Varshney Jyotika B, Very Katherine J, Williams Jen L, Hegarty John P, Stewart David B, Lumadue Jeanne, Venkitanarayanan Kumar, Jayarao Bhushan M
1 Department of Veterinary and Biomedical Sciences, Penn State Animal Diagnostic Laboratory, The Pennsylvania State University , University Park, Pennsylvania.
Foodborne Pathog Dis. 2014 Oct;11(10):822-9. doi: 10.1089/fpd.2014.1790.
A study was conducted to determine the prevalence of Clostridium difficile and characterize C. difficile isolates from human stool and retail grocery meat samples. Human stool samples (n=317) were obtained from a clinical laboratory and meat samples (n=303) were collected from 8 retail grocery stores from October 2011 through September 2012 from Centre County of Pennsylvania and were examined for C. difficile. C. difficile was isolated from 16.7% of stool samples (n=317) and 6.9%, 11.5%, 14.5%, and 7.8% of beef (n=72), pork (n=78), turkey (n=76), and chicken (n=77) samples, respectively. Six different toxin gene profiles were detected in all human and meat isolates of C. difficile based on the presence or absence of toxin genes tcdA, tcdB, and cdtA and cdtB. Interestingly, 75.6% of the human C. difficile isolates lacked any deletion in the tcdC gene (139-bp), whereas a 39-bp deletion was observed in 61.3% of the C. difficile strains isolated from meat samples. C. difficile from meat samples were more susceptible to clindamycin, moxifloxacin, vancomycin, and metronidazole than C. difficile isolates from human samples. Twenty-five different ribotypes were identified in human and meat C. difficile isolates. In conclusion, significant genotypic and phenotypic differences were observed between human and meat isolates of C. difficile; however, a few C. difficile isolates from meat-in particular ribotypes 078, PA01, PA05, PA16, and PA22 with unique profiles (toxin gene, tcdC gene size and antimicrobial resistance profiles)-were similar to human C. difficile isolates.
开展了一项研究，以确定艰难梭菌的流行情况，并对从人类粪便和零售杂货店肉类样本中分离出的艰难梭菌进行特征分析。从一家临床实验室获取了人类粪便样本（n = 317），并于2011年10月至2012年9月从宾夕法尼亚州中心县的8家零售杂货店收集了肉类样本（n = 303），检测其中的艰难梭菌。在16.7%的粪便样本（n = 317）以及分别在6.9%、11.5%、14.5%和7.8%的牛肉（n = 72）、猪肉（n = 78）、火鸡（n = 76）和鸡肉（n = 77）样本中分离出了艰难梭菌。基于毒素基因tcdA、tcdB以及cdtA和cdtB的有无，在所有人类和肉类来源的艰难梭菌分离株中检测到六种不同的毒素基因谱。有趣的是，75.6%的人类艰难梭菌分离株的tcdC基因（139 bp）没有任何缺失，而在从肉类样本中分离出的61.3%的艰难梭菌菌株中观察到有39 bp的缺失。与从人类样本中分离出的艰难梭菌相比，从肉类样本中分离出的艰难梭菌对克林霉素、莫西沙星、万古霉素和甲硝唑更敏感。在人类和肉类来源的艰难梭菌分离株中鉴定出25种不同的核糖型。总之，在人类和肉类来源的艰难梭菌分离株之间观察到了显著的基因型和表型差异；然而，一些来自肉类的艰难梭菌分离株——特别是核糖型078、PA01、PA05、PA16和PA22，具有独特的特征（毒素基因、tcdC基因大小和抗菌药物耐药谱）——与人类艰难梭菌分离株相似。
