Detection of primary CMV infection in Sudanese pregnant women by IgG avidity test

Abstract

ObjectiveTo diagnose primary cytomegalovirus (CMV) infection in pregnant women by determining CMV immunoglobulin G (IgG) avidity index. MethodsNinety pregnant women with an average age of 23 years were studied. Their demographic data were obtained along with blood samples. The anti-CMV immunoglobulin M (IgM) antibodies were determined on fully automated immuoanalyzer, while the CMV IgG avidity testing was carried out using avidity ELISA assay. ResultsAmong the pregnant women, 15.6% were in the first trimester, 30.0% in the second, and 54.4% in the third trimesters. Besides, 40.0% had chronic disease, while the other 60.0% did not. Anti-CMV IgM antibodies and CMV IgG avidity test showed that 1.1% of the pregnant women were CMV IgM positive and 98.9% were CMV IgG positive, respectively. The avidity test revealed the presence of low avidity of CMV IgG antibodies in 1.1% cases while 98.9% cases exhibited high avidity of CMV IgG antibodies. ConclusionsCMV IgG avidity test was important to distinguish between CMV recent and past infection rather than relying on IgG and IgM only, and IgM is not always indicative for recent or primary CMV infection.