Urinothorax and Empyema: Presentation of an Unusual Complication of a Rare Condition.

A 68-year-old male with a history of metastatic bladder cancer and urinary obstruction presented with intractable hiccups and chest pain is presented in this case. He was found to have a unilateral pleural effusion in addition to ipsilateral renal metastasis abutting the diaphragm. Imaging revealed empyema. Thoracentesis revealed positive cultures and a lack of malignant cells on cytology. Comorbid urinary obstruction and urinary tract infection suggested the rare diagnosis of an infected urinothorax. Thoracentesis also revealed pleural fluid creatinine greater than serum creatinine, meeting the most specific diagnostic criteria for urinothorax and establishing the diagnosis. Treatment aimed at evacuating the pleural space without addressing the comorbid bladder obstruction led to an unfavorable outcome in this case.