Assessment of the Validity of Computed Tomographic Enterography for Diagnosing Active Crohnʼs Disease

Abstract

Purpose: Emerging research suggests that computed tomographic enterography (CTE) provides a noninvasive method for diagnosing Crohn's disease (CD). Many CTE studies have shown a correlation between CTE and standard diagnostic techniques for assessing CD of the small bowel. This retrospective review evaluated the validity of CTE for assessing CD in patients with anal, rectal, colonic, and small bowel involvement with or without fistulous disease. Methods: Medical records for consecutive adult patients with suspected or confirmed CD who had undergone CTE for active disease assessment or routine evaluation were reviewed. Results from CTE were compared with those from other diagnostic and interventional assessments, including colonoscopy, capsule endoscopy (CE), and direct surgical examination. Results: The analysis included 25 patients (mean age, 41 y); 18 had previous CD diagnosis, and 7 had no prior CD history. Of the patients with diagnosed CD, 5 had CD involving the small bowel only, 3 had colonic, anal, and/or rectal involvement only, and 10 had CD involving multiple locations; 7 had prior bowel resection, and 6 had current fistulas. Additional assessments were conducted within 14 months of CTE (median, 3 wk; range, 2 d–14 mo). Patients underwent colonoscopy only (N = 15), colonoscopy with CE (N = 5), CE only (N = 1), or surgical intervention (N = 4). Results of CTE were in concordance with 74% of colonoscopy and CE results. Concordance was observed between CTE and colonoscopy for diagnosing ileal or colonic/rectal disease activity (N = 5 and N = 6, respectively) and lack of ileal or colonic/rectal disease activity (N = 3 and N = 4, respectively) and between CTE and CE for ileal disease activity (N = 1) and lack of small bowel disease activity (N = 1). Concordance between CTE and surgical examination or colonoscopy for detecting fistulae was 50%, with CTE detecting perianal (N = 1) and enteroenteric (N = 2) fistulae. Conclusion: In this retrospective study, CTE demonstrated a high level of agreement with standard diagnostic measures and direct surgical evaluation on assessments of active ileal or colonic CD. These findings suggest CTE may provide a valuable, noninvasive diagnostic tool with detection capabilities complementary to more invasive techniques. The fact that CTE demonstrated a moderate capability for diagnosing active fistulous disease suggests a potential need for more sensitive techniques for detecting fistulae.