Mesenteric and portal vein gas: computerized tomography findings and clinical significance

Gas in the mesenteric or portal veins (PVG) is an uncommon entity. It was first described only in patients with mesenteric ischemia and bowel gangrene. Later, several reports described other causes for PVG in which conservative treatment was successful. In the past, the diagnosis was made by vague signs in abdominal plain films. Since the era of computerized tomography (CT) scan the diagnosis became more objective, but nevertheless it is still an elusive entity. Our objective was to relate clinical and CT findings with outcome of patients with PVG, and to determine the indications for surgical treatment.

Six-year records of patients from one general hospital with CT scan findings of gas in the mesenteric or portal veins were retrospectively studied, together with details of the clinical presentation, hospital course and outcome.

Between 1995 and 2000, 12 patients with findings of mesenteric and portal vein gas were identified. In 7 of 12 patients (58%) PVG developed secondary to ischemia of the small or large bowel, with mortality of 86%. Metabolic acidosis was the prominent laboratory finding. Pneumatosis intestinalis was present in all of these patients. Two patients with PVG had inflammatory bowel disease and both recovered with conservative management. Another 2 patients who were treated conservatively died. One patient had severe pancreatitis and died 2 weeks after PVG was diagnosed, from septic complications, while the other patient admitted with septic shock, died of multiorgan failure. In the last patient, PVG was diagnosed in a CT scan performed to investigate fever of unknown origin. She survived with no specific treatment.

We suggest that patients in whom PVG is found by CT scan should be treated according to their clinical status, and underlying disease. Patients suspected of having an ischemic mesenteric event should be immediately explored.