Background: To assess hearing outcomes at 24 months of age in infants with mild congenital cytomegalovirus (cCMV) infection, depending on whether they have received antiviral treatment or not.

Methods: A retrospective study within the European Registry of Children with cCMV was performed. Included children had cCMV diagnosed in utero/in the first 21 days of life, with normal physical examination, alanine aminotransferase <80 U/L and platelets >100,000 cs/mm 3 and absence of hearing loss (HL) at birth. Cranial ultrasound (cUS) and/or cranial magnetic resonance imaging was normal or with minor findings (isolated lenticulostriate vasculopathy and/or germinolysis/caudothalamic or subependymal cysts, and/or focal/multifocal white matter involvement). The main outcome was the presence of HL at 24 months of age.

Results: One hundred ninety-six patients met inclusion criteria. A total of 34.7% received antiviral treatment with valganciclovir/ganciclovir. Children treated had lower gestational age, birth weight and head circumference, and maternal primary infection was less frequent. Among treated children, 21.3% presented minor findings in cUS versus 6.3% in nontreatment group ( P = 0.003). Nine patients (4.6%) developed HL at 24 months. Among children with HL, 20% presented minor findings in cUS versus 11.3% in non-HL group ( P = NS). HL rate was similar in treated and nontreated groups (4.6% vs. 6.3%; P = 0.6).

Conclusions: One-third of the children were treated with antivirals and infants with minor neuroimaging findings at birth were more likely to receive antiviral. There were no differences in the prevalence of HL at 2 years of age between treated and not-treated children. Minor neuroimaging findings were not clearly associated with an increased risk of delayed onset HL.