Hepatic Portal Venous Gas

An abdominal radiograph shows diffuse distention of the small bowel, relative paucity of colonic gas and hepatic portal venous gas at the corner of the image.

Facts:

• Rare condition occurring when intraluminal gas and/or gas produced by intestinal bacteria enters the portal venous circulation
• Initially thought to be an ominous sign with an estimated mortality of 75%-80% (more recently, mortality rates are 25%-35%)
• Main factors that allow development of portal venous gas: intestinal wall alteration, bowel distention, ischemia and sepsis

Etiology:

• Most common = intestinal ischemia with or without documented mesenteric thrombosis, necrotizing enterocolitis (NEC)
• Others = C.difficile colitis, peptic ulcer disease, gastric cancer, diverticulitis, abdominal trauma, intra-abdominal abscess, inflammatory bowel disease
• Iatrogenic = complications of endoscopic and radiological procedures

Imaging

• Diagnosis can be made by abdominal x-ray or ultrasound, but CT is the gold standard
• Branching lucencies extending to within 2 cm of the liver capsule (predominantly in the anterior-superior aspect of the left lobe)
• On US, it appears as echogenic particles flowing within the portal vein

Our case - patient with sepsis, severe ischemic/infarcted colitis and end-staged pancreatic cancer

Reference:

Alqahtani S, Coffin CS, Burak K, et al. Hepatic portal venous gas: a report of two cases and a review of the epidemiology, pathogenesis, diagnosis and approach to management. Can J Gastroenterol 2007; 21:309.