Occult: bleeding that is not visible or hidden and is manifested by positive fecal occult blood testing or iron deficiency anemia

Obscure: clinically observable bleeding with a negative standard evaluation, including: EGD, Colonoscopy, SBS, etc.

Gastrointestinal stromal tumors, leiomyomas, leiomyosarcomas cause >50% of bleeding neoplasms of small intestine

Angiodysplasia (AVMs) or Osler-Weber-Rendu syndrome (OWR)

Dieulafoy’s lesions

Cameron’s erosions (associated with large hiatal hernias)

GAVE (gastric antral vascular ectasia or “watermelon stomach”)

Nonesophageal varices

Portal hypertensive gastropathy

Crohn’s disease

Small bowel erosions, IBD or tumors (i.e. lymphoma, leiomyoma, carcinoid)