Delayed enhancement of ascites following high-dose contrast CT for liver metastases.

Enhanced ascites has been described as a pathognomonic CT sign of urinary-peritoneal fistula. We have seen two cases of slowly enhancing ascites demonstrated with delayed contrast CT in the absence of urinary-peritoneal fistula. Knowledge of this phenomenon is important because hyperdense enhanced ascites can simulate urinary-peritoneal fistula or intraperitoneal hemorrhage.