Uroperitoneum in cats: 26 cases (1986-1995).

Uroperitoneum (UP) was diagnosed in 26 cats. Trauma was the most common cause (84.6%), including blunt abdominal trauma (59.1%), urethral catheterization (31.8%), and bladder expression (9.1%). The bladder was the most frequent site of urine leakage following blunt abdominal trauma (84.6%), while the urethra was the most common site following catheterization (71.4%). Common historical complaints were anuria (53.8%) and vomiting (50%). On physical examination, the bladders were palpable in nine (69%) of 13 cases; four of the nine had ruptured bladders. The ability to urinate did not exclude a diagnosis of UP since four noncatheterized cases reportedly urinated. Twenty-five cases were azotemic on presentation. The creatinine or potassium (K+) concentration in the serum compared to that in the peritoneal effusion (mean ratio, 1:2 and 1:1.9, respectively) was a useful indicator for UP. When performed, positive contrast radiography was diagnostic. Drainage of urine from the peritoneal cavity appeared to improve patient stabilization. Morbidity and mortality depended largely on the severity of associated injuries.