Gastroenterology (from the Greek gastḗr- "belly", -énteron "intestine", and -logía "study of") is the branch of

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

focused on the

digestive system The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller compone ...

and its disorders. The digestive system consists of the

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...

, sometimes referred to as the ''GI tract,'' which includes the

esophagus The esophagus (American English), oesophagus (British English), or œsophagus (Œ, archaic spelling) (American and British English spelling differences#ae and oe, see spelling difference) all ; : ((o)e)(œ)sophagi or ((o)e)(œ)sophaguses), c ...

stomach The stomach is a muscular, hollow organ in the upper gastrointestinal tract of Human, humans and many other animals, including several invertebrates. The Ancient Greek name for the stomach is ''gaster'' which is used as ''gastric'' in medical t ...

small intestine The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...

and

large intestine The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the Digestion, digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces befor ...

as well as the

accessory organs of digestion The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller compone ...

which include the

pancreas The pancreas (plural pancreases, or pancreata) is an Organ (anatomy), organ of the Digestion, digestive system and endocrine system of vertebrates. In humans, it is located in the abdominal cavity, abdomen behind the stomach and functions as a ...

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow Organ (anatomy), organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath t ...

, and

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

. The digestive system functions to move material through the GI tract via

peristalsis Peristalsis ( , ) is a type of intestinal motility, characterized by symmetry in biology#Radial symmetry, radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an wikt:anterograde, anterograde dir ...

, break down that material via

digestion Digestion is the breakdown of large insoluble food compounds into small water-soluble components so that they can be absorbed into the blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into th ...

, absorb nutrients for use throughout the body, and remove waste from the body via

defecation Defecation (or defaecation) follows digestion and is the necessary biological process by which organisms eliminate a solid, semisolid, or liquid metabolic waste, waste material known as feces (or faeces) from the digestive tract via the anus o ...

. Physicians who specialize in the medical specialty of gastroenterology are called gastroenterologists or sometimes ''GI doctors''. Some of the most common conditions managed by gastroenterologists include

gastroesophageal reflux disease Gastroesophageal reflux disease (GERD) or gastro-oesophageal reflux disease (GORD) is a chronic upper gastrointestinal disease in which stomach content persistently and regularly flows up into the esophagus, resulting in symptoms and/or ...

gastrointestinal bleeding Gastrointestinal bleeding (GI bleed), also called gastrointestinal hemorrhage (GIB), is all forms of bleeding in the gastrointestinal tract, from the mouth to the rectum. When there is significant blood loss over a short time, symptoms may includ ...

irritable bowel syndrome Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by a group of symptoms that commonly include abdominal pain, abdominal bloating, and changes in the consistency of bowel movements. These symptoms may ...

, inflammatory bowel disease (IBD) which includes

Crohn's disease Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea, fever, abdominal distension, and weight loss. Complications outside of the ...

and

ulcerative colitis Ulcerative colitis (UC) is one of the two types of inflammatory bowel disease (IBD), with the other type being Crohn's disease. It is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary sympto ...

peptic ulcer disease Peptic ulcer disease is when the inner part of the stomach's gastric mucosa (lining of the stomach), the first part of the small intestine, or sometimes the lower esophagus, gets damaged. An ulcer in the stomach is called a gastric ulcer, while ...

, gallbladder and biliary tract disease,

hepatitis Hepatitis is inflammation of the liver parenchyma, liver tissue. Some people or animals with hepatitis have no symptoms, whereas others develop yellow discoloration of the skin and whites of the eyes (jaundice), Anorexia (symptom), poor appetite ...

pancreatitis Pancreatitis is a condition characterized by inflammation of the pancreas. The pancreas is a large organ behind the stomach that produces digestive enzymes and a number of hormone A hormone (from the Ancient Greek, Greek participle , "se ...

colitis Colitis is swelling or inflammation Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and ...

, colon polyps and cancer, nutritional problems, and many more.

History

Citing from

Egyptian ''Egyptian'' describes something of, from, or related to Egypt. Egyptian or Egyptians may refer to: Nations and ethnic groups * Egyptians, a national group in North Africa ** Egyptian culture, a complex and stable culture with thousands of year ...

papyri Papyrus ( ) is a material similar to thick paper that was used in ancient times as a writing surface. It was made from the pith of the papyrus plant, ''Cyperus papyrus'', a wetland sedge. ''Papyrus'' (plural: ''papyri'' or ''papyruses'') can ...

, John F. Nunn identified significant knowledge of gastrointestinal diseases among practicing physicians during the periods of the

pharaoh Pharaoh (, ; Egyptian language, Egyptian: ''wikt:pr ꜥꜣ, pr ꜥꜣ''; Meroitic language, Meroitic: 𐦲𐦤𐦧, ; Biblical Hebrew: ''Parʿō'') was the title of the monarch of ancient Egypt from the First Dynasty of Egypt, First Dynasty ( ...

s. Irynakhty, of the tenth dynasty, 2125 B.C., was a

court physician A court is an institution, often a government entity, with the authority to adjudicate legal disputes between parties and administer justice in civil, criminal, and administrative matters in accordance with the rule of law. Courts genera ...

specializing in gastroenterology, sleeping, and

proctology Colorectal surgery is a field in medicine dealing with disorders of the rectum, anus, and colon. The field is also known as proctology, but this term is now used infrequently within medicine and is most often employed to identify practices relati ...

. Among

ancient Greeks Ancient Greece () was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity (), that comprised a loose collection of culturally and linguistically re ...

Hippocrates Hippocrates of Kos (; ; ), also known as Hippocrates II, was a Greek physician and philosopher of the Classical Greece, classical period who is considered one of the most outstanding figures in the history of medicine. He is traditionally referr ...

attributed

concoction Concoction is the process of preparing a medicine, food or other substance out of many ingredients, and also the result of such a process. Historically, the word referred to digestion, as conceived by Aristotle who theorized that this was the res ...

Galen Aelius Galenus or Claudius Galenus (; September 129 – AD), often Anglicization, anglicized as Galen () or Galen of Pergamon, was a Ancient Rome, Roman and Greeks, Greek physician, surgeon, and Philosophy, philosopher. Considered to be one o ...

's concept of the

having four ''faculties'' was widely accepted up to modernity in the seventeenth century.

18th century

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, a Romance ethnic group related to or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance languag ...

Lazzaro Spallanzani Lazzaro Spallanzani (; 12 January 1729 – 11 February 1799) was an Italian Catholic priest (for which he was nicknamed Abbé Spallanzani), biologist and physiologist who made important contributions to the experimental study of bodily function ...

(1729–99) was among early

physician A physician, medical practitioner (British English), medical doctor, or simply doctor is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through the Medical education, study, Med ...

s to disregard Galen's theories, and in 1780 he gave experimental proof on the action of

gastric juice Gastric glands are glands in the lining of the stomach that play an essential role in the digestion, process of digestion. Their secretions make up the gastric acid, digestive gastric juice. The gastric glands open into gastric pits in the gastri ...

on foodstuffs. * In 1767,

German German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also Ge ...

Johann von Zimmermann wrote an important work on

dysentery Dysentery ( , ), historically known as the bloody flux, is a type of gastroenteritis that results in bloody diarrhea. Other symptoms may include fever, abdominal pain, and a feeling of incomplete defecation. Complications may include dehyd ...

. * In 1777,

Maximilian Stoll Maximilian Stoll (October 12, 1742 – May 25, 1787) was an Austrian physician who was a native of Erzingen, Baden-Württemberg. Stoll originally trained as a theologian, with his interests later turning to medicine, and in 1776 attained a profe ...

Vienna Vienna ( ; ; ) is the capital city, capital, List of largest cities in Austria, most populous city, and one of Federal states of Austria, nine federal states of Austria. It is Austria's primate city, with just over two million inhabitants. ...

described cancer of the gallbladder.

19th century

* In 1805,

Philipp Bozzini Philipp Bozzini (May 25, 1773 – April 4, 1809) was born in Mainz, Germany. On June 12, 1797, he was awarded the degree of doctor of medicine. From 1804 onwards, Bozzini devoted himself virtually completely to develop his instrument, Lichtleiter ...

made the first attempt to observe inside the living human body using a tube he named ''Lichtleiter'' (light-guiding instrument) to examine the

urinary tract The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressu ...

, the

rectum The rectum (: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. Before expulsion through the anus or cloaca, the rectum stores the feces temporarily. The adult ...

, and the

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

. This is the earliest description of

endoscopy An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are insert ...

. *

Charles Emile Troisier Charles is a masculine given name predominantly found in English and French speaking countries. It is from the French form ''Charles'' of the Proto-Germanic name (in runic alphabet) or ''*karilaz'' (in Latin alphabet), whose meaning was ...

described enlargement of

lymph node A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that includ ...

s in abdominal cancer. * In 1823,

William Prout William Prout Fellow of the Royal Society, FRS (; 15 January 1785 – 9 April 1850) was an English chemist, physician, and natural theologian. He is remembered today mainly for what is called Prout's hypothesis. Biography Prout was born in H ...

discovered that

juices contain

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

. * In 1833,

William Beaumont William Beaumont (November 21, 1785 – April 25, 1853) was a surgeon in the U.S. Army who became known as the "Father of Gastric Physiology" for his research on human digestion on Alexis St. Martin.Alexis St. Martin. * In 1868,

Adolf Kussmaul Adolf Kussmaul (; 22 February 1822 – 28 May 1902) was a German physician and a leading clinician of his time. Biography Adolf Kussmaul was born as the son and grandson of physicians in Graben near Karlsruhe and studied at Heidelberg. He ente ...

, a well-known German physician, developed the gastroscope. He perfected the technique on a

sword swallower Sword swallowing is a skill in which the performer passes a sword through the mouth and down the esophagus to the stomach. This feat is not swallowing in the traditional sense. The natural processes that constitute swallowing do not take place, bu ...

. * In 1871, at the society of physicians in Vienna, Carl Stoerk demonstrated an esophagoscope made of two telescopic metal tubes, initially devised by Waldenburg in 1870. * In 1876, Karl Wilhelm von Kupffer described the properties of some liver cells now called

Kupffer cell Kupffer cells, also known as stellate macrophages and Kupffer–Browicz cells, are specialized cells localized in the liver within the lumen of the liver sinusoids and are adhesive to their endothelial cells which make up the blood vessel walls. K ...

s. * In 1883,

Hugo Kronecker Karl Hugo Kronecker (27 January 1839 – 6 June 1914) was a German physiologist from Liegnitz, Prussian Silesia. He was the brother of Leopold Kronecker. He studied medicine in Berlin, Heidelberg and Pisa, and received the M.D. degree in Be ...

and

Samuel James Meltzer Samuel James Meltzer (March 22, 1851 – November 7, 1920) was an American Physiology, physiologist. Samuel Meltzer was educated at the Realgymnasium in Königsberg and then studied philosophy and medicine at the Humboldt University of Berlin, U ...

studied oesophageal manometry in humans.

20th century

* In 1915, Jesse McClendon tested

acidity An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the ...

of human stomach ''

in situ is a Latin phrase meaning 'in place' or 'on site', derived from ' ('in') and ' ( ablative of ''situs'', ). The term typically refers to the examination or occurrence of a process within its original context, without relocation. The term is use ...

''. * In 1921–22,

Walter Alvarez Walter Alvarez (born October 3, 1940) is a professor in the Earth and Planetary Science department at the University of California, Berkeley. He and his father, Nobel Prize–winning physicist Luis Alvarez, developed the theory that dinosaurs w ...

did the first electrogastrography research. * Rudolf Schindler described many important diseases involving the human digestive system during

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

in his illustrated textbook and is portrayed by some as the "father of gastroscopy". He and Georg Wolf developed a semiflexible gastroscope in 1932. * In 1932,

Burrill Bernard Crohn Burrill Bernard Crohn (June 13, 1884 – July 29, 1983) was an American gastroenterologist who made the first major advance to identify Crohn's disease, which bears his name. Although the description of Crohn's disease is his most famous accompli ...

described

. * In 1957,

Basil Hirschowitz Basil Isaac Hirschowitz (29 May 1925 – 19 January 2013) was an academic gastroenterologist from the University of Alabama at Birmingham (UAB) best known in the field for having invented an improved optical fiber which allowed the creation o ...

introduced the first prototype of a fibreoptic gastroscope.

21st century

* In 2005,

Barry Marshall Barry James Marshall (born 30 September 1951) is an Australian physician, Nobel Laureate in Physiology or Medicine, Professor of Clinical Microbiology and Co-Director of the Marshall Centre at the University of Western Australia. Marshall and ...

and

Robin Warren John Robin Warren (11 June 1937 – 23 July 2024) was an Australian pathologist, Nobel laureate, and researcher who is credited with the 1979 re-discovery of the bacterium '' Helicobacter pylori'', together with Barry Marshall. The duo pr ...

of Australia were awarded the

Nobel Prize in Physiology or Medicine The Nobel Prize in Physiology or Medicine () is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, acco ...

for their discovery of ''

Helicobacter pylori ''Helicobacter pylori'', previously known as ''Campylobacter pylori'', is a gram-negative, Flagellum#bacterial, flagellated, Bacterial cellular morphologies#Helical, helical bacterium. Mutants can have a rod or curved rod shape that exhibits l ...

'' (1982/1983) and its role in

. James Leavitt assisted in their research, but the Nobel Prize is not awarded posthumously so he was not included in the award.

Disease classification

1. International Classification of Disease (

ICD The International Classification of Diseases (ICD) is a globally used medical classification that is used in epidemiology, health management and clinical diagnostics, diagnosis. The ICD is maintained by the World Health Organization (WHO), which ...

2007)/WHO classification: * Chapter XI, Diseases of the digestive system,(K00-K93) 2.

MeSH Medical Subject Headings (MeSH) is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences. It serves as a thesaurus of index terms that facilitates searching. Created and updated by th ...

subject Heading: * Gastroenterology (G02.403.776.409.405) * Gastroenterological diseases(C06.405) 3.

National Library of Medicine The United States National Library of Medicine (NLM), operated by the United States federal government, is the world's largest medical library. Located in Bethesda, Maryland, the NLM is an institute within the National Institutes of Health. I ...

Catalogue (NLM classification 2006): * Digestive system(W1)

Procedures

Colonoscopy

A procedure using a long thin tube with a camera that is passed through the

anus In mammals, invertebrates and most fish, the anus (: anuses or ani; from Latin, 'ring' or 'circle') is the external body orifice at the ''exit'' end of the digestive tract (bowel), i.e. the opposite end from the mouth. Its function is to facil ...

to visualize the

and the entire length of the colon. The procedure is performed either to look for colon polyps and/or

colon cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel ...

in somebody without symptoms, referred to as screening, or to further evaluate symptoms including

rectal bleeding Rectal bleeding refers to bleeding in the rectum, thus a form of lower gastrointestinal bleeding. There are many causes of rectal hemorrhage, including inflamed hemorrhoids (which are dilated vessels in the perianal fat pads), rectal varices, pr ...

, dark tarry stools, change in bowel habits or stool consistency (diarrhea, pencil-thin stool), abdominal pain, and unexplained weight loss. Before the procedure, the physician might ask the patient to stop taking certain medications including blood thinners, aspirin, diabetes medications, or

nonsteroidal anti-inflammatory drug Non-steroidal anti-inflammatory drugs (NSAID) are members of a Indication (medicine), therapeutic drug class which Analgesic, reduces pain, Anti-inflammatory, decreases inflammation, Antipyretic, decreases fever, and Antithrombotic, prevents bl ...

s. A bowel prep is usually taken the night before and into the morning of the procedure which consists of an

enema An enema, also known as a clyster, is the rectal administration of a fluid by injection into the Large intestine, lower bowel via the anus.Cullingworth, ''A Manual of Nursing, Medical and Surgical'':155 The word ''enema'' can also refer to the ...

laxative Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...

s, either pills or powder dissolved in liquid, that will cause diarrhea. The procedure might need to be stopped and rescheduled if there is stool remaining in the colon due to an incomplete bowel prep because the physician can not adequately visualize the colon. During the procedure, the patient is sedated and the scope is used to examine the entire length of the colon looking for polyps, bleeding, or abnormal tissue. A

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, an interventional radiologist, or an interventional cardiology, interventional cardiologist. The process involves the extraction of sampling (medicine), sample ...

or polyp removal can then be performed and the tissue sent to the lab for evaluation. The procedure usually takes thirty minutes to an hour followed by a one to two hour observation period. Complications include bloating, cramping, a reaction to anesthesia, bleeding, and a hole through the wall of the colon that may require repeat colonoscopy or surgery. Signs of a serious complication requiring urgent or emergent medical attention include severe pain in the abdomen, fever, bleeding that does not improve, dizziness, and weakness.

Sigmoidoscopy

A procedure similar to a colonoscopy using a long thin tube with a camera (scope) passed through the

but only intended to visualize the

and the last part of the colon closest to the rectum. All aspects of the procedure are the same as for a colonoscopy with the exception that this procedure only lasts ten to twenty minutes and is done without sedation. This usually allows for the patient to return to normal activities immediately after the procedure is finished.

Esophagogastroduodenoscopy (EGD)

A procedure using a long thin tube with a camera that is passed through the mouth to view the

("esophago-"),

("gastro-"), and the

duodenum The duodenum is the first section of the small intestine in most vertebrates, including mammals, reptiles, and birds. In mammals, it may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest p ...

("duodeno-"). It is also referred to as upper endoscopy or just endoscopy. The procedure is performed for further evaluation of symptoms including persistent

heartburn Heartburn is a burning sensation felt behind the breastbone. It is a symptom that is commonly linked to acid reflux and is often triggered by food, particularly fatty, sugary, spicy, chocolate, citrus, onion-based and tomato-based products. Ly ...

indigestion Indigestion, also known as dyspepsia or upset stomach, is a condition of impaired digestion. Symptoms may include upper abdominal fullness, heartburn, nausea, belching, or upper abdominal pain. People may also experience feeling full earlier ...

vomiting blood Hematemesis is the vomiting of blood. It can be confused with hemoptysis (coughing up blood) or Nosebleed, epistaxis (nosebleed), which are more common. The source is generally the upper gastrointestinal tract, typically above the suspensory mus ...

, dark tarry stools, persistent nausea and vomiting, pain,

difficulty swallowing Dysphagia is difficulty in swallowing. Although classified under " symptoms and signs" in ICD-10, in some contexts it is classified as a condition in its own right. It may be a sensation that suggests difficulty in the passage of solids or li ...

, painful swallowing, and unexplained weight loss. It is also performed for further testing following a lab test that shows low hemoglobin levels without a known cause or an abnormal

barium swallow An upper gastrointestinal series, also called a barium swallow, barium study, or barium meal, is a series of radiographs used to examine the gastrointestinal tract for abnormalities. A contrast medium, usually a radiocontrast agent such as bariu ...

. The procedure can be used to diagnose many disorders through direct visualization or tissue biopsy including

esophageal varices Esophageal varices are extremely Vasodilation, dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendenc ...

esophageal stricture A benign esophageal stricture, or peptic stricture, is a narrowing or tightening of the esophagus that causes swallowing difficulties. Signs and symptoms Symptoms of esophageal strictures include heartburn, bitter or acid taste in the mouth, cho ...

Barrett's esophagus Barrett's esophagus is a condition in which there is an abnormal ( metaplastic) change in the mucosal cells that line the lower part of the esophagus. The cells change from stratified squamous epithelium to simple columnar epithelium, intersper ...

, cancer,

celiac disease Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine. Patients develop intolerance to gluten, which is present in foods such as wheat, rye, spel ...

gastritis Gastritis is the inflammation of the lining of the stomach. It may occur as a short episode or may be of a long duration. There may be no symptoms but, when symptoms are present, the most common is upper abdominal pain (see dyspepsia). Othe ...

, and a H. pylori infection. Intra-operative techniques can then be used for treatment of certain disorders like banding esophageal varices or dilating esophageal strictures. The patient will likely be required to not eat or drink anything starting 4 hours prior to the procedure. Sedation is usually required for patient comfort. This procedure usually lasts around thirty minutes followed by a one to two hour observation period. Side effects include

bloating Abdominal bloating (or simply bloating) is a short-term disease that affects the gastrointestinal tract. Bloating is generally characterized by an excess buildup of gas, air or fluids in the stomach. A person may have feelings of tightness, pressu ...

, nausea, and a sore throat for 1 to 2 days. Complications are rare but include reaction to the anesthesia, bleeding, and a hole through the wall of the esophagus, stomach, or small intestine which could require surgery. Signs of a serious complication requiring urgent or emergent medical attention include chest pain, problems breathing, problems swallowing, throat pain that gets worse, vomiting with blood or the appearance of " coffee-grounds", worsening abdominal pain,

bloody ''Bloody'', as an adjective or adverb, is an expletive attributive commonly used in British English, Irish English, New Zealand English and Australian English; it is also present in Canadian English, Indian English, Malaysian/Singaporean ...

or black tarry stool, and fever.

Endoscopic Retrograde Cholangiopancreatography (ERCP)

A procedure using a long thin tube with a camera passed through the mouth into the first part of the small intestine to locate, diagnose, and treat disorders related to the

bile Bile (from Latin ''bilis''), also known as gall, is a yellow-green/misty green fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is primarily composed of water, is pro ...

and

pancreatic duct The pancreatic duct or duct of Wirsung (also, the major pancreatic duct due to the existence of an accessory pancreatic duct) is a duct joining the pancreas to the common bile duct. This supplies it with pancreatic juice from the exocrine pancre ...

s. These ducts carry fluids that help with digesting food from the liver, gallbladder, and pancreas and can become narrowed or blocked as a result of

gallstone A gallstone is a stone formed within the gallbladder from precipitated bile components. The term cholelithiasis may refer to the presence of gallstones or to any disease caused by gallstones, and choledocholithiasis refers to the presence of ...

s, infection, inflammation,

pancreatic pseudocyst A pancreatic pseudocyst is a circumscribed collection of fluid rich in pancreatic enzymes, blood, and non-necrotic tissue, typically located in the lesser sac of the abdomen. Pancreatic pseudocysts are usually complications of pancreatitis, alt ...

s, and tumors of the bile ducts or pancreas. As a result, one may experience back pain, yellowing of the skin, and an abnormal lab test showing an elevated

bilirubin Bilirubin (BR) (adopted from German, originally bili—bile—plus ruber—red—from Latin) is a red-orange compound that occurs in the normcomponent of the straw-yellow color in urine. Another breakdown product, stercobilin, causes the brown ...

level which could necessitate this procedure. However, the procedure is not recommended if the patient has

acute pancreatitis Acute pancreatitis (AP) is a sudden inflammation of the pancreas. Causes include a gallstone impacted in the common bile duct or the pancreatic duct, heavy alcohol use, systemic disease, trauma, elevated calcium levels, hypertriglyceridemia (w ...

unless the level of bilirubin remains high or is increasing which could suggest the blockage is still present. The patient will likely be required to not eat or drink anything starting 8 hours prior to the procedure. After the patient is sedated, the physician will pass the scope through the mouth, esophagus, stomach, and into the duodenum to locate the

opening Opening may refer to: Types of openings * Hole * A title sequence or opening credits * Grand opening of a business or other institution * Inauguration * Keynote * Opening sentence * Opening sequence * Opening statement, a beginning statemen ...

where the ducts drain into the small intestine. The physician can then inject dye into these ducts and take X-rays which show a real time view, via

fluoroscopy Fluoroscopy (), informally referred to as "fluoro", is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a surgeon to see t ...

, allowing the physician to locate and relieve the blockage. This is done through multiple techniques including cutting the opening and creating a bigger hole for drainage, removing gallstones and other debris, dilating narrow parts of the ducts, or placing a stent which keeps the ducts open. The physician can also take a

of the ducts to evaluate for cancer, infection, or inflammation. Side effects include bloating, nausea, or a sore throat for one to two days. Complications include

, infection of the

bile ducts A bile duct is any of a number of long tube-like structures that carry bile, and is present in most vertebrates. The bile duct is separated into three main parts: the fundus (superior), the body (middle), and the neck (inferior). Bile is requ ...

, bleeding, reaction to the anesthesia, and perforation of any structures that the scope or its instruments pass but particularly the duodenum, bile duct, and pancreatic duct. Signs of a serious complication requiring urgent or emergent medical attention include bloody or black tarry stool, chest pain, fever, worsening abdominal pain, worsening throat pain, problems breathing, problems swallowing, vomit that is bloody or looks like coffee-grounds. Most of the time complications from this procedure require hospitalization for treatment.

Ultrasound and Bowel Ultrasound

Ultrasound Ultrasound is sound with frequency, frequencies greater than 20 Hertz, kilohertz. This frequency is the approximate upper audible hearing range, limit of human hearing in healthy young adults. The physical principles of acoustic waves apply ...

has become a standard tool in many medical settings. Its widespread availability, affordability, safety, and lack of radiation have established it as a common initial diagnostic method. In gastroenterology, ultrasound is highly accurate in diagnosing various conditions (e.g.,

Appendicitis Appendicitis is inflammation of the Appendix (anatomy), appendix. Symptoms commonly include right lower abdominal pain, nausea, vomiting, fever and anorexia (symptom), decreased appetite. However, approximately 40% of people do not have these t ...

Diverticulitis Diverticulitis, also called colonic diverticulitis, is a gastrointestinal disease characterized by inflammation of abnormal pouches—Diverticulum, diverticula—that can develop in the wall of the large intestine. Symptoms typically include lo ...

). Furthermore, bowel ultrasound is crucial for identifying and managing

Inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

and their complications, including the early detection of

recurrence after surgery, as highlighted in the ECCO–ESGAR guidelines. Modern ultrasound techniques like contrast-enhanced ultrasound offer real-time functional and vascular information, improving diagnostic capabilities. Additionally, operative abdominal ultrasound is increasingly important in minimally invasive interventions, including guided

biopsies A biopsy is a medical test commonly performed by a surgeon, an interventional radiologist, or an interventional cardiologist. The process involves the extraction of sample cells or tissues for examination to determine the presence or extent of ...

, drainage, and thermal ablation of liver lesions. Nevertheless, the accuracy of ultrasound is operator-dependent, and inadequate training can lead to diagnostic errors. The European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) has established guidelines to define professional standards and the minimum training needed for ultrasound examinations. These guidelines outline three levels of expertise based on anatomical knowledge, the ability to assess diseases using ultrasound, and the volume of exams performed (at least 300 per year for level 1). A recent study indicated that the majority of young Italian gastroenterologists (<40 y.o.) (58.9%) acquired their ultrasound skills during their gastroenterology training. Throughout their training, participants performed a median of 320 abdominal ultrasound examinations and 240 bowel ultrasound examinations.

Disorders

Esophagus

Gastroesophageal reflux disease (GERD)

A condition that is a result of stomach contents consistently coming back up into the esophagus causing troublesome symptoms or complications. Symptoms are considered troublesome based on how disruptive they are to a patient's daily life and well-being. This definition was standardized by the Montreal Consensus in 2006. Symptoms include a painful feeling in the middle of the chest and feeling stomach contents coming back up into the mouth. Other symptoms include chest pain, nausea,

, painful swallowing, coughing, and hoarseness. Risk factors include obesity, pregnancy, smoking,

hiatal hernia A hiatal hernia or hiatus hernia is a type of hernia in which abdominal organs (typically the stomach) slip through the diaphragm into the middle compartment of the chest. This may result in gastroesophageal reflux disease (GERD) or laryng ...

, certain medications, and certain foods. Diagnosis is usually based on symptoms and medical history, with further testing only after treatment has been ineffective. Further diagnosis can be achieved by

measuring Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to ...

how much acid enters the esophagus or looking into the esophagus with a

scope Scope or scopes may refer to: People with the surname * Jamie Scope (born 1986), English footballer * John T. Scopes (1900–1970), central figure in the Scopes Trial regarding the teaching of evolution Arts, media, and entertainment * CinemaS ...

. Treatment and management options include lifestyle modifications, medications, and surgery if there is no improvement with other interventions. Lifestyle modifications include not lying down for three hours after eating, lying down on the left side, elevating head while laying by elevating head of the bed or using extra pillows, losing weight, stopping smoking, and avoiding coffee, mint, alcohol, chocolate, fatty foods, acidic foods, and spicy foods. Medications include

antacid An antacid is a substance which neutralization (chemistry), neutralizes gastric acid, stomach acidity and is used to relieve heartburn, indigestion, or an upset stomach. Some antacids have been used in the treatment of constipation and diarrhe ...

proton pump inhibitors Proton-pump inhibitors (PPIs) are a class of medications that cause a profound and prolonged reduction of gastric acid, stomach acid production. They do so by irreversibly inhibiting the stomach's H+/K+ ATPase, H+/K+ ATPase proton pump. The body ...

, H2 receptor blockers. Surgery is usually a

Nissen fundoplication A Nissen fundoplication, or laparoscopic Nissen fundoplication when performed via laparoscopic surgery, is a surgical procedure to treat gastroesophageal reflux disease (GERD) and hiatal hernia. In GERD, it is usually performed when medical thera ...

and is performed by a surgeon. Complications of longstanding GERD can include inflammation of the esophagus that may cause bleeding or ulcer formation, narrowing of the esophagus leading to swallowing issues, a change in the lining of the esophagus that can increase the chances of developing cancer (

), chronic cough, asthma, inflammation of the larynx leading to hoarseness, and wearing away of tooth enamel leading to dental issues.

Barrett's esophagus

A condition in which the lining of the esophagus changes to look more like the lining of the intestine and increases the risk of developing

esophageal cancer Esophageal cancer (American English) or oesophageal cancer (British English) is cancer arising from the esophagus—the food pipe that runs between the throat and the stomach. Symptoms often include dysphagia, difficulty in swallowing and weigh ...

. There are no specific symptoms although symptoms of GERD may be present for years prior as it is associated with a 10–15% risk of Barrett's esophagus. Risk factors include chronic GERD for more than 5 years, being age 50 or older, being non-Hispanic white, being male, having a family history of this disorder, belly fat, and a history of smoking. Diagnosis can be made by looking into the esophagus with a

and possibly taking a

of the lining of the esophagus. Treatment includes managing GERD, destroying abnormal parts of the esophagus, removing abnormal tissue in the esophagus, and removing part of the esophagus as performed by a general surgeon. Further management could include periodic surveillance with repeat scopes at certain intervals determined by the physician, likely not more frequently than every three to five years. Complications from this disorder can result in a type of cancer called

esophageal adenocarcinoma Esophageal can refer to: * The esophagus * Esophageal arteries * Esophageal glands * Esophageal cancer Esophageal cancer (American English) or oesophageal cancer (British English) is cancer arising from the esophagus—the food pipe that run ...

Education and training

United States

Gastroenterology is a subspecialty of internal medicine and therefore requires three years of

internal medicine Internal medicine, also known as general medicine in Commonwealth nations, is a medical specialty for medical doctors focused on the prevention, diagnosis, and treatment of diseases in adults. Its namesake stems from "treatment of diseases of ...

residency training Residency or postgraduate training is a stage of graduate medical education. It refers to a qualified physician (one who holds the degree of MD, DO, MBBS/MBChB), veterinarian ( DVM/VMD, BVSc/BVMS), dentist ( DDS or DMD), podiatrist ( DPM), o ...

followed by three additional years in a dedicated gastroenterology

fellowship A fellow is a title and form of address for distinguished, learned, or skilled individuals in academia, medicine, research, and industry. The exact meaning of the term differs in each field. In learned or professional societies, the term refers ...

. This training is certified by the

American Board of Internal Medicine The American Board of Internal Medicine (ABIM) is a 501(c)(3) nonprofit, self-appointed physician-evaluation organization that certifies physicians practicing internal medicine and its subspecialties. The American Board of Internal Medicine is no ...

(ABIM) and the

American Osteopathic Board of Internal Medicine The American Osteopathic Board of Internal Medicine (AOBIM) is an organization that provides board certification to qualified Doctors of Osteopathic Medicine (D.O.) who specialize in the prevention, diagnosis, and treatment of disease in adults ( ...

(AOBIM) and must be completed at a program accredited by the

Accreditation Council for Graduate Medical Education The Accreditation Council for Graduate Medical Education (ACGME) is the body responsible for accrediting all graduate medical training programs —internships, residencies, and fellowships (subspecialty programs) — for physicians in the United ...

(ACGME). Other national societies that oversee training include the

American College of Gastroenterology The American College of Gastroenterology (ACG) is a Bethesda, Maryland–based medical association of gastroenterologists. The association was founded in 1932 and holds annual meetings and regional postgraduate continuing education courses, est ...

(ACG), the

American Gastroenterological Association The American Gastroenterological Association (AGA) is a medical association of gastroenterologists. Approximately 16,000 scientists and physicians are members of the organization. Overview The American Gastroenterological Association is a prof ...

(AGA), and the

American Society for Gastrointestinal Endoscopy The American Society for Gastrointestinal Endoscopy (ASGE) is a professional organization of physicians dedicated to improving endoscopy. The ASGE is made up largely of gastroenterologists from the United States. Included in its membership are en ...

(ASGE).

Scope of practice

Gastroenterologists see patients both in the clinic and the hospital setting. They can order diagnostic tests, prescribe medications, and perform a number of diagnostic and

therapeutic A therapy or medical treatment is the attempted remediation of a health problem, usually following a medical diagnosis. Both words, ''treatment'' and ''therapy'', are often abbreviated tx, Tx, or Tx. As a rule, each therapy has indications an ...

procedures including

colonoscopy Colonoscopy () or coloscopy () is a medical procedure involving the Endoscopy, endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a Charge-coupled device, CCD ...

esophagogastroduodenoscopy Esophagogastroduodenoscopy (EGD) or oesophagogastroduodenoscopy (OGD), also called by various other names, is a diagnostic endoscopic procedure that visualizes the upper part of the gastrointestinal tract down to the duodenum. It is considered ...

(EGD),

endoscopic retrograde cholangiopancreatography Endoscopic retrograde cholangiopancreatography (ERCP) is a technique that combines the use of endoscopy An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior ...

(ERCP),

endoscopic ultrasound Endoscopic ultrasound (EUS) or echo-endoscopy is a medical procedure in which endoscopy (insertion of a probe into a hollow organ) is combined with ultrasound to obtain images of the internal organs in the chest, abdomen and colon. It can be used ...

(EUS), and

liver biopsy Liver biopsy is the biopsy (removal of a small sample of tissue) from the liver. It is a medical test that is done to aid diagnosis of liver disease, to assess the severity of known liver disease, and to monitor the progress of treatment. Medica ...

. In Gastroenterology, as in other specialties,

telehealth Telehealth is the distribution of Health care, health-related services and information via electronic information and telecommunications, telecommunication technologies. It allows long-distance patient and clinician contact, care, advice, reminde ...

has lead to a reshaping of healthcare systems by introducing new ways of providing care, facilitating access to services throughout the entire Countries.

Subspecialties

Some gastroenterology trainees will complete a "fourth-year" (although this is often their seventh year of graduate medical education) in transplant

hepatology Hepatology is the branch of medicine that incorporates the study of liver, gallbladder, biliary tree, and pancreas as well as management of their disorders. Although traditionally considered a sub-specialty of gastroenterology, rapid expansion ...

, advanced interventional

inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

motility Motility is the ability of an organism to move independently using metabolism, metabolic energy. This biological concept encompasses movement at various levels, from whole organisms to cells and subcellular components. Motility is observed in ...

, or other topics. Advanced endoscopy, sometimes called interventional or surgical endoscopy, is a sub-specialty of gastroenterology that focuses on advanced endoscopic techniques for the treatment of

pancreatic The pancreas (plural pancreases, or pancreata) is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine ...

hepatobiliary The biliary tract (also biliary tree or biliary system) refers to the liver, gallbladder and bile ducts, and how they work together to make, store and secrete bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids and ...

, and

gastrointestinal disease Gastrointestinal diseases (abbrev. GI diseases or GI illnesses) refer to diseases involving the Human gastrointestinal tract, gastrointestinal tract, namely the esophagus, stomach, small intestine, large intestine and rectum; and the accessory or ...

. Interventional gastroenterologists typically undergo an additional year of rigorous training in advanced endoscopic techniques including endoscopic retrograde cholangiopancreatography, endoscopic ultrasound-guided diagnostic and interventional procedures, and advanced resection techniques including

endoscopic mucosal resection Endoscopic mucosal resection is a technique used to remove cancerous or other abnormal lesions found in the digestive tract. It is one method of performing a mucosectomy. For the esophagous Endoscopic mucosal resection has been advocated for e ...

and

endoscopic submucosal dissection Endoscopic submucosal dissection (ESD) is an advanced surgical procedure using endoscopy to remove gastrointestinal tumors that have not entered the muscle layer. ESD may be done in the esophagus, stomach or colon. Application of endoscopic rese ...

. Additionally, the performance of endoscopic bariatric procedures is also performed by some advanced endoscopists.

Hepatology Hepatology is the branch of medicine that incorporates the study of liver, gallbladder, biliary tree, and pancreas as well as management of their disorders. Although traditionally considered a sub-specialty of gastroenterology, rapid expansion ...

, or hepatobiliary medicine, encompasses the study of the

, and

biliary tree The biliary tract (also biliary tree or biliary system) refers to the liver, gallbladder and bile ducts, and how they work together to make, store and secrete bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids a ...

, and is traditionally considered a sub-specialty of gastroenterology, while

encompasses disorders of the

, and colon and is considered a sub-specialty of

general surgery General surgery is a Surgical specialties, surgical specialty that focuses on alimentary canal and Abdomen, abdominal contents including the esophagus, stomach, small intestine, large intestine, liver, pancreas, gallbladder, Appendix (anatomy ...

Professional organizations

(ACG) - was founded in 1932 by a group of 10 gastroenterologists in New York City and now consists of over 16,000 gastroenterologists from 86 countries. The ACG sponsors conferences regionally and nationally, publishes several journals including ''

The American Journal of Gastroenterology ''The American Journal of Gastroenterology'' is a peer-reviewed medical journal owned by the American College of Gastroenterology. It has been published by Lippincott Williams & Wilkins since 2019 and was previously published by Nature Research, Bl ...

, Clinical and Translational Gastroenterology, and ACG Case Reports Journal,'' hosts

continuing medical education Continuing medical education (CME) is continuing education (CE) that helps those in the medical field maintain competence and learn about new and developing areas of their field. These activities may take place as live events, written publications ...

(CME) programs, supports initiatives for fellows-in-training, develops and promotes evidence-based guidelines, supports advocacy and public policy, and provides clinical research funding consisting of $27 million in research grants and career development awards ($2.2 million in 2022). *

(AGA) - was founded in 1897 and now includes over 16,000 members worldwide. Their mission statement reads "''Empowering clinicians and researchers to improve digestive health''." The AGA publishes two journals monthly titled ''

Gastroenterology Gastroenterology (from the Greek gastḗr- "belly", -énteron "intestine", and -logía "study of") is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometime ...

'' and ''

Clinical Gastroenterology and Hepatology ''Clinical Gastroenterology and Hepatology'' is a monthly peer-reviewed medical journal published by Elsevier on behalf of the American Gastroenterological Association. It was established in January 2003. According to the ''Journal Citation Repor ...

'', sponsors an annual meeting called Digestive Disease Week (DDW), provides more than $3 million each year in research grants to over 50 investigators through the AGA Research Foundation Awards Program ($2.56 million to 61 investigators in 2022), develops and promotes evidence-based guidelines, influences public policy through AGA's Congressional Advocates Program and the AGA political action committee (PAC), and supports a variety of educational opportunities including those that qualify for continuing medical education (CME) and maintenance of certification (MOC) credits. *

(ASGE) - was founded in 1941 and now includes around 15,000 members worldwide. Their mission statement reads "''The American Society for Gastrointestinal Endoscopy is the global leader in advancing digestive care through education, advocacy and promotion of excellence and innovation in endoscopy''." The ASGE publishes a monthly journal titled ''

Gastrointestinal Endoscopy ''Gastrointestinal Endoscopy'' is a monthly peer-reviewed medical journal covering gastroenterology, especially as relating to endoscopy. It is published by Elsevier and the official publication of the American Society for Gastrointestinal Endosc ...

'' (''GIE''), develops and promotes evidence-based guidelines, offers educational resources for its members, and provides advocacy resources for influencing public policy. *

World Gastroenterology Organisation The World Gastroenterology Organisation (WGO) is an international federation of over 100 national GI societies and 4 regional associations of gastroenterology representing over 50,000 individual members. WGO is focused on "the improvement of stan ...

(WGO) - was founded in 1958 and consists of 119 Member Societies and 4 regional affiliated associations from around the world which represents a combined 60,000 individuals. The WGO mission statement reads "''To promote, to the general public and healthcare professional alike, an awareness of the worldwide prevalence and optimal care of gastrointestinal and liver disorders, and to improve care of these disorders, through the provision of high quality, accessible and independent education and training''." The WGO publishes a newsletter titled the electronic World Gastroenterology News (''e-WGN''), develops global guidelines, engages in advocacy through World Digestive Health Day (WDHD) held yearly on 29 May, and provides educational resources including 23 training centers around the world and a Train the Trainers (TTT) program. *

British Society of Gastroenterology The British Society of Gastroenterology (BSG) is a British professional organisation of gastroenterologists, surgeons, pathologists, radiologists, scientists, nurses, dietitians and others amongst its members, which number over 4,000. It was founde ...

* United European Gastroenterology The United European Gastroenterology (UEG) was formally established in 1992. Over the years, UEG has grown significantly, establishing itself as a leading and prestigious medical specialty organization worldwide. UEG's mission is to advance the field of digestive diseases through prevention, research, diagnosis, treatment, and increased awareness. It unites over 50,000 professionals, including members from national and specialist societies, individual experts, and scientists in digestive health. UEG organizes the annual UEG Week, a major international gastroenterology congress. It also focuses on education, research support, and advocating for clinical standards and public health policies related to digestive diseases in Europe. UEG publishes the UEG Journal and the UEG White Book, which analyzes the burden and economic impact of digestive diseases in Europe.

Academic journals

* ''

'' * ''

Endoscopy An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are insert ...

'' * ''

'' * '' Gut'' * ''

Inflammatory Bowel Diseases Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

'' * ''

Journal of Clinical Gastroenterology ''Journal of Clinical Gastroenterology'' is a peer-reviewed medical journal covering gastroenterology and hepatology, published by Lippincott Williams & Wilkins. It was established in 1979 and the current editor-in-chief is Ronnie Fass, MD (Case We ...

'' * '' Journal of Crohn's and Colitis'' * '' Neurogastroenterology & Motility'' * ''

World Journal of Gastroenterology ''World Journal of Gastroenterology'' is a weekly peer-reviewed open access medical journal that covers research in gastroenterology. It was established in 1995 and is published by Baishideng Publishing Group. The editor-in-chief is Andrzej S. Tarn ...

References

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