Screening for congenital cytomegalovirus infection among preterm infants born before the 34th gestational week in Finland.

83 infants born before 34 weeks of gestation between 1989 and 1990 and cared for at a neonatal intensive care unit in Kuopio, Finland, were screened for congenital cytomegalovirus (CMV) infection, defined as a positive culture from the sample of urine taken on the first day after birth. Four infants were infected and excreted CMV in the urine. The overall incidence of CMV excretors was 4.8%. The incidence was 1/13 infants born before 28 weeks' gestation and 3/70 infants born between 28 and 34 weeks of gestation. The 4 CMV excretors were followed up for 12-25 months. Two children had normal psychomotor and mental development but exhibited decreasing head growth during follow-up. The other 2 developed severe psychomotor retardation, retinopathy of prematurity, chorioretinitis, and microcephaly. The long-term morbidity was associated not only with congenital CMV infection but to prematurity as well. The incidence of congenital CMV excretors in this preterm population seemed to be higher than reported previously among unselected live-born infants. Early diagnosis of congenital CMV infection would seem to be important in view of forthcoming new therapeutic regimes in the near future.