Diagnosis of small bowel inflammation using small bowel capsule endoscopy combined with abdominal CT scan

Abdominal computed tomography (CT) scans are simple to perform and widely used in evaluating small bowel inflammation. However, detailed evaluation of small intestinal mucosa is difficult with CT. Conversely, small bowel capsule endoscopy (SBCE) is noninvasive and useful for evaluation of mucosal inflammation. We evaluated presence or absence of mucosal inflammation by SBCE in patients with CT findings of suspected small bowel inflammation and analyzed their backgrounds.

The Lewis score was determined by SBCE, and scores ≥ 135 placed 65 patients in the enteritis group and scores of < 135 placed 87 patients in the pseudoenteritis group.

Blood tests revealed higher C-reactive protein (CRP) levels in the enteritis group ( P < 0.01). Regarding comorbidities, chronic renal failure ( P < 0.01) and carcinoma ( P = 0.05) were more common in the enteritis group, as was use of proton pump inhibitors ( P = 0.02). Target sign, accordion sign, and fat stranding/centipede sign, which are known findings on CT of small intestinal inflammation, were more frequently observed in the enteritis group ( P < 0.01). Small intestinal wall thickness was greater in the enteritis group (5.3 mm vs 3.4 mm, P < 0.01) and the cut-off value was 4.15 mm.

Backgrounds of patients with inflammatory mucosa included high CRP, use of nonsteroidal anti-inflammatory medications, chronic renal failure, and cancer. If a patient with a thickened small intestinal wall (> 4.15 mm) on CT has these characteristics, it may be worth considering performing SBCE.