Pan-enteric capsule endoscopy accurately diagnoses IBD

The use of pan-enteric capsule endoscopy (PCE) leads to high diagnostic yield for inflammatory bowel diseases (IBDs), often even matching that of colonoscopy and magnetic resonance enterography (MRE), reports a recent meta-analysis.

Of the 14 eligible studies included, seven looked at PCE in Crohn’s disease (CD) and seven in ulcerative colitis (UC). Pooled analysis of the CD studies showed that compared with all comparator tests, PCE was 25 percent more likely to detect active disease on a per-patient basis, an effect that fell shy of statistical significance (odds ratio [OR], 1.25, 95 percent confidence interval [CI], 0.85–1.86). [J Gastroenterol Hepatol 2022;doi:10.1111/jgh.16007]

Comparing PCE to endoscopic tests, including colonoscopy or double balloon enteroscopy, slightly improved its relative diagnostic value (OR, 1.30, 95 percent CI, 0.85–1.98). Compared against MRE alone, PCE showed marginally better diagnostic yield, though still failing to reach statistical significance (OR, 1.32, 95 percent CI, 0.79–2.20).

Per-segment analysis also showed that PCE was slightly better than colonoscopy in the terminal ileum (OR, 1.19, 95 percent CI, 0.78–1.79) and colon (OR, 1.14, 95 percent CI, 0.76–1.71).

Pooled analyses of the UC studies focused on diagnostic sensitivity and showed that PCE reached a high value of 93.8 percent (95 percent CI, 87.6–97.0), with very low inter-study heterogeneity of evidence. Meanwhile, the pooled diagnostic specificity was lower at 69.8 percent and was associated with significant heterogeneity.

PCE had a pooled positive predictive value of 88.8 percent for UC, while its negative predictive value was 80.1 percent. The diagnostic OR was 24.0 (95 percent CI, 10.4–55.3).

“The diagnostic accuracy of PCE in the detection of CD was equivalent to MRE and endoscopic assessment on both per-patient and per-segment analyses. In fact, the pooled per-patient ORs for CD showed a trend to superiority over endoscopy and MRE,” the researchers said.

“For UC, PCE has excellent diagnostic sensitivity but is not suggested to be a replacement for faecal calprotectin or colonoscopy. PCE may have a role in UC in certain patient groups, and its use should be tailored based on the clinical circumstances,” they added.

In assessing the overall diagnostic yield and sensitivity, the researchers noted a potential effect of using newer vs older capsule devices, prompting subgroup analyses.

For CD, CCE2 capsules were defined as older-generation, while the Pillam Crohn’s device was defined as newer-generation. The latter, assessed in 156 patients, yielded a diagnostic OR of 1.46 (95 percent CI, 0.82–2.59). Meanwhile, the former’s diagnostic OR was 0.96 (95 percent CI, 0.37–2.41).

A similar effect was reported for PCE in UC. Newer-generation capsules had a pooled sensitivity of 97.2 percent, while older-generation devices only reached 89.1 percent. Specificity was much lower for newer capsules (46 percent vs 82.6 percent).

“Our study reports numerous significant results and is, to the authors’ knowledge, the first meta-analysis to report on the diagnostic utility of PCE systems in IBD,” the researchers said. Key limitations included a lack of gold standard for CD diagnosis and an overall paucity of eligible studies.