Patent ductus arteriosus as a natural cause of pulmonary hemorrhage in infants: a medicolegal dilemma.

Patent ductus arteriosus (PDA) is a recognized risk factor for massive pulmonary hemorrhage (MPH) in the newborn and is generally seen in association with other MPH risk factors such as prematurity. We report 6 cases of sudden and unexpected death of infants older than 4 days with MPH and PDA at autopsy. The cases were reviewed for other factors that could contribute to MPH to ascertain whether PDA is directly linked to MPH. Histology samples were examined for distribution of hemorrhage in the lungs and iron stained for hemosiderin evaluation. All of the cases had clinical histories and scene examinations which raised the differential diagnosis of mechanical asphyxia in the form of so-called overlayings. The diagnostic dilemma of attributing the MPH to the PDA as the sole cause, dual cause, or incidental finding is discussed. These cases illustrate the medicolegal dilemma faced by the pathologist, as well as the need for further research into the potential association of PDA with MPH.