II. Causes: False Positive
III. Causes: Occult Upper Gastrointestinal Bleeding (29-56%)
- See Upper Gastrointestinal Bleeding
- Erosive Gastritis (3-16%)
- Gastric Ulcer (4-6%)
- Gastric Carcinoma or Esophageal Cancer (1-4%)
- Esophageal Varices
- Gastroesophageal Reflux or Esophagitis (6-18%)
- Hiatal Hernia (with Cameron's Erosions)
- Gastric Vascular Malformation or Angiodysplasia (1-8%)
- Dieulafoy's Lesion (dilated vessel in mucosal lesion)
- Antral vascular ectasia (Watermelon Stomach)
IV. Causes: Occult Small Intestinal Bleeding (29-52%)
- See Small Intestinal Bleeding
- Duodenal Ulcer or Duodenitis (1-11%)
- Meckel's Diverticulum
- Crohn's Disease (especially terminal ileum)
- Gluten Enteropathy or Celiac Sprue (0-6%)
- Long Distance Running
V. Causes: Occult Lower Gastrointestinal Bleeding (20-30%)
- See Lower Gastrointestinal Bleeding
- Intestinal Polyps or adenomas that are typically >1 to 1.5 cm (5-14%)
- Colon Cancer (5-11%)
- Angiodysplasia (1-9%)
- Colitis (1-2%)
- Diverticular Bleeding
VI. Causes: Bleeding from a rectal source
VII. Causes: Miscellaneous Source
- Infection
- Amebiasis
- Ascariasis
- Cytomegalovirus
- Hookworm
- Strongyloides
- Tuberculosis (Tuberculous Enterocolitis)
- Whipworm
- Malignancy
- Vascular
- Aortoenteric Fistula
- Hemangioma
- Radiation Injury
- Vascular ectasia
VIII. References
- Rockey in Feldman (2002) Sleisenger GI, p. 232-48
- Bull-Henry (2013) Am Fam Physician 87(6): 430-6 [PubMed]
- Rockey (2010) Nat Rev Gastroenterol Hepatol 7(5): 265-79 [PubMed]
- Zuckerman (2000) Gastroenterology 118:211-2 [PubMed]