Massive pleural effusion attributed to high-dose cyclophosphamide during conditioning for BMT.

A 37-year-old male developed massive pleural effusion leading to respiratory failure and electromechanical dissociation within 24 h after the second dose of 4200 mg cyclophosphamide (CY) during conditioning for allogeneic bone marrow transplantation for chronic myelogenous leukemia. After resuscitation and bilateral pleural drainage he recovered within 1 day. Subsequently, total body irradiation was given and with a delay of 1 day the transplantation procedure was continued without major complications. No explanation for this idiosyncratic reaction other than the administration of high dose CY in combination with mesna rescue was found. This reaction has not been reported before in the literature.