Play 0:00 A-CD-HI-MN-Z A-C Return to top Abdomen (abdominal cavity) The part of the body between the chest and the pelvis. Aberrant pancreas (pancreatic rest; heterotopic pancreas; ectopic pancreas) A type of submucosal nodule in which pancreatic tissue develops under the lining, or mucosa, of another organ, such as the stomach or small intestine. Abscess A swollen, pus-filled pocket of infection. Acetaminophen Medication used as a pain reliever and fever reducer. Achalasia A condition in which the muscles of the lower part of the esophagus fail to relax, preventing food from passing into the stomach. Acid indigestion Another name for gastroesophageal reflux (GER). Acid reflux Another name for gastroesophageal reflux (GER). Acid regurgitation Another name for gastroesophageal reflux (GER). Acute Symptoms or conditions that are short-term. Adenocarcinoma A type of cancer that forms in the glandular cells that produce and release mucus and other fluids. Adenoma A type of polyp that has the potential to become cancerous. Adenovirus One of a group of viruses that can cause infections of the lung, stomach, intestine, and eyes. Adhesions Fibrous bands of scar tissue that form between internal organs and tissues, joining them together abnormally. Adjuvant therapy Chemotherapy, radiation therapy, or chemoradiation therapy given after surgery to lower the risk that cancer will return. Adrenal glands Endocrine glands found above the kidneys that produce a variety of hormones, including adrenaline, aldosterone, and cortisol. Aflatoxin B1 A poisonous carcinogen produced by the Aspergillus flavus and Aspergillus parasiticus molds that commonly contaminates a variety of foods. Alagille syndrome A genetic disorder that can result in liver damage caused by abnormalities in the bile ducts. Albumin The main protein in human blood. Alcoholic liver disease Liver damage that results from heavy alcohol consumption over a number of years. Alcoholism An addiction to the consumption of alcohol or the mental illness and compulsive behavior resulting from alcohol dependency. Allergens Substances that cause an allergic reaction. Allergic rhinitis Also known as hay fever, a type of inflammation in the nose which occurs when the immune system overreacts to allergens in the air. Alpha-fetoprotein (AFP) A protein produced normally by the liver of a fetus, but present abnormally in adults with some cancers. Aminosalicylates Anti-inflammatory medications used to treat inflammatory bowel disease (IBD) and some forms of arthritis. Amoxicillin A broad-spectrum antibiotic used to treat bacterial infections, especially ear and upper respiratory infections. Ampulla of Vater Also known as the hepatopancreatic ampulla or hepatopancreatic duct, formed by the union of the pancreatic duct and the common bile duct. Anal electromyography (EMG) A procedure that uses electrodes to measure the electrical activity of anal muscles. Anal fissure A small tear in the lining (mucosa) of the anus. Anal manometry A procedure used to evaluate anal sphincter muscles and rectal sensation. Analgesics Medications used for pain relief. Anastomosis A connection made surgically between adjacent blood vessels, parts of the intestine, or other channels of the body. Anemia A condition in which a person does not have enough healthy red blood cells. Anemia of chronic disease (ACD) Anemia that results from certain chronic medical conditions that involve inflammation. Anesthesia A state of temporary induced loss of sensation (local) or awareness (general). Angiodysplasia The presence of swollen, fragile blood vessels in the gut. Angiogenesis inhibitors Medications that block the growth of new blood vessels. Angiography A procedure used to view blood vessels after injecting them with a special dye that outlines them on x-rays. Anorectal ultrasound (endorectal ultrasound) A procedure in which an ultrasound probe is inserted into the rectum, and high-frequency sound waves are used to create an image of surrounding tissues. Antacids Medications that help neutralize stomach acid. Antibiotics Medications that fight bacterial infections. Antibodies Blood proteins produced in response to and counteracting a specific antigen, such as bacteria, viruses, and other foreign substances. Antidepressants Medications prescribed to treat depression. Antihistamines Medications that treat allergic rhinitis and other allergies. Antihypertensives Medication used to lower high blood pressure. Antimotility agent Medications used to inhibit or slow gastrointestinal motility in order to treat diarrhea. Anti-rejection medication Medication used to prevent organ or tissue transplant rejection. Antispasmodics Medications used to relieve spasm of involuntary muscle. Antiviral medications Medications that fight viral infections. Anus The final part of the digestive tract, an opening through which stool passes out of the body. Anxiety A feeling of nervousness, stress, or apprehension. Anxiety disorder is diagnosed when these feelings persist for several months. Appendicitis A serious medical condition in which the appendix becomes inflamed and painful. Ascending colon The second part of the large intestine, between the cecum and the transverse colon, that travels up the right side of the abdomen. Ascites An abnormal accumulation of fluid in the abdomen. Aspergillus flavus A fungus that commonly colonizes in cereal grains, legumes, and tree nuts. Aspiration The accidental breathing of food or other matter into the lungs. Asthma A respiratory condition in which the airways become inflamed and produce extra mucus. Autoimmune disorder (autoimmune disease) A disorder or disease in which the body produces antibodies that attack its own tissues. Autoimmune hepatitis A condition in which the immune system attacks liver cells, which eventually causes cirrhosis and liver failure. Autoimmune reaction An immune response against in which antibodies and immune cells attack the body's own healthy cells and tissues. Autosomal dominant pattern A pattern of genetic inheritance in which an affected individual has one copy of a mutant gene and one normal gene on a pair of autosomal chromosomes. Bacillary dysentery A severe form of Shigellosis, or infection from shigella bacteria. Bacteria Microscopic, single-celled organisms that can cause infection. Bacterial endocarditis Inflammation of the inner tissues of the heart caused by bacterial infection. Balloon dilatation A procedure in which an endoscope with a small balloon is used to dilate, or stretch, a narrowed bile duct. Balloon expulsion test A procedure which measures how long it takes a person to push a water-filled balloon out of their rectum. Barium A chalky liquid solution that is used as a contrast agent in gastrointestinal x-ray studies. Barium enema (lower GI series) A procedure that uses x-rays and a chalky liquid called barium to view the lower GI tract, including the colon and the rectum. Barium swallow (upper GI series) A procedure that uses x-rays and a chalky liquid called barium to view the upper GI tract, including the esophagus, stomach, and first part of the small intestine (duodenum). Barrett's esophagus A condition in which the normal tissue lining the esophagus changes to tissue that resembles the lining of the intestine. Benign A descriptive term for conditions that present no danger to life or well-being. Beta-blocker Medications used to control heart rhythm, treat angina (chest pain), and reduce high blood pressure. Bile The digestive juice secreted by the liver and stored in the gallbladder, responsible for digesting fats. It is made up of cholesterol, bilirubin, and bile salts. Bile ducts Passageways that carry bile from the liver to the gallbladder and small intestine. Bile salts Any of the sodium salts found in bile acid. Biliary bypass A surgical procedure in which the part of the bile duct before the blockage is connected with part of the bile duct that is past the blockage or to the small intestine. Biliary stones Gallstones that travel into the bile ducts and become lodged there. Biliary stricture A narrowing of a bile duct. Biliary tree The system of bile ducts that carry bile from the liver to the gallbladder and small intestine. Bilirubin An orange-yellow pigment formed in the liver by the breakdown of hemoglobin and excreted in bile. Biofeedback A training technique by which a person learns how to regulate certain body functions. Biologics Medications produced from living organisms or containing components of living organisms. Biopsy An examination of tissue removed from the body to discover the presence, cause, or extent of a disease. Bismuth subsalicylates Medications that coat ulcers and protect them from stomach acid. Bloating Abnormal gas swelling of the abdominal area. Botulinum toxin A medication made from a toxin produced by the bacterium Clostridium botulinum, which works by weakening or paralyzing certain muscles or by blocking certain nerves. Bowel Refers to one of the intestines (small or large). Bowel movement The movement of stool as it passes out of the body through the rectum and anus. Bowel obstruction (obstruction; intestinal obstruction) A blockage of the small intestine or the large intestine that prevents the normal movement of the products of digestion. Bowel prep Preparation for a procedure, such as colonoscopy, in which the intestines are cleansed of fecal matter and secretions. Bowel rest The intentional restriction of food and drink in order to allow the bowel to rest and heal. Brisk bleed Rapid bleeding or escape of blood from a ruptured vessel. Bulking agent Medications used to treat constipation by increasing the volume of stool and making it easier to pass. Calcium channel blockers Medications that prevent calcium from entering cells of the heart and blood vessel walls, resulting in lower blood pressure. Campylobacter A bacterium that causes food poisoning in humans. Capsule endoscopy A procedure that uses a swallowed capsule-like camera to view the lining of the middle part of the GI tract, which includes the three parts of the small intestine -- the duodenum, jejunum, and ileum. Carbohydrates A large group of organic compounds made of carbon, hydrogen, and oxygen, found in certain foods (such as bread, rice, and potatoes) that provide humans and animals with heat and energy. Carcinoid A type of submucosal nodule that has a high potential for being malignant and which grows out of a type of cell found in the GI tract, called enterochromaffin cells, which help regulate gastrointestinal functions. Cataracts A medical condition in which the lens of the eye becomes progressively cloudy, or opaque, resulting in blurred vision. Catheter A flexible tube inserted through a narrow opening into a body cavity for removing or injecting fluid. Cecum The first part of the large intestine, where it attaches to the small intestine. Celiac disease A condition in which an immune reaction triggered by gluten causes damage to the small intestine. Chaparral Vegetation consisting chiefly of tangled shrubs and thorny bushes. Chemoembolization A procedure in which the blood supply to a tumor is blocked so that anticancer drugs can be administered directly into the tumor without spreading to the rest of the body. Chemoradiation A medical treatment that combines chemotherapy and radiation therapy to increase the effects of both. Chemotherapy A medical treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Cholangiocarcinoma A growth of malignant cells in the tissues of the bile ducts. Cholangitis Inflammation of the bile ducts. Cholecystectomy A surgical procedure involving the removal of the gallbladder. Cholecystitis Inflammation of the gallbladder. Cholescintigraphy (HIDA scan) A nuclear imaging study used to evaluate the function of the gallbladder and diagnose obstruction of bile ducts. Cholestasis A condition in which bile cannot flow from the liver to the duodenum. Cholesterol A soft, waxy substance containing a lot of fat that is found in body tissue, blood, and the digestive juice secreted by the liver (bile). Cholesterol stones Yellow-green gallstones made primarily of cholesterol. Chronic Symptoms or conditions that are long-lasting. Chronic fatigue syndrome A disorder characterized by extreme fatigue or tiredness that doesn't go away with rest and can't be explained by an underlying medical condition. Chronic obstructive pulmonary disease (COPD) A lung disease characterized by chronic obstruction of lung airflow that interferes with normal breathing and is not fully reversible. Chyme Food contents that pass from the stomach to the small intestine. Cirrhosis A chronic disease of the liver marked by degeneration of cells, inflammation, and scarring of tissue. Clarithromycin A macrolide antibiotic used to treat bacterial infections of the skin and respiratory system, and in combination with other medications to treat peptic ulcers caused by H. pylori. Clostridium difficile (C. difficile) A bacterium that is one of the most common causes of infection of the colon in the United States. Clotting factor Any of a number of substances in blood plasma that are involved in the clotting process. Colitis Inflammation or infection of the large intestine (colon). Colon (large intestine; large bowel) An organ in the digestive tract, responsible for changing waste from liquid into solid matter called stool. Colon polyps Growths on the lining of the colon and/or rectum. Colonoscopy A procedure that uses a thin, flexible tube with a camera (colonoscope) to view the inside of the entire large intestine, or colon, and rectum. Colorectal cancer A growth of malignant cells in the tissues of the colon or the rectum. Colostomy A surgical procedure in which a piece of the colon is diverted to an artificial opening in the abdominal wall so as to bypass a damaged part of the colon. Coma A state of deep unconsciousness that lasts for a prolonged or indefinite period. Comfrey tea Tea made from a perennial herb with a black, turnip-like root and large, hairy broad leaves. Common bile duct The bile duct that is formed where the common hepatic duct (from the liver) and the cystic duct (from the gallbladder) meet. Common hepatic duct The bile duct that connects the liver to the common bile duct. Computed tomography (CT) colonography (virtual colonoscopy) A procedure that uses a combination of x-rays and computer technology to create multiple high-resolution cross-sectional images of the colon and rectum. Computed tomography (CT) enterography A procedure that uses a combination of x-rays and computer technology to create multiple high-resolution cross-sectional images of the small intestine. Computed tomography (CT) scan A procedure that uses a combination of x-rays and computer technology to create multiple high-resolution cross-sectional images of internal organs and soft tissues. Constipation A condition in which bowel movements are infrequent and stool is hard, dry, and/or difficult to pass. Contrast medium A substance introduced into a part of the body in order to improve the visibility of internal structures during radiologic tests. Corticosteroids Medications used to treat inflammation. Costochondritis An inflammation of the cartilage that connects a rib to the breastbone. COX-1 enzymes A type of cyclooxygenase enzyme that produces chemicals (prostaglandins) that activate platelets and protect the stomach and intestinal lining. COX-2 enzymes A type of cyclooxygenase enzyme that produces chemicals (prostaglandins) that promote inflammation, pain, and fever in response to injury or infection. Crohn's disease A chronic inflammatory disease of the intestines, especially the colon and ileum (last part of the small intestine), that often causes ulcers and fistulas. Cryosurgery (cryotherapy) A type of surgery that uses the local application of intense cold to destroy unwanted tissue. Cryptogenic cirrhosis A condition in which the cause of cirrhosis is unknown. Cryptosporidium A parasite that can cause infection of the intestines. Cyclic vomiting syndrome A chronic functional condition of unknown cause, characterized by recurring attacks or episodes of intense nausea, vomiting, and sometimes abdominal pain, headaches, or migraines. Cyclooxygenase (COX) enzymes Enzymes in the body that produce chemicals (prostaglandins) that promote inflammation, pain, and fever in response to injury or infection. Cyclospora A parasite that can cause gastrointestinal infection. Cystic duct The bile duct that connects the gallbladder to the common bile duct. D-H Return to top Defecography A video x-ray of the area around the anus and rectum. Defecation The discharge of feces from the body. Dehydration A harmful reduction in the amount of water in the body. Depression A mental health disorder characterized by low mood and loss of interest in activities. Descending colon The fourth part of the large intestine, between the transverse colon and the sigmoid colon, that travels down the left side of the abdomen. Desmoid tumor An abnormal growth that arises from connective tissue. Diabetes (diabetes mellitus) A disease in which the body's ability to produce or respond to the hormone insulin is impaired, resulting in elevated levels of glucose in the blood. Diarrhea Bowel movement pattern characterized by loose or watery stools. Digestion The process by which the digestive system breaks down food into nutrients that the body uses for energy, growth, and cell repair. Digestive juices Substances secreted by various organs in the digestive system that break down food into nutrients for the body to use. Digestive system The system of organs in the body that are involved in digestion, which is the breaking down of food into nutrients that the body uses for energy, growth, and cell repair. It includes the digestive tract, the liver, the pancreas, and the gallbladder. Digestive tract (gastrointestinal (GI) tract) The series of hollow organs through which food passes during the digestive process. It includes the mouth, the esophagus, the stomach, the small intestine, the large intestine (colon and rectum), and the anus. Distal extrahepatic bile duct cancer A growth of malignant cells in the tissues of the distal region of the biliary tree. Distal pancreatectomy A surgical procedure involving the removal of the bottom half of the pancreas. Distal region (biliary tree) Region of the biliary tree that includes the common bile duct. Diuretics Medications that rid the body of excess water by causing an increase in urination. Diverticula The plural of diverticulum. Diverticular bleeding A condition in which a diverticulum (small pouch that forms in the wall of the colon) bursts and bleeds. Diverticular disease Symptomatic diverticulosis. Diverticulitis Inflammation of diverticula (small pouches that form in the wall of the colon). Diverticulosis A condition which diverticula (small pouches) form in the wall of the colon without signs of inflammation. Diverticulum A small pouch that forms in the wall of the colon. Duodenum The first part of the small intestine where it attaches to the stomach and receives digestive juices from the liver, gallbladder, and pancreas. Duplication cyst A congenital abnormality that can form under the lining (mucosa) of the GI tract. Dyspepsia Indigestion. Dysphagia A condition in which a person has difficulty swallowing. Ectopic pancreas (pancreatic rest; aberrant pancreas; heterotopic pancreas) A type of submucosal nodule in which pancreatic tissue develops under the lining, or mucosa, of another organ, such as the stomach or small intestine. Ectopic pregnancy A potentially life-threatening condition in which a pregnancy occurs outside the uterus, most often in the fallopian tube. Eczema A medical condition in which patches of skin become rough and inflamed, with blisters that cause itching and bleeding. Edema An abnormal accumulation of fluid in the legs, ankles, and feet. Electrocoagulation A medical treatment that uses an electric current to kill cancer cells. Endoluminal laser therapy A procedure in which an endoscope with a laser attached is inserted into the body to remove cancer and other tissues. Endoluminal stent placement A surgical treatment for tumors blocking the passage into or out of the stomach, in which a stent is inserted into the passage from the esophagus to the stomach or from the stomach to the small intestine. Endometriosis A condition in which the tissue that normally lines the uterus grows in other areas of the body, often causing pain, irregular bleeding, and infertility. Endorectal ultrasound (ERUS) (anorectal ultrasound) A procedure in which an ultrasound probe is inserted into the rectum, and high-frequency sound waves are used to create an image of surrounding tissues. Endoscopic mucosal recection (EMR) The removal of stage I or stage II colorectal cancer with a colonoscope. Endoscopic retrograde cholangiopancreatography (ERCP) A procedure that combines upper GI endoscopy and x-rays to evaluate and treat problems of bile and pancreatic ducts. Endoscopic ultrasound (EUS) A procedure that combines traditional endoscopy with ultrasound to examine the upper and lower GI tract as well as surrounding organs, including the lungs, liver, gallbladder, and pancreas. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) A biopsy procedure used to evaluate submucosal nodules. Endoscopy Any procedure that uses a thin, flexible tube with a camera (endoscope) to look inside the body, but most often refers to an examination of the upper part of the GI tract. End-stage liver disease Another term for liver failure, when the liver can no longer perform important functions or replace damaged cells. Enema A procedure in which liquid or gas is injected into the rectum through the anus. Enterocele A condition in women in which the small intestine protrudes into the area between the rectum and the vagina. Enterochromaffin cells A type of cell found in the small intestine that produces serotonin. Enzyme A substance in the body that breaks down or builds up other molecules. Eosinophil A type of white blood cell that helps protect the body from harmful bacteria and parasites. Eosinophilic esophagitis (EoE) An allergic inflammatory condition in which eosinophils (certain white blood cells) build up in the lining of the esophagus. Erlotinib A medication used to treat several types of cancer, including pancreatic cancer. Escherichia coli (E. coli) A bacterium commonly found in the intestines of humans and other animals, where it usually causes no harm, but some strains that contaminate food and water can cause serious gastrointestinal infection. Esophageal cancer A growth of malignant cells in the tissues of the esophagus. Esophagectomy A surgical procedure to remove part of the esophagus. Esophagitis Inflammation of the esophagus. Esophagus The muscular tube in the digestive tract that carries food from the mouth to the stomach. Exocrine cells Cells in the pancreas that secrete digestive enzymes. External anal sphincter One of two sphincters controlling the closing of the anus. External hemorrhoids Swollen blood vessels near the anal opening. External radiation therapy A medical treatment that uses a machine outside the body to send radiation toward cancer inside the body. Extrahepatic cholangiocarcinoma A growth of malignant cells in the tissues of the bile ducts outside of the liver. Extrinsic compression A protrusion of another organ into the stomach, causing what looks like a submucosal nodule in some imaging tests. Familial adenomatous polyposis (FAP) An inherited genetic condition characterized by cancer of the colon and rectum. Fatigue A feeling of tiredness. Fatty diarrhea (malabsorption diarrhea) Chronic diarrhea that results from the body's inability to absorb nutrients properly or digest food effectively. Fatty liver disease A condition in which there is a buildup of fat in the liver. Fecal immunochemical test (FIT) A type of fecal occult blood test (FOBT) used as a screening test for colon cancer that detects hidden blood in the stool. Fecal impaction A solid, immobile bulk of human feces that can develop in the rectum as a result of chronic constipation. Fecal incontinence The inability to control bowel movements. Fecal occult blood test (FOBT) A stool sample test that detects hidden blood in the stool. Fibrosis The process of the formation of scar tissue. Fistula An abnormal passage between hollow or tubular organs, or between an organ and the outside of the body. Flexible sigmoidoscopy A procedure that uses a thin, flexible tube with a camera (sigmoidoscope) to view the rectum and the lower part of the colon (sigmoid colon). Fluoroscopy A type of medical imaging that shows a continuous x-ray image on a monitor. Fructose intolerance The inability to digest fructose, which is a hexose sugar found especially in honey and fruit. Functional disorder A medical condition that impairs the normal function of a bodily process, but where every part of the body looks completely normal under examination. Fundoplication A type of laparoscopic surgery used to treat GERD in which the top of the stomach is attached around the esophagus to add pressure to the lower esophageal sphincter (LES) and reduce reflux. Gallbladder A small organ in the digestive system, where bile produced by the liver is stored. Gallbladder cancer A growth of malignant cells in the tissues of the gallbladder. Gallstone Hardened collection of cholesterol or bilirubin that form in the gallbladder. Gallstone pancreatitis Inflammation of the pancreas that results from a gallstone blocking the pancreatic duct. Gastric atrophy A condition in which the stomach muscles shrink and become weak. Gastric bypass A surgical procedure in which the stomach is divided into an upper pouch and a lower pouch, and the small intestine is connected to both pouches. Gastric cancer (stomach cancer) A growth of malignant cells in the tissues of the stomach. Gastritis Inflammation of the lining of the stomach. Gastroenteritis Inflammation of the stomach and intestines, typically resulting from bacterial, viral, or parasite infection and causing vomiting and diarrhea. Gastroesophageal reflux (GER) An incident in which stomach contents travel back up into the esophagus, causing heartburn. Gastroesophageal reflux disease (GERD) A long-term condition in which stomach contents travel back up into the esophagus, causing heartburn and other potential symptoms and complications. Gastrointestinal infection A viral, bacterial, or parasite infection that causes gastroenteritis. Gastrointestinal stromal tumor (GIST) A type of submucosal nodule most commonly found in the stomach or small intestine that is thought to grow from specialized cells found in the GI tract called interstitial cells of Cajal (ICCs) or precursors to these cells. Gastrointestinal (GI) tract (digestive tract) The series of hollow organs through which food passes during the digestive process. It includes the mouth, the esophagus, the stomach, the small intestine, the large intestine (colon and rectum), and the anus. Gastrojejunostomy A surgical procedure involving the removal of the part of the stomach with cancer that is blocking the opening into the small intestine. The stomach is connected to the middle part of the intestine (jejunum). Genetic (germline) testing A lab test done using a blood or saliva sample to look for certain gene mutations responsible for inherited genetic disorders. Giardia lamblia A parasite responsible for a contagious form of diarrhea, most commonly transmitted through direct contact with infected feces or by eating food or drinking water contaminated by feces. Glandular cells Cells in the body that produce a secretion. Glucagon A hormone produced in the pancreas that raises the level of glucose in the blood by stimulating the liver to release glucose from glycogen stores. Glucose A simple sugar found in the blood that serves as the body's main source of energy. Gluten A mixture of two proteins found in cereal grains, especially wheat, that is responsible for the elastic texture of dough. Granular cell tumor A type of submucosal nodule most commonly found in the esophagus, but they can also occur in the stomach, colon, rectum, and bile ducts. Guaiac fecal occult blood test (gFOBT) A type of fecal occult blood test (FOBT) used as a screening test for colon cancer that detects hidden blood in the stool. Gut Refers collectively to the small and large intestines. Gut flora (microbiome) Bacteria in the digestive system that help break down food into nutrients for the body to use. H2 blockers (histamine receptor blockers) Medications that decrease stomach acid production by blocking histamine, a chemical in the body that signals the stomach to produce acid. Hamartomatous polyp A benign polyp made up of tissue elements normally found at the site of growth, but which are growing in a disorganized manner. Heartburn A painful, burning sensation in the middle of the chest, behind the breastbone, and in the middle of the abdomen. Helicobacter pylori (H. pylori) A type of bacteria that infects the digestive tract and can cause peptic ulcers. Hemoglobin A red protein responsible for transporting oxygen in the blood. Hemophilia A medical condition in which the ability of the blood to clot is severely reduced. Hemorrhoids Swollen blood vessels in the region of the anus. Hepatic artery The main artery supplying blood to the liver. Hepatic ducts Bile ducts inside the liver. Hepatic encephalopathy An accumulation of toxins in the brain that results from cirrhosis and disrupts mental function. Hepatitis Inflammation or infection of the liver. Hepatitis A Refers to a virus and the infection it causes, which affects the liver and can also cause mild gastroenteritis. Hepatitis B Refers to a virus and the infection it causes, which affects the liver. Hepatitis C Refers to a virus and the infection it causes, which affects the liver. Hepatoblastoma A rare type of liver cancer that can affect young children. Hepatocellular carcinoma A growth of malignant cells in the tissues of the liver. Hepatopulmonary syndrome Lung failure caused by cirrhosis. Hepatorenal syndrome Kidney failure caused by cirrhosis. Hereditary (primary) hemochromatosis A genetic disorder in which there is an overload of iron in the body. Hernia A condition in which part of an organ is displaced and protrudes through the wall of the cavity containing it. Heterotopic pancreas (pancreatic rest; aberrant pancreas; ectopic pancreas) A type of submucosal nodule in which pancreatic tissue develops under the lining, or mucosa, of another organ, such as the stomach or small intestine. HIDA scan (cholescintigraphy) A nuclear imaging study used to evaluate the function of the gallbladder and diagnose obstruction of bile ducts. Hilum region (biliary tree) The region of the biliary tree the includes the common hepatic duct. Histamine A compound that is released by cells in response to injury and in allergic and inflammatory reactions, causing contraction of smooth muscle and dilation of capillaries. HIV A sexually transmitted virus that interferes with the body's ability to fight infection. Hodgkin's disease A malignant but often curable disease of lymphatic tissues typically causing painless enlargement of the lymph nodes, liver, and spleen. Hormone A chemical released by the endocrine glands and other tissues to help control certain functions in the body. Human papillomavirus A group of viruses that includes more than 150 different strains or types, many of which are sexually transmitted. Hyperplastic polyp A benign small sessile polyp. Hypothyroidism A condition in which the thyroid gland does not produce enough thyroid hormone. Hysterectomy A surgical procedure involving removal of the uterus. I-M Return to top Idiosyncratic reaction Drug reactions that occur rarely and unpredictably amongst the population. Ileoanal reservoir (ileoanal anastomosis) A surgical procedure that removes part of the colon and uses the ileum to form a new reservoir for waste that can be expelled through the anus. Ileostomy A surgical procedure in which a piece of the ileum is diverted to an artificial opening in the abdominal wall. Ileum The final part of the small intestine, where it attaches to the large intestine. Immune system The system in the body that works to fight off infection and disease. Immunoglobulin A class of proteins present in the serum and cells of the immune system that function as antibodies. Immunomodulators Medications that help regulate or normalize the immune system. Indigestion Pain or discomfort in the stomach associated with difficulty in digesting food. Inflammation The body's response to injury or infection, which increases blood flow to the affected area and results in redness and warmth. Inflammatory bowel disease (IBD) One of a group of diseases, including Crohn's disease and ulcerative colitis, characterized by chronic inflammation of the GI tract. Inflammatory polyp A benign polyp commonly found in people with an inflammatory bowel disease (IBD). Influenza A highly contagious viral infection of the respiratory passages, commonly called "the flu," which causes fever, severe aching, and excessive discharge or buildup of mucus in the nose or throat. Infrared coagulation A medical procedure used to treat small- and medium-sized hemorrhoids. Ingestion The process of taking food, drink, or another substance into the body by swallowing. Injection sclerotherapy A medical treatment for hemorrhoids, varicose veins, and varices. Insulin A hormone produced in the pancreas that helps cells throughout the body to absorb glucose from the blood to use for energy. Insulin resistance A condition in which the body's cells do not respond normally to insulin, which leads to high blood glucose. Internal anal sphincter One of two sphincters controlling the closing of the anus. Internal hemorrhoids Swollen blood vessels inside the rectum and above the anal opening. Internal radiation therapy A medical treatment that uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near cancer. Intestinal obstruction (obstruction; bowel obstruction) A blockage of the small intestine or the large intestine that prevents the normal movement of the products of digestion. Intrahepatic cholangiocarcinoma A growth of malignant cells in the tissues of the bile ducts inside the liver. Intrinsic factor A substance secreted by the stomach that enables the body to absorb vitamin B12. Iron deficiency anemia A common form of anemia in which the body does not have enough iron. Irritable bowel syndrome (IBS) A group of symptoms, including abdominal pain or discomfort, bloating, and a change in bowel habits (diarrhea, constipation, or both). Irritable bowel syndrome with constipation (IBS-C) Irritable bowel syndrome in which constipation most frequently characterizes bowel habit. Irritable bowel syndrome with diarrhea (IBS-D) Irritable bowel syndrome in which diarrhea most frequently characterizes bowel habit. Ischemia An inadequate blood supply to an organ or part of the body, especially the heart muscles. Jaundice A medical condition with yellowing of the skin or whites of the eyes, arising from excess of the pigment bilirubin and typically caused by obstruction of the bile duct, by liver disease, or by excessive breakdown of red blood cells. Jejunum The middle part of the small intestine. Kava A Polynesian shrub. Kidney dialysis A treatment that filters and purifies blood using a machine when the kidneys are no longer able to do their job. Kidney stone A hard mass formed in the kidneys, typically consisting of insoluble calcium compounds. Klatskin tumor A bile duct cancer occurring in the hilum region of the biliary tree. Lactose intolerance The inability to digest lactose, a component of milk and some other dairy products, due to a lack of an enzyme called lactase in the small intestine. Lactulose A synthetic sugar with laxative properties. Laparoscopy A surgery that uses a thin, lighted tube with a camera (laparoscope) passed through a small cut, or incision, in the skin. Tiny tools are inserted through the laparoscope to perform surgical functions. Large bowel resection A surgical procedure involving the removal of all or part of the large intestine. Large intestine (colon; large bowel) An organ in the digestive tract, responsible for changing waste from liquid into solid matter called stool. Laser therapy A medical treatment that uses a laser beam to kill cancer cells. Laxative A medication used to treat constipation by stimulating evacuation of the bowels. Leiomyoma A benign type of submucosal nodule usually found in the lower section of the esophagus. Lesion An area of abnormal tissue change. Levothyroxine A medication prescribed as a thyroid hormone replacement. Linaclotide A medication used to treat chronic constipation. Lipoma A benign type of submucosal nodule consisting of slow-growing, fatty tissue that generally causes no symptoms and requires no treatment. Listeria A type of bacterium that infects humans and other warm-blooded animals through contaminated food. Liver The largest internal organ in the body, responsible for secreting bile to digest fats, detoxifying chemicals, metabolizing drugs, filtering blood, and producing blood proteins for clotting. Liver cancer A growth of malignant cells in the tissues of the liver. Liver failure The inability of the liver to perform it's normal functions. Liver transplant A surgical procedure in which a diseased liver is removed and replaced with a healthy liver from a deceased donor or part of a liver from a living donor. Local excision A surgical procedure to remove a small area of diseased or problematic tissue. Loperamide An opiate medication that inhibits peristalsis in order to treat diarrhea. Lower esophageal sphincter (LES) A ring of muscle at the lower end of the esophagus that allows food into the stomach and keeps stomach contents from coming back up. Lower gastrointestinal (GI) series (barium enema) A procedure that uses x-rays and a chalky liquid called barium to view the lower GI tract, including the colon and the rectum. Lubiprostone A medication prescribed to treat chronic constipation and opioid-induced constipation. Lumen The inside space of a tubular structure, such as an artery or intestine. Lymph nodes Small bean-shaped structures located throughout the lymphatic system that contain lymphocytes (white blood cells), which help the body fight infection and disease. Lymphoma Cancer of the lymph nodes. Lynch syndrome A genetic condition that greatly increases the risk of colon cancer, as well as other cancers. Macrolide antibiotic A class of antibiotic medications that are especially effective against gram-positive bacteria, such as Staphylococci and Streptococci. Magnetic resonance cholangiopancreatography (MRCP) A type of MRI used to evaluate the bile ducts and pancreas. Magnetic resonance (MR) enterography A type of MRI used to evaluate the small intestine. Magnetic resonance imaging (MRI) A procedure that uses a combination of radio waves and magnets to create images of internal organs and soft tissues. Malignant Cancer that tends to invade and destroy nearby tissue and possibly spread (metastasize) to other parts of the body. Mallory-Weiss tear A tear in the mucosal lining of the esophagus caused by forceful vomiting or retching. Measles An infectious viral disease causing fever and a red rash on the skin. Medication-induced liver injury Damage to the liver caused by medication. Mesalazine An aminosalicylate anti-inflammatory medication used to treat inflammatory bowel disease (IBD). Metabolic bone disease Disorders of bone strength, usually caused by abnormalities of minerals, vitamin D, bone mass, or bone structure. Metabolic syndrome A group of health risks, including large waist size, high levels of triglycerides, low levels of HDL, high blood pressure, and high blood glucose levels, that increase the chance of developing heart disease, stroke, and diabetes. Metastasis A stage of cancer in which cancer cells have broken away from the primary tumor and spread to other organs in the body through the bloodstream or the lymphatic system. Methylcellulose A medication used as a bulk laxative to treat constipation. Metronidazole An antibiotic used to treat anaerobic bacterial infections. Microbiome (gut flora) Bacteria in the digestive system that help break down food into nutrients for the body to use. Migraine A recurrent throbbing headache that typically affects one side of the head and is often accompanied by nausea and disturbed vision. Mixed irritable bowel syndrome (IBS-M) Irritable bowel syndrome in which bowel habit is characterized equally by frequent constipation and frequent diarrhea. Monoclonal antibodies Laboratory-produced antibodies that are made by identical immune cells that are all clones of a unique parent cell. Monoclonal antibody therapy A type of targeted therapy that uses laboratory-produced antibodies to identify and attack cancer cells. Monosodium glutamate (MSG) A flavor enhancer commonly added to Chinese food, canned vegetables, soups, and processed meats. Motility The ability of the digestive system to move contents through the digestive tract. Mucosa A thin membrane that lines the inside of the digestive tract and other internal organs. Mumps A contagious and infectious viral disease causing swelling of the parotid salivary glands in the face. N-Z Return to top Narcotics (opiates) Medications, including oxycodone, hydrocodone, codeine, morphine, fentanyl, and others, used to relieve severe pain. Nasogastric feeding The use of a tube that is passed through the nose and down through the esophagus into the stomach for feeding. Nausea An uneasy or unsettled feeling in the stomach together with an urge to vomit, or throw up. Neoadjuvant therapy Chemotherapy, radiation therapy, or chemoradiation therapy given before surgery to shrink the tumor. Neuroendocrine cells Cells in the pancreas that produce hormones, such as insulin and glucagon. Neurotransmitter A chemical substance that acts as a messenger between nerve cells in the brain. Nitrates Medications used to treat and prevent angina (chest pain). Nitrites An additive in some foods used for coloring, antimicrobial, and flavoring effects. Nonalcoholic fatty liver disease (NAFLD) A condition in which there is an accumulation of fat in the liver of a person who drinks little or no alcohol. Nonalcoholic steatohepatitis (NASH) A serious type of nonalcoholic fatty liver disease in which inflammation and damage are caused by fat buildup in the liver. Nonsteroidal anti-inflammatory drugs (NSAIDs) Medications that reduce pain, fever, and inflammation. Norovirus A group of viruses that are a common cause of food poisoning and acute gastroenteritis. Obesity A condition in which a person has too much body fat, as measured by body mass index (BMI). A BMI 30.0 or above is considered obese. Obstruction (bowel obstruction; intestinal obstruction) A blockage of the small intestine or the large intestine that prevents the normal movement of the products of digestion. Opiates Medications, including oxycodone, hydrocodone, codeine, morphine, fentanyl, and others, used to relieve severe pain. Oral contraceptives A birth control pill taken by mouth. Osmotic agents A type of diuretic that inhibits reabsorption of water and sodium. Osteomyelitis Inflammation of bone or bone marrow. Osteopenia A condition in which there is reduced bone mass. Osteoporosis A condition in which the bones become porous and brittle, and break easily. Ovarian cyst A collection of fluid surrounded by a thin wall within the ovaries. Overweight A condition in which a person's body weight is higher than what is considered healthy, as measured by body mass index (BMI). A BMI between 25.0 and 29.9 is considered overweight. Palliative surgery Surgery done to relieve symptoms and improve quality of life, but is not curative. Pancreas A small organ in the digestive system, responsible for secreting digestive enzymes, insulin, and glucagon. Pancreatic cancer A growth of malignant cells in the tissues of the pancreas. Pancreatic duct A passageway that connects the pancreas to the common bile duct. Pancreatic enzymes Digestive enzymes produced by the pancreas. Pancreatic rest (aberrant pancreas; heterotopic pancreas; ectopic pancreas) A type of submucosal nodule in which pancreatic tissue develops under the lining, or mucosa, of another organ, such as the stomach or small intestine. Pancreatitis Inflammation of the pancreas. Panic attack A sudden episode of intense fear that triggers severe physical reactions when there is no real danger or apparent cause. Panic disorder An anxiety disorder characterized by recurring panic attacks. Parasite An organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense. Parkinson's disease A progressive disease of the nervous system marked by tremor, muscular rigidity, and slow, imprecise movement. Partial (subtotal) colectomy A surgical procedure involving the removal of part of the large intestine. Partial hepatectomy A surgical procedure in which a part of the liver is removed. Pedunculated polyp A polyp that grows on a stalk, resembling a mushroom or cauliflower. Pelvic dysfunction Abnormal function of one or more pelvic organs or muscles. Pelvic dyssynergy An inability to coordinate the pelvic and anal muscles involved in defecation. Pelvic exenteration A radical surgical treatment in which all organs are removed from a person's pelvic cavity. Pelvic organ prolapse A condition in which one or more pelvic organs slips downward. Penicillin An antibiotic or group of antibiotics used to treat some bacterial infections. Peptic ulcer A sore on the lining of the stomach or first part of the small intestine, called the duodenum. Percutaneous transhepatic biliary drainage A procedure done to drain bile when there is a blockage and endoscopic stent placement is not possible. Percutaneous transhepatic cholangiography (PTC) A procedure in which a thin needle is inserted through the skin and into the liver, and dye is injected to make the liver and bile ducts more visible on x-ray. Perforation A tear in the lining of an organ. Perihilar bile duct cancer A growth of malignant cells in the tissues of the hilum region of the biliary tree. Perineum The area between the anus and the scrotum or vulva. Peristalsis The movement of a layer of muscle in the walls of digestive organs that moves food through the digestive tract. This movement resembles an ocean wave. Peritonitis Inflammation of the peritoneum, a silk-like membrane that lines the inner abdominal wall and covers the organs within the abdomen. Pernicious anemia A type of vitamin B12 deficiency anemia, a condition in which the body does not make enough healthy red blood cells, due to a lack of intrinsic factor. Phosphate preparation An alternative bowel preparation that uses a phosphate solution or phosphate pills to cleanse the bowel before a colonoscopy. Pigment stones Dark-colored gallstones made primarily of bilirubin. Platelets Small colorless disk-shaped cell fragments without a nucleus, found in large numbers in blood and involved in clotting. Pleurisy Chest pain caused by inflammation of the linings around the lung (the pleura). Pneumococcal disease An infection caused by Streptococcus pneumoniae bacteria, which can result in many types of illnesses, including ear infections and meningitis. Pneumococcal polysaccharide vaccine (PPSV) A vaccine that protects against multiple types of pneumococcal bacteria. Pneumonia Lung inflammation caused by bacterial or viral infection, in which the air sacs fill with pus and may become solid. Polyethylene glycol A solution used to cleanse the bowels in preparation for a colonoscopy. Polyp A small growth on a surface inside the body. Polypectomy Removal of a polyp, either endoscopically or surgically. Portal hypertension High blood pressure in the portal vein, which carries blood from the stomach, intestines, spleen, gallbladder, and pancreas to the liver. Portal vein The main blood vessel carrying blood from the stomach, intestines, spleen, gallbladder, and pancreas to the liver. Post-traumatic stress disorder (PTSD) A mental health condition characterized by negative mood, intrusive memories, avoidant behavior, and hyper-arousal related to a traumatic event. Primary biliary cirrhosis (primary biliary cholangitis) (PBC) An autoimmune disease of the liver that results from a slow, progressive destruction of the small bile ducts in the liver. Primary sclerosing cholangitis (PSC) A condition in which inflammation of the bile ducts leads to scar formation and narrowing of the ducts over time. Probiotics Live bacteria and yeasts that are good for the digestive system. Proctocolectomy A surgical procedure involving the removal of the rectum and all or part of the colon. Prokinetics Medications that help the stomach empty more quickly. Prostaglandin A chemical substance in the body that participates in a wide range of functions, such as contraction and relaxation of smooth muscle, the dilation and constriction of blood vessels, control of blood pressure, and modulation of inflammation. Protectants Medications that coat ulcers and protect them against acid and enzymes so that healing can occur. Proton pump inhibitors (PPIs) Medications that lower the amount of acid the stomach makes. Pseudocyst A fluid-filled cavity resembling a cyst but lacking a wall or lining. Psoriasis A common skin condition that speeds up the life cycle of skin cells, causing cells to build up rapidly on the surface of the skin, which form scales and red patches that are itchy and sometimes painful. Psyllium A leafy-stemmed Eurasian plantain, the seeds of which are used as a laxative and as a bulking agent. Pulmonary embolism A blockage in one of the pulmonary arteries in the lungs, often cause by blood clots. Pyloric sphincter A ring of muscle that allows food to leave the stomach and enter the small intestine. Quadruple therapy A regimen of four medications used to treat peptic ulcers caused by H. pylori. Radiation therapy A medical treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. Radio frequency A medical treatment that uses an electrical current produced by a radio wave to heat the area of concern. Radio frequency ablation A procedure that uses a special probe with tiny electrodes to kill cancer cells. Radiologic guided drainage A procedure that uses imaging guidance to place a needle or catheter through the skin into an abscess to remove or drain the infected fluid. Radiologic test A variety of imaging techniques, such as x-ray, ultrasound, computed tomography, nuclear imaging, and magnetic resonance imaging used to diagnose and/or treat diseases. Rectal compliance The ability of the rectum to relax and store stool. Rectal intussusception Also called incomplete prolapse, a condition in which part of the rectum slips downward. Rectal prolapse A condition in which all or part of the rectum slips downward through the anus. Rectal sensation The ability to sense the presence of stool in the rectum. Rectocele A condition in women in which the front of the rectum protrudes into the back of the vagina. Rectum A section of the large intestine, responsible for storing stool until the muscles contract to push the stool out of the body through the anus. Red blood cells Blood cells that carry oxygen throughout the body. Regional chemotherapy A medical treatment, placed directly into the affected organ, that targets cancer cells in a specific area, or region, of the body. Resection A surgical removal of all or part of a damaged organ or structure, particularly the removal of a tumor. Retching An attempt to vomit. Rheumatoid arthritis A chronic, progressive disease causing inflammation in the joints and resulting in painful deformity and immobility. Rifaximin An antibiotic medication used to treat diarrhea, irritable bowel syndrome, and hepatic encephalopathy. Rotavirus A group of viruses that are a leading cause of severe diarrhea and dehydration in young children. Rubella A contagious viral disease, with symptoms like mild measles. Rugae Ridges of muscle lining the stomach that churn and mix food with stomach acid to help digestion. Saliva Watery liquid secreted into the mouth by glands, providing lubrication for chewing and swallowing, and aiding digestion. Salmonella A bacterium that occurs mainly in the intestine, which causes food poisoning. Schatzki ring A narrowing of the lower esophagus, caused by a ring of mucosal tissue or muscular tissue, that can cause difficulty swallowing. Scleroderma A chronic connective tissue disease characterized by a hardening of the skin. Sedatives Medications that slow brain activity, ease agitation, and permit sleep. Sequential therapy A regimen of several medications taken in a particular sequence to treat peptic ulcers caused by H. pylori. Sessile polyp A polyp that doesn't have a stalk, appearing flat or as a small bump. Shigella A bacterium that is an intestinal pathogen of humans, some kinds of which cause dysentery. Shigellosis A gastrointestinal infection caused by shigella bacteria. Shingles A disease caused by the varicella-zoster virus and characterized by skin eruptions and painful inflammation of the nerve ganglia. Shock A critical condition, common after serious injury, that is brought on by a sudden drop in blood flow through the body. Sigmoid colon The curving, lower part of the large intestine, between the descending colon and the rectum. Silent gallstones Gallstones that do not cause any symptoms. Simple cyst A fluid-filled sac that forms under the lining, or mucosa, of the GI tract. Simple fatty liver Nonalcoholic fatty liver disease that does not cause any problems or have any symptoms. Sinus infection An inflammation of the soft tissues that line the sinuses. Skullcap A hardy perennial herb of the mint family. Small bowel resection A surgical procedure involving the removal of part of the small intestine. Small intestine (small bowel) A long, tightly packed organ in the digestive tract, responsible for digesting carbohydrates and protein from food and drink. Somatoform disorder A group of psychological disorders in which a person experiences physical symptoms that are inconsistent with or cannot be fully explained by any underlying general medical or neurologic condition. Sorbitol intolerance An inability to digest sorbitol, which is a sweet-tasting crystalline compound found in some fruit. Sphincter A ring of muscle that opens and closes to allow passage between organs. Sphinctorectomy An endoscopic procedure in which a cut is made in the muscle that surrounds the pancreatic duct or bile ducts to enlarge the opening. Spider angiomas A type of swollen blood vessels found slightly beneath the skin surface, often containing a central red spot and reddish extensions which radiate outwards like a spider's web. Spleen An abdominal organ involved in the production and removal of blood cells and forming part of the immune system. Splenomegaly Abnormal enlargement of the spleen. Spontaneous bacterial peritonitis An acute bacterial infection of ascitic fluid. Sporadic GIST A condition in which a person has a single gastrointestinal stromal tumor (GIST). Squamous cell carcinoma A type of cancer that forms in the thin, flat cells (squamous cells) that make up the outermost layer of the skin and line the surface of the esophagus. Staphylococcus aureus A gram-positive bacterium that is found on the skin and in the nasal passages of about a quarter of humans, which can cause serious infection of the skin, soft tissues, GI tract, and lungs. Starches A type of carbohydrate, also referred to as a complex carbohydrate. Statins A group of medications that act to reduce levels of fats, including triglycerides and cholesterol, in blood. Steatosis Infiltration of liver cells with fat. Stenosis The abnormal narrowing of a body channel. Stent A short, narrow metal or plastic tube, often in the form of a mesh, that is placed inside a blood vessel, canal, or duct to relieve narrowing or obstruction. Stimulant laxative Fast-acting laxative medications that induce bowel movements by increasing the contraction of muscles in the intestines. Stoma A surgically created opening on the outside of the body leading to the gut or trachea. Stomach An organ in the digestive tract, responsible for digesting protein from food and drink. Stomach acid Digestive juice secreted by the stomach. Stomach cancer (gastric cancer) A growth of malignant cells in the tissues of the stomach. Stool Solid matter formed in the large intestine as water and salt are absorbed from waste. Stricture A narrowing of a passageway, such as the esophagus or a bile duct. Stroke An interruption of the blood flow to the brain, which leads to permanent damage and/or persistent symptoms. Stupor A state of near-unconsciousness or insensibility. Submucosal nodule (submucosal lesion; submucosal tumor) An abnormal growth that originates under the lining (mucosa) of gastrointestinal organs. Subtotal (partial) colectomy A surgical procedure involving the removal of part of the large intestine. Subtotal gastrectomy A surgical treatment that involves the removal of part of the stomach and parts of surrounding tissues and organs. Suppository A solid medical preparation in a roughly conical or cylindrical shape, designed to be inserted into the rectum or vagina to dissolve. Systemic chemotherapy A medical treatment, taken by mouth or injected into a vein or muscle, that targets cancer cells throughout the body. Systemic lupus erythematosus An autoimmune disease that can affect the skin, joints, kidneys, brain, and other organs. Tachyphylaxis An acute, sudden decrease in response to a drug after its administration; a rapid and short-term onset of drug tolerance. Tap water enema An injection of plain water into the rectum in order to stimulate a bowel movement. Targeted therapy A medical treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Tarry stool Stool that is either dark red or black in color. Tdap vaccine A booster immunization given to protect against diphtheria, tetanus, and whooping cough. Temporomandibular joint disorder Pain and dysfunction of the muscles that move the jaw and the joints which connect the jaw to the skull. Tetanus A bacterial disease marked by rigidity and spasms of the voluntary muscles. Tetracycline A family of broad-spectrum antibiotic medications used to treat a variety of infections. Thorotrast A suspension containing particles of a radioactive compound that was used as a radiocontrast agent in medical radiography in the 1930s and 1940s. Tinidazole An antibiotic used to treat certain types of vaginal infections and parasite infections. Total gastrectomy A surgical procedure involving the removal of the entire stomach, parts of the esophagus, small intestine, and other tissues and organs nearby. The esophagus is connected to the small intestine to allow eating and swallowing. Total pancreatectomy A surgical procedure involving the removal of the entire pancreas. Toxic megacolon A rare, life-threatening dilation of the large intestine, usually a complication of inflammatory bowel disease (IBD). Toxoplasma gondii (T. gondii) A parasite that can only reproduce in cats and causes infections when its cysts are ingested. Transverse colon The third part of the large intestine, between the ascending colon and the descending colon, that travels across the abdomen. Triglyceride A kind of lipid or fat, which, in high concentrations in the blood, indicate an elevated risk of stroke. Triple therapy A regimen of three medications used to treat peptic ulcers caused by H. pylori. Tuberculosis An infectious bacterial disease characterized by the growth of nodules (tubercles) in the tissues, especially the lungs. Tumor An abnormal growth of tissue that can be either benign (noncancerous) or malignant (cancerous). Tumor necrosis factor (TNF) A protein capable of inducing necrosis (death) of tumor cells. Type 2 diabetes A type of diabetes in which the insulin produced is either not enough or doesn't work properly in the body. Tyrosine kinase inhibitors (TKIs) A type of targeted therapy that blocks the action of enzymes related to cell signaling, growth, and division. Ulcerative colitis An inflammatory bowel disease (IBD) that causes long-lasting inflammation and ulcers in the digestive tract. Ultrasound A noninvasive procedure that uses high-frequency sound waves to create images of internal organs and soft tissues. Unsubtyped irritable bowel syndrome (IBS-U) Irritable bowel syndrome in which bowel habit is not frequently characterized by constipation or diarrhea. Upper esophageal sphincter (UES) A ring of muscle at the top of the esophagus that controls swallowing and keeps food and drink from entering the windpipe. Upper gastrointestinal (GI) endoscopy A procedure that allows a provider to view the lining of the upper GI tract, including the esophagus, stomach, and the first part of the small intestine, called the duodenum, using an endoscope. Upper gastrointestinal (GI) series (barium swallow) A procedure that uses x-rays and a chalky liquid called barium to view the upper GI tract, including the esophagus, stomach, and first part of the small intestine (duodenum). Urea nitrogen Waste product from the breakdown of protein in the body, which is normally filtered by the kidneys and leaves the body through urine. Urinary tract infection (UTI) An infection of any part or parts of the urinary system, which includes the urethra, the bladder, the ureters, and the kidneys. Ursodiol A medication that is used to dissolve gallstones in people who can't have surgery to remove them. Uterine fibroids Benign growths of the uterus from a mix of muscle and fibrous tissues. Varices Abnormally dilated or enlarged blood vessels. Villi Small finger-like projections that line the inside of the small intestine to increase the surface area for absorbing nutrients from food. Vinyl chloride A colorless toxic gas used in manufacturing plastics. Virtual colonoscopy (CT colonography) A procedure that uses a combination of x-rays and computer technology to create multiple high-resolution cross-sectional images of the colon and rectum. Virus A microorganism that is smaller than bacteria that cannot grow or reproduce apart from the living cells of other organisms. Vitamin B12 A vitamin important for the normal function of red blood cells and the health of nerve tissues. Vitamin B12 deficiency anemia A condition in which the body does not have enough healthy red blood cells due to a lack of vitamin B12. Whipple procedure A surgical procedure in which the head of the pancreas, the gallbladder, part of the stomach, part of the small intestine, and the bile duct are removed. White blood cells Nearly colorless cells of the immune system that circulate in the blood and lymph and help fight infections. Whooping cough A contagious bacterial disease chiefly affecting children, characterized by convulsive coughs followed by a whoop. Wilson's disease A genetic disorder in which copper builds up in the body. X-ray A procedure that uses low-level radiation that passes through the body to produce a two-dimensional picture called a radiograph. Yohimbe A tropical West African tree of the bedstraw family. Zoster vaccine A vaccine that protects against shingles.