CT enterography in obscure gastrointestinal bleeding: a systematic review and meta-analysis

The objective of this article is to provide a comprehensive and update overview of clinical application of CT enterography (CTE) in the evaluation of obscure gastrointestinal bleeding (OGIB). We performed a systematic review of relevant literatures in PubMed, EMBASE and The Cochrane Library and pooled the yield of CTE and the incremental yield (IY) of CTE over an alternate modality. A total of 18 studies (n = 660) reported the yield of CTE in evaluating OGIB and the pooled yield was 40% (95% confidence interval (CI): 33-49%). Seven studies (n = 279) compared the yield of CTE with capsule endoscopy (CE). The yield for CTE and CE for all findings was 34% and 53%, respectively (IY = -19%, 95% CI = -34% to -4%). When considering the types of identified lesions, the yield was significantly different for vascular and inflammatory lesions but not significantly different for neoplastic or other lesions. Two studies (n = 63) compared the yield of CTE with double-balloon enteroscopy (DBE). The yield for CTE and DBE was 38% and 78%, respectively (IY = -40%, 95% CI = -55% to -25%). Three studies (n = 49) compared the yield of CTE with digital subtraction angiography. The yield for CTE and digital subtraction angiography was 64% and 60%, respectively (IY = 4%, 95% CI = -40% to 47%). CTE is an excellent diagnostic tool in patients with OGIB. It may play a complementary role to CE and can be used as a triage tool prior to DBE in evaluating OGIB.