Clostridium Difficile Isolates Research Articles

Isolation and Identification of Clostridium difficile from Antibiotic- Associated Diarrhea and Colitis in Iraqi children, using API20A Anaerobic system.

Clostridium difficile were isolated by 51 (21.25%) from a total of 240 stool sample collected from children having diarrhea and colitis at ages from after birth to 15 years old from Baghdad hospitals, who were under treatment with broad spectrum antibiotics, and Sample were taken during the period of first of June 2013 till the end of april 2014. Also 80 stool samples were collected from healthy ,non diarrhea children as controls. Morphological and API 20A tests were used for the identification of this bacterium to evaluate the performance of the API 20A anaerobe system in definitively identifying strains of C. difficile. . This study shows that females were more infected than males .Overall positivity was (21.25%)in this study group compared to controls (P<0.05). The isolation percent from age <5years was (18.75%) , while it in age>5years was( 2. 5 %) . It was found that this percent decreased with age get older.

Isolation, molecular typing and antimicrobial resistance of Clostridium difficile in dogs and cats in Lanzhou city of Northwest China.

Clostridium difficile infection (CDI) in human and animals belonged usually to antibiotic-associated diarrhea, ranging in severity from mild to life-threatening intestinal tract illnesses. This study aimed to isolation and characterization, toxin genes test, molecular typing, and drug sensitivity of Clostridium difficile (C. difficile) which were isolated from clinical diseased dogs and cats. A total of 247 clinical samples were collected from five animal hospitals in Lanzhou City of Northwest China, of which dogs and cats accounted for 74.9% (185/247) and 25.1% (62/247), respectively. We successfully identified 24 C. difficile strains by 16S rRNA and Matrix-Assisted Laser Desorption/Ionization Time of Fight Mass Spectroscopy (MALDI-TOF-MS). 10.3% (19/185) of dogs and 8.1% (5/62) of cats were positive for C. difficile. Among them, 16 strains were toxic and 8 were non-toxic, with a toxic rate of 57.9% (11/19) in dogs and 100% (5/5) in cats. A total of 10 STs and 10 RTs were identified in this study. The percentages of ST42 (RT106) and ST2 (RT014/LW01) among 16 toxic strains were 41.7 and 12.5%, respectively. However, ST3 (RT001), ST1 (RT027), ST133 (LW04), and ST-UN (LW04) had only one strain. ST42 (RT106) was the most common genotype and RT027 strain was first isolated in China from pets. Antimicrobial susceptibility test showed that isolates were extremely sensitive to vancomycin and metronidazole but were resistant to erythromycin and ciprofloxacin. The drug resistant rates to clindamycin, levofloxacin, moxifloxacin and meropenem were 62.5, 20.8, 16.7, and 8.3%, respectively. In conclusion, C. difficile was quietly prevalent in dogs and cats in Lanzhou city with RT106 and RT014 as the main ribotypes. The CDI in pets should be paying more attention and further studies are needed.

Effects of reported beta‐lactam allergies on pneumonia outcomes in lung transplant recipients

The effects of reported beta-lactam allergies on clinical outcomes have been understudied in lung transplant recipients. We evaluated reported beta-lactam allergies on clinical outcomes in this population. A single-center retrospective cohort analysis was performed. One hundred and nine lung transplant recipients were identified and screened for a diagnosis of pneumonia. This cohort was divided into those with a reported beta-lactam allergy and those without a beta-lactam allergy. Antibiotic use was compared between groups. We also compared several clinical metrics, including rates of readmission, mortality, Clostridium difficile infection (CDI), allograft dysfunction, and isolation of carbapenem or fluoroquinolone non-susceptible organisms after treatment. Of the 109 lung transplant recipients, 18 (16.5%) were identified as having a reported beta-lactam allergy. Patients with a beta-lactam allergy label (BLAL) were found to have decreased utilization of beta-lactams (p<.001) and a trend toward increased use of carbapenems (p = .062) and aztreonam (p = .080). BLAL patients were found to have higher rates of CDI (p = .049) but were not found to have increased readmissions, mortality, allograft dysfunction, or isolation of carbapenem or fluoroquinolone non-susceptible organisms. Patients without a BLAL were found to have higher rates of acute kidney injury (AKI) (p = .035). Lung transplant recipients with BLAL are more likely to develop CDI, possibly due to increased use of carbapenems. We also found that patients without beta-lactam allergy were more likely to develop AKI. A multicenter study with a larger sample size might clarify the individual contributions of mutually confounding clinical parameters.

Assessment of animal diseases caused by bacteria resistant to antimicrobials: rabbits.

In this opinion, the antimicrobial‐resistant bacteria responsible for transmissible diseases that constitute a threat to the health of farmed rabbits have been assessed. The assessment has been performed following a methodology based on information collected through an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play on antimicrobial resistance in clinical isolates of Pasteurella multocida, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bordetella bronchiseptica, Clostridium difficile, Clostridium perfringens and Clostridium spiroforme is provided. Among these bacteria, none were identified as being the most relevant antimicrobial‐resistant bacteria in rabbits in the EU due to the very limited scientific evidence available.

Genetically related Clostridium difficile from water sources and human CDI cases revealed by whole-genome sequencing.

Clostridium difficile isolates from the environment are closely related to those from humans, indicating a possible environmental transmission route for C. difficile infection (CDI). In this study, C. difficile was isolated from 47.3% (53/112) of lake/pond, 23.0% (14/61) of river, 20.0% (3/15) of estuary and 0.0% (0/89) of seawater samples. The most common toxigenic strain isolated was C. difficile PCR ribotype (RT) 014/020 (10.5%, 8/76). All water isolates were susceptible to fidaxomicin, metronidazole, rifaximin, amoxicillin/clavulanic acid, moxifloxacin and tetracycline. Resistance to vancomycin, clindamycin, erythromycin and meropenem was detected in 5.3% (4/76), 26.3% (20/76), 1.3% (1/76) and 6.6% (5/76) of isolates, respectively. High-resolution core-genome analysis was performed on RT 014/020 isolates of water origin and 26 clinical RT 014/020 isolates from the same year and geographical location. Notably, both human and water strains were intermixed across three sequence types (STs), 2, 13 and 49. Six closely related groups with ≤10 core-genome single nucleotide polymorphisms were identified, five of which comprised human and water strains. Overall, 19.2% (5/26) of human strains shared a recent genomic relationship with one or more water strains. This study supports the growing hypothesis that environmental contamination by C. difficile plays a role in CDI transmission.

Prevalence of Clostridium difficile in Hospital Environment within Yola Adamawa State Nigeria

Introduction: Clostridium difficile infection (CDI) is an emerging health problem in hospital setting. The ability of the spores to persist in the environment is a key factor in rates of infection. Clostridium difficile has also been described as one of the leading cause of nosocomial diarrhea. It is responsible for an increase in hospital stay with high healthcare and economic repercussions. Objectives: This study was aimed at determining the prevalence and antimicrobial susceptibility profile of Clostridium difficile isolated from surfaces within hospital environment in Yola Adamawa State Nigeria. Materials and Methods: A total of 150 surface samples were collected from different wards of two hospitals (Specialist Hospital Yola (SHY) and Federal Medical Centre Yola (FMCY)) using moistened swabs. Clostridium difficile isolates were obtained by enriching and culturing samples in cycloserine-cefoxitin fructose broth (CCFB) and cycloserine-cefoxitin fructose agar (CCFA) respectively. Susceptibility test (MIC determination) was done by well diffusion technique on Mueller Hinton agar supplemented with 5% sodium taurocholate. Results: A total of 18 (12%) Clostridium difficile were recovered from the two hospitals sampled. FMC had a prevalence rate of 13.3% with table top, toilet, window and bed sheets as sites implicated while SHY had a prevalence rate of 10.7% with bed sheet, bed railing and window as implicated sites. The antibiotic susceptibility test reveals that Clostridium difficile isolates obtained were resistant to the antibiotics tested which includes Ciprofloxacin (MIC &gt;64 µg/ml), Erythromycin (MIC &gt;64 µg/ml), Metronidazole (MIC 64 µg/ml), Tetracycline (MIC &gt; 128 µg/ml) and Clindamycin (MIC &gt; 64 µg/ml). Conclusions: The study depicts that multidrug resistant Clostridium difficile is prevalent in hospital environments within Yola Adamawa State Nigeria. The need for the sensitization of healthcare workers to improve understanding of Clostridium difficile transmission, treatment, management and prevention is of paramount importance.

Isolation and identification of Clostridium difficile from cases of diarrhea in young farm animals, and the determination of antimicrobial susceptibility

Isolation and identification of Clostridium difficile from cases of diarrhea in young farm animals, and the determination of antimicrobial susceptibility

Characteristics of Clostridium difficile isolates and the burden of hospital-acquired Clostridium difficile infection in a tertiary teaching hospital in Chongqing, Southwest China

BackgroundClostridium difficile infection (CDI), especially hospital-acquired Clostridium difficile infection (HA-CDI), continues to be a public health problem and has aroused great concern worldwide for years. This study aimed to elucidate the clinical and epidemiological features of HA-CDI and the characteristics of C.difficile isolates in Chongqing, Southwest China.MethodsA case-control study was performed to identify the clinical incidence and risk factors of HA-CDI. C. difficile isolates were characterised by polymerase chain reaction (PCR) ribotyping, multilocus sequence typing (MLST), toxin gene detection and antimicrobial susceptibility testing.ResultsOf the 175 suspicious patients, a total of 122 patients with antibiotic-associated diarrhea (AAD) were included in the study; among them, 38 had HA-CDI. The incidence of AAD and HA-CDI was 0.58 and 0.18 per 1000 patient admissions, respectively. Chronic renal disease and cephalosporin use were independent risk factors for HA-CDI. Fifty-five strains were assigned into 16 sequence types (STs) and 15 ribotypes (RTs). ST2/RT449 (8, 14.5%) was the predominant genotype. Of the 38 toxigenic isolates, A + B + CDT- isolates accounted for most (34, 89.5%) and 1 A + B + CDT+ isolate emerged. No isolate was resistant to vancomycin, metronidazole or tigecycline, with A-B-CDT- being more resistant than A + B + CDT-.ConclusionsDifferent genotypes of C. difficile strains were witnessed in Chongqing, which hinted at the necessary surveillance of HA-CDI. Adequate awareness of patients at high risk of HA-CDI acquisition is advocated and cautious adoption of cephalosporins should be highlighted.

Surveillance of antimicrobial susceptibilities reveals high proportions of multidrug resistance in toxigenic Clostridium difficile strains in different areas of Poland

Two hundred and fifty-three non-duplicate toxigenic Clostridium difficile isolates, collected from February 2012 to December 2014, were evaluated for phenotypic resistance to ten antimicrobial drugs with the E-test gradient diffusion method. All strains of C. difficile were susceptible to metronidazole, vancomycin, and tigecycline. The metronidazole MIC values of the hyperepidemic PCR-ribotypes RT027 and RT176 were higher than those of non-epidemic PCR-ribotypes (p < 0.05, as evidenced by Mann-Whitney U test). In contrast, vancomycin susceptibility did not differ between hyperepidemic and non-epidemic strains, although the difference was almost significant (p = 0.065). Clostridium difficile RT027 and RT176 isolates could be assessed to five and four different susceptibility patterns, respectively, representing various combinations of resistance to different antimicrobial classes. A single point mutation (Thr82Ile) in the gyrA gene was detected in 11 (78.6%) of 14 isolates with high level of resistance to ciprofloxacin and moxifloxacin and four different types of single point mutations (Arg447Lys, Ser416Ala, Asp426Val, Asp426Asn) in the gyrB gene were detected in 4 strains, also with high level of resistance to ciprofloxacin and moxifloxacin. Four different point mutations were detected in the rpoB gene in 21 rifampicin-resistant strains of which one has not been reported previously, Gln489Leu. This study demonstrates the presence of multidrug-resistant C. difficile strains in Polish hospitals over the study period, irrespective of geographical location or reference level of the hospital.

Phenotypic and Genotypic Characteristics of Clostridium difficile Isolates in Patients with Type 2 Diabetes in Iran.

PurposeThis study aimed to investigate the phenotypic and genotypic characterization of Clostridium difficile isolates in type 2 diabetes patients with hospital-acquired diarrhea in four teaching hospitals in Isfahan, Iran.Patients and MethodsA total of 104 hospitalized patients with type 2 diabetes and nosocomial diarrhea were included in the current study over a 2-year period (2015–2017). C. difficile isolates were characterized by conventional microbiological methods including the presence of toxin genes, antibiotic resistance testing and molecular methods including multilocus sequence typing (MLST) and random amplification of polymorphic DNA (RAPD).ResultsAll 21 C. difficile isolates (20.2%) were detected from 104 studied patients. All isolates were susceptible to metronidazole and vancomycin. The antimicrobial resistance rates were distinctly higher for clindamycin and for moxifloxacin. Based on PCR amplification of tcdA and tcdB, 13 isolates (12.5%) carried both of these genes and were considered toxigenic. Thirteen toxigenic C. difficile strains were classified into two sequence types (STs), that is, ST54 and ST2 types. The RAPD-PCR amplification patterns of the detected toxigenic C. difficile revealed three distinct but related RAPD clusters. RAPD cluster 1 had the highest similarity with RAPD types 2 and 3.ConclusionA relatively high rate of CDI was observed in patients with type 2 diabetes and was associated with poorer health outcomes. These patients were exposed to multiple antibiotics and other therapeutic agents. We recommend close screening for the coexistence of CDI and type 2 diabetes in patients with diarrhea using a combination of conventional and molecular methods.

Overview report on the application of double digest selective label (DDSL) bacteria genotyping technique for identification of strains and certification of commercially used bacteria

The objective of this report is to demonstrate the potential of the proposed simple typing technique, double digest selective label (DDSL), which was initially developed to identify clinical isolates of Pseudomonas aeruginosa, for other bacterial species including Salmonella enterica, Clostridium difficile, Staphylococcus aureus, and Bacillus subtilis. The technique is based on digestion of bacterial genomic DNA with two restriction enzymes and simultaneous labeling fragments with biotinylated deoxycytidine triphosphate in fill-in reaction by Taq polymerase. The number and distribution of generated DNA fragments can be optimized by selecting restriction enzymes. DDSL is fast, reproducible, cost effective and sufficiently discriminatory typing method applicable for identification of bacterial strains at laboratories having no access to expensive sequencing equipment and with limited funding and lack of skilled personnel. Data concerning the potential of the technique for short-term epidemiological surveillance and bacterial strain certification are presented and discussed. Multiple locus variable number tandem repeat analysis performed on our set of Clostridium difficile isolates did not demonstrate sufficient discriminatory power both with TR6 and TR10 loci on a set of 24 isolates. In contrast, the DDSL analysis resolved all isolates into individual strains.

Isolation and characterization of Clostridium difficile from a small survey of wastewater, food and animals in New Zealand.

The objective of this study was to undertake a microbiological survey of foods, animal faeces and wastewater samples for Clostridium difficile, and determine the genotypes and antimicrobial susceptibilities of isolates. A total of 211 samples were tested for C. difficile using culture methods. Thirteen toxigenic C. difficile isolates were obtained; ten from wastewater samples, one each from pig and duck faeces and another from a raw meat product. Eight PCR-ribotypes (RTs) were identified, including two novel RTs (878 and 879). Single-nucleotide polymorphism analysis using WGS data for all isolates provided greater discrimination between C. difficile isolates within the same RT and multilocus sequence typing (MLST) profiles. All C. difficile isolates were found to be susceptible to the first-line human antimicrobials used to treat C. difficile infection. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to report the isolation of Clostridium difficile from animals, food and wastewater in New Zealand (NZ) and provides important data with respect to ribotypes and multilocus sequence typing profiles, whole genome sequence and antimicrobial susceptibilities. The results highlight the need for further investigations into the epidemiology of C. difficile in NZ and to elucidate the role of the environmental and food sources as transmission routes of human infection.

Performance evaluation of a new matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, ASTA MicroIDSys system, in bacterial identification against clinical isolates of anaerobic bacteria

IntroductionMatrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been introduced for bacterial identification. The ASTA MicroIDSys system (ASTA, Suwon, Korea) is a new MALDI-TOF MS system developed for species identification of microorganisms. We evaluated the performance of MicroIDSys against clinical isolates of anaerobic bacteria. Material and methodsA total of 370 non-duplicated clinical isolates of anaerobic bacteria were tested in this study. Bacterial identification with MicroIDSys was performed with a direct smear method, and measured spectra were analyzed using respective software. The results of MicroIDSys were compared with the results of Bruker Biotyper and 16S rRNA sequencing. ResultsThe overall agreement rates for the 370 clinical isolates (34 genera and 99 species) were 95.4% (353/370) at the genus level and 91.6% (n = 340) at the species level. Only 17 isolates were incorrectly identified at the genus level: five misidentifications and 12 unidentifications. The MicroIDSys system exhibited excellent performance in the identification of clinically relevant bacterial species. Most of the Bacteroides isolates (98.0%, 99/101) and all of the Clostridium difficile (100%, n = 11), Clostridium perfringens (100%, n = 10), Finegoldia magna (100%, n = 11), and Parvimonas micra (100%, n = 10) isolates were correctly identified at the species level. ConclusionThe MicroIDSys system proved useful in the identification of anaerobic bacteria, especially clinically relevant species. This system could be of use in clinical microbiology laboratories as a primary tool for identifying anaerobic bacteria.

Curcumin: A natural derivative with antibacterial activity against Clostridium difficile

ObjectivesThe rapid emergence of hypervirulent Clostridium difficile (C. difficile) isolates and the paucity of effective anti-clostridial antibiotics call for extensive research to identify new treatment options. This study aimed to test the anti-clostridial activity of bioactive extracts of turmeric, which is a natural herb widely known for its profound medicinal properties. MethodsThe MICs of turmeric derivatives were determined against 27 C. difficile strains, including hypervirulent (BI/NAP1/027) and clinical toxigenic isolates. Additionally, their ability to inhibit C. difficile toxin production and spore formation was investigated. Furthermore, the safety profiles of turmeric derivatives regarding their effects on human gut microflora – such as Bacteroides, Lactobacillus and Bifidobacterium – were evaluated. ResultsCurcuminoids, the major phytoconstituents of turmeric – including curcumin, demethoxycurcumin and bisdemethoxycurcumin – inhibited growth of C. difficile at concentrations ranging from 4 to 32μg/mL. Additionally, curcuminoids showed no negative effect on major populating species of the human gut. Curcumin was more effective than fidaxomicin in inhibiting C. difficile toxin production, but less so in inhibiting spore formation. ConclusionThe findings suggest that curcumin has potential as an anti-clostridial agent. More work is needed to further investigate the efficacy of curcumin as a stand-alone drug or as a supplement of current drugs of choice, as it has no antagonistic activities but might overcome their drawbacks.

Quality assurance for genotyping and resistance testing of Clostridium (Clostridioides) difficile isolates - Experiences from the first inter-laboratory ring trial in four German speaking countries

Clostridium (Clostridioides) difficile is a major cause of nosocomial diarrhoea. A first inter-laboratory ring trial was performed in four European countries to evaluate the genotyping and antibiotic susceptibility testing (AST) accuracy.Six C. difficile isolates representing the epidemiologic important ribotypes (RT), RT001, RT002, RT010, RT014, RT027, and RT078 were blinded and send to 21 participating laboratories. Participants tested the samples with their genotyping and AST methods in use for concordance with reference.A total of 21 genotyping- and 14 antimicrobial susceptibility data sets were obtained. Ribotyping (11 participants) correctly identified most RTs (median 91% concordance rate) except for RT002, which was misidentified in 4/11 reports. However, this isolate was correctly asserted to RT002 after an update of a publicly available ribotyping database. Multilocus sequence typing, surface layer sequence typing, DNA microarray based genotyping, and whole genome sequencing, which were used by 1–3 participants, identified all six isolates correctly. AST was done by epsilometry by the participants and compared to agar dilution data determined by the coordinating reference centre. Susceptibilities against metronidazole, moxifloxacin, and vancomycin were correctly identified in 235 of 237 cases and in accordance to agar dilution as the gold standard.Genotyping of the C. difficile test strains revealed a remarkable high concordance on the level of ribotypes with a wide variety of methods. Epsilometry appears to be a reliable method for AST of C. difficile isolates in routine clinical microbiology laboratories.

Changes in molecular epidemiology and antimicrobial resistance profiles of Clostridioides (Clostridium) difficile strains in the United States between 2011 and 2017

PCR ribotyping and antimicrobial susceptibility testing were used to characterize 940 Clostridioides (Clostridium) difficile isolates collected from 26 U S. hospitals over three time periods from 2011 to 2017. The proportion of ribotype (RT) 027 isolated during the three surveys decreased significantly over time from 31% in 2011–2012, to 22% in 2013–2014, and to 14% in 2015–2017 (p < 0.001 and p = 0.010, respectively), while we observed an increase in prevalence of RT106, that rose from 7% in our first survey to 19% of isolates in our last survey (p < 0.001). In addition, both RT056 and RT002 rose from 3% to 10% (p < 0.001). The proportions of all other ribotypes remained steady over time, and RT014/020 was the third most common strain type in our convenience sample in the final survey. Overall, resistance to moxifloxacin, rifampin, and vancomycin decreased during our studies, mainly due to the decline in RT027 isolates. A decrease in moxifloxacin resistance and an increase in tetracycline resistance were found among RT027 strains isolated in the last survey. Although the proportion of RT027 isolates declined, multidrug resistance among this ribotype continues to be common.

Clostridium difficile isolated from faecal samples in patients with ulcerative colitis

BackgroundUlcerative colitis (UC) is an inflammatory bowel disease (IBD) that is widely identified worldwide. This study aimed to investigate the phenotypic characterization and molecular typing of Clostridium difficile isolates among patients with UC at an inflammatory bowel disease clinic in Iran.MethodsIn this cross-sectional study, conducted from April 2015 to December 2015, 85 UC patients were assessed for C.difficile infection (CDI). C. difficile isolates were characterized based on their toxin profile and antimicrobial resistance pattern. Multi-locus sequence typing analysis (MLST) and PCR ribotyping were performed to define the genetic relationships between different lineages of toxigenic strains.ResultsThe prevalence of C. difficile isolates was 31.8% (27/85) in patients, of those 15 patients (17.6%) had CDI. Three different sequence types (STs) identified based on MLST among the toxigenic isolates, that is ST54 (33.3%), ST2 (53.3%), and ST37 (13.6%).C. difficile strains were divided into four different PCR-ribotypes (012, 014, 017 and IR1). The most common ribotype was 014 accounting for 48.3% (7/15) of all strains. The strains isolated during the first episode and recurrence of CDI usually belonged to PCR ribotype 014 (ST2). A high rate of CDI recurrence (14.1%, 12/85) experienced in UC patients. Colonization of the gastrointestinal tract with non-toxigenic C. difficile strains was frequent among patients with mild disease.All C. difficile isolates were susceptible to metronidazole, and vancomycin, 86 and 67% of isolates were resistant to clindamycin and erythromycin respectively. There was no correlation between the toxin type and antibiotic resistance (p > 0.05).ConclusionOverall CDI is rather prevalent in UC patients. All patients with CDI experienced moderate to severe disease and exposed to different antimicrobial and anti-inflammatory agents. Close monitoring and appropriate management including early detection and fast treatment of CDI will improve UC outcomes.

Clostridium difficile infection in cancer patients with hospital acquired diarrhea at the teaching hospitals in Iran: Multilocus sequence typing analysis (MLST) and Antimicrobial resistance pattern.

This study aimed to investigate the phenotype and genotype characterization of Clostridium difficile isolates among cancer patients with hospital-acquired diarrhea in 4 teaching hospitals in Isfahan, Iran. This was a cross sectional study conducted on adult (>18 years old) between April 2015 and May 2017. Over two years, 67 diarrheic fecal samples were collected. C. difficile isolates were characterized according to the presence of toxin genes and antibiotic resistance. Multilocus sequence typing (MLST) was performed to evaluate the genetic relationships between different lineages of toxigenic strains. Seven toxigenic and 12 non- toxigenic strains were detected among stool samples. Patients with a history of previous surgery during hospitalization were more than 7 times likely to develop Clostridium difficile infection (CDI). All isolates were susceptible to metronidazole, vancomycin and fusidic acid. Toxigenic C. difficile strains were divided into 3 different sequence types. The detected types were ST-54, ST-2 and ST-37, while none of the isolates was identified as ST-1 or ST-11. This is the first description of the MLST analysis of C. difficile strains isolated from cancer patients in Iran. All of the studied population were exposed to multiple antibiotics and chemotherapeutic agents. Further research and clinical studies are recommended in the treatment through good antimicrobial stewardship and prevention of C. difficile infection in all healthcare settings.

Molecular epidemiology of Clostridioides (previously Clostridium) difficile isolates from a university hospital in Minas Gerais, Brazil

The molecular epidemiology of 38 non-duplicate toxigenic Clostridioides (previously Clostridium) difficile isolates from inpatients from a hospital in Brazil during a 6-year period (2012–2017) were investigated by multilocus sequence typing (MLST) and ribotyping. These isolates were classified into 20 sequence types (ST), six (30%) of which were novel, revealing a high diversity in a single hospital. Classic hypervirulent strains ST1/RT027 and ST11/RT078 were not identified, while ST42 (almost all RT106) was the most common type, being detected in 11 (28.9%) strains. Noteworthy, six (15.8%) isolates were classified into five STs from clade 2, four of which were new ST and RT. Our study suggests that possible hypervirulent strains other than ST1/RT027 might be inadvertently circulating in Brazilian hospitals and highlights the importance of permanent surveillance on circulating strains in a national scale.

The emergence of metronidazole and vancomycin reduced susceptibility in Clostridium difficile isolates in Iran.

Clostridium difficile (C. difficile) is the main causative agent of antibiotic-associated diarrhoea (AAD) and pseudomembranous colitis. The accumulation of antimicrobial resistance in C. difficile strains can drive C. difficile infection (CDI) epidemiology. This study was undertaken to evaluate the antimicrobial resistance patterns of toxigenic C. difficile isolates cultured from diarrhoeal stool samples of hospitalised patients with suspected CDI in three tertiary care hospitals in Tehran, Iran. Two hundred and fifty diarrhoeal stool samples were investigated by toxigenic culture using cycloserine-cefoxitin-fructose agar and the VERO cell line. Antimicrobial susceptibility to metronidazole, vancomycin, clindamycin, tetracycline, and moxifloxacin was performed by disk diffusion and Etest methods on Brucella Blood Agar supplemented with hemin and vitamin K. Thirty-five stool samples (14.0%) proved positive using C. difficile toxigenic culture. According to Clinical and Laboratory Standards Institute breakpoints, the following resistance was identified in C. difficile isolates: metronidazole (2 of 35); moxifloxacin (7 of 35); clindamycin (18 of 35); and tetracycline (5 of 35). Using European Committee on Antimicrobial Susceptibility Testing breakpoints, three of 35 isolates showed reduced-susceptibility for vancomycin and 14 of 35 for metronidazole. In addition, the results showed a good correlation between the inhibition zone diameter (disk diffusion) and MIC values (Etest); Pearson correlation coefficient 0.7400.95 (P< 0.001). Multidrug resistance was observed in Iranian clinical toxigenic C. difficile isolates, including reduced susceptibility to first-line CDI treatment drugs. In addition, disk diffusion can be used as a cost-effective option for the antimicrobial susceptibility testing of C. difficile isolates.