No abstract

A real-time PCR assay was developed to quantify human cytomegalovirus (HCMV) DNA in amniotic fluid (AF) samples collected from 30 pregnant women with primary HCMV infection as detected either from HCMV-immunoglobulin G (IgG) seroconversion or by the presence of HCMV-specific IgG and IgM associated with a low IgG avidity. Clinical information available for each case included ultrasonographic examination and fetal or newborn outcome. HCMV infection of fetuses or newborns was confirmed for the 30 studied cases. AF samples were subdivided into three groups. In group A (n ‫؍‬ 13), fetuses presented major ultrasound abnormalities, and pregnancy was terminated. In group B (n ‫؍‬ 13), fetuses had normal ultrasound findings, the pregnancy went to term, and the newborns were asymptomatic at birth. In group C (n ‫؍‬ 4), fetuses had no or minor ultrasonographic signs, and pregnancy was terminated. The HCMV DNA load values in AF samples were significantly higher in group A (median, 2.8 ؋ 10 5 genome equivalents [GE]/ml) than in group B (median, 8 ؋ 10 3 GE/ml) (P ‫؍‬ 0.014). Our findings suggest that HCMV load level in AF samples correlates with fetal clinical outcome but might also be dependent on other factors, such as the gestational age at the time of AF sampling and the time elapsed since maternal infection.Human cytomegalovirus (HCMV) is the most common cause of viral intrauterine infection in developed countries, affecting 0.5 to 2% of all live births (1,32,40). Although the possibility of severe symptomatic fetal infection following recurrent maternal infection has been reported (8), fetal damage is mostly related to primary maternal infection (16,38,39). In this case, the transmission of the virus to the fetus may occur in 20 to 50% of pregnancies (18,27,38). It has been reported that HCMV transmission rates increase with gestational age and that a major risk of transmission is observed for seroconversion occurring late in pregnancy (5).Congenitally infected infants are asymptomatic at birth in about 90% of cases, and for symptomatic infants, infection ranges from mild to severe disseminated life-threatening disease resulting in up to 20% perinatal mortality (9,16,22,28,31,37). Up to 90% of the surviving symptomatic newborns will exhibit psychomotor and perceptual sequelae such as sensorineural hearing loss, mental retardation, cerebral palsy, seizures, and visual defects (2). Additionally, 10% of the infants who are asymptomatic at birth will later develop complications, mainly neurodevelopmental defects and deafness (7,15,40).The diagnosis of maternal primary HCMV infection is based mostly on serological testing, including HCMV immunoglobulin G (IgG) seroconversion and the presence of specific HCMV IgG and IgM (35). Moreover, the direct detection of viral components, including pp65 antigenemia and DNAemia, can be helpful for acute infection diagnosis. Prenatal diagnosis of HCMV congenital infection relies on virus isolation from amniotic fluid (AF) and/or viral DNA detection by PCR in AF samples (4,12,24,25,36,42)...

Human cytomegalovirus (HCMV) is the most common cause of viral intrauterine infection and fetal damage largely due to maternal primary infection. Virological procedures which are able to detect HCMV fetal infection were evaluated. HCMV IgG antibodies were detected in 62.5% of the pregnant women and 1.47% had a primary infection. From March, 1992 to August, 1995, 29 seroconversions were observed, and in 64 other cases. HCMV IgM antibodies were detected in the first serological test. The mean IgG antibody avidity test (AI) was 31% for the 11 seroconversions tested and 74% in 32 cases where IgG and IgM HCMV antibodies were detected in the first serum. In the 29 HCMV seroconversions, 19 amniocentesis were carried out and 12 fetuses (41.4%) were infected in utero. In four amniotic fluids positive in culture and PCR, the fetus or newborns were infected and in one out of the two cordocentesis undertaken, hepatitis, anemia, and thrombocytopenia were noted. In four other cases, investigations seeking HCMV in amniotic fluid were negative whereas infants were infected at birth. Among the 64 cases with positive HCMV IgM and IgG antibodies detected in the first serological test, three fetuses were infected in utero, but no amniotic fluid was available in these cases. Amniotic fluids were studied in 39 cases, and HCMV detection by culture and PCR-hybridization was negative. HCMV DNA was detected in the maternal sera of five out of 21 pairs of seroconversions and in two cases on the first negative serum. The assay was also carried out on 50 of the 64 HCMV IgM positive sera. Two had detectable HCMV DNA.