Diffuse alveolar hemorrhage secondary to ANCA ‐associated vasculitis in a patient with Down syndrome

Diffuse alveolar hemorrhage ( DAH ) is a rare disease characterized by dyspnea, cough, hemoptysis, and new alveolar infiltrates. Among the various underlying disorders, vasculitis is believed to play a significant role in the pathogenesis of DAH . Here we report the first case of a patient with D own syndrome who developed DAH secondary to anti‐neutrophil cytoplasmic antibody‐associated vasculitis. This case highlights the significance of vasculitis as well as pulmonary hypoplasia and vulnerability associated with D own syndrome in the development of DAH .