Thammanichanond Duangtawan, Kunakorn Mongkol, Settaudom Chavachol, Khupulsup Kalayanee
Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Asian Pac J Allergy Immunol. 2002 Jun;20(2):135-7.
In endemic areas of hepatitis B virus (HBV) infection, perinatal transmission from asymptomatic HBsAg carrier mothers to infants plays a major role in the transmission of HBV. HBeAg indicates a high level of viral replication and infectivity. Most of the infants born to HBeAg positive mothers become carriers. Prenatal screening of HBsAg would identify infected mothers and thus allow preventive administration of immunoglobulin and immunization to the newborns. Reversed passive hemagglutination assay (RPHA) is commonly used in Thailand for HBsAg screening. However this method has low sensitivity and gives false negative results. Therefore, infants born to HBsAg false negative mothers would not receive proper immunization. This study reveals the rate of false negative results for HBsAg by RPHA in high infectivity sera. Of 985 sera which were HBsAg positive by ELISA, 70 (7.1%) were negative for HBsAg by RPHA. Of these 70 false negative sera, 7 (10%) were HBeAg positive. Our results indicate that RPHA is a less sensitive method for detection of HBsAg than ELISA. RPHA can give false negative results even in sera with high HBV infectivity. Therefore, RPHA should be replaced by EIA for prenatal HBsAg screening or any other screening for HBV infection whenever possible.
在乙型肝炎病毒（HBV）感染的流行地区，无症状HBsAg携带者母亲将HBV围产期传播给婴儿是HBV传播的主要途径。HBeAg表明病毒复制水平高且具有传染性。大多数HBeAg阳性母亲所生的婴儿会成为携带者。对HBsAg进行产前筛查可识别受感染的母亲，从而能对新生儿预防性给予免疫球蛋白和进行免疫接种。反向被动血凝试验（RPHA）在泰国常用于HBsAg筛查。然而，该方法灵敏度低，会出现假阴性结果。因此，HBsAg检测结果为假阴性的母亲所生的婴儿无法得到适当的免疫接种。本研究揭示了RPHA在高传染性血清中检测HBsAg时的假阴性率。在985份ELISA检测HBsAg呈阳性的血清中，有70份（7.1%）RPHA检测HBsAg呈阴性。在这70份假阴性血清中，有7份（10%）HBeAg呈阳性。我们的结果表明，与ELISA相比，RPHA检测HBsAg的灵敏度较低。即使在HBV传染性高的血清中，RPHA也可能给出假阴性结果。因此，应尽可能用酶免疫测定法（EIA）取代RPHA进行产前HBsAg筛查或任何其他HBV感染筛查。
