Fetal damage following cytomegalovirus (CMV) intrauterine infection is mostly linked to primary infection.To differentiate primary infection from nonprimary infection, immunoglobulin M (IgM) tests are not reliable enough, and measurement of the IgG avidity appears to be the method that is the most widely used at present. In the present study the performance of the Vidas (bioMérieux) avidity assay was compared with that of a new enzyme immunoassay based on the use of a recombinant CMV glycoprotein B protein (Biotest).Human cytomegalovirus (CMV) is the most common cause of viral intrauterine infection. Symptomatic infection and fetal damage are mostly due to maternal primary infections. It is therefore important to differentiate primary from recurrent or persistent CMV infection in pregnant females. Serological diagnosis is easy in cases of seroconversion, but the discovery of immunoglobulin M (IgM) antibodies in the first serum sample obtained during pregnancy does not allow the diagnosis of a recent CMV primary infection. CMV-specific IgM antibodies can persist for months after primary infection (7) or reappear during recurrences (13). In some cases, specific IgM may also be due to a heterotypical immune response caused by an intercurrent infection (11,12). No "gold standard" assay and no reference test exist for the detection of primary CMV infection. Different approaches (microneutralization, Western blotting, or avidity assays) were developed to differentiate between recent and past CMV infection (2,4,5,8,9). Avidity assays for distinguishing CMV primary infection (with low-avidity IgG antibody) from CMV secondary infection (with high-avidity IgG antibody) are the most widely used techniques (2,6,10,14). More recently, an enzyme immunoassay (EIA) based on the determination of the IgG antibody response to the CMV glycoprotein B (gB) was developed for disitnguishing CMV primary or past infection (Biotest, Dreieich, Germany). Indeed, the anti-CMV gB response occurs 50 to 100 days after primary infection, so the absence of anti-gB IgG is suggestive of a recent infection.The aim of this study was to compare the performance of the commercially available Vidas IgG avidity assay (bioMérieux, Marcy l'Etoile, France) with an EIA based on the use of a recombinant CMV glycoprotein B (gB) protein (gB-EIA; Biotest). The combination of these two methods based on different approaches appears to be a simple system that can be used to improve serological diagnosis and to avoid unnecessary amniocentesis. MATERIALS AND METHODSCMV-specific IgG and IgM serology. All serum specimens were tested for CMV-specific IgG and IgM by microparticle EIAs (Axsym; Abbott Diagnostics, Wiesbaden-Delkenheim, Germany). For the IgM test, the procedure and the interpretation were as recommended by the manufacturer. The result was negative when the index value was Յ0.399, equivocal when the index value was Ͼ0.400 and Յ0.499, and positive when the index value was Ն0.500. For the IgG test we added a grey area to the manufacturer's recommendations. The ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.