What is gastrointestinal (GI) bleeding?
Gastointestinal (GI) bleeding describes any blood loss that occurs through the digestive tract. Since the digestive tract begins with the mouth and ends with the anus, GI bleeding can emanate from any site along the way. Doctors often divide digestive tract bleeding into upper GI tract bleeding, lower GI bleeding or occult GI bleeding.
Upper GI bleeding originates in the first part of the GI tract - the esophagus, stomach, or duodenum (first part of the intestine). Bleeding can come from ingestion of caustic poisons or stomach cancer. Lower GI bleeding involves bleeding from the colon and the distal part of the small intestine. When an individual passes bright red blood in the stool, it is usually from the colon, or large intestine, which is the last part of the digestive tract. The rectum is the final segment of the colon just above the anus.
Bleeding may occur anywhere along the digestive tract, from the mouth to the anus, for a variety of reasons. Blood may be visible in the stool or in vomit or may be hidden (occult) and detectable only by diagnostic tests. Bleeding in the GI tract is a symptom of digestive problems rather than a disease itself. Bleeding can occur as the result of a number of conditions, most of which are not life-threatening. Most causes of bleeding are related to conditions that can be cured or controlled. Although the cause of bleeding may not be serious, it is important to locate the source so that the bleeding can be eliminated and the anxiety associated with the uncertainty can be put to rest. Of course, some causes of GI bleeding discussed below are more serious and chronic occult blood loss can produce significant anemia (low red blood cells in blood), which results in other medical problems.