Hemothorax due to hemorrhagic disease of the newborn

A three day old male, term infant with hemothorax due to hemorrhagic disease of the newborn was treated successfully with vitamin K and thoracocentesis. Exclusive breast feeding and absence of vitamin K prophylaxis were important diagnostic clues, although hemothorax as a sole manifestation of hemorrhagic disease of the newborn is rare. This case highlighted the good prognosis of an uncommon complication when prompt diagnosis and appropriate treatment are instituted. The importance of vitamin K prophylaxis to all newborns is emphasized.