Idiopathic Pulmonary Hemosiderosis

Abstract

The characteristic features of idiopathic pulmonary hemosiderosis (IPH) are recurrent intra-alveolar bleeding, accumulation of hemosiderin-laden macrophages (siderophages), and iron-deficiency anemia. The disease most commonly affects children and young adults. The diagnosis is established by excluding all other known causes of diffuse alveolar hemorrhage (DAH) (Table 29.1). The histopathological examination reveals bland alveolar hemorrhage (Figure 29.1a) (without capillaritis, or inflammation of other blood vessels), type II epithelial hyperplasia with capillary dilatation, and tortuosity. Hemosiderin-laden macrophages are seen in the alveolar spaces and interstitium. Breaks in the continuity of the capilllary basement membrane and focal ruptures are seen (Figure 29.1b).