Indications and detection, completion, and retention rates of small-bowel capsule endoscopy: a systematic review

Background Capsule endoscopy (CE) has been widely used in clinical practice. Objective To provide systematically pooled results on the indications and detection, completion, and retention rates of small-bowel CE. Design A systematic review. Main Outcome Measurements We searched the PubMed database (2000-2008) for original articles relevant to small-bowel CE for the evaluation of patients with small-bowel signs and symptoms. Data on the total number of capsule procedures, the distribution of different indications for the procedures, the percentages of procedures with positive detection (detection rate), complete examination (completion rate), or capsule retention (retention rate) were extracted and/or calculated, respectively. In addition, the detection, completion, and retention rates were also extracted and/or calculated in relation to indications such as obscure GI bleeding (OGIB), definite or suspected Crohn's disease (CD), and neoplastic lesions. Results A total of 227 English-language original articles involving 22,840 procedures were included. OGIB was the most common indication (66.0%), followed by the indication of only clinical symptoms reported (10.6%), and definite or suspected CD (10.4%). The pooled detection rates were 59.4%; 60.5%, 55.3%, and 55.9%, respectively, for overall, OGIB, CD, and neoplastic lesions. Angiodysplasia was the most common reason (50.0%) for OGIB. The pooled completion rate was 83.5%, with the rates being 83.6%, 85.4%, and 84.2%, respectively, for the 3 indications. The pooled retention rates were 1.4%, 1.2%, 2.6%, and 2.1%, respectively, for overall and the 3 indications. Limitations Inclusion and exclusion criteria were loosely defined. Conclusions The pooled detection, completion, and retention rates are acceptable for total procedures. OGIB is the most common indication for small-bowel CE, with a high detection rate and low retention rate. In addition, angiodysplasia is the most common finding in patients with OGIB. A relatively high retention rate is associated with definite or suspected CD and neoplasms.