[A patient with high creatinine levels but no renal failure: reversed autodialysis in a patient with a ruptured bladder].

Background: In case of a ruptured bladder with urine leakage into the peritoneal cavity 'reversed autodialysis' can occur, in which urea and creatinine diffuse back into the bloodstream via the peritoneum. This causes clinical signs of pseudorenal failure, with raised concentrations of creatinine and urea. The urea/creatinine ratio does not change.

Case Description: A 34-year-old female patient experienced increasing abdominal pain 3 days after laparoscopic myomectomy. Acute renal failure was suspected because of increased serum concentrations of creatinine and urea, but no cause could be found. There was a build-up of fluid in the abdominal cavity, which proved to be urine originating from an iatrogenic rupture of the bladder. Serum levels normalised following repair of the rupture.

Conclusion: If serum creatinine levels rise rapidly following abdominal surgery or blunt abdominal trauma the bladder should be examined for possible perforation, particularly if the abdominal dimension increases. A ruptured bladder leading to pseudorenal failure is an indication for rapid surgical intervention.