title: Molecular Characterization of Clostridium difficile Isolates from Human Subjects and the Environment.
abstract: Clostridium difficile is a spore-forming, gram-positive, anaerobic bacillus that can cause C. difficile infection (CDI). However, only a few studies on the prevalence and antibiotic resistance of C. difficile in healthy individuals in China have been reported. We employed a spore enrichment culture to screen for C. difficile in the stool samples of 3699 healthy Chinese individuals who were divided into 4 groups: infants younger than 2 years of age and living at home with their parents; children aged 1 to 8 years of age and attending three different kindergarten schools; community-dwelling healthy adult aged 23-60 years old; and healthcare workers aged 28-80 years old. The C. difficile isolates were analyzed for the presence of toxin genes and typed by PCR ribotyping and multilocus sequence typing (MLST). The minimum inhibitory concentration of 8 antimicrobial agents was determined for all of the isolates using the agar dilution method. The intestinal carriage rate in the healthy children was 13.6% and ranged from 0% to 21% depending on age. The carriage rates in the 1654 community-dwelling healthy adults and 348 healthcare workers were 5.5% and 6.3%, respectively. Among the isolates, 226 were toxigenic (225 tcdA+/tcdB+ and 1 tcdA+/tcdB+ ctdA+/ctdB+). Twenty-four ribotypes were found, with the dominant type accounting for 29.7% of the isolates. The toxigenic isolates were typed into 27 MLST genotypes. All of the strains were susceptible to vancomycin, metronidazole, fidaxomicin, and rifaximin. High resistance to levofloxacin and ciprofloxacin at rates of 39.8% and 98.3%, respectively, were observed. ST37 isolates were more resistant to levofloxacin than the other STs. The PCR ribotypes and sequence types from the healthy populations were similar to those from the adult patients.
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Tian-tian
authors.initials: TT
authors.lastname: Tian
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Jian-hong
authors.initials: JH
authors.lastname: Zhao
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Cui-xin
authors.initials: CX
authors.lastname: Qiang
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Zhi-rong
authors.initials: ZR
authors.lastname: Li
authors.affiliation: Health Care Department, Maternal and Child Health Care Center of Cangzhou, Cangzhou City, Hebei Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Kai-yue
authors.initials: KY
authors.lastname: Xu
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Qing-qing
authors.initials: QQ
authors.lastname: Ciu
authors.affiliation: Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang City, Hebei Province, China.
authors.forename: Ru-xin
authors.initials: RX
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016360:Clostridioides difficile / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D024881:Drug Resistance, Bacterial; D004761:Enterocolitis, Pseudomembranous / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D007422:Intestines / Q000382:microbiology*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D015995:Prevalence; D021521:Ribotyping; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents