Fatal Neonatal Mycoplasma Pneumonia Linked to Probable Vertical Transmission During UK Surge

A report in The Pediatric Infectious Disease Journal describes severe congenital Mycoplasma pneumoniae pneumonia in one preterm infant during the UK's 2023–2024 epidemic. The infant was born at 31 weeks and 4 days after prolonged rupture of membranes from 22 weeks, with suspected maternal chorioamnionitis. Respiratory distress developed immediately after birth, requiring intubation at approximately four hours and subsequent escalation to high-frequency oscillatory ventilation.

M. pneumoniae DNA was detected in endotracheal secretions collected on day 2 and in placental tissue. Placental histology showed chorioamnionitis and funisitis, and maternal and neonatal M. pneumoniae-specific IgM tests were positive. Routine bacterial cultures were negative. Erythromycin was added on day 14, when the respiratory PCR result became available. Despite intensive care, including treatment for pulmonary hypertension, the infant died on day 17.

The authors suggest considering M. pneumoniae in severe congenital pneumonia during epidemic surges. However, this single case supports probable rather than confirmed vertical transmission: maternal respiratory and genital specimens were unavailable for molecular testing, and the mother reported no respiratory illness. Placental macrolide-resistance testing was unsuccessful because of insufficient bacterial DNA. The report cannot establish whether earlier targeted treatment would have changed the outcome or whether congenital cases cluster around epidemic peaks.