Specific and non-specific serological markers in the screening for congenital CMV infection

IgM antibodies specific for cytomegalovirus (CMV) were demonstrated in 15 (2.6%) of 575 umbilical cord sera obtained from newborns in Kuwait. Some 93% and 50% of these CMV-IgM positive cord sera displayed markedly raised (more than normal mean +2 S.D.) content of total IgM and IgA respectively. In contrast, only 0.2 and 1.8% of the CMV-IgM negative cord sera had elevated total IgM and IgA, respectively. Rheumatoid factor (RF) was demonstrable, at concentrations of 30 IU/ml or more, in 67% of the CMV-IgM positive as compared with 3.2% of the CMV-IgM negative sera whereas interferon alpha was found in the serum of only one of these infants. These results indicate that raised total immunoglobulin, in particular IgM, concentrations and the detection of RF in cord blood are useful non-specific markers for the identification of congenital CMV infection.

Factors affecting the detection of cytomegalovirus in urine by sandwich enzyme immunoassays

Some factors influencing the detection of human cytomegalovirus (HCMV) in urine were investigated employing 2 enzyme-linked immunosorbent assays (ELISAs); one utilised anti-CMV DNA polymerase while the other anti-CMV mouse monoclonals as the detecting antibodies. The use of anti-CMV DNA polymerase was found to be superior in detecting HCMV in both urine and tissue culture fluids than anti-CMV monoclonals. Furthermore, alkaline phosphatase conjugates produced much lower background than did peroxidase conjugates. In reconstruction experiments, the extremes of pH in the urine clearly had an adverse effect on the detection rate of extracellular virus. pH correction of urines to neutrality improved the detection rate considerably. On the other hand, pH correction had little effect on the detection rate of intracellular HCMV in urine, although it was improved when specimens were subjected to repeated cycles of freeze-thawing, ultrasonication, and storage at 4 degrees C. It was concluded that, in addition to the factors investigated which all appear to affect virus detection rate, there may well be additional factors that interfere with CMV detection in the urine by ELISA particularly with intracellular virus.

Hepatitis B virus perinatal transmission among Arab women

One thousand five hundred and fifty-four Arab women were screened at delivery for the presence of hepatitis B virus (HBV) antigenaemia in their sera. Forty-five or 2.9% were found to be positive. Only three of 41 (7.3%) of these hepatitis B surface antigen-positive (HbsAg) mothers were found to be positive for the presence of hepatitis B e antigen (HBeAg), 27 (65.8%) had anti-HBe and the remaining 11 (26.8%) had neither HBeAg nor its corresponding antibody. These results, therefore, predicted a low rate of transmission of virus from mother to newborn. Follow-up for 4-13 months after delivery on 14 of these HBsAG-positive mothers and their infants indicated that in only one infant born to an HBeAg-positive mother did HBV antigenaemia develop. Another infant died from undetermined causes. Therefore, HBV perinatal transmission among Arabs, unlike that among populations in Southeast Asia, does not appear to contribute in an important way to the pool of carriers in this population.