Diffuse alveolar haemorrhage with suspected idiopathic pulmonary hemosiderosis and decrease in lung diffusing capacity and chronic respiratory failure.

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease of unknown aetiology that causes recurrent episodes of diffuse alveolar haemorrhage (DAH). A male patient in his 50s had repeatedly experienced hemoptysis for the past 6 years, along with a decrease in the pulmonary diffusing capacity and chronic respiratory failure. After a 6-year follow-up, the patient experienced sudden exacerbation of hemoptysis and respiratory failure, and he was hospitalised. A CT of the chest revealed diffuse pulmonary infiltrates, whereas the bronchoalveolar lavage revealed hemosiderin-laden macrophages. Thus, the patient was diagnosed with DAH. As all diseases that cause DAH other than IPH were negative, the patient was suspected of IPH. He was treated with a combination of glucocorticoids and azathioprine, and his hemoptysis and chronic respiratory failure improved; however, the decrease in the pulmonary diffusing capacity did not improve. Treating adult-onset IPH with glucocorticoids and azathioprine might not improve pulmonary diffusing capacity.