Histopathology of idiopathic pulmonary hemosiderosis

Transbronchial forceps lung biopsy from a 55-year-old woman with idiopathic pulmonary hemosiderosis and hemoptysis for 6 months. Combined staining for iron (Perls' Prussian blue) and nuclear counterstaining (Kernechtrot) demonstrates alveoli filled with hemosiderin-laden macrophages and thickening of the alveolar walls.