Value of targeted testing for cytomegalovirus in preterm infants: 7 years' experience at a tertiary London hospital.

BACKGROUND: Targeted testing for cytomegalovirus (CMV) in preterm infants <21 days has two benefits: timely congenital CMV (cCMV) diagnosis, and differentiation between cCMV and postnatal CMV (pCMV). We present an audit of targeted testing for cCMV alongside rates of clinically suspected pCMV in preterm infants. METHODS: We collected data on CMV testing from 2016 to 2023 in infants born <30 weeks gestation during admission to a tertiary London neonatal centre. RESULTS: Of all infants, 77% (899/1162) were tested for CMV during their admission with 74.6% tested <21 days of age. CMV infection was confirmed in 58 infants, 4 cases of cCMV (0.4%) and 54 cases of pCMV (6.0%). One infant with cCMV died, and all were symptomatic: microcephaly, thrombocytopenia, leucopenia, white matter hyperintensity on brain imaging, but none had hearing loss. Most pCMV cases (92.6%) were symptomatic, with bone-marrow suppression (92.6%), sepsis-like syndrome (50%), respiratory (31.5%) and gastrointestinal symptoms (29.6%). All infants with cCMV and 38.9% of infants with pCMV received treatment. Overall, 6% (54/899) had symptomatic CMV disease, 16.7% of infants with CMV died during their neonatal intensive care unit admission, and 42.6% were discharged on home oxygen. CONCLUSIONS: CMV causes a substantial disease burden in infants born <30 weeks gestation, whereby 6% have symptomatic CMV disease. We show the feasibility and value of targeted cCMV and opportunistic pCMV testing. In the absence of universal screening, targeted birth testing for cCMV in infants <30 weeks gestational age should be considered.