Urinothorax in the Setting of Acute Renal Failure Secondary to Bilateral Ureteropelvic Junction Obstruction

Urinothorax refers to urine within the pleural space; it is an exceptionally rare type of transudative pleural effusion. The existence of urinothorax as a clinical entity is largely unknown to the average general internist. We describe a case of left-sided urinothorax in a patient who presented in acute renal failure in the setting of bilateral obstructing ureteropelvic renal calculi. This memorable and comprehensive case report serves to increase awareness and knowledge among clinicians of this relatively novel clinical phenomenon as well as to describe a typical approach to diagnosis and management.