Ascitic fluid bilirubin concentration as a key to choleperitoneum.

Total bilirubin concentration was measured in the ascitic fluid and serum of 65 patients with various types of ascites to determine the normal range of these parameters. The mean (+/- SD) ascitic fluid bilirubin was 0.7 +/- 0.8 mg/dl, and the mean ascitic fluid/serum bilirubin ratio was 0.38 +/- 0.44. Subsequently, I recognized choleperitoneum in a patient with bile-stained ascites preoperatively, because the ascitic fluid bilirubin was 18.5 mg/dl and the ratio was 7.1. Laparotomy documented a ruptured gallbladder. An ascitic fluid bilirubin concentration greater than 6 mg/dl with an ascitic fluid/serum bilirubin ratio greater than 1.0 appears to be characteristic of choleperitoneum.