D

Dehydration
Pronounced – DEE-hy-DRAY-shuhn
Excessive loss of water from the body or from an organ or body part, as from illness or fluid deprivation.

Demyelination
Damage caused to myelin by recurrent attacks of inflammation. Demyelination ultimately results in nervous system scars, called plaques, which interrupt communications between the nerves and the rest of the body.

Diabetes
Pronounced – dye-a-BEE-teez
A disease in which the body does not properly control the amount of sugar in the blood. As a result, the level of sugar in the blood is too high. This disease occurs when the body does not produce enough insulin or does not use it properly.

Diagnosis
The act or process of identifying or determining the nature and cause of a disease or injury through evaluation of patient history, examination, and review of laboratory data.

Diaphragm
Pronounced – DY-uh-fram
The muscle wall between the chest and the abdomen. It is the major muscle that the body uses for breathing.

Diarrhea
Pronounced – DY-uh-REE-uh
Frequent, loose, and watery bowel movements. Common causes include gastrointestinal infections, irritable bowel syndrome, medicines, and malabsorption.

Digestion
Pronounced – dy-JES-tchun
The process the body uses to break down food into simple substances for energy, growth, and cell repair.

Digestive System
Pronounced – dy-JES-tuv sis-tum
The organs in the body that break down and absorb food. Organs that make up the digestive system are the mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus. Organs that help with digestion but are not part of the digestive tract are the tongue, glands in the mouth that make saliva, pancreas, liver, and gallbladder.

Digestive Tract
Pronounced – dy-JES-tuv trakt
The large, muscular tube that extends from the mouth to the anus, where the movement of muscles and release of hormones and enzymes digest food. Also called the Gastrointestinal (GI) Tract or alimentary canal.

Dilatation
The process of enlargement or expansion.

Diverticulitis
Pronounced – DY-vur-TIK-yoo-LY-tiss
Diverticulitis is inflammation of one or more pouches or sacs that bulge out from the wall of a hollow organ, such as the colon. Symptoms include muscle spasms and cramps in the abdomen. The condition of having diverticulitis is called diverticulosis, pronunciation – DY-vur-TIK-yoo-LOH-siss. Diverticulosis and diverticulitis are also called diverticular disease, pronunciation – DY-vur-TIK-yoo-lur.

Diverticulosis
Pronounced – DY-ver-TIH- kyoo-LOH-sis
Diverticulosis is a condition in which little sacs or out pouchings called diverticula develop in the wall of the colon. These sacs tend to appear and increase in number with age. The majority of Americans over age 60 have diverticulosis, but only a small percentage have symptoms or complications. Most people have no symptoms and learn that they have diverticula after an x-ray or intestinal examination. Less than 10 percent of people with diverticulosis ever develop complications such as infection (diverticulitis), bleeding, or perforation of the colon.

Diverticulum
Pronounced – DY-ver-TIH-kyoo-lum
Diverticulum is a small pouch or sac that bulges out from the wall of a hollow organ, such as the colon. Pouches (plural) are called diverticula, pronunciation – DY-vur-TIK-yoo-luh. The condition of having diverticula is called diverticulosis, pronunciation – DY-vur-TIK-yoo-LOH-siss.

Duodenal Ulcer
Pronounced – doo-AW-duh-nul UL-sur
An ulcer in the lining of the duodenum. The duodenum is the first part of the small intestine.

Duodenum
Pronounced – doo-AW-duh-num
The first part of the small intestine, right after your stomach.

Dyspepsia
Pronounced – dis-PEP-see-uh
Poor digestion. Symptoms include heartburn, nausea, bloating, and gas. Also called indigestion.

Dysphagia
Pronounced – dis-FAY-jee-uh
Problems in swallowing food or liquid, usually caused by blockage or injury to the esophagus.