Utility of upper endoscopy and colonoscopy in evaluating gastrointestinal luminal wall thickening found on computed tomography

Abstract

Background: Abdominal computed tomography (CT) scans are frequently performed for a variety of abdominal complaints. Not infrequently, bowel wall thickening noted on these radiographic studies of the gastrointestinal (GI) tract prompt further endoscopic evaluation. It is unclear whether the costs and risks of endoscopy are justified given the subsequent yield on endoscopic examination of this radiological finding.

Materials and methods: A retrospective study was done on patients referred to the Digestive Diseases section of a tertiary level hospital for abnormal findings seen on CT during the study period. These patients were seen over one year and their charts reviewed. The items reviewed in the charts were: age, gender, chief complaint, physical findings, ordering location, CT scan indication, CT scan abnormality, endoscopic findings, and the time interval between CT scan and endoscopic procedure.

Results: A total of 169 patients with bowel wall thickening that proceeded to an endoscopy were identified. The average age for the patients was 18 to 89 with a mean of 55 years. Females comprised 59% of the patients. The mean period from the time of the CT scan to endoscopy was 32 days. In the upper GI tract, 39 patients had bowel wall thickening. Of these, 25 had abnormal pathology on subsequent endoscopy correlating with the radiological findings. In the lower GI tract, 109 patients had bowel wall thickening. Of these, 36 had abnormal findings on the subsequent endoscopy. In this group, 10% was found to be of neoplastic origin upon further work-up. The positive predictive value (PPV) for bowel wall thickening in the UGI tract was 64%. In the lower GI tract, the PPV was 33%.

Conclusion: Thickening of the gastrointestinal tract is not uncommonly noted on abdominal CT scans. The resultant endoscopic evaluations of these findings appear to yield more when these changes are seen in the upper GI tract as compared to the lower GI tract. Luminal wall thickening in the upper GI tract seen on CT is a very useful predictor of pathology (PPV = 64%). For colonic wall thickening seen on CT, the PPV was only 33%. Nevertheless, we recommend direct visualization as 10% of these findings were found to be malignancies on follow-up.