Fresh Milk Administration and Cytomegalovirus Infection in Preterm Neonates: A Case Study Approach

Fresh human milk for preterm infants is associated with a reduction of bronchopulmonary dysplasia, to improve survival without major complications, and with an increased breastfeeding duration. Nevertheless, its administration is frequently restricted due to the risk of post-natal cytomegalovirus infection. Looking at 12 years of medical records in a tertiary neonatal intensive care unit using fresh milk without restriction, we retrospectively collected cases of symptomatic postnatal cytomegalovirus infection in preterm infants born under 32 weeks receiving fresh milk. We present the prevalence and outcome of postnatal milk-acquired cytomegalovirus infection.

Among 2554 preterm newborns < 32 weeks hospitalized during the study period (2009-2020), 1396 (54%) had received fresh milk, and eight newborns developed a symptomatic postnatal cytomegalovirus infection, representing an incidence of 5/1000 patients. Clinical presentation was severe in three out of the eight cases.

Two patients received valganciclovir, and one patient died of the infection. After 2 years of follow-up, two patients had neurodevelopmental delay, including one who had abnormalities on brain magnetic resonance imaging before the cytomegalovirus infection. Liver function was normal. Breastfeeding was continued for all surviving patients with a mean duration of 4.5 months.

Fresh milk administration without restriction was associated with a limited number of symptomatic postnatal cytomegalovirus infections. Neonatologists must be aware of this risk to better diagnose and manage the infection. Multicenter studies are required to investigate which preterm infants are most at risk of severe postnatal cytomegalovirus, and to determine the optimal approach to prevention and treatment.