Cytomegalovirus in peripheral blood leukocytes of infants with congenital or postnatal infection

Background. Cytomegalovirus (CMV) is the most frequent agent of viral infection in the fetus; it causes varying damage, particularly neurologic, which becomes evident at birth or in infancy in about 20% of infected individuals. Postnatal acquisition is usually asymptomatic and without sequelae. Laboratory diagnosis of congenital and postnatal infection is based on the demonstration of virus in urine. Objectives. To investigate the systemic spread of CMV in neonates with congenital or postnatal infection and to evaluate its significance in diag¬nosis and in monitoring anti-CMV treatments. Design. Quantitative determinations of infec¬tive CMV (viremia) and viral antigen pp65 (anti¬genemia) were performed on peripheral blood leukocytes (PBL) from the buffy coat of hepa¬rinized blood from children with a diagnosis of congenital (n = 19) or postnatal (n = 19) infection based on viral isolation from urine. Results. Antigen pp65 in PBL was detected particularly in children with symptomatic infection, both congenital (100%) and postnatal (79%; P > 0.05), and significantly less frequently (50%; P < 0.001) in those with asymptomatic infection. Viremia was observed less often but always in association with antigenemia. Both tests became negative within 6 months. Neither viral titer nor persistent positivity was related to clinical man¬ifestations. In the nine infants given anti-CMV therapy (ganciclovir and/or hyperimmune gam¬ma-globulins) an early suspension of treatment resulted in the appearance of antigenemia and/or viremia. Conclusions. Cytomegalovirus was detected in PBL mainly in the most severely affected chil¬dren. Monitoring antigenemia and viremia in CMV-infected infants is recommended to demon¬strate persistent systemic infection and to eval¬uate virologic results of treatment.