Neuro-imaging findings in infants with congenital cytomegalovirus infection: relation to trimester of infection.

BACKGROUND: Congenital cytomegalovirus (cCMV) infection early in pregnancy may result in major disabilities. Cerebral abnormalities detected using cranial ultrasound (cUS) and magnetic resonance imaging (MRI) have been related to neurological sequelae.
OBJECTIVE: To evaluate the additional value of MRI and assess the relationship between time of infection during pregnancy and outcome in infants with cCMV infection. METHODS AND STUDY
DESIGN: Demographic and clinical data were collected in infants with cCMV infection (1992-2013). Trimester of infection, neuro-imaging results and outcome were reviewed. Cerebral abnormalities were categorized into none, mild (lenticulostriate vasculopathy, germinolytic cysts, high signal intensity on T2-weighted images) and severe (migrational disorder, ventriculomegaly, cerebellar hypoplasia). Results were statistically analysed.
RESULTS: Thirty-six infants were eligible for analysis. cUS was performed in all and cranial MRI in 20 infants. Migrational disorders were only diagnosed using MRI (p < 0.01). In 17 infants trimester of infection was ascertained. Seven out of 10 infants infected during the first trimester had severe abnormalities on cUS (5 confirmed on MRI) and adverse sequelae; 3 had no/mild abnormalities on cUS/MRI and normal outcome. Two out of 3 infants infected during the second trimester with no/mild abnormalities on cUS/MRI had normal outcome; 1 with mild cUS and MRI abnormalities developed sensorineural hearing loss. Four infants infected during the third trimester with no/mild abnormalities on cUS/MRI had normal outcome.
CONCLUSION: Infants with a first trimester cCMV infection are most at risk of severe cerebral abnormalities and neurological sequelae. MRI, and not cUS, enables an early diagnosis of migrational disorders, which can improve prediction of outcome.