Mekonen Endale T, Gerding Dale N, Sambol Susan P, Pottinger Jean M, Pulvirenti Joseph J, Marsh Dayle, Kocka Frank E, Johnson Stuart
Department of Medicine, Chicago Healthcare System, Northwestern University Medical School, Illinois, USA.
Infect Control Hosp Epidemiol. 2002 Nov;23(11):648-52. doi: 10.1086/501988.
To determine the epidemiology and relatedness of Clostridium difficile isolates in two geographically separated hospitals in a large metropolitan area, each with unique patients and personneL DESIGN: Observational descriptive molecular epidemiology of clinical C. difficile isolates.
Two tertiary-care hospitals in Chicago.
Consecutive C. difficile isolates from the clinical laboratory of a Veterans Affairs hospital during a 13-month period were typed by restriction endonuclease analysis (REA). During an overlapping 3-month period, stool specimens that tested positive for C. difficile toxin from patients at a nearby county hospital were cultured and the recovered isolates typed by the same method.
Nineteen (68%) of 28 nosocomial isolates at the smaller, Veterans Affairs hospital belonged to REA group K. Within this group of closely related strains, 9 distinct REA types were recognized. Twenty-one (72%) of 29 nosocomial isolates at the larger, county hospital also belonged to group K. However, the predominant REA types within group K differed markedly at each institution.
These findings demonstrate a high degree of similarity among nosocomial C. difficile strains from different hospitals in the same city and suggest the possibility of an extended outbreak of a prototype group K strain with subsequent genetic drift at the two different institutions.
确定在一个大都市区两所地理位置相隔的医院中艰难梭菌分离株的流行病学特征及相关性，两所医院各有独特的患者群体和工作人员。设计：对临床艰难梭菌分离株进行观察性描述性分子流行病学研究。
芝加哥的两所三级医疗医院。
对一家退伍军人事务医院临床实验室在13个月期间连续获得的艰难梭菌分离株进行限制性内切酶分析（REA）分型。在重叠的3个月期间，对附近县医院患者艰难梭菌毒素检测呈阳性的粪便标本进行培养，并对分离出的菌株采用相同方法分型。
在规模较小的退伍军人事务医院的28株医院感染分离株中，19株（68%）属于REA K组。在这一组密切相关的菌株中，识别出9种不同的REA型。在规模较大的县医院的29株医院感染分离株中，21株（72%）也属于K组。然而，K组内主要的REA型在每家机构明显不同。
这些发现表明，同一城市不同医院的医院感染艰难梭菌菌株具有高度相似性，并提示在这两家不同机构可能出现了一种原型K组菌株的大范围暴发以及随后的基因漂移。
