两种蛋白变性剂检测巨细胞病毒IgG抗体亲和指数对孕期原发感染诊断的探讨

Value of human cytomegalovirus IgG avidity index measured with two protein denaturing agents for the diagnosis of primary infection during pregnancy

目的探讨测定巨细胞病毒IgG抗体(CMV蛳IgG)亲和指数(AI)的方法对诊断孕期巨细胞病毒(CMV)原发性感染的可行性。方法以35mmol/L二乙胺和8mol/L脲素作为温和蛋白变性剂,采用间接ELISA方法检测CMV蛳IgGAI。结果检测111份血清标本,其中68例为CMV既往感染,43例为CMV近期原发或近期再感染。CMV蛳IgM阳性、CMV蛳IgGAI<45%作为近期原发感染;AI>55%作为既往感染。脲素和二乙胺方法的敏感性分别为50%和64.3%,特异性分别为97.1%、91.2%。结论用35mmol/L二乙胺洗脱一次10min的简易快速的方法检测CMV蛳IgGAI是可行的。CMV蛳IgGAI和CMV蛳IgM联合检测可能是目前用血清学方法区分近期原发与既往感染的较好方法之一。

Objective To investigate the preferrable method for determination of cytomegalovirus immunoglobulin G avidity index （ CMV-IgG AI ）as an effective diagnostic tool to distinguish primary CMV infection from past infection in pregnant women, Methods The measurement of CMV-IgG AI was tested by standard indirect ELISA using 35mmol/L Diethyl amine（DEA） and 8mol/L urea（urea） solution as wild protein denaturing agents. Results Sera from 68 cases with past CMV infection, 43 cases with acute re-infection or primary infection were studied. The CMV-IgG AI less than 45%,was defined as resent primary CMV infection. The CMV-IgG AI higher than 55% was defined as past CMV infection. The sensitivity and specificity of 8mmol/L urea and 35mmol/L DEA were 50% and 64.3% ;97.1% and 91.2% respectively.Conclusions Using 35mmol/L Diethyl amine solution and washing once for 10 min is found to be suitable for CMV-IgG AI determination. At present the combination of CMV-IgG AI and CMV-IgM assay seems to be a powerful serological tool to differentiate primary from past CMV infection.