Published online Aug 21, 2019. doi: 10.3748/wjg.v25.i31.4534
Peer-review started: March 26, 2019
First decision: April 11, 2019
Revised: May 28, 2019
Accepted: July 19, 2019
Article in press: July 19, 2019
Published online: August 21, 2019
Processing time: 148 Days and 14.3 Hours
Crohn’s disease (CD) may affect any part of the digestive tract. Proximal small bowel (SB) lesions, especially jejunal lesions, are associated with an increased risk of stricturing disease and abdominal surgeries compared to esophagogastroduodenal or ileocolonic disease. Thus, assessing the SB may have a significant impact on prognosis. The treat-to-target paradigm was developed in 2015 because of the poor correlation that exists between symptoms and endoscopic disease activity in patients with CD. This concept is based on regular and objective assessment of disease activity and subsequent adjustment of treatment, with the final aim of reaching both clinical and endoscopic remission. Until now, the treat-to-target strategy is based on the assessment of mucosal lesions seen by endoscopy into the ileum and the colon and for the SB by trans-sectional imaging techniques.
The small bowel capsule endoscopy (SBCE) has a higher diagnostic yield compared to the imaging techniques such as the magnetic resonance imaging with enterography (MRE) to detect mucosal lesions especially for the proximal part of the SB and might be more accurate in a treat-to-target strategy. SBCE and MRE are probably complementary, as MRE assesses transmural involvement, while SBCE allows a direct visualization of the mucosal surface of the entire SB. However, there is no recommendation regarding the use of SBCE during patient follow-up.
To investigate the impact of SBCE in a treat-to-target strategy in patients with CD.
An electronic search of the literature was conducted using PubMed and Cochrane library focusing on studies regarding SBCE in the tight monitoring of patients with CD. All articles containing information about SBCE in the context of treat-to-target strategy in patients with CD were included. Full-text articles were retrieved, reference lists were screened manually to identify additional studies.
Forty-seven articles were included in total. Twenty-two studies demonstrated the usefulness of SBCE on disease reclassification of patients suspected or diagnosed with CD, with a significant incremental diagnostic yield compared to other diagnostic modalities. Nine studies showed that mucosal healing can be evaluated by SBCE to monitor the effect of medical treatment. Seven studies demonstrated that SBCE could detect post-operative recurrence to a similar extent as ileocolonoscopy, and proximal SB lesions beyond the reach of the colonoscope in more than half of the patients.
This systematic review provided a global overview of the published studies assessing the use of SBCE in the tight monitoring of patients with CD. SBCE might be incorporated in the treat-to-target algorithm and could be useful for refining disease location and prognosis, assessing mucosal healing in patients under treatment, and monitoring patients in the post-operative setting.
Randomized controlled trials are required to confirm the reliability of SBCE in the treat-to-target algorithm of patients with CD. In addition, the development of pan-enteric video capsule endoscopy should allow to broaden its indications, all the more so as artificial intelligence is expected to help reduce the burden of capsule endoscopists by automatically detecting and classifying lesions.