Although Escherichia coli is the most frequently isolated microorganism in acute biliary tract infections with bacteremia, data regarding its virulence are limited. Information on cases of bacteremia in acute biliary tract infection in a retrospective study was collected from 2013 to 2015 at a tertiary care hospital in Japan. Factors related to the severity of infection were investigated, including patient background, phylogenetic typing, and virulence factors of E. coli, such as adhesion, invasion, toxins, and iron acquisition. In total, 72 E. coli strains were identified in 71 cases, most of which primarily belonged to the B2 phylogroup (68.1%). The presence of the iutA gene (77.3% in the non-severe group, 46.4% in the severe group, P = 0.011) and the ibeA gene (9.1% in the non-severe group, and 35.7% in the severe group, P = 0.012) was significantly associated with the severity of infection. Among the patient characteristics, diabetes mellitus with organ involvement and alkaline phosphatase were different in the severe and non-severe groups. We showed that bacteremic E. coli strains from acute biliary tract infections belonged to the virulent (B2) phylogroup. The prevalence of the iutA and ibeA genes between the two groups of bacteremia severity was significantly different.

中文翻译：

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重症和非重症细菌性急性胆道感染的大肠埃希菌分离株中iutA和ibeA基因的患病率明显不同

尽管大肠杆菌是急性胆道感染菌血症的最常见分离微生物，但有关其毒力的数据有限。一项回顾性研究收集了2013年至2015年间日本三级医院的急性胆道感染菌血症病例信息。调查了与感染严重程度相关的因素，包括患者背景，系统发育分型和大肠杆菌的毒力因子，例如黏附，侵袭，毒素和铁摄取。总共在71例病例中鉴定出72株大肠杆菌，其中大多数主要属于B2系统群（68.1％）。iutA基因的存在（非严重组为77.3％，严重组为46.4％，P = 0.011）和ibeA基因（非严重组为9.1％，严重组为35.7％，P = 0。012）与感染的严重程度显着相关。在患者特征中，重度和非重度组伴器官累及的糖尿病和碱性磷酸酶不同。我们表明急性胆道感染的细菌性大肠杆菌菌株属于强力（B2）系统族。两组菌血症严重程度之间iutA和ibeA基因的患病率显着不同。