志贺毒素产生型大肠杆菌通过 Stx-PCR 诊断：评估非 O157 血清型菌株的公共卫生风险。

Shiga toxin-producing Escherichia coli diagnosed by Stx PCR: assessing the public health risk of non-O157 strains.

机构信息

Surrey and Sussex Health Protection Team, Public Health England South East, Horsham, UK.

National Infection Service, Public Health England, London, UK.

出版信息

Eur J Public Health. 2021 Jul 13;31(3):576-582. doi: 10.1093/eurpub/ckaa232.

DOI:10.1093/eurpub/ckaa232

PMID:33411922

Abstract

BACKGROUND

The implementation by diagnostic laboratories in England of polymerase chain reaction (PCR) to screen faecal specimens for Shiga toxin-producing Escherichia coli (STEC) has resulted in a significant increase in notifications mainly due to non-O157 strains. The purpose of this study was to develop an approach to public health risk assessment that prioritizes follow-up to cases caused by haemolytic uraemic syndrome (HUS) associated E. coli (HUSEC) strains and minimizes unnecessary actions.

METHODS

Epidemiological and microbiological data were prospectively collected from 1 November 2013 to 31 March 2017 and used to compare three risk assessment approaches.

RESULTS

A history of HUS/bloody diarrhoea/age under 6 years and faecal specimens positive for stx-predicted HUSEC with a diagnostic accuracy of 84% (95% CI; 81-88%). STEC isolated by Gastrointestinal Bacteria Reference Unit (GBRU) and stx2 and eae positive predicted HUSEC with a diagnostic accuracy of 99% (95% CI; 98-100%). Risk assessment combining these two tests predicts the most efficient use of resources, predicting that 18% (97/552) of cases would be eligible for follow-up at some stage, 16% (86/552) following local stx PCR results, 1% (7/552) following GBRU results of stx2 and eae status and 0.7% (4/552) following whole-genome sequencing. Follow-up could be stopped in 78% (76/97) of these cases, 97% (74/76) following second stage risk assessment.

CONCLUSIONS

This three-stage risk assessment approach prioritizes follow-up to HUSEC and minimizes unnecessary public health actions. We developed it into the algorithm for public health actions included in the updated PHE Guidance for management of STEC published in August 2018.

摘要

背景

英国诊断实验室实施聚合酶链反应（PCR）筛选粪便标本中的产志贺毒素大肠杆菌（STEC），导致通知数量显著增加，主要是由于非 O157 菌株。本研究旨在开发一种公共卫生风险评估方法，该方法优先考虑对与溶血性尿毒综合征（HUS）相关的大肠杆菌（HUSEC）菌株引起的病例进行随访，并尽量减少不必要的行动。

方法

从 2013 年 11 月 1 日至 2017 年 3 月 31 日，前瞻性收集了流行病学和微生物学数据，并用于比较三种风险评估方法。

结果

HUS/血性腹泻/年龄<6 岁和粪便标本 stx-预测 HUSEC 阳性的病史，具有 84%（95%CI；81-88%）的诊断准确性。由胃肠道细菌参考单位（GBRU）分离的 STEC 和 stx2 和 eae 阳性预测 HUSEC，具有 99%（95%CI；98-100%）的诊断准确性。结合这两种检测方法的风险评估预测了资源的最有效利用，预测 18%（97/552）的病例将在某个阶段有资格进行随访，16%（86/552）的病例将根据当地 stx PCR 结果进行随访，1%（7/552）的病例将根据 GBRU 的 stx2 和 eae 状态进行随访，0.7%（4/552）的病例将根据全基因组测序进行随访。在这些病例中，78%（76/97）的病例可以停止随访，97%（74/76）的病例在进行第二阶段风险评估后可以停止随访。