Obscure Gastrointestinal Bleeding

Elderly (>65 years) Middle‐Aged (41‐65 years) Young Adult (17‐40 years) Vascular anomalies Small intestinal ulcer NSAID enteropathy Small intestinal tumours Non‐specific enteritis Vascular anomalies Small intestinal tumours Non‐specific enteritis Small intestinal ulcer Crohn’s disease Small intestinal tumours Meckel’s diverticulum Non‐specific enteritis Dieulafoy’s lesion Vascular anomalies Table 1. Etiology of Obscure Gastro‐intestinal Bleeding According to Age Introduction In last decade, the availability of advanced diagnostic innovations like capsule endoscopy (CE) and balloon‐assisted enteroscopy (BAE) have led to reclassification of gastrointestinal (GI) bleeding into three categories: upper‐, mid‐ and lower GI bleeding. If the source of GI bleeding is between the ampulla of Vater and the terminal ileum, it is designated as mid‐GI bleeding. Of total GI bleeding, it is estimated that upper GI bleeding (from the esophagus to duodenum 2 portion), lower GI bleeding (from the colon and anorectum) and mid GI bleeding account, respectively, for 50%, 40% and 10%. Obscure gastrointestinal bleeding (OGIB) is defined as occult or overt bleeding of unknown origin that persists or recurs after an initial negative endoscopic evaluation including colonoscopy and EGD. Overt OGIB is defined as visible GI bleeding (eg, melena or hematochezia) and can be categorized further as active (ie, evidence of ongoing bleeding) versus inactive bleeding. In this review, we will discuss the etiology and current diagnostic approach focused on the CE and BAE in patients with OGIB.