Gastrointestinal bleeding: Clinical

Gastrointestinal bleeding can be divided into upper and lower GI bleeding.

Upper GI bleeding arises above the ligament of Treitz- also called the suspensory ligament of the duodenum- and it includes bleeding from the esophagus, stomach, or duodenum.

Common causes of upper GI bleeding include peptic ulcer disease, erosive esophagitis, esophageal varices, an arteriovenous malformation or an AVM, Mallory-Weiss syndrome and cancers of the upper GI tract.

Lower GI bleeding arises below the ligament of Treitz and includes bleeding from the small intestines past the ligament of Treitz, large intestines, rectum, and anus.

Common causes of lower GI bleeding include diverticulosis, hemorrhoids, colorectal cancer, AVMs, and intestinal ischemia.

Now, both upper and lower GI bleedings can be either visible or occult- meaning that there’s no visible evidence of bleeding. This is usually detected by a fecal occult blood test or if there are signs of iron deficiency anemia.

Okay, first things first. A visible upper GI bleed causes hematemesis- which is vomiting of blood, and suggests moderate to severe ongoing bleeding.

If the blood looks like coffee-grounds - it suggests that the blood has been oxidized by acid in the stomach so that the iron in the blood has turned black. It’s a sign that bleeding was a small quantity or has stopped.

Melena refers to black and tarry stools, and that most often result from upper GI bleeding. In fact, it takes about 50 milliliters of blood in the stomach to turn the stools black.

A lower GI bleeding can cause hematochezia- which is fresh blood passing through the anus which may or may not be mixed with stool.