Acute respiratory failure during first cyclophosphamide infusion in a patient with systemic lupus erythematosus

We present a report of what we believe was an extremely rare case of hyperacute respiratory failure caused by first time exposure to cyclophosphamide in a 40-year-old woman with systemic lupus erythematosus. The patient was extensively evaluated for alternative etiologies with negative results. Treatment with methylprednisolone and high doses of human immunoglobulin resulted in gradual improvement of the patient's condition. We review the literature with regard to cyclophosphamide-induced lung toxicity.