Ascites: not always the usual suspects.

A case report of a 44-year-old woman with an infrequent cause of ascites, i.e. intraperitoneal urine leakage, is presented. Urinary ascites due to spontaneous bladder rupture or fistula after radiation therapy for cervical cancer is not a rare complication and can develop several years after initial treatment. Diagnosis of urinary ascites should be suspected in patients with ascites and a history of radiation therapy for a bladder or a gynaecological disease. Measurement of urea and creatinine levels in urine, ascites and plasma is a simple and non-invasive diagnostic test. In physiological conditions, the ascites/plasma creatinine ratio approximates a ratio of one to one. This ratio is elevated to a value of 5/1 in case of urinary ascites. Although cystoscopy and imaging techniques such as cystography and computed tomography (with or without cystography) are extremely helpful, definitive diagnosis is frequently based on intraoperative findings, because of the lack of pathognomonic symptoms or signs. Surgery is the treatment of choice.