[Alveolar hemorrhage associated with intestinal inflammatory disease and Hashimoto thyroiditis]

Diffuse alveolar hemorrhage (DAH) is characterized by diffuse bleeding into alveolar spaces. Three histopathological patterns may be seen: 1) pulmonary capillaritis due to immunological aggression to the membrane, 2) diffuse alveolar damage within the context of acute respiratory distress syndrome, and 3) and "bland" DAH without alveolar or capillary damage. In the first two groups, pulmonary damage usually occurs within the context of a systemic disease. In the last, injury is usually found only in the lung, an entity called pulmonary hemosiderosis. We present a case of DAH with neither capillaritis nor diffuse alveolar damage in association with inflammatory bowel disease and Hashimoto thyroiditis. The case is interesting both because the association has not yet been described in the literature and because the presence of alveolar bleeding without evident tissue damage within the context of known autoimmune diseases may extend the field to include a new pathophysiological mechanism of pulmonary hemorrhage.