Audiological outcome of infants with congenital cytomegalovirus infection in a prospective study.

The aim of this study was to evaluate the audiological outcome of long-term follow-up of infants with asymptomatic congenital cytomegalovirus (CMV) infection as defined by the presence of CMV DNA in neonatal urine. 12599 pregnant women underwent screening for CMV IgG and IgM antibodies between 1996 and 2003. Eighteen infants with congenital CMV infection were identified. These infants underwent the newborn hearing screening test or auditory brainstem response test. Follow-up hearing assessments were performed with the auditory brainstem response and behavioral audiometry. The seropositive rate of CMV IgG antibody among the pregnant women was 75.3%, and the yearly seropositive rate decreased over the study period. One hundred and forty-six pregnant women were positive for IgM antibody, and 18 neonates (12.3%) had congenital CMV infection. Sensorineural hearing loss (SNHL) was detected in 4 (25%) of the 16 infants with asymptomatic infection and 1 (50%) of the 2 infants with symptomatic infection during the first 6 months of life. Two infants who passed the newborn hearing screening had a delayed-onset SNHL in follow-up examinations up to 4 years of age. Two had progressive hearing loss and 2 had improvement of hearing loss. Screening of pregnant women for CMV infection and repeated audiological examinations of infants are necessary because there are infants with delayed-onset SNHL or improved SNHL caused by asymptomatic congenital CMV infection.