Urinothorax: a rapidly accumulating transudative pleural effusion in a 64-year-old man.

We report the case of a 64-year-old man who developed a rapid, right-sided pleural effusion. On initial presentation to the emergency room, the patient had fever and flank pain consistent with a ureteral obstruction (due to a bladder tumor) and associated hydronephrosis that had required previous placement of a pericutaneous nephrostomy tube. After a 10-day stay in the hospital, the patient's urine output ceased. Symptomatic dyspnea with radiographic evidence of a new pleural effusion soon followed. Urinothorax was the etiology of the effusion.