[Alveolar opacities and busulfan pneumonia].

A case of toxic pneumonia due to busulfan is reported in a man aged 65 treated for three years with busulfan for chronic myeloid leukaemia. He was admitted to hospital for dyspnoea, cough, fever and presented with crepitations, dense alveolar opacities, and a restrictive ventilatory defect. Trans-bronchial biopsy showed a filling of the alveoli by fibroblastic tissue, as well as voluminous dystrophic pneumocytes. Four months later in spite of steroid therapy the clinical state and respiratory function were worse. The alveolar opacities have regressed but some diffuse interstitial opacities had appeared. This new case is a reminder that the appearance of alveolar opacities in a patient treated with busulfan should raise the possibility of a toxic pneumonitis to busulfan in the differential diagnosis. This observation also underlines the role of the initial endo-alveolar fibrosis in the ultimate development of interstitial fibrosis.