gastrointestinal
Meaning of gastrointestinal: Roots pointing at stomach and intestine, yet the label in practice stretches from mouth to anus and turns up throughout medical records.
Definition of gastrointestinal
Gastrointestinal, usually shortened to GI, means relating to the digestive tube and the organs along it. The word is built from the roots for stomach and intestine, but in ordinary medical use it covers the whole passage from the mouth to the anus. It appears constantly in phrases such as GI bleeding, GI symptoms, and upper GI endoscopy.
What does the gastrointestinal tract include?
The gastrointestinal tract is a single continuous tube. It starts at the mouth and runs through the throat, the esophagus, the stomach, the small intestine, and the large intestine, ending at the rectum and anus. The liver, gallbladder and pancreas are counted as part of the digestive system but not as part of the tube itself. They sit alongside it and empty their secretions into it, which is why a blocked bile duct produces gut symptoms without any disease of the bowel wall.
Where do upper and lower GI divide?
| Upper GI | Lower GI | |
|---|---|---|
| Covers | Esophagus, stomach, first part of small intestine | Rest of the small intestine, colon, rectum |
| Usual examination | Endoscope passed through the mouth | Colonoscope passed through the anus |
| Sign of bleeding | Vomit resembling coffee grounds, black tarry stool | Red or maroon blood mixed with stool |
The dividing landmark is a ligament in the upper abdomen where the duodenum joins the jejunum. Blood that enters above it is exposed to acid and digestive enzymes on its way down, which turns it black. Blood entering lower has a shorter journey and stays red, so the color of the bleeding narrows down the level before any test is done.
Why does one problem cause symptoms elsewhere?
Because the tract is continuous and muscular, trouble at one point backs up or spills forward. A blockage in the small intestine causes vomiting even though the stomach is normal. Inflammation anywhere along the tube can bring nausea, cramping pain, and a change in bowel habit. The nerves supplying the gut are also shared and poorly localized, so pain from the intestines is often felt in the middle of the abdomen rather than directly over the affected segment, which is one reason gut symptoms alone rarely identify the site of the problem.
Also known as
Used in a sentence
The consultation was requested to evaluate the patient's gastrointestinal symptoms of nausea and abdominal pain.
Good to know
The roots of gastrointestinal point only at the stomach and intestines, but clinical usage places the esophagus inside the tract, which is why an upper GI endoscopy examines the esophagus as well as the stomach.
Word origin
Where “gastrointestinal” comes from
Formed from gastro-, from Greek gaster, meaning stomach, and intestinal, from Latin intestinum, meaning gut or intestine.