Diagnosis Bronchoalveolar lavage Diagnosis of idiopathic pulmonary hemosiderosis involves demonstration of a combination of characteristic clinical findings, iron deficiency anemia, and hemosiderin-laden macrophages in bronchoalveolar lavage (BAL) fluid or lung biopsy specimens plus no evidence of small-vessel vasculitis (pulmonary capillaritis) or another explanatory diagnosis; it is confirmed by lung biopsy if other findings are inconclusive.