Familial idiopathic pulmonary hemosiderosis.
Two brothers, aged 3 and 6 years, respectively, had their pulmonary conditions diagnosed as idiopathic pulmonary hemosiderosis (IPH). Both boys had severe iron-deficiency anemia, chronic cough, hemoptysis, and exertional dyspnea, and one had recurrent epistaxis. The results of light microscopic lung histopathologic studies in both patients showed numerous hemosiderinladen macrophages and chronic interstitial pneumonitis. No specific patterns of immunofluorescence of the alveolar capillary basement membranes were found. The results of electron microscopic examinations showed intact alveolar and capillary basement membranes and no evidence of electron-dense deposits. The lack of clinical or biochemical evidence for renal disease as well as the absence of serum antinuclear and antibasement membrane antibodies excluded associated autoimmune disorders. Evaluation for milk-protein allergy was negative and neither child demonstrated a clinical response to a milk-free diet. Sequential pulmonary function studies performed over four years showed episodes of acute obstructive airway disease that correlated with pulmonary hemorrhage and mild persistent restrictive lung disease. The results of this family study suggested that some cases of IPH may have a genetic basis.