Obscure gastrointestinal bleeding and iron-deficiency anemia-Where does capsule endoscopy fit?

The evaluation of patients with obscure gastrointestinal bleeding (OGIB) and iron-deficiency anemia (IDA) has been suboptimal for a long time, mainly owing to the limitations of techniques for the study of the small bowel. Since the introduction of capsule endoscopy (CE) and device-assisted enteroscopy (DAE), the diagnostic and therapeutic approaches to OGIB have improved significantly. CE allows the evaluation of the entire small bowel mucosa, providing high-quality images and identifying mucosal changes (ie, vascular malformations, inflammatory changes, mass, or polyps), whereas DAE ensures an effective therapeutic approach. Many studies have shown that the diagnostic yield (DY) of CE in patients with OGIB and IDA (~50%) is similar to that of DAE and significantly superior to the DY of other imaging modalities for the small bowel. Nowadays, CE is considered the examination of choice in patients with OGIB or IDA, after negative gastroscopy and ileocolonoscopy results. The DY of CE is increased in patients with overt bleeding, or when the procedure is performed closely to an acute episode of bleeding, as well as in patients with severe IDA or high transfusion requirement. CE is also an effective tool in directing further diagnostic or therapeutic interventions (ie, deciding the optimal insertion route of DAE). Moreover, numerous studies have also shown that CE-based strategies affect the management of patients with OGIB.