Clostridium difficile is a Gram positive rod-shaped bacterium that produces two major toxins, A and B. The detection of the organism and its toxins has been widely carried out using specialized Enzyme-Linked Immunosor...Clostridium difficile is a Gram positive rod-shaped bacterium that produces two major toxins, A and B. The detection of the organism and its toxins has been widely carried out using specialized Enzyme-Linked Immunosorbent Assay (ELISA) kits;however these generally have been unsuccessful in identifying all Clostridium difficile positive samples. In this study, fifteen clinically symptomatic patients from three of the five major regional hospitals in Trinidad were investigated for Clostridium difficile infections. Stool samples were assessed by ELISA and cultured isolates were characterized using agar dilution antibiotic sensitivity assays, conventional Polymerase Chain Reaction (PCR), DNA sequencing and phylogenetic analysis of toxin A and B genes. All 15 patient stool samples and isolates were positive for toxigenic Clostridium difficile via ELISA and PCR respectively. All isolates were positive for the housekeeping tpi and Toxin B genes by PCR but only three of these were positive for the Toxin A gene. The Toxin B gene sequences showed 100% similarity levels among isolates while the Toxin A gene sequences showed 99% similarity among isolates. Phylogenetic analysis showed that the strains isolated in Trinidad most likely belonged to the same strain/group. Agar dilution sensitivity tests showed highest susceptibility to Pipercillin/Tazobactam and Meropenem (87%) and the highest resistance was seen with Cefotaxime in 93%. These results indicate that similar virulent strains of C. difficile are present in the Trinidad population and that pathogenic strains are more likely to be susceptible to Pipercillin/Tazobactam and Meropenem.展开更多
Objectives:Clostridium difficile is the major cause of infectious diarrhoea in humans after antimicrobial treatment.Clostridium difficile has been isolated from food animals and meat.The main purpose of this study was...Objectives:Clostridium difficile is the major cause of infectious diarrhoea in humans after antimicrobial treatment.Clostridium difficile has been isolated from food animals and meat.The main purpose of this study was to characterize C.difficile isolated from retail lettuce and determine the antibiotic resistance using five common clinical-selected antibiotics(metronidazole,vancomycin,clindamycin,erythromycin,and cefotaxime).Materials and Methods:Lettuce samples(grown in California,Arkansas,and Louisiana)were purchased from retail stores.Results:Toxigenic C.difficile was isolated from 13.8 per cent(41/297)of the lettuce samples.Among the toxigenic isolates,only 82.9 per cent(34/41)produced toxin B,17.1 per cent(7/41)produced both toxin A and toxin B,and two of the Louisiana C.difficile isolates were identified as ribotype 027.Under the treatment of the five antibiotics,the virulence C.difficile isolates were identified as having antibiotic resistance to metronidazole,vancomycin,and erythromycin.Conclusion:The present study reports the highest prevalence of toxigenic C.difficile in US retail lettuce.The antibiotic resistance to metronidazole,vancomycin,and erythromycin of the isolated C.difficile from retail lettuces could lead to public health concerns.展开更多
文摘Clostridium difficile is a Gram positive rod-shaped bacterium that produces two major toxins, A and B. The detection of the organism and its toxins has been widely carried out using specialized Enzyme-Linked Immunosorbent Assay (ELISA) kits;however these generally have been unsuccessful in identifying all Clostridium difficile positive samples. In this study, fifteen clinically symptomatic patients from three of the five major regional hospitals in Trinidad were investigated for Clostridium difficile infections. Stool samples were assessed by ELISA and cultured isolates were characterized using agar dilution antibiotic sensitivity assays, conventional Polymerase Chain Reaction (PCR), DNA sequencing and phylogenetic analysis of toxin A and B genes. All 15 patient stool samples and isolates were positive for toxigenic Clostridium difficile via ELISA and PCR respectively. All isolates were positive for the housekeeping tpi and Toxin B genes by PCR but only three of these were positive for the Toxin A gene. The Toxin B gene sequences showed 100% similarity levels among isolates while the Toxin A gene sequences showed 99% similarity among isolates. Phylogenetic analysis showed that the strains isolated in Trinidad most likely belonged to the same strain/group. Agar dilution sensitivity tests showed highest susceptibility to Pipercillin/Tazobactam and Meropenem (87%) and the highest resistance was seen with Cefotaxime in 93%. These results indicate that similar virulent strains of C. difficile are present in the Trinidad population and that pathogenic strains are more likely to be susceptible to Pipercillin/Tazobactam and Meropenem.
基金the US Department of Agriculture National Institute of Food and Agriculture Multi-state Hatch project accession number 1000600。
文摘Objectives:Clostridium difficile is the major cause of infectious diarrhoea in humans after antimicrobial treatment.Clostridium difficile has been isolated from food animals and meat.The main purpose of this study was to characterize C.difficile isolated from retail lettuce and determine the antibiotic resistance using five common clinical-selected antibiotics(metronidazole,vancomycin,clindamycin,erythromycin,and cefotaxime).Materials and Methods:Lettuce samples(grown in California,Arkansas,and Louisiana)were purchased from retail stores.Results:Toxigenic C.difficile was isolated from 13.8 per cent(41/297)of the lettuce samples.Among the toxigenic isolates,only 82.9 per cent(34/41)produced toxin B,17.1 per cent(7/41)produced both toxin A and toxin B,and two of the Louisiana C.difficile isolates were identified as ribotype 027.Under the treatment of the five antibiotics,the virulence C.difficile isolates were identified as having antibiotic resistance to metronidazole,vancomycin,and erythromycin.Conclusion:The present study reports the highest prevalence of toxigenic C.difficile in US retail lettuce.The antibiotic resistance to metronidazole,vancomycin,and erythromycin of the isolated C.difficile from retail lettuces could lead to public health concerns.
