[Fatal lung hemorrhage in complex pulmonary angiodysplasia in a case of mongolism].

A case of sudden and unexpected death of a boy with Down-Syndrome is reported. Death was due to acute excessive haemorrhage from the lungs. There were no cardiac anomalies. Histology revealed in addition to mediahyperplasia, intimaproliferation and occlusions, multiple foci of anomalous ectatic blood vessels predominantly in the lungs, some of which ruptured and bled into adjacent airways. Evidence of previous less severe bleeding episodes was present. Further investigation showed a familial occurrence of the blood vessel anomaly.