A CASE OF URINOTHORAX

Abstract

SESSION TITLE: Wednesday Fellows Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: A urinothorax is a rare cause of pleural effusion which can occur in urinary obstruction or from trauma to the genitourinary system. We present a case of urinothorax in a patient with bilateral hydronephrosis. CASE PRESENTATION: A 70 year old female with metastatic cholangiocarcinoma presented with abdominal pain, anuria, and shortness of breath for three days. She was found to have an acute kidney injury with bilateral hydronephrosis and left sided forniceal rupture. Physical examination also revealed decreased breath sounds over the left hemithorax. Chest imaging revealed complete opacification of the left hemithorax with mediastinal shift to the right. She was admitted to the intensive care unit and a diagnostic and therapeutic thoracentesis was performed with removal of 1.9L of straw colored transudative fluid. Pleural fluid creatinine was 12.6. The pleural fluid creatinine to serum creatinine ratio was >1. Bilateral percutaneous nephrostomy tubes were placed and renal function and urine output improved. Chest imaging done two months later did not show any re-accumulation of pleural effusion. DISCUSSION: A urinothorax is an uncommon complication of obstructive uropathy and genitourinary tract abnormalities that can occur in malignancy or traumatic injury. It is typically a unilateral, straw-colored effusion with a pH lower than 7.40 and transudative in nature by Light’s criteria. A urinothorax has two possible mechanisms. Urine can collect in the retroperitoneal space if an obstruction is present and the fluid enters the peritoneal cavity and thereafter leaks through transdiaphragmatic holes into the pleural space. Urine may also travel through lymphatics into the pleural cavity. A high degree of clinical suspicion is needed to make the diagnosis. In patients with concomitant urinary tract infections, especially with ammonia producing organisms, the effusion may be exudative as well as having a pH higher than 7.40, thereby confusing the clinical picture. A pleural fluid creatinine to serum creatinine ratio of greater than 1 clinches the diagnosis of a urinothorax. Further confirmatory workup can be done with a renal scintigraphy study to reveal extravasation of urine from the genitourinary system into the pleural space. Treatment of a urinothorax is aimed at the management of the underlying genitourinary condition. CONCLUSIONS: A urinothorax should be included in the differential diagnosis in a patient with obstructive uropathy or recent surgical genitourinary interventions presenting with a pleural effusion. The condition is completely reversible after treatment of the underlying cause. Reference #1: Handa A, Agarwal A, Aggarwal AN. Urinothorax: an unusual cause of pleural effusion. Singapore Med J 2007; 48(11):e289–e292 Reference #2: Chandra A, Pathak A, Kapur A, Russia N, Bhasin N. Urinothorax: A rare cause of severe respiratory distress. Indian J Crit Care Med. 2014 May; 18(5): 320–322. Reference #3: Garcia-Pachon E, Romero S. Urinothorax: a new approach. Curr Opin Pulm Med. 2006; 12: 259-263 DISCLOSURES: No relevant relationships by Sujith Cherian, source=Web Response No relevant relationships by Rosa Estrada-Y-Martin, source=Web Response No relevant relationships by Bibi Aneesah Jaumally, source=Web Response