BackgroundClostridioides difficile is a leading cause of infectious diarrhea in both humans and livestock. In particular, C. difficile strains belonging to sequence type (ST) 11 are common... Show moreBackgroundClostridioides difficile is a leading cause of infectious diarrhea in both humans and livestock. In particular, C. difficile strains belonging to sequence type (ST) 11 are common enteropathogens. The aim of this study was to determine the presence and genetic relatedness of C. difficile types in dairy cattle and calves.MethodDutch dairy farms were visited between February and December 2021. Feces was collected from adult dairy cattle and calves of two age categories (<4 weeks and 4 weeks-4 months). Fecal samples were also requested from dairy farmers, family members and employees. Fecal samples were cultured in an enrichment medium for 10–15 days and subcultured on solid media for capillary PCR ribotyping and whole genome sequencing.ResultsC. difficile was detected on 31 out of 157 (19.8%) dairy farms. The highest prevalence was found in calves <4 weeks (17.5%). None of the 99 human samples collected were positive. Thirty-seven cultured isolates belonged to 11 different PCR ribotypes (RT) of which RT695 (56.8%) and RT078/126 (16.2%) were most abundant. In the database of the Netherlands National Expertise Centre for C. difficile infections (CDI, >10.000 patient isolates), RT695 was found in only two patients with hospital-onset CDI, diagnosed in 2020 and 2021. Sequence analysis of 21C. difficile RT695 from cattle revealed that all isolates belonged to clade 5, ST11 and contained genes encoding toxin A, toxin B and binary toxin. RT695 strains carried antimicrobial resistance genes typically found in clade 5C. difficile. Groups of genetically related RT695 isolates were found between dairy farms, whereas identical strains were only present in individual farms.ConclusionsC. difficile was found in ∼20% of dairy farms with a predominance of the relatively unknown RT695. Isolates of RT695 belonged to the same clade and sequence type as RT078/126, which is recognized as an important zoonotic type. Show less
Clostridioides difficile infections (CDI) have a high morbidity and mortality rate and have always been considered a nosocomial disease. Nonetheless, the number of cases of community-acquired CDI... Show moreClostridioides difficile infections (CDI) have a high morbidity and mortality rate and have always been considered a nosocomial disease. Nonetheless, the number of cases of community-acquired CDI is increasing, and new evidence suggests additional C. difficile reservoirs exist. Pathogenic C. difficile strains have been found in livestock, domestic animals, and meat, so a zoonotic transmission has been proposed. Objective: The goal of this study was to isolate C. difficile strains in dogs at a veterinary clinic in Rio de Janeiro, Brazil, and characterize clinical and pathological findings associated with lower gastrointestinal tract disorders. Methods: Fifty stool samples and biopsy fragments from dogs were obtained and cultured in the CDBA selective medium. All suggestive C. difficile colonies were confirmed by MALDI-TOF MS and PCR (tpi gene). Vancomycin, metronidazole, moxifloxacin, erythromycin, and rifampicin were tested for antibiotic susceptibility. Biofilm, motility assays, and a PCR for the toxins (tcdA, tcdB, and cdtB), as well as ribotyping, were also performed. Results: Blood samples and colonic biopsy fragments were examined in C. difficile positive dogs. Ten animals (20%) tested positive for C. difficile by using stool samples, but not from biopsy fragments. Most C. difficile strains were toxigenic: six were A+B+ belonging to RT106; two were A+B+ belonging to RT014/020; and two were AB- belonging to RT010. All strains were biofilm producers. In the motility test, 40% of strains were as motile as the positive control, CD630 (RT012). In the disc diffusion test, two strains (RT010) were resistant to erythromycin and metronidazole; and another to metronidazole (RT014/020). In terms of C. difficile clinicopathological correlations, no statistically significant morphological changes, such as pseudomembranous and "volcano" lesions, were observed. Regarding hematological data, dogs positive for C. difficile had leucopenia (p = 0.02) and lymphopenia (p = 0.03). There was a significant correlation between senility and the presence of C. difficile in the dogs studied (p = 0,02). Conclusions: Although C. difficile has not been linked to canine diarrheal disorders, it appears to be more common in dogs with intestinal dysfunctions. The isolation of ribotypes frequently involved in human CDI outbreaks around the world supports the theory of C. difficile zoonotic transmission. Show less
Objectives: To assess the value of screening for Clostridioides difficile colonization (CDC) at hospital admission in an endemic setting.Methods: A multi-centre study was conducted at four... Show moreObjectives: To assess the value of screening for Clostridioides difficile colonization (CDC) at hospital admission in an endemic setting.Methods: A multi-centre study was conducted at four hospitals located across the Netherlands. Newly admitted patients were screened for CDC. The risk of development of Clostridioides difficile infection (CDI) during admission and 1-year follow-up was assessed in patients with and without colonization. C. difficile isolates from patients with colonization were compared with isolates from incident CDI cases using core genome multi-locus sequence typing to determine whether onwards transmission had occurred.Results: CDC was present in 108 of 2211 admissions (4.9%), whereas colonization with a toxigenic strain (toxigenic Clostridoides difficile colonization [tCDC]) was present in 68 of 2211 admissions (3.1%). Among these 108 patients with colonization, diverse PCR ribotypes were found and no 'hypervirulent' PCR ribotype 027 (RT027) was detected (95% CI, 0-0.028). None of the patients with colonization developed CDI during admission (0/49; 95% CI, 0-0.073) or 1-year follow-up (0/38; 95% CI, 0-0.93). Core genome multi-locus sequence typing identified six clusters with genetically related isolates from patients with tCDC and CDI; however, in these clusters, only one possible transmission event from a patient with tCDC to a patient with CDI was identified based on epidemiological data.Conclusion: In this endemic setting with a low prevalence of 'hypervirulent' strains, screening for CDC at admission did not detect any patients with CDC who progressed to symptomatic CDI and detected only one possible transmission event from a patient with colonization to a patient with CDI. Thus, screening for CDC at admission is not useful in this setting. Monique J.T. Crobach, Clin Microbiol Infect 2023;29:891 & COPY; 2023 The Authors. Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/). Show less
Clostridioides difficile, the primary cause of nosocomial antibiotic-associated diarrhea, has a complex relationship with antibiotics. While the use of broad-spectrum antibiotics disrupts the gut... Show moreClostridioides difficile, the primary cause of nosocomial antibiotic-associated diarrhea, has a complex relationship with antibiotics. While the use of broad-spectrum antibiotics disrupts the gut microbiota and increases the risk of C. difficile infection (CDI), antibiotics are also the primary treatment for CDI. However, only a few antibiotics, including vancomycin, fidaxomicin, and rifaximin, are effective against CDI, and resistance to these antibiotics has emerged recently. In this study, we report the identification of two RT027 C. difficile clinical isolates (TGH35 and TGH64) obtained from symptomatic CDI-diagnosed patients in Tampa, Florida in 2016. These two strains showed an elevated minimum inhibitory concentration (MIC) of vancomycin (MIC = 4 mu g/mL, compared to the EUCAST breakpoint of 2 mu g/mL) and contained a vanR(Cd) 343A>G mutation resulting in a Thr115Ala substitution in the VanR(Cd) response regulator. This mutation was absent in the vancomycin-sensitive control epidemic strain RT027/R20291. TGH64 was also resistant to rifaximin (MIC >= 128 mu g/mL) and carried the previously reported Arg505Lys and Ile548Met mutations in RpoB. Furthermore, we report on the antimicrobial resistance (AMR) and genomic characterization of additional C. difficile isolates, including RT106/TGH120, RT017/TGH33, and RT017/TGH51, obtained from the same patient sample cohort representing the highly prevalent and regionally distributed C. difficile ribotypes worldwide. Considering that the VanR(Cd) Thr115Ala mutation was also independently reported in seven C. difficile clinical isolates from Texas and Israel in 2019, we recommend epidemiological surveillance to better understand the impact of this mutation on vancomycin resistance.IMPORTANCE The perpetually evolving antimicrobial resistance (AMR) of C. difficile is an important contributor to its epidemiology and is a grave concern to global public health. This exacerbates the challenge of treating the infections caused by this multidrug-resistant causative organism of potentially life-threatening diarrhea. Further, the novel resistance-determining factors can be transferred between different strains and species of bacteria and cause the spread of AMR in clinical, environmental, and community settings. In this study, we have identified a mutation (vanR(Cd) 343A>G) that causes a Thr115Ala substitution and is linked to an increased MIC of vancomycin in clinical isolates of C. difficile obtained from Florida in 2016. Understanding the mechanisms of AMR, especially those of newly evolving strains, is essential to effectively guide antibiotic stewardship policies to combat antibiotic resistance as well as to discover novel therapeutic targets. Show less
Clostridioides difficile, the primary cause of nosocomial antibiotic-associated diarrhea, has a complex relationship with antibiotics. While the use of broad-spectrum antibiotics disrupts the gut... Show moreClostridioides difficile, the primary cause of nosocomial antibiotic-associated diarrhea, has a complex relationship with antibiotics. While the use of broad-spectrum antibiotics disrupts the gut microbiota and increases the risk of C. difficile infection (CDI), antibiotics are also the primary treatment for CDI. However, only a few antibiotics, including vancomycin, fidaxomicin, and rifaximin, are effective against CDI, and resistance to these antibiotics has emerged recently. In this study, we report the identification of two RT027 C. difficile clinical isolates (TGH35 and TGH64) obtained from symptomatic CDI-diagnosed patients in Tampa, Florida in 2016. These two strains showed an elevated minimum inhibitory concentration (MIC) of vancomycin (MIC = 4 μg/mL, compared to the EUCAST breakpoint of 2 μg/mL) and contained a vanRCd 343A>G mutation resulting in a Thr115Ala substitution in the VanRCd response regulator. This mutation was absent in the vancomycin-sensitive control epidemic strain RT027/R20291. TGH64 was also resistant to rifaximin (MIC ≥ 128 μg/mL) and carried the previously reported Arg505Lys and Ile548Met mutations in RpoB. Furthermore, we report on the antimicrobial resistance (AMR) and genomic characterization of additional C. difficile isolates, including RT106/TGH120, RT017/TGH33, and RT017/TGH51, obtained from the same patient sample cohort representing the highly prevalent and regionally distributed C. difficile ribotypes worldwide. Considering that the VanRCd Thr115Ala mutation was also independently reported in seven C. difficile clinical isolates from Texas and Israel in 2019, we recommend epidemiological surveillance to better understand the impact of this mutation on vancomycin resistance. Show less
Ducarmon, Q.R.; Bruggen, T. van der; Harmanus, C.; Sanders, I.M.J.G.; Daenen, L.G.M.; Fluit, A.C.; ... ; Smits, W.K. 2023
Objectives: We report a patient case of pseudomembranous colitis associated with a monotoxinproducing Clostridioides difficile belonging to the very rarely diagnosed polymerase chain reaction (PCR)... Show moreObjectives: We report a patient case of pseudomembranous colitis associated with a monotoxinproducing Clostridioides difficile belonging to the very rarely diagnosed polymerase chain reaction (PCR) ribotype (RT) 151. To understand why this isolate was not identified using a routine commercial test, we performed a genomic analysis of RT151. Methods: Illumina short-read sequencing was performed on n = 11 RT151s from various geographical regions to study their genomic characteristics and relatedness. Subsequently, we used PacBio circular consensus sequencing to determine the complete genome sequence of isolates belonging to cryptic clades CeI and C-II, which includes the patient isolate. Results: We found that 1) RT151s are polyphyletic with isolates falling into clades 1 and cryptic clades C eI and C-II; 2) RT151 contains both nontoxigenic and toxigenic isolates and 3) RT151 C-II isolates contained monotoxin pathogenicity loci. The isolate from our patient case report contains a novelpathogenicity loci insertion site, lacked tcdA and had a divergent tcdB sequence that might explain the failure of the diagnostic test. Discussion: This study shows that RT151 encompasses both typical and cryptic clades and provides conclusive evidence for C. difficile infection due to clade C-II isolates that was hitherto lacking. Vigilance towards C. difficile infection as a result of cryptic clade isolates is warranted. Quinten R. Ducarmon, Clin Microbiol Infect 2023;29:538.e1-538.e6 (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/). Show less
Ducarmon, Q.R.; Bruggen, T. van der; Harmanus, C.; Sanders, I.M.J.G.; Daenen, L.G.M.; Fluit, A.C.; ... ; Smits, W.K. 2023
ObjectivesWe report a patient case of pseudomembranous colitis associated with a monotoxin-producing Clostridioides difficile belonging to the very rarely diagnosed polymerase chain reaction (PCR)... Show moreObjectivesWe report a patient case of pseudomembranous colitis associated with a monotoxin-producing Clostridioides difficile belonging to the very rarely diagnosed polymerase chain reaction (PCR) ribotype (RT) 151. To understand why this isolate was not identified using a routine commercial test, we performed a genomic analysis of RT151.MethodsIllumina short-read sequencing was performed on n = 11 RT151s from various geographical regions to study their genomic characteristics and relatedness. Subsequently, we used PacBio circular consensus sequencing to determine the complete genome sequence of isolates belonging to cryptic clades C–I and C-II, which includes the patient isolate.ResultsWe found that 1) RT151s are polyphyletic with isolates falling into clades 1 and cryptic clades C–I and C-II; 2) RT151 contains both nontoxigenic and toxigenic isolates and 3) RT151 C-II isolates contained monotoxin pathogenicity loci. The isolate from our patient case report contains a novel-pathogenicity loci insertion site, lacked tcdA and had a divergent tcdB sequence that might explain the failure of the diagnostic test.DiscussionThis study shows that RT151 encompasses both typical and cryptic clades and provides conclusive evidence for C. difficile infection due to clade C-II isolates that was hitherto lacking. Vigilance towards C. difficile infection as a result of cryptic clade isolates is warranted. Show less
Clostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenic C. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human... Show moreClostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenic C. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human recurrent CDI. In this study, we evaluated the efficacy of metronidazole-resistant NTCD-E4 in preventing CDI facilitated by a range of antimicrobials in an in vitro human gut model. NTCD-E4 spores (at a dose of 10(7)) were instilled 7 days before a clinical ribotype (RT) 027 (at the same dose) strain (210). In separate experiments, four different antimicrobials were used to perturb gut microbiotas; bacterial populations and cytotoxin production were determined using viable counting and Vero cell cytotoxicity, respectively. RT027 and NTCD-E4 proliferated in the in vitro model when inoculated singly, with RT027 demonstrating high-level cytotoxin (3-5-log(10)-relative units) production. In experiments where the gut model was pre-inoculated with NTCD-E4, RT027 was remained quiescent and failed to produce cytotoxins. NTCD-E4 showed mutations in hsmA and a gene homologous to CD196-1331, previously linked to medium-dependent metronidazole resistance, but lacked other metronidazole resistance determinants. This study showed that RT027 was unable to elicit simulated infection in the presence of NTCD-E4 following stimulation by four different antimicrobials. These data complement animal and clinical studies in suggesting NTCD offer prophylactic potential in the management of human CDI. Show less
Clostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenicC. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human... Show moreClostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenicC. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human recurrentCDI. In this study, we evaluated the efficacy of metronidazole-resistant NTCD-E4 in preventingCDI facilitated by a range of antimicrobials in an in vitro human gut model. NTCD-E4 spores (ata dose of 107) were instilled 7 days before a clinical ribotype (RT) 027 (at the same dose) strain(210). In separate experiments, four different antimicrobials were used to perturb gut microbiotas;bacterial populations and cytotoxin production were determined using viable counting and Vero cellcytotoxicity, respectively. RT027 and NTCD-E4 proliferated in the in vitro model when inoculatedsingly, with RT027 demonstrating high-level cytotoxin (3-5-log10-relative units) production. Inexperiments where the gut model was pre-inoculated with NTCD-E4, RT027 was remained quiescentand failed to produce cytotoxins. NTCD-E4 showed mutations in hsmA and a gene homologous toCD196-1331, previously linked to medium-dependent metronidazole resistance, but lacked othermetronidazole resistance determinants. This study showed that RT027 was unable to elicit simulatedinfection in the presence of NTCD-E4 following stimulation by four different antimicrobials. Thesedata complement animal and clinical studies in suggesting NTCD offer prophylactic potential in themanagement of human CDI. Show less
Clostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenic C. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human... Show moreClostridioides difficile infection (CDI) remains a significant healthcare burden. Non-toxigenic C. difficile (NTCD) strains have shown a benefit in preventing porcine enteritis and in human recurrent CDI. In this study, we evaluated the efficacy of metronidazole-resistant NTCD-E4 in preventing CDI facilitated by a range of antimicrobials in an in vitro human gut model. NTCD-E4 spores (at a dose of 107) were instilled 7 days before a clinical ribotype (RT) 027 (at the same dose) strain (210). In separate experiments, four different antimicrobials were used to perturb gut microbiotas; bacterial populations and cytotoxin production were determined using viable counting and Vero cell cytotoxicity, respectively. RT027 and NTCD-E4 proliferated in the in vitro model when inoculated singly, with RT027 demonstrating high-level cytotoxin (3-5-log10-relative units) production. In experiments where the gut model was pre-inoculated with NTCD-E4, RT027 was remained quiescent and failed to produce cytotoxins. NTCD-E4 showed mutations in hsmA and a gene homologous to CD196-1331, previously linked to medium-dependent metronidazole resistance, but lacked other metronidazole resistance determinants. This study showed that RT027 was unable to elicit simulated infection in the presence of NTCD-E4 following stimulation by four different antimicrobials. These data complement animal and clinical studies in suggesting NTCD offer prophylactic potential in the management of human CDI. Show less
A subset of clinical isolates of Clostridioides difficile contains one or more plasmids and these plasmids can harbor virulence and antimicrobial resistance determinants. Despite their potential... Show moreA subset of clinical isolates of Clostridioides difficile contains one or more plasmids and these plasmids can harbor virulence and antimicrobial resistance determinants. Despite their potential importance, C. difficile plasmids remain poorly characterized. Here, we provide the complete genome sequence of a human clinical isolate that carries three high-copy number plasmids from three different plasmid families that are therefore compatible. For two of these, we identify a region capable of sustaining plasmid replication in C. difficile that is also compatible with the plasmid pCD630 that is found in many laboratory strains. Together, our data advance our understanding of C. difficile plasmid biology. Show less
The plasmid pCD-METRO confers metronidazole re-sistance in Clostridioides difficile. We showed high se-quence similarity among pCD-METRO plasmids from different isolates and identified pCD-METRO... Show moreThe plasmid pCD-METRO confers metronidazole re-sistance in Clostridioides difficile. We showed high se-quence similarity among pCD-METRO plasmids from different isolates and identified pCD-METRO and as-sociated metronidazole-resistant isolates in clinical and veterinary reservoirs in the Americas. We recommend using PCR or genomic assays to detect pCD-METRO in metronidazole-resistant C. difficile. Show less
Background: Clostridioides difficile is the most common causative agent of antibiotic-acquired diarrhea in hospitalized patients associated with substantial morbidity and mortality. The global... Show moreBackground: Clostridioides difficile is the most common causative agent of antibiotic-acquired diarrhea in hospitalized patients associated with substantial morbidity and mortality. The global epidemic of CDI (Clostridioides difficile infection) began in the early 20th century with the emergence of the hypervirulent and resistant ribotype 027 strains, and requires an urgent search for new therapeutic agents. Objective: The aim of this study is to investigate the antibacterial activity of the three essential oils isolated from spice herbs (wild oregano, garlic and black pepper) against C. difficile clinical isolates belonging to 6 different PCR ribotypes and their potential inhibitory effect on the biofilm production in in vitro conditions. Results: Wild oregano essential oil showed strong inhibitory activity in concentrations 0.02-1.25 mg/mL and bactericidal activity in concentrations from 0.08 to 10 mg/mL. Garlic essential oil was effective in the concentration range of 0.02-40 mg/mL, and 0.16 -> 40 mg/mL. MIC and MBC for black pepper oil ranged from 0.04 to 40 mg/mL, and 0.08 -> 40 mg/mL, respectively. All the tested oils reduced in vitro biofilm production, with the best activity of oregano oil. Conclusion: Essential oils of wild oregano, black pepper and garlic are candidates for adjunctive therapeutics in the treatment of CDI. Oregano oil should certainly be preferred due to the lack of selectivity of action in relation to the ribotype, the strength of the produced biofilm and/or antibiotic-susceptibility patterns.(c) 2022 Elsevier Ltd. All rights reserved. Show less
Background: During the COVID-19 pandemic, several factors, such as improved hand hygiene, social distancing, and restricted hospital referral, may have had an influence on the epidemiology of... Show moreBackground: During the COVID-19 pandemic, several factors, such as improved hand hygiene, social distancing, and restricted hospital referral, may have had an influence on the epidemiology of Clostridioides difficile infections (CDI). Methods: The annual CDI incidence rate of nine hospitals participating in the Dutch sentinel CI surveillance with complete data was compared between 2020 and the previous five surveillance years. Trends in characteristics of hos-pitalised CDI patients in 21-24 participating hospitals were compared between the first (March 13-May 12, 2020) or second Dutch COVID-19 wave (September 17, 2020-January 1, 2021) and the same calendar periods in 2015 through 2019. All analyses were adjusted for trend changes over time. Findings: The annual CDI incidence rate in 2020 was lower compared to previous years. During the second wave, the percentage of CDI patients with severe CDI was higher compared to earlier (25.8% in 2020 vs 17.9% in 2015-2019 (RR 1.6; 95%CI 1.1-2.3)). After adjustment for delayed C. difficile diagnostics (>= 8 days from start symptoms), the increase disappeared. Delayed C. difficile diagnostics was indeed more common during the second wave (RR 1.7; 95%CI 1.1-2.6), but only for community-onset CDI (CO-CDI). Interpretation: This study shows that a higher percentage of severe CDI cases was observed during the second COVID-19 wave. This may partially be caused by delayed diagnostics, potentially due to decreased visits to a physi-cian or restricted hospital referral for CO-CDI patients. Funding Dutch ministry of Health. Copyright (C) 2022 The Authors. Published by Elsevier Ltd. Show less
Aptekorz, M.; Sacha, K.; Gofron, Z.; Kabala, M.; Harmanus, C.; Kuijper, E.; Martirosian, G. 2022
Clostridioides difficile is an important health care-associated pathogen. The aim of this study was to analyze the antibiotic susceptibility of C. difficile isolates from feces of patients from 13... Show moreClostridioides difficile is an important health care-associated pathogen. The aim of this study was to analyze the antibiotic susceptibility of C. difficile isolates from feces of patients from 13 hospitals in Silesia, Poland. The incidence of CDI per 100.000 people in Silesia in 2018-2019 was higher than the average in Poland (39.3-38.7 vs. 30.2-29.5, respectively). The incidence doubled from 26.4 in 2020 to 55.1 in 2021. Two hundred and thirty stool samples tested positive for GDH (glutamate dehydrogenase) and toxins were cultured anaerobically for C. difficile. The isolates were characterized, typed, and tested for susceptibility to 11 antibiotics by E-test (EUCAST, 2021). The genes of toxins A/B and binary were detected by mPCR. Of 215 isolates, 166 (77.2%) were classified as RT 027 and 6 (2.8%) as related RT 176. Resistance to ciprofloxacin (96.7%), moxifloxacin (79.1%), imipenem (78.1%), penicillin (67%), and rifampicin (40.5%) was found. The ermB gene was detected in 79 (36.7%) strains. Multidrug resistance (MDR) was confirmed in 50 (23.3%) strains of RT 027 (94%). We concluded that a high prevalence of MDR among hypervirulent RT 027/176 C. difficile was found in the Silesian region of Poland, emphasizing the need to enhance regional infection control on CDI and antibiotic stewardships. Show less
Kachrimanidou, M.; Metallidis, S.; Tsachouridou, O.; Harmanus, C.; Lola, V.; Protonotariou, E.; ... ; Kuijper, E. 2022
Objectives: The epidemiology of Clostridioides difficile infection (CDI) has undergone many changes since the beginning of this century and continues to evolve based on recent studies. Here, we... Show moreObjectives: The epidemiology of Clostridioides difficile infection (CDI) has undergone many changes since the beginning of this century and continues to evolve based on recent studies. Here, we performed a molecular analysis of C. difficile isolates in northern Greece across 10 health-care facilities, spanning from 2016 to 2019. Methods: 221 C. difficile isolates were cultured from stool samples of hospitalized patients with diarrhea and screened by PCR for the presence of the toxin A (tcdA), toxin B (tcdB), the binary toxin (cdtA and cdtB) genes and the regulating gene of tcdC. PCR ribotyping of the cultured isolates was performed by a standardized protocol for capillary gel-based PCR ribotyping and an international database with well documented reference strains. Results: Thirty-five different PCR ribotypes were identified. The most common RTs identified were: 181 (36%, 80/221), 017 (10%, 21/221), 126 (9%, 19/221), 078 (4%, 9/221) and 012 (4%, 8/221). Notably, the predominant RT181, with toxin profile tcdA thorn tcdB thorn cdtA thorn cdtB thorn , was identified in seven out of ten participating hospitals. Conclusions: Multiple C. difficile ribotypes have been circulating in the northern Greece region with RTs 181 (closely related to 027), 017, 126 and 078 being predominant. (C) 2022 Elsevier Ltd. All rights reserved. Show less
Clostridioides difficile is the most common cause of antibiotic-associated gastrointestinal infections. Capillary electrophoresis (CE)-PCR ribotyping is currently the gold standard for C. difficile... Show moreClostridioides difficile is the most common cause of antibiotic-associated gastrointestinal infections. Capillary electrophoresis (CE)-PCR ribotyping is currently the gold standard for C. difficile typing but lacks the discriminatory power to study transmission and outbreaks in detail. New molecular methods have the capacity to differentiate better and provide standardized and interlaboratory exchangeable data. Using a well-characterized collection of diverse strains (N = 630; 100 unique ribotypes [RTs]), we compared the discriminatory power of core genome multilocus sequence typing (cgMLST) (SeqSphere and EnteroBase), whole-genome MLST (wgMLST) (EnteroBase), and single-nucleotide polymorphism (SNP) analysis. A unique cgMLST profile (more than six allele differences) was observed in 82 of 100 RTs, indicating that cgMLST could distinguish most, but not all, RTs. Application of cgMLST in two outbreak settings with RT078 and RT181 (known to have low intra-RT allele differences) showed no distinction between outbreak and nonoutbreak strains in contrast to wgMLST and SNP analysis. We conclude that cgMLST has the potential to be an alternative to CE-PCR ribotyping. The method is reproducible, easy to standardize, and offers higher discrimination. However, adjusted cutoff thresholds and epidemiological data are necessary to recognize outbreaks of some specific RTs. We propose to use an allelic threshold of three alleles to identify outbreaks. Show less
Kabala, M.; Gofron, Z.; Aptekorz, M.; Burdynowski, K.; Harmanus, C.; Kuijper, E.; Martirosian, G. 2022
116 environmental samples from a 504 bed clinical hospital obtained in 2017/19 were inoculated into C diff Banana Broth (TM). Six C. difficile and 12 C. pefringens strains were isolated. Antibiotic... Show more116 environmental samples from a 504 bed clinical hospital obtained in 2017/19 were inoculated into C diff Banana Broth (TM). Six C. difficile and 12 C. pefringens strains were isolated. Antibiotic-resistant Clostridium spp. dominated in hospital environment. To determine Clostridium spp. in hospital environment suitable medium like C diff Banana Broth (TM) should be used. (C) 2021 Published by Elsevier Ltd. Show less
Background: Until recently, metronidazole was the first-Line treatment for Clostridioides difficile infection and it is still commonly used. Though resistance has been reported due to the plasmid... Show moreBackground: Until recently, metronidazole was the first-Line treatment for Clostridioides difficile infection and it is still commonly used. Though resistance has been reported due to the plasmid pCD-METRO, this does not explain all cases.Objectives: To identify factors that contribute to plasmid-independent metronidazole resistance of C. difficile.Methods: Here, we investigate resistance to metronidazole in a collection of clinical isolates of C. difficile using a combination of antimicrobial susceptibility testing on different solid agar media and WGS of selected isolates.Results: We find that nearly all isolates demonstrate a haem-dependent increase in the MIC of metronidazole, which in some cases Leads to isolates qualifying as resistant (MIC >2 mg/L). Moreover, we find an SNP in the haem-responsive gene hsmA, which defines a metronidazole-resistant Lineage of PCR ribotype 010/MLST ST15 isolates that also includes pCD-METRO-containing strains.Conclusions: Our data demonstrate that haem is crucial for medium-dependent metronidazole resistance in C. difficile. Show less
Kabala, M.; Gofron, Z.; Aptekorz, M.; Sacha, K.; Harmanus, C.; Kuijper, E.; Martirosian, G. 2021
Objective: The aim of this study was Clostridioides difficile outbreak investigation due to the emergence of rifampicin resistant ribotype 027 (RT 027) fecal isolates from patients of Polish... Show moreObjective: The aim of this study was Clostridioides difficile outbreak investigation due to the emergence of rifampicin resistant ribotype 027 (RT 027) fecal isolates from patients of Polish tertiary care hospital between X. 2017 and II. 2018 using multilocus variable tandem repeat analysis (MLVA).Materials and Methods: Twenty-nine C. difficile fecal isolates from patients of tertiary care hospital in Southern Poland were ribotyped and analyzed by MLVA. Multiplex PCR (mPCR) for genes encoding GDH (gluD), toxins A (tcdA)/ B (tcdB), 16S rDNA and binary toxin genes (ctdA and ctdB) was performed. The antibiotic susceptibility profile was determined by E-test.Results: The A, B and binary toxins encoding genes were detected in all 29 C. difficile strains which were sensitive to metronidazole, vancomycin and were resistant to erythromycin, clindamycin, and moxifloxacin; resistance to imipenem demonstrated 97%, to rifampicin - 45% isolates. C. difficile strains could be grouped by MLVA into 5 distinct clusters, and the largest cluster II contains 16 strains. The comparison of rifampicin GM MIC of cluster II (n=16 strains) with all others (n=13) showed that strains from clusters I, III, IV and V possessed significantly (p <0.005) higher GM MIC and were more resistant to rifampicin.Conclusion: MLVA analysis proved transmission and recognized outbreak due to multidrugresistant RT 027 C. difficile among patients of tertiary care hospital in Southern Poland. The reason for this is probably the widespread occurrence of spores in the hospital environment, which includes, among others, neglect of hygienic procedures and epidemic supervision. High resistance to imipenem (97%) and to rifampicin (45%) among C. difficile RT 027 Silesian isolates is threatening and requires further studies to elucidate this phenomenon. Show less
