...
首页> 外文期刊>Journal of Clinical Microbiology >Assessing the Public Health Risk of Shiga Toxin-Producing Escherichia coli by Use of a Rapid Diagnostic Screening Algorithm
【24h】

Assessing the Public Health Risk of Shiga Toxin-Producing Escherichia coli by Use of a Rapid Diagnostic Screening Algorithm

机译:

获取原文
获取原文并翻译 | 示例
           

摘要

Shiga toxin-producing Escherichia coli (STEC) is an enteropathogen of public health concern because of its ability to cause serious illness and outbreaks. In this prospective study, a diagnostic screening algorithm to categorize STEC infections into risk groups was evaluated. The algorithm consists of prescreening stool specimens with real-time PCR (qPCR) for the presence of stx genes. The qPCR-positive stool samples were cultured in enrichment broth and again screened for stx genes and additional virulence factors (escV, aggR, aat, bfpA) and O serogroups (O26, O103, O104, O111, O121, O145, O157). Also, PCR-guided culture was performed with sorbitol MacConkey agar (SMAC) and CHROMagar STEC medium. The presence of virulence factors and O serogroups was used for presumptive pathotype (PT) categorization in four PT groups. The potential risk for severe disease was categorized from high risk for PT group I to low risk for PT group III, whereas PT group IV consists of unconfirmed stx qPCR-positive samples. In total, 5,022 stool samples of patients with gastrointestinal symptoms were included. The qPCR detected stx genes in 1.8 of samples. Extensive screening for virulence factors and O serogroups was performed on 73 samples. After enrichment, the presence of stx genes was confirmed in 65 samples (89). By culture on selective media, STEC was isolated in 36 (26/73 samples). Threshold cycle (C-T) values for stx genes were significantly lower after enrichment compared to direct qPCR (P < 0.001). In total, 11 (15), 19 (26), 35 (48), and 8 (11) samples were categorized into PT groups I, II, III, and IV, respectively. Several virulence factors (stx(2), stx(2a), stx(2f), toxB, eae, efa1, cif, espA, tccP, espP, nleA and/or nleB, tir cluster) were associated with PT groups I and II, while others (stx(1), eaaA, mch cluster, ireA) were associated with PT group III. Furthermore, the number of virulence factors differed between PT groups (analysis of variance, P < 0.0001). In conclusion, a diagnostic algorithm enables fast discrimination of STEC infections associated with a high to moderate risk for severe disease (PT groups I and II) from less-virulent STEC (PT group III).

著录项

获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号