POLYMERASE CHAIN-REACTION FOR PRENATAL-DIAGNOSIS OF CONGENITAL HUMAN CYTOMEGALOVIRUS-INFECTION

The reliability of the polymerase chain reaction (PCR) for prenatal di agnosis of human cytomegalovirus (HCMV) infection was determined by re trospective testing of 35 amniotic fluids identified previously as pos itive or negative for HCMV by virus isolation. Amniocentesis was perfo rmed in 26 pregnant women with primary HCMV infection at 14-36 weeks g estation, 3-21 weeks after maternal infection. Blood samples were obta ined from 20 fetuses for IgM determination and/or virus isolation. Amn iotic fluid culture led to antenatal diagnosis of HCMV in 9 of the 13 infected fetuses (sensitivity 69.2%) with one case diagnosed at a seco nd sampling. PCR was able to detect one additional infected fetus (10/ 13, sensitivity 76.9%). Nested PCR did not increase sensitivity of pre natal diagnosis. Three cases were not diagnosed by all the techniques employed. The specificity of virus isolation from and DNA detection by PCR in amniotic fluid was 100%. The negative predictive value for vir us isolation from amniotic fluid was 76.5% and for DNA detection by PC R 81.2%, whereas the positive predictive value was 100% for both techn iques. The results showed that neither approach can detect all cases o f congenital HCMV infection prenatally, and that the time interval bet ween maternal infection and sampling seems to be a major factor affect ing the reliability of prenatal diagnosis. (C) 1995 Wiley-Liss, Inc.