Should capsule endoscopy be the first test for every obscure gastrointestinal bleeding?

Obscure gastrointestinal bleeding (OGIB) refers to gastrointestinal (GI) bleeding of unclear origin that persists or recurs after negative findings on esophagogastroduodenoscopy and colonoscopy. OGIB accounts for approximately 5% of all types of GI bleeding. More than 80% of OGIB cases originate in the small bowel. The ability to detect OGIB in the small bowel has significantly advanced and been revolutionized since the introduction of the capsule endoscopy and double-balloon enteroscopy techniques in 2000 and 2001, respectively. With these new methods for small-bowel evaluation, new guidelines have been proposed for the diagnosis and management of OGIB. However, some issues remain unsolved. The purpose of this article is to review the various modalities used for evaluating OGIB, including capsule endoscopy and double-balloon enteroscopy, and to help guide clinicians in their decisions on which modality will be the most effective.