A sudden and unexpected death, at 26 hours of age, of a term infant with no identifiable risk factors either in the prenatal or in the immediate neonatal period is described. The most remarkable postmortem findings were confined to the lungs, which had many areas of aspirated amniotic fluid, as well as extensive areas of bronchopneumonia. Postmortem cultures of the lung revealed Citrobacter freundii. This case is an atypical presentation of this devastating neonatal infection, both because of the absence of central nervous system involvement and because of the total absence of clinical signs before death.