A CURIOUS CASE OF URINOTHORAX

Abstract

TOPIC: Disorders of the Pleura TYPE: Medical Student/Resident Case Reports INTRODUCTION: Urinothorax (UT), is a rare cause of pleural effusion caused by accumulation of urine in the pleural space. It is usually the result of trauma or obstruction of the urinary tract. We present a case of a tension UT developed due to accidental displacement of a ureteral stent. CASE PRESENTATION: 80-year-old male with medical history significant for chronic kidney disease stage III, nephrolithiasis, prostate cancer status post prostatectomy and hospitalizations for obstructive uropathy requiring ureteral stent placement presented with progressively worsening dyspnea and acute encephalopathy. He was hypotensive and hypoxic requiring admission to the intensive care unit. Of note, patient was discharged 2 days ago after exchange of double J ureteral stent and removal of nephrostomy tube. Physical examination revealed a confused elderly male in respiratory distress. Patient had absent breath sounds and dullness on percussion of the right chest. Laboratory investigations were consistent with acute kidney injury. His imaging showed complete opacification of right hemithorax, consistent with large right sided pleural effusion and mediastinal shift to the left. Commuted tomography (CT) of the chest showed proximal aspect of the ureteral stent had migrated into the right pleural space. A chest tube was placed with drainage of yellow colored fluid and resolution of hypotension and hypoxia. On analysis, pleural fluid was transudative in nature with creatinine of 10.5 mg/dl. The findings of pleural fluid analysis including serum creatinine ratio greater than 1 and imaging confirmed the diagnosis of UT. The chest tube was kept in place for the drainage of urinoma and J-stent was removed under general anesthesia with repeat imaging showing resolution of the pleural effusion. DISCUSSION: UT usually presents as unilateral or bilateral pleural effusion usually due to trauma or obstruction of urinary tract. It has a male predominance and can occur at any age. Traumatic etiologies including surgical injuries, blunt trauma, medical procedures etc. are common causes of UT. Less commonly, UT can be due to obstructive causes due to prostate disease, left renal vein obstruction etc. Patients usually present with symptoms of flank pain, shortness of breath, or decreased urine output. Diagnosis is made on pleural fluid analysis with pleural fluid to serum creatinine ratio greater than 1 with associated obstructive or traumatic uropathy. Treatment of UT is by draining the pleural fluid and correcting the underlying etiology. To our knowledge, this is the first case reported of urinothorax secondary to ureteral stent displacement into the pleural space. CONCLUSIONS: UT is a rare but curable cause of pleural effusion. Though there is paucity of data, however, according to the reported causes patients have favorable prognosis if diagnosed early. REFERENCE #1: Toubes ME, Lama A, Ferreiro L, Golpe A, Álvarez-Dobaño JM, González-Barcala FJ, San José E, Rodríguez-Núñez N, Rábade C, Lourido T, Valdés L. Urinothorax: a systematic review. Journal of thoracic disease. 2017 May;9(5):1209. REFERENCE #2: Garcia-Pachon E, Romero S. Urinothorax: a new approach. Current opinion in pulmonary medicine. 2006 Jul 1;12(4):259-63. REFERENCE #3: Stark DD, Shanes JG, Baron RL, Koch DD. Biochemical features of urinothorax. Archives of internal medicine. 1982 Aug 1;142(8):1509-11. DISCLOSURES: No relevant relationships by Dheera Grover, source=Web Response No relevant relationships by Prashant Grover, source=Web Response No relevant relationships by Simrina Sabharwal, source=Web Response