Running Can Kill! A Brief Synopsis of AFP's "Evaluation of Occult Gastrointestinal Bleeding"

This is a brief synopsis of 

Evaluation of Occult Gastrointestinal Bleeding

BULL-HENRY K, AL-KAWAS FH 

March 15 2013 Vol. 87 No. 6

http://www.aafp.org/afp/2013/0315/p430.html

     Occult GI bleeding can occur anywhere in the GI tract. Upper tract and small bowel often cause iron deficiency anemia. The other reason to suspect occult bleeding is though FOBT (the o stands for "occult"). Causes of occult upper tract bleeding include esophagitis, ulcers, vascular ectasias, cancer, and Cameron ulcers (linear ulcers from a hiatal hernia). Lower tract bleeding causes include, cancer, polyps, and ectasias.

     The most common cause of occult bleeding in patients younger than 40 are small bowel tumors, celiac, and crohn's disease. In patients older than 40, its vascular ectasias and NSAIDs. A less common cause is through transient intestinal ischemia from long distance running. 

     A thorough history is important when GI bleeding is suspected. Unintentional weight loss,  medications (aspirin, NSAIDs, anticoagulants) and family history could be strong clues. Patients with a history of gastric bypass may have iron absorption issues. On the physical exam, look for dermatitis herpetiformis in celiac disease, erythema nodosum in Crohn disease  spoon nails in Plummer-Vinson syndrome, lip and mouth freckles in Peutz-Jeghers syndrome, or hyperextensible joints in Ehlers-Danlos syndrome. 

     This article does a great job in determining which test to use to find the bleed. If its upper GI, then go with EGD. If its proximal small bowel, then push enteroscopy can be used. It may make more sense to go with the deep enteroscopy because is can also see the mid and distal small bowel. Bleeding in the small bowel can also be seen with capsule endoscopy or CT enteroscopy. Lower tract can be seen with colonoscopy. Barium studies aren't that useful these days.

     There are two algorithms in this article. The first one says that if there is a positive FOBT without iron deficiency anemia, perform a colonoscopy. An EGD should additionally be preformed if there are any upper tract symptoms. The second algorithm is for iron deficiency anemia. All patients with iron deficiency anemia should get a colonoscopy and EGD because GI blood loss should be considered the cause unless otherwise proven. If negative, capsule endoscopy should be done. If negative, the test can be repeated or CT enteroscopy may be performed. If any of these tests come back with positive findings, the patient can be treated accordingly.