Diffuse alveolar hemorrhage as a manifestation of Behçet disease.

Diffuse alveolar hemorrhage (DAH) is a rare life-threatening condition which refers to the presence of red blood cells within alveoli deriving from hemorrhage originating in the pulmonary microvasculature. It differs from alveolar filling, in which blood cells derive from localized bleeding, usually of bronchial origin. DAH may be part of diffuse alveolar injury of any origin. DAH should be considered a medical emergency due to the significant morbidity and mortality associated with respiratory failure, when secondary to impaired oxygen uptake from alveoli filled with erythrocytes. Patients with alveolar hemorrhage present with non-specific symptoms like dyspnea, cough and hemoptysis, which is not always present. They may develop acutely or insidiously over a few days. We present a case of a patient with probable Behçet's disease complicated by pulmonary capillaritis and DAH resulting in refractory respiratory failure and death.