Caprioli A, Falbo V, Ruggeri F M, Minelli F, Orskov I, Donelli G
Laboratorio di Ultrastructure, Istituto Superiore di Sanità, Rome, Italy.
J Clin Microbiol. 1989 Apr;27(4):758-61. doi: 10.1128/jcm.27.4.758-761.1989.
We examined the relationship between serotype and cytotoxic necrotizing factor (CNF) production in 123 hemolytic strains of Escherichia coli isolated from both stools and extraintestinal infections. Of 76 strains producing both hemolysin (Hly) and CNF, 66 (87%) belonged to one of six serogroups (O2, O4, O6, O22, O75, and O83). In contrast, 47 E. coli strains producing Hly only belonged to 21 different O serogroups, and only 2 of these (O6 and O18ac) were widely represented. Generally, CNF-positive and CNF-negative hemolytic isolates were assigned to different O serogroups, with the exception of O6, often present in both categories of isolates. Serogroups O4 and O18ac were significantly more prevalent among strains from extraintestinal infections than among those from stools. In contrast, the Hly-positive, CNF-negative isolates, belonging to numerous less common serogroups, were hardly ever isolated from extraintestinal infections. Serological typing further confirmed that hemolytic isolates of E. coli may grossly be divided into two main populations on the basis of the ability to produce CNF. Examination of hemolytic E. coli for this property may also be useful in achieving a more detailed characterization of pathogenic clones.
我们研究了从粪便和肠外感染中分离出的123株溶血性大肠杆菌菌株的血清型与细胞毒性坏死因子（CNF）产生之间的关系。在76株同时产生溶血素（Hly）和CNF的菌株中，66株（87%）属于六个血清群之一（O2、O4、O6、O22、O75和O83）。相比之下，仅产生Hly的47株大肠杆菌菌株属于21个不同的O血清群，其中只有2个（O6和O18ac）有广泛的代表性。一般来说，CNF阳性和CNF阴性的溶血性分离株被归入不同的O血清群，但O6除外，它在两类分离株中都经常出现。血清群O4和O18ac在肠外感染菌株中比在粪便菌株中明显更普遍。相反，属于众多不太常见血清群的Hly阳性、CNF阴性分离株很少从肠外感染中分离出来。血清学分型进一步证实，大肠杆菌的溶血性分离株可根据产生CNF的能力大致分为两个主要群体。检测溶血性大肠杆菌的这一特性也可能有助于更详细地鉴定致病克隆。
