Gas in the hepatic portal venous system. A diagnostic clue to an occult intra-abdominal abscess.

Gas within the hepatic venous system on abdominal roentgenogram prompted exploratory laparotomy in a patient with repeated rigors and high fever following total hip replacement. Although the patient had no localizing abdominal symptoms or signs, an intra-abdominal abscess was found and cured by surgical drainage and antibiotics. Occult, life-threatening, but treatable abdominal disease may be detected by the unusual roentgenographic finding of portal venous gas.