[Acute respiratory failure after treatment with cyclophosphamide in a patient with proliferative glomerulonephritis].

Cyclophosphamide is an alkylating immunosuppressant drug that is used mainly in neoplastic and immunologic diseases. Lung toxicity due to treatment with cyclophosphamide, though rare, often has a poor prognosis. Diagnosis of the lung lesion is difficult because these patients have associated immunosuppression and a consequent risk of opportunistic lung infections. We report the case of a man with acute respiratory distress syndrome after treatment with cyclophosphamide for proliferative crescentic glomerulonephritis. The diagnosis of lung lesion due to cyclophosphamide was based on ruling out other possible causes. The principal diagnostic tool used was bronchoalveolar lavage. The patient progressed satisfactorily, responding adequately to corticosteroids and then maintenance therapy, without the need for mechanical ventilation.