Association of Contrast-Enhanced CT Findings with Etiology and Outcome in Patients with Portal Venous Gas and Pneumatosis Intestinalis: A Single Center Case Series Study

Abstract

Background: Contrast-enhanced computed tomography (CT) is a reliable diagnostic tool often used to investigate the etiology of portal venous gas (PVG) and pneumatosis intestinalis (PI). However, there are few reports that offer an analysis of the relationship between particular CT findings and clinical outcomes. In this paper, we sought to close that gap and present the results of our analyses that reveal which CT findings are correlated with life-threatening cases.Methods: 39 patients were diagnosed with PVG or PI from contrast-enhanced CT scans and underwent treatment at St. Mary’s Hospital from January 2009 to December 2018. We reviewed patients’ medical charts, laboratory data, and CT scan images retrospectively. We defined cases resulting in operation or death as group 1, and patients with conservative treatment who survived as group 2. We then analyzed the relationship between each CT finding and clinical feature.Results: The primary underlying diseases identified for PVG and PI were bowel ischemia (13/39), enteritis (9/39), constipation (5/39), iatrogenic disease (4/39), and hemodialysis (3/39). Poor enhancement of the intestinal wall and extrahepatic venous gas were correlated with bowel ischemia (p=0.0002 and p=0.0003, respectively). Free air was less correlated with bowel ischemia (p=0.02). Wall thickness was correlated with enteritis (p=0.02). Mortality in cases with bowel ischemia and perforation was quite high (60%) even if patients underwent surgery (33.3%). Conversely, patients with enteritis, constipation, hemodialysis and gastric dilatation who did not require surgery resulted in more favorable outcomes with conservative treatment. In the multivariate analysis, extra hepatic venous gas was the only solitary factor correlated with group 1 (p=0.0008).Conclusions: Extra hepatic venous gas was the strongest predictive factor of clinical outcome in contrast-enhanced CT findings correlated with bowel ischemia and required surgical treatment. The other CT findings were useful in diagnosing the underlying disease, but were not correlated with clinical outcomes. The necessity for surgical treatment remains dependent on the root cause.