotic-associated diarrhea. Diarrheal disease in food animals due to C. difficile infection has been well documented. Recently, reports of C. difficile infections in patients with no known risk factors for disease have raised concern of community acquisition through food animals and food. In this study, multi-locus variable number tandem repeat analysis (MLVA) was performed on a collection of 97C. difficile isolates of human, animal and food origin belonging to either the North American pulsed-field type (NAP) 1 or NAP7/NAP8. MLVA discriminated between NAP1 and NAP7/NAP8 populations. Three clusters of food, food animal and human NAP1 isolates were highly related by MLVA. These data suggest the possibility of either laboratory contamination or widespread distribution of clonal C. difficile populations. Community-associated NAP1 isolates were unrelated to NAP1 food and food animal isolates. Two MLVA loci were absent and 1 was invariant in all NAP7/NAP8 isolates. Therefore, MLVA discrimination was not sufficient to make assessments regarding the genetic associations among food, food animal and human isolates belonging to the NAP7/NAP8 pulsovar. Rigorous epidemiologic and laboratory investigations that employ highly discriminatory genotyping methods are necessary to compare C. difficile isolates from food and food animals to those from humans. Copyright © 2011 Elsevier Ltd. All rights reserved.
Full Text Available Abstract Background C. difficle spores in the environment of patients with C. difficile associated disease (CDAD are difficult to eliminate. Bleach (5000 ppm has been advocated as an effective disinfectant for the environmental surfaces of patients with CDAD. Few alternatives to bleach for non-outbreak conditions have been evaluated in controlled healthcare studies. Methods This study was a prospective clinical comparison during non-outbreak conditions of the efficacy of an accelerated hydrogen peroxide cleaner (0.5% AHP to the currently used stabilized hydrogen peroxide cleaner (0.05% SHP at manufacturer recommended use-dilution with respect to spore removal from toilets in a tertiary care facility. The toilets used by patients who had diarrhea with and without C. difficile associated disease (CDAD were cultured for C. difficile and were monitored using an ultraviolet mark (UVM to assess cleaning compliance on a daily basis 5 days per week. A total of 243 patients and 714 samples were analysed. The culture results were included in the analysis only if the UVM audit from the same day confirmed that the toilet had been cleaned. Results Our data demonstrated that the efficacy of spore killing is formulation specific and cannot be generalized. The OxivirTB® AHP formulation resulted in statistically significantly (p = 0.0023 lower levels of toxigenic C. difficile spores in toilets of patients with CDAD compared to the SHP formulation that was routinely being used (28% vs 45% culture positive. The background level of toxigenic C. difficile spores was 10% in toilets of patients with diarrhea not due to CDAD. The UVM audit indicated that despite the enhanced twice-daily cleaning protocol for CDAD patients cleaning was not achieved on approximately 30 - 40% of the days tested. Conclusion Our data indicate that the AHP formulation evaluated that has some sporicidal activity was significantly better than the currently used SHP formulation. This AHP
John F. Pohl
Full Text Available Children with cystic fibrosis (CF often take proton pump inhibitors (PPIs, which helps improve efficacy of fat absorption with pancreatic enzyme replacement therapy. However, PPI use is known to be associated with Clostridium difficile-(C. diff- associated diarrhea (CDAD. We retrospectively evaluated the incidence of C. diff infection from all pediatric hospital admissions over a 5-year period at a single tertiary children's hospital. We found significantly more C. diff-positive stool tests in hospitalized patients with CF compared to patients with no diagnosis of CF. However, use of a PPI was not associated with an increased risk of CDAD in hospitalized CF patients. In summary, C. diff infection is more common in hospitalized pediatric CF patients although PPI use may not be a risk factor for CDAD development in this patient population.
Full Text Available Grace S Crowther,1 Mark H Wilcox1,2 1Faculty of Medicine and Health, University of Leeds, Leeds, UK; 2Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, UK Abstract: Treatment options for Clostridium difficile infection (CDI remain limited despite this usually nosocomial infection posing an urgent threat to public health. A major paradox of the management of CDI is the use of antimicrobial agents to treat infection, which runs the risk of prolonged gut microbiota perturbation and so recurrence of infection. Here, we explore alternative CDI treatment and prevention options currently available or in development. Notably, strategies that aim to reduce the negative effects of antibiotics on gut microbiota offer the potential to alter current antimicrobial stewardship approaches to preventing CDI. Keywords: treatment, prevention, CDI, SYN-004, vaccine, beta-lactams
Full Text Available Meng Xiao,1,* Jing-Wei Cheng,1,2,* Timothy Kudinha,3 Fanrong Kong,4 Ying-Chun Xu1,21Department of Clinical Laboratory, Peking Union Medical College Hospital, 2Faculty of Clinical Laboratory Diagnostics, Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China; 3School of Biomedical Sciences, The Charles Sturt University, Leeds Parade, Orange, 4Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR–Pathology West, Westmead Hospital, University of Sydney, Westmead, NSW, Australia*These authors contributed equally to this workIn a recent report, Dingle et al showed that national intervention programs aimed at judicious antimicrobial usage, especially restrictions to fluoroquinolones, contributed to a significant decrease in Clostridium difficile infection (CDI in England.1 This is considered an outstanding achievement in combating antimicrobial resistance worldwide.
Pant, C; Deshpande, A; Desai, M; Jani, B S; Sferra, T J; Gilroy, R; Olyaee, M
The incidence of Clostridium difficile infection (CDI) is increasing in the pediatric population. Pediatric recipients of solid organ transplantation (SOT) may be at a higher risk for CDI in part because of chemotherapy and prolonged hospitalization. We utilized data from the Healthcare Cost and Utilization Project Kids' Inpatient Database to study the incidence and outcomes related to CDI as a complicating factor in pediatric recipients of SOT. Our results demonstrate that hospitalized children with SOT have increased rates of infection, with the greatest risk for younger children with additional comorbidities and severe illness. The type of transplanted organ affects the risk for CDI, with the lowest incidence observed in renal transplant patients. The occurrence of CDI in the pediatric SOT population contributes to a greater length of stay and higher hospital charges. However, CDI is not an independent predictor of increased in- hospital mortality in these patients. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Full Text Available We investigated whether Clostridium difficile toxin alters colonic tissue levels of vasoactive intestinal peptide (VIP at the expense of changes in colonic motility in the isolated perfused rabbit left colon. Colonic inflammation was induced by the intracolonic administration of 10−8 M C. difflcile toxin. Strain gauge transducers were sewn onto the serosal surface of the colon to evaluate colonic motility. C. difflcile administration produced histologic changes consistent with epithelial damage. This was associated with an increased production of prostaglandin E2 and thromboxane B2. Tissue levels of VIP but not substance P were significantly reduced. This was associated with an increased number of contractions per minute and an average force of each colonic contraction. These results suggest that tissue levels of VIP are suppressed by C. difflcile and may participate in colonic dysmotility during active inflammation.
Cruz-Rodríguez, Nora Cecilia; Hernández-García, Raúl; Salinas-Caballero, Ana Gabriela; Pérez-Rodríguez, Edelmiro; Garza-González, Elvira; Camacho-Ortiz, Adrián
A high consumption of clindamycin was noted in an orthopedics ward with high rates of Clostridium difficile infection (CDI). We restricted clindamycin for the entire ward. A reduction of 88% in CDI (1.07 to 0.12 × 1,000 patients-days, P = .056) and 84% for all-cause diarrhea (2.40 to 0.38 × 1,000 patients-days, P = .021) was achieved. Clindamycin was reduced 92.61% without an increase in other antibiotics. We identified high consumption of clindamycin as a risk factor for CDI. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.
Full Text Available An 80-year-old man was diagnosed to have pneumonia and advanced chronic kidney disease. He presented with anuria and hemodialysis, by temporary femoral catheter, was initiated. He was empirically treated with imipenem/cilastatin 500 mg/24 h after hemodialysis. After 10 days of antibiotic intake, he developed severe diarrhea. Diagnosis of Clostridium difficile (CD-associated diarrhea was confirmed by detection of the toxins A and B in his stool. Imipenem therapy was discontinued; Vancomycin 500 mg orally every 6 h and 1000 mg per rectum every day was added. After two weeks of this treatment, the patient reported complete resolution of the diarrhea and stool samples were negative for Clostridium toxin. In this case, the most possible cause of CD colitis was considered to be imipenem because of the temporal relationship between exposure to the drug and onset of symptoms.
Kai Markus Schneider
Full Text Available Clostridium difficile infection (CDI represents one of the most common healthcare-associated infections. Due to increasing numbers of recurrences and therapy failures, CDI has become a major disease burden. Studies have shown that fecal microbiota transplantation (FMT can both be a safe and highly efficacious therapy for patients with therapy-refractory CDI. However, patients undergoing solid organ transplantation are at high risk for CDI due to long-term immunosuppression, previous antibiotic therapy, and proton pump inhibitor use. Additionally, these patients may be especially prone to adverse events related to FMT. Here, we report a successful FMT in a patient with severe therapy-refractory CDI after liver transplantation.
Full Text Available Clostridium difficile causes antibiotic-associated diarrhea and pseudomembraneous colitis and is responsible for a large and increasing fraction of hospital-acquired infections. Fecal microbiota transplantation (FMT is an alternate treatment option for recurrent C. difficile infection (RCDI refractory to antibiotic therapy. It has recently been discussed favorably in the clinical and scientific communities and is receiving increasing public attention. However, short- and long-term health consequences of FMT remain a concern, as the effects of the transplanted microbiota on the patient remain unknown. To shed light on microbial events associated with RCDI and treatment by FMT, we performed fecal microbiota analysis by 16S rRNA gene amplicon pyrosequencing of 14 pairs of healthy donors and RCDI patients treated successfully by FMT. Post-FMT patient and healthy donor samples collected up to one year after FMT were studied longitudinally, including one post-FMT patient with antibiotic-associated relapse three months after FMT. This analysis allowed us not only to confirm prior reports that RCDI is associated with reduced diversity and compositional changes in the fecal microbiota, but also to characterize previously undocumented post-FMT microbiota dynamics. Members of the Streptococcaceae, Enterococcaceae, or Enterobacteriaceae were significantly increased and putative butyrate producers, such as Lachnospiraceae and Ruminococcaceae were significantly reduced in samples from RCDI patients before FMT as compared to post-FMT patient and healthy donor samples. RCDI patient samples showed more case-specific variations than post-FMT patient and healthy donor samples. However, none of the bacterial groups were invariably associated with RCDI or successful treatment by FMT. Overall microbiota compositions in post-FMT patients, specifically abundances of the above-mentioned Firmicutes, continued to change for at least 16 weeks after FMT, suggesting that
Brandon R Anjuwon-Foster
Full Text Available In the human intestinal pathogen Clostridium difficile, flagella promote adherence to intestinal epithelial cells. Flagellar gene expression also indirectly impacts production of the glucosylating toxins, which are essential to diarrheal disease development. Thus, factors that regulate the expression of the flgB operon will likely impact toxin production in addition to flagellar motility. Here, we report the identification a "flagellar switch" that controls the phase variable production of flagella and glucosylating toxins. The flagellar switch, located upstream of the flgB operon containing the early stage flagellar genes, is a 154 bp invertible sequence flanked by 21 bp inverted repeats. Bacteria with the sequence in one orientation expressed flagellum and toxin genes, produced flagella, and secreted the toxins ("flg phase ON". Bacteria with the sequence in the inverse orientation were attenuated for flagellar and toxin gene expression, were aflagellate, and showed decreased toxin secretion ("flg phase OFF". The orientation of the flagellar switch is reversible during growth in vitro. We provide evidence that gene regulation via the flagellar switch occurs post-transcription initiation and requires a C. difficile-specific regulatory factor to destabilize or degrade the early flagellar gene mRNA when the flagellar switch is in the OFF orientation. Lastly, through mutagenesis and characterization of flagellar phase locked isolates, we determined that the tyrosine recombinase RecV, which catalyzes inversion at the cwpV switch, is also responsible for inversion at the flagellar switch in both directions. Phase variable flagellar motility and toxin production suggests that these important virulence factors have both advantageous and detrimental effects during the course of infection.
Weingarden, Alexa R; Chen, Chi; Bobr, Aleh; Yao, Dan; Lu, Yuwei; Nelson, Valerie M; Sadowsky, Michael J; Khoruts, Alexander
Fecal microbiota transplantation (FMT) has emerged as a highly effective therapy for refractory, recurrent Clostridium difficile infection (CDI), which develops following antibiotic treatments. Intestinal microbiota play a critical role in the metabolism of bile acids in the colon, which in turn have major effects on the lifecycle of C. difficile bacteria. We hypothesized that fecal bile acid composition is altered in patients with recurrent CDI and that FMT results in its normalization. General metabolomics and targeted bile acid analyses were performed on fecal extracts from patients with recurrent CDI treated with FMT and their donors. In addition, 16S rRNA gene sequencing was used to determine the bacterial composition of pre- and post-FMT fecal samples. Taxonomic bacterial composition of fecal samples from FMT recipients showed rapid change and became similar to the donor after the procedure. Pre-FMT fecal samples contained high concentrations of primary bile acids and bile salts, while secondary bile acids were nearly undetectable. In contrast, post-FMT fecal samples contained mostly secondary bile acids, as did non-CDI donor samples. Therefore, our analysis showed that FMT resulted in normalization of fecal bacterial community structure and metabolic composition. Importantly, metabolism of bile salts and primary bile acids to secondary bile acids is disrupted in patients with recurrent CDI, and FMT corrects this abnormality. Since individual bile salts and bile acids have pro-germinant and inhibitory activities, the changes suggest that correction of bile acid metabolism is likely a major mechanism by which FMT results in a cure and prevents recurrence of CDI.
Codella, James; Safdar, Nasia; Heffernan, Rick; Alagoz, Oguzhan
Control of Clostridium difficile infection (CDI) is an increasingly difficult problem for health care institutions. There are commonly recommended strategies to combat CDI transmission, such as oral vancomycin for CDI treatment, increased hand hygiene with soap and water for health care workers, daily environmental disinfection of infected patient rooms, and contact isolation of diseased patients. However, the efficacy of these strategies, particularly for endemic CDI, has not been well studied. The objective of this research is to develop a valid, agent-based simulation model (ABM) to study C. difficile transmission and control in a midsized hospital. We develop an ABM of a midsized hospital with agents such as patients, health care workers, and visitors. We model the natural progression of CDI in a patient using a Markov chain and the transmission of CDI through agent and environmental interactions. We derive input parameters from aggregate patient data from the 2007-2010 Wisconsin Hospital Association and published medical literature. We define a calibration process, which we use to estimate transition probabilities of the Markov model by comparing simulation results to benchmark values found in published literature. In a comparison of CDI control strategies implemented individually, routine bleach disinfection of CDI-positive patient rooms provides the largest reduction in nosocomial asymptomatic colonization (21.8%) and nosocomial CDIs (42.8%). Additionally, vancomycin treatment provides the largest reduction in relapse CDIs (41.9%), CDI-related mortalities (68.5%), and total patient length of stay (21.6%). We develop a generalized ABM for CDI control that can be customized and further expanded to specific institutions and/or scenarios. Additionally, we estimate transition probabilities for a Markov model of natural CDI progression in a patient through calibration. © The Author(s) 2014.
Merlo, Gregory; Graves, Nicholas; Brain, David; Connelly, Luke B
Clostridium difficile is the most common cause of hospital-acquired diarrhea in Australia. In 2013, a randomized controlled trial demonstrated the effectiveness of fecal microbiota transplantation (FMT) for the treatment of recurrent Clostridium difficile infection (CDI). The aim of this study is to evaluate the cost-effectiveness of fecal microbiota transplantation-via either nasoduodenal or colorectal delivery-compared with vancomycin for the treatment of recurrent CDI in Australia. A Markov model was developed to compare the cost-effectiveness of fecal microbiota transplantation compared with standard antibiotic therapy. A literature review of clinical evidence informed the structure of the model and the choice of parameter values. Clinical effectiveness was measured in terms of quality-adjusted life years. Uncertainty in the model was explored using probabilistic sensitivity analysis. Both nasoduodenal and colorectal FMT resulted in improved quality of life and reduced cost compared with vancomycin. The incremental effectiveness of either FMT delivery compared with vancomycin was 1.2 (95% CI: 0.1, 2.3) quality-adjusted life years, or 1.4 (95% CI: 0.4, 2.4) life years saved. Treatment with vancomycin resulted in an increased cost of AU$4094 (95% CI: AU$26, AU$8161) compared with nasoduodenal delivery of FMT and AU$4045 (95% CI: -AU$33, AU$8124) compared with colorectal delivery. The mean difference in cost between colorectal and nasoduodenal FMT was not significant. If FMT, rather than vancomycin, became standard care for recurrent CDI in Australia, the estimated national healthcare savings would be over AU$4000 per treated person, with a substantial increase in quality of life. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.