Video capsule endoscopy (VCE), a valuable diagnostic tool in patients with small-bowel pathology, is associated with the risk of capsule retention, particularly in patients with Crohn’s disease (CD).(1) Video capsule retention is defined as retention of the capsule in the digestive tract for at least 2 weeks that may require intervention for removal.(2)
A prospective cross-sectional study (SPaCE) evaluating the accuracy of VCE in comparison to ileocolonoscopy to identify small-bowel lesions in adult patients with spondyloarthropathies was reported for 64 patients.(3) Lesions consistent with CD were found on ileocolonoscopy in 10.7% and on VCE in 42.2% (P=.035). Elevated fecal calprotectin was significantly associated with small bowel CD (odds ratio [OR] 4.5, 95% confidence interval [CI]: 1.9–19.9; P=.042). No correlation was observed with the presence of gastrointestinal symptoms, C-reactive protein or PROMETHEUS® IBD sgi Diagnostic™ test results. The mean Lewis score of small bowel inflammation on VCE was 855±361 (normal LS <135), indicating moderate-to-severe small bowel involvement (LS >790). VCE found lesions consistent with CD in all patients diagnosed with CD on ileocolonoscopy and in those with equivocal ileocolonoscopy findings. Ileocolonoscopy failed to diagnose CD in any patients with equivocal VCE results. After diagnosis of CD by VCE, a switch of treatment to adalimumab produced complete mucosal healing in over 50% of cases by 6 months. The results of this study indicate that gastrointestinal symptoms are an unreliable indicator of the likelihood of CD in patients with spondyloarthropathies, and that VCE is superior to ileocolonoscopy in detecting small-bowel CD in this patient population.
The patency capsule test was developed to minimize the risk of video capsule retention, and several studies have evaluated its utility.(1)
A retrospective analysis evaluated predictive factors for small bowel patency in 151 patients with CD.(4) In the 28% of patients with patency capsule retention, multivariate analysis found that independent risk factors for capsule retention were stricturing disease (OR = 10.16, P <.001), penetrating disease (OR = 11.73, P=.001), left-sided colonic lesions (OR = 3.77, P=.038), and ileal strictures (OR = 9.76, P=.003). Previous intestinal surgery protected against retention (OR = 0.16, P=.006).
A retrospective, multicentre study evaluated the clinical benefit of the patency capsule test before VCE in 406 patients with established CD.(1) In 132 patients (32.5 %), VCE was performed without a prior patency capsule test. The patency capsule test was performed in the remaining 274 patients (67.5%) and was negative in 193 patients (47.5%). VCE was performed in 343 patients (84.5%) and the capsule was retained in the small bowel in 8 patients (2.3 %). The risk of retention was 1.5 % without a prior patency capsule test and 2.1 % after a negative patency capsule test (P = .9). Notably, the retention risk was 11.1 % (n=18, P =.01) after a positive patency capsule test.
The literature thus suggests that capsule retention is uncommon in patients with CD, and routine patency capsule tests do not appear to be useful.(1) The patency capsule test may be more useful in patients with a high risk of retention, such as those with small-bowel obstruction, but a larger study is needed to better identify risk factors to allow development of a systematic workup strategy before VCE.(4)
The Korean Gut Image Study Group has developed guidelines for use of VCE in the following situations: diagnosis of obscure gastrointestinal bleeding, small-bowel preparation for VCE, diagnosis of CD, and diagnosis of small-bowel malignancy.(5) The guidelines concluded that VCE is the most sensitive diagnostic modality for detecting mucosal lesions in patients with suspected or established CD and that VCE is useful for diagnosing CD after negative ileocolonoscopy and small-bowel radiology when there is a strong suspicion of CD. The study group recommended small-bowel radiology or the patency capsule test before VCE in patients with suspected or established CD. The European evidence-based consensus for endoscopy in inflammatory bowel disease (IBD) also recommends cross-sectional imaging or patency capsule testing before VCE in patients with established CD.(6)
The unique ability of VCE to visualize the entire small bowel, its excellent safety profile and tolerability, and its non-invasive nature have already made VCE a valuable diagnostic and monitoring tool for small-bowel CD. Future technologic and clinical advances are likely to increase the utility of this underused tool. Existing and potential applications in IBD include the following:(7)
The major factor limiting broader use of VCE in both clinical practice and research in IBD is the lack of a validated quantitative score to assess mucosal healing and postoperative recurrence.(7) Routine use of VCE could allow more accurate assessment of small-bowel inflammation in IBD.
Special Edition IBD Dialogue 2016 Volume 02: Treat-to-Target in IBD is made possible by an unrestricted educational grant from…