Pitfalls in the diagnosis of idiopathic pulmonary haemosiderosis.

Idiopathic pulmonary haemosiderosis is a very rare but devastating disorder. Diagnosis is sometimes difficult and the clinical course exceedingly variable, as illustrated by this report of a girl, aged 2 years 4 months, with severe iron deficiency anaemia. There was no response to iron therapy and transfusions. Sustained and striking reticulocytosis associated with low haptoglobin mimicked haemolytic anaemia. Positive faecal blood test was documented after repeated testing. There were no pulmonary symptoms. A chest radiograph showed bilateral diffuse alveolar infiltrates. Bronchoalveolar lavage fluid showed numerous siderophages. High resolution computed tomography of the thorax revealed early pulmonary fibrotic changes. Recurrent reticulocytosis appeared to be a very useful sign of recurrent bleeding episodes.