Risk of Symptomatic Infection after Non-Primary Congenital Cytomegalovirus Infection

Cytomegalovirus (CMV) is the leading cause of congenital infection. Its occurrence is phenotypically heterogeneous. The type of maternal infection, primary or non-primary, is an important factor related to the symptomatic disease, the primary infection was long considered the only cause of severe neonatal disease. We aimed to analyze the association of primary and non-primary infection with pathological outcomes in infants and with long-term sequelae at follow-up. This was a monocentric retrospective observational study on a population of 91 infants diagnosed with a CMV infection at the Neonatal Care Unit of Neonatology at the Sant'Anna Hospital of Turin during the period of June 2005 to December 2018. Infants underwent clinical, laboratory, and neuroradiological evaluations at birth. Subsequently, the patients were monitored in an auxological, neurodevelopment, and audiological follow-up. Regarding primary vs. non-primary infection, we found a higher percentage of incidence of symptomatic and neurological localized infection, as well as long-term sequelae in the latter. However, no significant difference between the two populations was found. We underline the possibility of re-infection in previously immunized mothers (non-primary infection) with unfavorable neonatal and long-term outcomes.