Kehl K S, Havens P, Behnke C E, Acheson D W
Department of Pathology, Medical College of Wisconsin, and Children's Hospital of Wisconsin, Milwaukee 53226, USA.
J Clin Microbiol. 1997 Aug;35(8):2051-4. doi: 10.1128/jcm.35.8.2051-2054.1997.
An enzyme-linked immunosorbent assay for the detection of Shiga toxins (Premier EHEC assay; Meridian Diagnostics, Inc.) was compared to conventional sorbitol-MacConkey culture for the recovery of enterohemorrhagic Escherichia coli. A total of 74 enteric pathogens, including 8 E. coli O157:H7 isolates, were recovered from 974 stool specimens. Two of these specimens were not tested by Premier assaying due to insufficient sample and are not considered in the data analysis. The Premier EHEC assay detected the 6 evaluable specimens which were culture positive for E. coli O157:H7 and identified an additional 10 specimens as containing Shiga toxin. Seven isolates were recovered from these 10 specimens by an immunoblot assay and were confirmed as toxin producers by a cytotoxin assay. Of these seven, four isolates were serotype O157:H7, one was O26:NM, one was O6:H-, and one was O untypeable:H untypeable. Three specimens contained Shiga toxin by both EHEC immunoassaying and cytotoxin testing; however, no cytotoxin-producing E. coli could be recovered. The sorbitol-MacConkey method had a sensitivity and a specificity of 60 and 100%, respectively, while the Premier EHEC assay had a sensitivity and a specificity of 100 and 99.7%, respectively, for E. coli O157:H7 only. The Premier EHEC assay also detected an additional 20% Shiga toxin-producing E. coli (STEC) that were non-O157:H7. Thus, the Premier EHEC assay is a sensitive and specific method for the detection of all STEC isolates. Routine use would improve the detection of E. coli O157:H7 and allow for determination of the true incidence of STEC other than O157:H7. The presence of blood in the stool and/or the ages of the patients were poor predictors of the presence of STEC. Criteria need to be determined which would allow for the cost-effective incorporation of this assay into the routine screen for enteric pathogens in high-risk individuals, especially children.
将用于检测志贺毒素的酶联免疫吸附测定法（Premier EHEC测定法；Meridian诊断公司）与传统的山梨醇-麦康凯培养法进行比较，以回收肠出血性大肠杆菌。从974份粪便标本中总共分离出74种肠道病原体，其中包括8株大肠杆菌O157:H7分离株。由于样本不足，其中两份标本未进行Premier检测，数据分析中未考虑这两份标本。Premier EHEC测定法检测出6份可评估标本，这些标本经培养后大肠杆菌O157:H7呈阳性，并另外鉴定出10份标本含有志贺毒素。通过免疫印迹法从这10份标本中分离出7株菌株，并通过细胞毒素测定法确认为毒素产生菌。在这7株菌株中，4株为血清型O157:H7，1株为O26:NM，1株为O6:H-，1株为无法分型的O:无法分型的H。3份标本通过EHEC免疫测定法和细胞毒素检测均含有志贺毒素；然而，未回收产细胞毒素的大肠杆菌。山梨醇-麦康凯方法对大肠杆菌O157:H7的敏感性和特异性分别为60%和100%，而Premier EHEC测定法对大肠杆菌O157:H7的敏感性和特异性分别为100%和99.7%。Premier EHEC测定法还检测出另外20%的非O157:H7产志贺毒素大肠杆菌（STEC）。因此，Premier EHEC测定法是检测所有STEC分离株的一种灵敏且特异的方法。常规使用将改善大肠杆菌O157:H7的检测，并有助于确定非O157:H7 STEC的真实发病率。粪便中是否有血和/或患者年龄对STEC的存在预测性较差。需要确定标准，以便能以具有成本效益的方式将该测定法纳入高危个体（尤其是儿童）肠道病原体的常规筛查中。
