Idiopathic pulmonary haemosiderosis revisited.

Idiopathic pulmonary haemosiderosis is a rare cause of diffuse alveolar haemorrhage of unknown aetiology. It occurs most frequently in children, has a variable natural history with repetitive episodes of diffuse alveolar haemorrhage, and has been reported to have a high mortality. Many patients develop iron deficiency anaemia secondary to deposition of haemosiderin iron in the alveoli. Examination of sputum and bronchoalveolar lavage fluid can disclose haemosiderin-laden alveolar macrophages (siderophages), and the lung biopsy shows numerous siderophages in the alveoli, without any evidence of pulmonary vasculitis, nonspecific/granulomatous inflammation, or deposition of immunoglobulins. Contrary to earlier reports, corticosteroids alone or in combination with other immunosuppressive agents may be effective for either exacerbations or maintenance therapy of idiopathic pulmonary haemosiderosis.