Intrahepatic Gas Caused by Acute Gastroenteritis: Hepatic Portal Venous Gas or Biliary Tract Gas?

Purpose: Hepatic portal venous gas is not a specific disease and is often only an imaging manifestation in patients with acute abdomen. However, its appearance often indicates serious disease and poor prognosis. It is not difficult to distinguish typical portal venous gas from biliary tract gas on computed tomography because of their relatively different distribution within the liver. But the difference is not absolute.

Case description: An 82-year-old female was admitted to the emergency department due to epigastric pain, nausea and vomiting for 1 day. Intrahepatic gas was found on computed tomography (CT), which was initially diagnosed as portal venous gas, and contrast-enhanced abdominal CT was performed 3 hours after the first plain CT scan and revealed a significant reduction of intrahepatic gas, then diagnosed as biliary tract gas. Two days later, enhanced abdominal CT showed that biliary tract gas had disappeared. Continuous gastrointestinal decompression, anti-infection, rehydration and other treatments were given. After treatment, abdominal pain, nausea, vomiting and other symptoms of the patient were gradually relieved. The patient refused gastroenteroscopy and was discharged after 13 days of hospitalization.

Conclusion: Portal venous gas and biliary tract gas may have similar CT findings and be misdiagnosed, and enhanced CT examination is necessary to confirm the diagnosis.