Clinical outcomes of negative small-bowel capsule endoscopy for small-bowel bleeding: a systematic review and...

Small-bowel bleeding is the primary indication for capsule endoscopy (CE). Many experts advocate a "watch-and-wait" policy in negative CE. This meta-analysis examines the odds of rebleeding after negative index CE and the impact on long-term follow-up.

A comprehensive literature search identified articles examining the rebleeding rate after negative CE. Demographic and clinical information with emphasis on outcomes was retrieved, pooled, and analyzed. Heterogeneity among studies was assessed using the I² statistic. A random effects model was used as the pooling method because of high heterogeneity. Risk of bias was assessed using the quality assessment of diagnostic accuracy studies (QUADAS-2) tool. The primary outcome evaluated was the pooled odds ratios (ORs) for rebleeding after a negative CE for obscure GI bleeding (OGIB).

Twenty-six studies with 3657 patients were included. The pooled rate of rebleeding after negative CE was .19 (95% CI, .14-.25; P < .0001). The pooled OR of rebleeding was .59 (95% CI, .37-.95; P < .001). The effect was more pronounced in studies with a short follow-up (OR, .47; 95% CI, .24-.94; P < .001). There was no statistically significant difference in rebleeding after CE for occult and overt OGIB. Prospective studies showed a lower OR of rebleeding of .24 (95% CI, .08-.73; P = .01). Most studies were high quality.

Our analysis shows that negative CE provides adequate evidence of a subsequently low risk of rebleeding. Such patients can therefore be safely managed with watchful waiting. However, patients who rebleed after 2 years may need to be investigated for a new source of blood loss.