Duodenum Health Dictionary

A stomach or duodenal ulcer, caused by excess or untimely secretions of gastric acid and pepsin, poor closure of the pyloric sphincter and digestive acid leakage into the duodenum, or poorly mucin-protected membranes resulting from infection or allergen irritation... peptic ulcer

This is a gland situated above the navel in the abdominal cavity that extends from the left side to the center, with its head tucked into the curve of the duodenum. It is 6-8 inches long, weighs 3 or 4 ounces, secretes pancreatic enzymes and alkali into the duodenum in concert with the gallbladder and liver, and secretes the hormones insulin and glucagon into the blood. Insulin acts to facilitate the absorption of blood glucose into fuel-needing cells, and glucagon stimulates a slow release of glucose from the liver, primarily to supply fuel to the brain. That most cherished organ uses one-quarter of the sugar in the blood and has no fuel storage. Pancreatic enzymes are basically those that digest fats, carbohydrates and proteins into their smaller components of fatty acids+glycerol, maltose, and amino acids...as well as curdling milk (thought you might want to know).... pancreas

The hormone (see HORMONES) released from the lining membrane of the DUODENUM when food is taken, and which initiates emptying of the gall-bladder (see LIVER).... cholecystokinin

This disorder is related to gastric ulcer (see STOMACH, DISEASES OF), both being a form of chronic peptic ulcer. Although becoming less frequent in western communities, peptic ulcers still affect around 10 per cent of the UK population at some time. Duodenal ulcers are 10–15 times more common than gastric ulcers, and occur in people aged from 20 years onwards. The male to female ratio for duodenal ulcer varies between 4:1 and 2:1 in di?erent communities. Social class and blood groups are also in?uential, with duodenal ulcer being more common among the upper social classes, and those of blood group O.

Causes It is likely that there is some abrasion, or break, in the lining membrane (or mucosa) of the stomach and/or duodenum, and that it is gradually eroded and deepened by the acidic gastric juice. The bacterium helicobacter pylori is present in the antrum of the stomach of people with peptic ulcers; 15 per cent of people infected with the bacterium develop an ulcer, and the ulcers heal if H. pylori is eradicated. Thus, this organism has an important role in creating ulcers. Mental stress may possibly be a provocative factor. Smoking seems to accentuate, if not cause, duodenal ulcer, and the drinking of alcohol is probably harmful. The apparent association with a given blood group, and the fact that relatives of a patient with a peptic ulcer are unduly likely to develop such an ulcer, suggest that there is some constitutional factor.

Symptoms and signs Peptic ulcers may present in di?erent ways, but chronic, episodic pain lasting several months or years is most common. Occasionally, however, there may be an acute episode of bleeding or perforation, or obstruction of the gastric outlet, with little previous history. Most commonly there is pain of varying intensity in the middle or upper right part of the abdomen. It tends to occur 2–3 hours after a meal, most commonly at night, and is relieved by some food such as a glass of milk; untreated it may last up to an hour. Vomiting is unusual, but there is often tenderness and sti?ness (‘guarding’) of the abdominal muscles. Con?rmation of the diagnosis is made by radiological examination (‘barium meal’), the ulcer appearing as a niche on the ?lm, or by looking at the ulcer directly with an endoscope (see FIBREOPTIC ENDOSCOPY). Chief complications are perforation of the ulcer, leading to the vomiting of blood, or HAEMATEMESIS; or less severe bleeding from the ulcer, the blood passing down the gut, resulting in dark, tarry stools (see MELAENA).

Treatment of a perforation involves initial management of any complications, such as shock, haemorrhage, perforation, or gastric outlet obstruction, usually involving surgery and blood replacement. Medical treatment of a chronic ulcer should include regular meals, and the avoidance of fatty foods, strong tea or co?ee and alcohol. Patients should also stop smoking and try to reduce the stress in their lives. ANTACIDS may provide symptomatic relief. However, the mainstay of treatment involves four- to six-week courses with drugs such as CIMETIDINE and RANITIDINE. These are H2 RECEPTOR ANTAGONISTS which heal peptic ulcers by reducing gastric-acid output. Of those relapsing after stopping this treatment, 60–95 per cent have infection with H. pylori. A combination of BISMUTH chelate, amoxycillin (see PENICILLIN; ANTIBIOTICS) and METRONIDAZOLE – ‘triple regime’ – should eliminate the infection: most physicians advise the triple regime as ?rst-choice treatment because it is more likely to eradicate Helicobacter and this, in turn, enhances healing of the ulcer or prevents recurrence. Surgery may be necessary if medical measures fail, but its use is much rarer than before e?ective medical treatments were developed.... duodenal ulcer

Narrowing of the PYLORUS, the muscular exit from the STOMACH. It is usually the result of a pyloric ulcer or cancer near the exit of the stomach. Food is delayed when passing from the stomach to the duodenum and vomiting occurs. The stomach may become distended and peristalsis (muscular movement) may be seen through the abdominal wall. Unless surgically treated the patient will steadily deteriorate, losing weight, becoming dehydrated and developing ALKALOSIS.

A related condition, congenital hypertrophic pyloric stenosis, occurs in babies (commonly boys) about 3–5 weeks old, and surgery produces a complete cure.... pyloric stenosis

A hormone (see HORMONES) secreted by the mucous membrane of the duodenum, the ?rst part of the small INTESTINE, when food comes in contact with it. On being carried by the blood to the PANCREAS, it stimulates the secretion of pancreatic juice.... secretin

All the alimentary canal beyond below the stomach. In it, most DIGESTION is carried on, and through its walls all the food material is absorbed into the blood and lymph streams. The length of the intestine in humans is about 8·5–9 metres (28–30 feet), and it takes the form of one continuous tube suspended in loops in the abdominal cavity.

Divisions The intestine is divided into small intestine and large intestine. The former extends from the stomach onwards for 6·5 metres (22 feet) or thereabouts. The large intestine is the second part of the tube, and though shorter (about 1·8 metres [6 feet] long) is much wider than the small intestine. The latter is divided rather arbitrarily into three parts: the duodenum, consisting of the ?rst 25–30 cm (10–12 inches), into which the ducts of the liver and pancreas open; the jejunum, comprising the next 2·4–2·7 metres (8–9 feet); and ?nally the ileum, which at its lower end opens into the large intestine.

The large intestine begins in the lower part of the abdomen on the right side. The ?rst part is known as the caecum, and into this opens the appendix vermiformis. The appendix is a small tube, closed at one end and about the thickness of a pencil, anything from 2 to 20 cm (average 9 cm) in length, which has much the same structure as the rest of the intestine. (See APPENDICITIS.) The caecum continues into the colon. This is subdivided into: the ascending colon which ascends through the right ?ank to beneath the liver; the transverse colon which crosses the upper part of the abdomen to the left side; and the descending colon which bends downwards through the left ?ank into the pelvis where it becomes the sigmoid colon. The last part of the large intestine is known as the rectum, which passes straight down through the back part of the pelvis, to open to the exterior through the anus.

Structure The intestine, both small and large, consists of four coats, which vary slightly in structure and arrangement at di?erent points but are broadly the same throughout the entire length of the bowel. On the inner surface there is a mucous membrane; outside this is a loose submucous coat, in which blood vessels run; next comes a muscular coat in two layers; and ?nally a tough, thin peritoneal membrane. MUCOUS COAT The interior of the bowel is completely lined by a single layer of pillar-like cells placed side by side. The surface is increased by countless ridges with deep furrows thickly studded with short hair-like processes called villi. As blood and lymph vessels run up to the end of these villi, the digested food passing slowly down the intestine is brought into close relation with the blood circulation. Between the bases of the villi are little openings, each of which leads into a simple, tubular gland which produces a digestive ?uid. In the small and large intestines, many cells are devoted to the production of mucus for lubricating the passage of the food. A large number of minute masses, called lymph follicles, similar in structure to the tonsils are scattered over the inner surface of the intestine. The large intestine is bare both of ridges and of villi. SUBMUCOUS COAT Loose connective tissue which allows the mucous membrane to play freely over the muscular coat. The blood vessels and lymphatic vessels which absorb the food in the villi pour their contents into a network of large vessels lying in this coat. MUSCULAR COAT The muscle in the small intestine is arranged in two layers, in the outer of which all the ?bres run lengthwise with the bowel, whilst in the inner they pass circularly round it. PERITONEAL COAT This forms the outer covering for almost the whole intestine except parts of the duodenum and of the large intestine. It is a tough, ?brous membrane, covered upon its outer surface with a smooth layer of cells.... intestine

This is a distensible, sac-like organ with an average adult capacity of 1·5 litres situated in the upper abdomen. It is positioned between the OESOPHAGUS and DUODENUM, lying just beneath the DIAPHRAGM to the right of the SPLEEN and partly under the LIVER. The stomach is a part of the gastrointestinal tract with its walls formed of layers of longitudinal and circular muscles and lined by glandular cells that secrete gastric juice. It is well supplied with blood vessels as well as nerves from the autonomic system which enter via the phrenic nerve. The exit of the stomach is guarded by a ring of muscle called the pyloric sphincter which controls the passage of food into the duodenum.

Function As well as the stomach’s prime role in physically and physiologically breaking down the food delivered via the oesophagus, it also acts as a storage organ – a function that enables people to eat three or four times a day instead of every 30 minutes or so as their metabolic needs would otherwise demand. Gastric secretion is stimulated by the sight and smell of food and its subsequent arrival in the stomach. The secretions, which contain mucus and hydrochloric acid (the latter produced by parietal cells), sterilise the food; pepsin, a digestive ENZYME in the gastric juices, breaks down the protein in food. The juices also contain intrinsic factor, vital for the absorption of vitamin B12 when the chyle – as the stomach contents are called – reaches the intestine. This chyle is of creamy consistency and is the end product of enzymic action and rhythmic contractions of the stomach’s muscles every 30 seconds or so. Food remains in the stomach for varying lengths of time depending upon its quantity and nature. At regular intervals a bolus of chyle is forced into the duodenum by contractions of the stomach muscles coordinated with relaxation of the pyloric sphincter.... stomach

The channel running from the gall-bladder (see LIVER) to the DUODENUM; carries BILE.... bile duct

A surgical operation to join the DUODENUM to a hole made in the STOMACH wall to circumvent an obstruction in the gut – for example, PYLORIC STENOSIS – or to improve the passage of food from the stomach into the duodenum.... gastroduodenostomy

A condition caused by a parasitic organism known as Giardia lamblia, which is found in the duodenum (see INTESTINE) and the upper part of the small intestine. This organism is usually harmless, but is sometimes responsible for causing diarrhoea. The illness develops one or two weeks after exposure to infection, and usually starts as an explosive diarrhoea, with the passage of pale fatty stools, abdominal pain and nausea. It responds well to METRONIDAZOLE or MEPACRINE.... giardiasis

A major operation to remove the whole or part of the STOMACH. Total gastrectomy is a rare operation, usually performed when a person has cancer of the stomach; the OESPHAGUS is then connected to the DUODENUM. Sometimes cancer of the stomach can be treated by doing a partial gastrectomy: the use of partial gastrectomy to treat PEPTIC ULCER used to be common before the advent of e?ective drug therapy.

The operation is sometimes still done if the patient has failed to respond to dietary treatment and treatment with H2-blocking drugs (see CIMETIDINE; RANITIDINE) along with antibiotics to combat Helicobacter pylori, an important contributary factor to ulcer development. Partial gastrectomy is usually accompanied by VAGOTOMY, which involves cutting the VAGUS nerve controlling acid secretion in the stomach. Among the side-effects of gastrectomy are fullness and discomfort after meals; formation of ulcers at the new junction between the stomach and duodenum which may lead to GASTRITIS and oesophagitis (see OESOPHAGUS, DISEASES OF); dumping syndrome (nausea, sweating and dizziness because the food leaves the stomach too quickly after eating); vomiting and diarrhoea. The side-effects usually subside but may need dietary and drug treatment.... gastrectomy

The chief protein ENZYME of the pancreatic secretion. Secreted by the PANCREAS as trypsinogen (an inactive form), it is converted in the duodenum by another enzyme, enteropeptidase. It changes proteins into peptones and forms the main constituent of pancreatic extracts used for digestion of food. (See PEPTONISED FOODS.)... trypsin

Inflammation of the duodenum (first part of the small intestine), producing vague gastrointestinal symptoms. The condition is diagnosed by oesophagogastroduodenoscopy (see gastroscopy) which is the examination of the walls of the upper digestive tract with a flexible viewing instrument. Treatment is similar to that for a duodenal ulcer (see peptic ulcer).... duodenitis

The liver is the largest gland in the body, serving numerous functions, chie?y involving various aspects of METABOLISM.

Form The liver is divided into four lobes, the greatest part being the right lobe, with a small left lobe, while the quadrate and caudate lobes are two small divisions on the back and undersurface. Around the middle of the undersurface, towards the back, a transverse ?ssure (the porta hepatis) is placed, by which the hepatic artery and portal vein carry blood into the liver, and the right and left hepatic ducts emerge, carrying o? the BILE formed in the liver to the GALL-BLADDER attached under the right lobe, where it is stored.

Position Occupying the right-hand upper part of the abdominal cavity, the liver is separated from the right lung by the DIAPHRAGM and the pleural membrane (see PLEURA). It rests on various abdominal organs, chie?y the right of the two KIDNEYS, the suprarenal gland (see ADRENAL GLANDS), the large INTESTINE, the DUODENUM and the STOMACH.

Vessels The blood supply di?ers from that of the rest of the body, in that the blood collected from the stomach and bowels into the PORTAL VEIN does not pass directly to the heart, but is ?rst distributed to the liver, where it breaks up into capillary vessels. As a result, some harmful substances are ?ltered from the bloodstream and destroyed, while various constituents of the food are stored in the liver for use in the body’s metabolic processes. The liver also receives the large hepatic artery from the coeliac axis. After circulating through capillaries, the blood from both sources is collected into the hepatic veins, which pass directly from the back surface of the liver into the inferior vena cava.

Minute structure The liver is enveloped in a capsule of ?brous tissue – Glisson’s capsule – from which strands run along the vessels and penetrate deep into the organ, binding it together. Subdivisions of the hepatic artery, portal vein, and bile duct lie alongside each other, ?nally forming the interlobular vessels,

which lie between the lobules of which the whole gland is built up. Each is about the size of a pin’s head and forms a complete secreting unit; the liver is built up of hundreds of thousands of such lobules. These contain small vessels, capillaries, or sinusoids, lined with stellate KUPFFER CELLS, which run into the centre of the lobule, where they empty into a small central vein. These lobular veins ultimately empty into the hepatic veins. Between these capillaries lie rows of large liver cells in which metabolic activity occurs. Fine bile capillaries collect the bile from the cells and discharge it into the bile ducts lying along the margins of the lobules. Liver cells are among the largest in the body, each containing one or two large round nuclei. The cells frequently contain droplets of fat or granules of GLYCOGEN – that is, animal starch.

Functions The liver is, in e?ect, a large chemical factory and the heat this produces contributes to the general warming of the body. The liver secretes bile, the chief constituents of which are the bile salts (sodium glycocholate and taurocholate), the bile pigments (BILIRUBIN and biliverdin), CHOLESTEROL, and LECITHIN. These bile salts are collected and formed in the liver and are eventually converted into the bile acids. The bile pigments are the iron-free and globin-free remnant of HAEMOGLOBIN, formed in the Kup?er cells of the liver. (They can also be formed in the spleen, lymph glands, bone marrow and connective tissues.) Bile therefore serves several purposes: it excretes pigment, the breakdown products of old red blood cells; the bile salts increase fat absorption and activate pancreatic lipase, thus aiding the digestion of fat; and bile is also necessary for the absorption of vitamins D and E.

The other important functions of the liver are as follows:

In the EMBRYO it forms red blood cells, while the adult liver stores vitamin B12, necessary for the proper functioning of the bone marrow in the manufacture of red cells.

It manufactures FIBRINOGEN, ALBUMINS and GLOBULIN from the blood.

It stores IRON and copper, necessary for the manufacture of red cells.

It produces HEPARIN, and – with the aid of vitamin K – PROTHROMBIN.

Its Kup?er cells form an important part of the RETICULO-ENDOTHELIAL SYSTEM, which breaks down red cells and probably manufactures ANTIBODIES.

Noxious products made in the intestine and absorbed into the blood are detoxicated in the liver.

It stores carbohydrate in the form of glycogen, maintaining a two-way process: glucose

glycogen.

CAROTENE, a plant pigment, is converted to vitamin A, and B vitamins are stored.

It splits up AMINO ACIDS and manufactures UREA and uric acids.

It plays an essential role in the storage and metabolism of FAT.... liver

The middle, coiled section of the small intestine, joining the duodenum to the ileum.

The jejunum’s function is the digestion of food and absorption of nutrients.

It may be affected by coeliac disease, Crohn’s disease, and lymphoma.... jejunum

n. a drug that stimulates the flow of bile from the gall bladder and bile ducts into the duodenum.... cholagogue

A greenish-brown alkaline liquid secreted by the liver. Bile carries away waste products formed in the liver and also helps to break down fats in the small intestine for digestion.

The waste products in bile include the pigments bilirubin and biliverdin, which give bile its greenish-brown colour; bile salts, which aid in the breakdown and absorption of fats; and cholesterol. Bile passes out of the liver through the bile ducts and is then concentrated and stored in the gallbladder. After a meal, bile is expelled and enters the duodenum (the first section of the small intestine) via the common bile duct. Most of the bile salts are later reabsorbed into the bloodstream to be recycled by the liver into bile. Bile pigments are excreted in the faeces. (See also biliary system; colestyramine.)

bile duct Any of the ducts by which bile is carried from the liver, first to the gallbladder and then to the duodenum (the first section of the small intestine). The bile duct system forms a network of tubular canals. Canaliculi (small canals) surround the liver cells and collect the bile. The canaliculi join together to form ducts of increasing size. The ducts emerge from the liver as the 2 hepatic ducts, which join within or just outside the liver to form the common hepatic duct. The cystic duct branches off to the gallbladder; from this point the common hepatic duct becomes the common bile duct and leads into the duodenum.

(See also biliary system.)

bile duct cancer See cholangiocarcinoma. bile duct obstruction A blockage or constriction of a bile duct (see biliary system). Bile duct obstruction results in accumulation of bile in the liver (cholestasis) and jaundice due to a buildup of bilirubin in the blood. Prolonged obstruction of the bile duct can lead to secondary biliary cirrhosis. The most common cause of obstruction is gallstones. Other causes include a tumour affecting the pancreas (see pancreas, cancer of), where the bile duct passes through it, or cancer that has spread from elsewhere in the body. Cholangiocarcinoma (cancer of the bile ducts) is a very rare cause of blockage. Bile duc.

obstruction is a rare side effect of certain drugs. It may also be caused by cholangitis (inflammation of the bile ducts), trauma (such as injury during surgery), and rarely by flukes or worms.

Bile duct obstruction causes “obstructive” jaundice, which is characterized by pale-coloured faeces, dark urine, and a yellow skin colour.

There may also be itching.

Other symptoms may include abdominal pain (with gallstones) or weight loss (with cancer).

Treatment depends on the cause, but surgery may be necessary.

Gallstones may be removed with an endoscope (see ERCP).... bile

See under STOMACH, DISEASES OF; INTESTINE, DISEASES OF; DIARRHOEA; LIVER, DISEASES OF; PANCREAS, DISEASES OF; GALL-BLADDER, DISEASES OF; KIDNEYS, DISEASES OF; URINARY BLADDER, DISEASES OF; HERNIA; PERITONITIS; APPENDICITIS; TUMOUR.

Various processes that can occur include in?ammation, ulceration, infection or tumour. Abdominal disease may be of rapid onset, described as acute, or more long-term when it is termed chronic.

An ‘acute abdomen’ is most commonly caused by peritonitis – in?ammation of the membrane that lines the abdomen. If any structure in the abdomen gets in?amed, peritonitis may result. Causes include injury, in?ammation of the Fallopian tubes (SALPINGITIS), and intestinal disorders such as APPENDICITIS, CROHN’S DISEASE, DIVERTICULITIS or a perforated PEPTIC ULCER. Disorders of the GALLBLADDER or URINARY TRACT may also result in acute abdominal pain.

General symptoms of abdominal disease include:

Pain This is usually ill-de?ned but can be very unpleasant, and is termed visceral pain. Pain is initially felt near the mid line of the abdomen. Generally, abdominal pain felt high up in the mid line originates from the stomach and duodenum. Pain that is felt around the umbilicus arises from the small intestine, appendix and ?rst part of the large bowel, and low mid-line pain comes from the rest of the large bowel. If the diseased organ secondarily in?ames or infects the lining of the abdominal wall – the PERITONEUM – peritonitis occurs and the pain becomes more de?ned and quite severe, with local tenderness over the site of the diseased organ itself. Hence the pain of appendicitis begins as a vague mid-line pain, and only later moves over to the right iliac fossa, when the in?amed appendix has caused localised peritonitis. PERFORATION of one of the hollow organs in the abdomen – for example, a ruptured appendix or a gastric or duodenal ulcer (see STOMACH, DISEASES OF) eroding the wall of the gut – usually causes peritonitis with resulting severe pain.

The character of the pain is also important. It may be constant, as occurs in in?ammatory diseases and infections, or colicky (intermittent) as in intestinal obstruction.

Swelling The commonest cause of abdominal swelling in women is pregnancy. In disease, swelling may be due to the accumulation of trapped intestinal contents within the bowel, the presence of free ?uid (ascites) within the abdomen, or enlargement of one or more of the abdominal organs due to benign causes or tumour.

Constipation is the infrequent or incomplete passage of FAECES; sometimes only ?atus can be passed and, rarely, no bowel movements occur (see main entry for CONSTIPATION). It is often associated with abdominal swelling. In intestinal obstruction, the onset of symptoms is usually rapid with complete constipation and severe, colicky pain. In chronic constipation, the symptoms occur more gradually.

Nausea and vomiting may be due to irritation of the stomach, or to intestinal obstruction when it may be particularly foul and persistent. There are also important non-abdominal causes, such as in response to severe pain or motion sickness.

Diarrhoea is most commonly due to simple and self-limiting infection, such as food poisoning, but may also indicate serious disease, especially if it is persistent or contains blood (see main entry for DIARRHOEA).

Jaundice is a yellow discoloration of the skin and eyes, and may be due to disease in the liver or bile ducts (see main entry for JAUNDICE).

Diagnosis and treatment Abdominal diseases are often di?cult to diagnose because of the multiplicity of the organs contained within the abdomen, their inconstant position and the vagueness of some of the symptoms. Correct diagnosis usually requires experience, often supplemented by specialised investigations such as ULTRASOUND. For this reason sufferers should obtain medical advice at an early stage, particularly if the symptoms are severe, persistent, recurrent, or resistant to simple remedies.... abdomen, diseases of

Also called regional enteritis or regional ileitis, this is a nonspecific inflammatory disease of the upper and lower intestine that forms granulated lesions. It is usually a chronic condition, with acute episodes of diarrhea, abdominal pain, loss of appetite, and loss of weight. It may affect the stomach or colon, but the most common sites are the duodenum and the lowest part of the small intestine, the lower ileum. The standard treatment is, initially, anti-inflammatory drugs, with surgical resectioning often necessary. The disease is autoimmune, and sufferers share the same tissue type (HLA-B27) as those who acquire ankylosing spondylitis.... crohn’s disease

The name applied to a passage leading from a gland into some hollow organ, or on to the surface of the body, by which the secretion of the gland is discharged: for example, the pancreatic duct and the bile duct opening into the duodenum, and the sweat ducts opening on the skin surface.... duct

Dilatation of the DUODENUM due to its chronic obstruction, caused by an abnormal position of arteries in the region of the duodenum pressing on it.... duodenal ileus

The ENZYME secreted in the DUODENUM and jejunum (see INTESTINE) which converts the enzyme, trypsinogen, secreted by the PANCREAS, into TRYPSIN. (See also DIGESTION.)... enterokinase

In?ammation of the STOMACH lining. This may take an acute form when excess alcohol or other irritating substances have been taken, resulting in vomiting. Chronic gastritis may be the result of regular smoking and chronic alcoholism, or the condition may be caused by the back ?ow of BILE from the DUODENUM. The common cause, however, is chronic infection with HELICOBACTER PYLORI. Symptoms are vague but victims are likely to develop gastric ulcers or sometimes cancer. Atrophic gastritis, when the mucosal lining of the stomach withers away, may follow chronic gastritis but sometimes occurs as an autoimmune disorder.... gastritis

A visualising technique enabling the operator to examine the internal organs with the minimum of disturbance or damage to the tissues. The procedure has transformed the management of, for example, gastrointestinal disease. In chest disease, ?breoptic bronchoscopy has now replaced the rigid wide-bore metal tube which was previously used for examination of the tracheo-bronchial tree.

The principle of ?breoptics in medicine is that a light from a cold light source passes down a bundle of quartz ?bres in the endoscope to illuminate the lumen of the gastrointestinal tract or the bronchi. The re?ected light is returned to the observer’s eye via the image bundle which may contain up to 20,000 ?bres. The tip of the instrument can be angulated in both directions, and ?ngertip controls are provided for suction, air insu?ation and for water injection to clear the lens or the mucosa. The oesophagus, stomach and duodenum can be visualised; furthermore, visualisation of the pancreatic duct and direct endoscopic cannulation is now possible, as is visualisation of the bile duct. Fibreoptic colonoscopy can visualise the entire length of the colon and it is now possible to biopsy polyps or suspected carcinomas and to perform polypectomy.

The ?exible smaller ?breoptic bronchoscope has many advantages over the rigid tube, extending the range of view to all segmental bronchi and enabling biopsy of pulmonary parenchyma. Biopsy forceps can be directed well beyond the tip of the bronchoscope itself, and the more ?exible ?breoptic instrument causes less discomfort to the patient.

Fibreoptic laparoscopy is a valuable technique that allows the direct vizualisation of the abdominal contents: for example, the female pelvic organs, in order to detect the presence of suspected lesions (and, in certain cases, e?ect their subsequent removal); check on the development and position of the fetus; and test the patency of the Fallopian tubes.

(See also ENDOSCOPE; BRONCHOSCOPE; LARYNGOSCOPE; LAPAROSCOPE; COLONOSCOPE.)... fibreoptic endoscopy

Motilin is a hormone (see HORMONES) formed in the DUODENUM and the JEJUNUM which plays a part in controlling the movements of the stomach and the gut.... motilin

The gall-bladder rests on the underside of the LIVER and joins the common hepatic duct via the cystic duct to form the common BILE DUCT. The gall-bladder acts as a reservoir and concentrator of BILE, alterations in the composition of which may result in the formation of gallstones, the most common disease of the gallbladder.

Gall-stones affect 22 per cent of women and 11 per cent of men. The incidence increases with age, but only about 30 per cent of those with gall-stones undergo treatment as the majority of cases are asymptomatic. There are three types of stone: cholesterol, pigment and mixed, depending upon their composition; stones are usually mixed and may contain calcium deposits. The cause of most cases is not clear but sometimes gall-stones will form around a ‘foreign body’ within the bile ducts or gall-bladder, such as suture material. BILIARY COLIC Muscle ?bres in the biliary system contract around a stone in the cystic duct or common bile duct in an attempt to expel it. This causes pain in the right upper quarter of the abdomen, with nausea and occasionally vomiting. JAUNDICE Gall-stones small enough to enter the common bile duct may block the ?ow of bile and cause jaundice. ACUTE CHOLECYSTITIS Blockage of the cystic duct may lead to this. The gall-bladder wall becomes in?amed, resulting in pain in the right upper quarter of the abdomen, fever, and an increase in the white-blood-cell count. There is characteristically tenderness over the tip of the right ninth rib on deep inhalation (Murphy’s sign). Infection of the gall-bladder may accompany the acute in?ammation and occasionally an EMPYEMA of the gall-bladder may result. CHRONIC CHOLECYSTITIS A more insidious form of gall-bladder in?ammation, producing non-speci?c symptoms of abdominal pain, nausea and ?atulence which may be worse after a fatty meal.

Diagnosis Stones are usually diagnosed on the basis of the patient’s reported symptoms, although asymptomatic gall-stones are often an incidental ?nding when investigating another complaint. Con?rmatory investigations include abdominal RADIOGRAPHY – although many gall-stones are not calci?ed and thus do not show up on these images; ULTRASOUND scanning; oral CHOLECYSTOGRAPHY – which entails a patient’s swallowing a substance opaque to X-rays which is concentrated in the gall-bladder; and endoscopic retrograde cholangiopancreatography (ERCP) – a technique in which an ENDOSCOPE is passed into the duodenum and a contrast medium injected into the biliary duct.

Treatment Biliary colic is treated with bed rest and injection of morphine-like analgesics. Once the pain has subsided, the patient may then be referred for further treatment as outlined below. Acute cholecystitis is treated by surgical removal of the gall-bladder. There are two techniques available for this procedure: ?rstly, conventional cholecystectomy, in which the abdomen is opened and the gall-bladder cut out; and, secondly, laparoscopic cholecystectomy, in which ?breoptic instruments called endoscopes (see FIBREOPTIC ENDOSCOPY) are introduced into the abdominal cavity via several small incisions (see MINIMALLY INVASIVE SURGERY (MIS)). Laparoscopic surgery has the advantage of reducing the patient’s recovery time. Gall-stones may be removed during ERCP; they can sometimes be dissolved using ultrasound waves (lithotripsy) or tablet therapy (dissolution chemotherapy). Pigment stones, calci?ed stones or stones larger than 15 mm in diameter are not suitable for this treatment, which is also less likely to succeed in the overweight patient. Drug treatment is prolonged but stones can disappear completely after two years. Stones may re-form on stopping therapy. The drugs used are derivatives of bile salts, particularly chenodeoxycholic acid; side-effects include diarrhoea and liver damage.... gall-bladder, diseases of

Spasm of the pyloric portion of the STOMACH. This interferes with the passage of food in a normal, gentle fashion into the intestine, causing the pain that comes on from half an hour to three hours after meals; it is associated with severe disorders of digestion. It is often produced by an ulcer of the stomach or duodenum.... pylorospasm

A soft rubber or plastic tube with rounded end, and usually about 75 cm (30 inches) in length, which is used for washing out the stomach when it contains some poisonous material. (See GASTRIC LAVAGE.) A narrower tube, 90 cm (36 inches) in length, is used to obtain a sample of gastric juice for examination. Such a tube can also be allowed to pass out of the stomach into the duodenum so that the contents of the upper part of the small intestine are similarly obtained for analysis.... stomach tube

A rare disorder in which severe peptic ulcers recur in the stomach and duodenum (see DUODENAL ULCER; STOMACH, DISEASES OF). It is caused by a tumour in the PANCREAS that produces a hormone, GASTRIN, which stimulates the stomach and duodenum to produce excess acid: this causes ulceration. Treatment is by surgery.... zollinger-ellison syndrome

A long fold of peritoneal membrane (see PERITONEUM), generally loaded with more or less fat, which hangs down within the cavity of the ABDOMEN in front of the bowels. It is formed by the layers of peritoneum that cover the front and back surfaces of the stomach in their passage from the lower margin of this organ to cover the back and front surfaces of the large intestine. Instead of passing straight from one organ to the other, these layers dip down and form a sort of fourfold apron. This omentum is known as the greater omentum, to distinguish it from two smaller peritoneal folds, one of which passes between the liver and stomach (the hepatogastric omentum), and the other between the liver and duodenum (the hepatoduodenal omentum). Together they are known as the lesser omentum.... omentum

Congenital absence or severe narrowing of a body opening or tubular organ, due to a failure of development in the uterus.

Examples are biliary atresia, in which the bile duct between the liver and duodenum are absent; oesophageal atresia, in which the oesophagus comes to a blind end; and anal atresia (see anus, imperforate), in which the anal canal is shut off.

Most forms of atresia require surgical correction early in life.... atresia

The abbreviation for endoscopic retrograde cholangiopancreatography, an X-ray procedure used for examining the biliary system and the pancreatic duct.

An endoscope is passed down the oesophagus, through the stomach, and into the duodenum.

A catheter is passed through the endoscope into the common bile duct and pancreatic duct.

A contrast medium is introduced through the catheter to make the pancreatic duct and ducts of the biliary system visible on X-rays.

In some cases, it may be possible to relieve a blockage due to a gallstone during the procedure.... ercp

A bacterium now known to be the cause of most peptic ulcers as well as a factor in stomach cancer. The bacterium is thought to damage the mucus layer of the stomach and duodenum, allowing gastric acid to cause ulceration. Treatment with antibiotics to eradicate the infection has proved successful in achieving long-term recovery from peptic ulcers.... helicobacter pylori

One of a group of fatty acids that is made naturally in the body and acts in a similar way to hormones. Prostaglandins cause pain and inflammation in damaged tissue, protect the lining of the stomach and duodenum against ulceration, lower blood pressure, and stimulate contractions in labour.

(See also prostaglandin drugs.)... prostaglandin

Inflammation of the kidney, usually as a result of a bacterial infection. Pyelonephritis is more common in women and is more likely to occur during pregnancy. Symptoms of pyelonephritis include a high fever, chills, and back pain. Septicaemia is a possible complication. Pyelonephritis is treated with antibiotic drugs.

pyloric sphincter The valve at the base of the stomach that controls movement of food into the duodenum.... pyelonephritis

A rare condition characterized by severe and recurrent peptic ulcers in the stomach, duodenum, and jejunum (the 2nd part of the small intestine). Zollinger–Ellison syndrome is caused by 1 or more tumours in the pancreas that secrete the hormone gastrin. Gastrin stimulates production of large quantities of acid by the stomach, which leads to ulceration. The high levels of acid in the digestive tract often also cause diarrhoea.

The tumours are cancerous, but of a slow-growing type.

If possible, they are removed surgically.

Proton pump inhibitor drugs are given to treat the ulcers.... zollinger–ellison syndrome

Destruction of the skin’s surface tissues resulting in an open sore. A similar breach may occur in the surface of the mucous membrane lining body cavities – for example, the stomach, duodenum or colon (see COLITIS). Usually accompanied by pain and local in?ammation, ulcers can be shallow or deep, with a crater-like shape. An ulcer may heal naturally, but on certain parts of the body – legs (venous ulcers, see below) or bony protuberances (decubitus ulcers, see below) – they can become chronic and di?cult to treat. When an ulcer heals, granulations (well-vascularised connective tissue) form which become ?brous and draw the edges of the ulcer together. Any damage to the body surface may develop into an ulcer if the causative agent is allowed to persist – for example, contact with a noxious substance or constant pressure on an area of tissue with poor circulation. Treatment of skin ulcers is e?ected by cleaning the area, regular dry dressings and local or systemic ANTIBIOTICS depending upon the severity of the ulcer.

Decubitus ulcer Also known as pressure or bed sore. Occurs when there is constant pressure on and inadequate oxygenation of an area of skin, usually overlying a bony protuberance. Elderly or in?rm people, or individuals with debilitating, emaciating or neurological illnesses, are vulnerable to the condition. Long-term pressure from a bed, wheelchair, cast or splint is the usual cause. Loss of skin sensation is a contributory factor, and muscle and bone as well as skin may be affected.

Treatment The most important treatment is prevention, keeping the patient’s back, buttocks, heels and other pressure-points clean and dry, and regularly changing his or her position. If ulcers do develop, repeated local DEBRIDEMENT, protective dressings and (in serious cases) surgical treatment are required, accompanied by an appropriate antibiotic if infection is persistent.

Venous ulcer This occurs on the lower leg or ankle and is caused by chronic HYPERTENSION in the deep leg VEINS, usually the consequences of previous deep vein thrombosis (DVT) – see THROMBOSIS; VEINS, DISEASES OF – which has destroyed the valvular system in the vein(s). The ulcer is usually preceded by chronic OEDEMA, often local eczema (see DERMATITIS), and bleeding into the skin that produces brown staining. Varicose veins may or may not be present. Control of the oedema by compression and encouragement to walk is central to management.... ulcer

Bitters are stimulants to the autonomic nervous system. They stimulate ‘bitter’ taste buds in the mouth that reflexly initiate secretion of a special hormone into the blood stream increasing production of stomach and pancreatic juices and impelling the liver to release bile into the duodenum. Bitters increase acid production and are given about half an hour before meals. To sweeten them is to nullify their effect.

Bitters increase the appetite, assist assimilation, and are indicated for perverted or loss of the sense of taste (zinc). They reduce fermentation in the intestines and are of value in hypoglycaemia and diabetes mellitus. Bitters are not carminatives. Some, such as Gentian, Calumba and Chamomile are also sialogogues (increasing the flow of saliva). Another effect, little understood, is an increase in white corpuscles in the peripheral circulation.

Aletris, Angostura, Avens, Balmony, Barberry, Betony, Bogbean, Boneset, Calumba, Centuary, Chicory, Condurango, Feverfew, Gentian, Goldenseal, Holy Thistle, Hops, Quassia Chips, Rue, Southernwood, White Horehound, Wormwood.

Not used in presence of gastric ulcer. ... bitters

compound glands of the small intestine, found in the *duodenum and the upper part of the jejunum. They are embedded in the submucosa and secrete mucus. [J. C. Brunner (1856–1927), Swiss anatomist]... brunner’s glands

n. 1. a covering or a cover-like part. The duodenal cap is the superior part of the duodenum as seen on X-ray after a barium swallow and meal. 2. (in contraception) see diaphragm.... cap

n. a form of *cholecystenterostomy in which the gall bladder is surgically anastomosed to the duodenum.... cholecystoduodenostomy

n. a protein-digesting enzyme (see peptidase). It is secreted by the pancreas in an inactive form, chymotrypsinogen, that is converted into chymotrypsin in the duodenum by the action of *trypsin.... chymotrypsin

 Storksbill. Wild Geranium. Geranium maculatum L. Herb. Dried Root. Constituents: Tannic and gallic acid.

Action: Haemostatic, astringent, anti-inflammatory, vulnerary, styptic tonic, antiseptic. A vaso- compressor to increase the vital potency of living matter of the ganglionic neurones. Anti-diarrhoea. For over-relaxed conditions.

Uses: Urinary system: frequency, incontinence in the young and aged, bed-wetting, blood in the urine. An ingredient of Captain Frank Roberts’ prescription for ulceration of stomach, duodenum and intestines. Ulceration of mouth and throat (tea used as a mouth wash and gargle). Irritable bowel. Summer diarrhoea of children.

Combines with Beth root (equal parts) as a vaginal douche for leucorrhoea or flooding of the menopause; with tincture Myrrh for cholera and infective enteritis.

Dr Wm Winder reported in the 1840s how the Indians of Great Manitoulin Island held it in high favour as a healing styptic antiseptic, “the powdered root being placed on the mouth of the bleeding vessel . . . Internally, they considered it efficacious for bleeding from the lungs”. (Virgil J. Vogel, University of Oklahoma Press, USA)

Preparations: Thrice daily.

Tea. Half-2 teaspoons dried herb to each cup boiling water; infuse 15 minutes. Half-1 cup.

Decoction. Half-1 teaspoon dried root to each cup water simmered gently 20 minutes. Half a cup.

Tablets BHP 270mg. (Gerard House)

Liquid extract: 15-30 drops.

Tincture BHP (1983). 1 part root to 5 parts 45 per cent alcohol. Dose: 2-4ml (30-60 drops).

Powdered root, as a snuff for excessive catarrh and to arrest bleeding from the nose.

Vaginal douche. 1oz root to 2 pints water simmered 20 minutes. Strain and inject. ... cranesbill, american

Old man’s beard. Snowdrop tree. Chionanthus virginicus L. German: Schneeflockenbaum. French: Chionanthe. Italian: Chionanto. Root bark. Keynote: liver.

Constituents: saponin glycoside, chionanthin.

Action: liver stimulant, cholagogue, laxative, diuretic, alterative. Tonic action on spleen and pancreas. Uses. Liver disorders, inflammation of the gall bladder and duodenum; gall stones. Jaundice, to liquefy bile and assist its elimination from the blood. Excess sugar in the urine; of value in diabetes. Suited to liverish temperaments, malaria liver, constipation, high blood pressure due to congestion of the portal circulation.

In the presence of yellow or greenish discolouration of the skin, eyes; highly coloured urine, clay- coloured stools and pain on the right side of the body: Fringe Tree is indicated.

Weil’s disease: with Echinacea BHP (1983).

Combines well with Barberry and Wild Yam (equal parts).

Preparations: Thrice daily.

Tea. 1 teaspoon to each cup water, simmer 1 minute, infuse 15 minutes: dose – half cup. Liquid extract BHP (1983) 1:1 in 25 per cent alcohol. Dose – 1-3ml.

Tincture BHP (1983) 1:5 in 45 per cent alcohol. Dose – 2-3ml.

Powder: dose – 2-4g. ... fringe tree

Schloss tea. Guimauve tea. Althaea officinalis L. German: Malve. French: Guimauve. Spanish: Malvavisco. Italian: Malvavisce. Iranian and Indian: Gul-Khairu. Chinese: K’uei. Dried peeled root.

Keynote: anti-mortification.

Constituents: mucilage, flavonoids, tannins, scopoletin.

Action. Soothing demulcent, emollient, nutrient, alterative, antilithic, antitussive, vulnerary, diuretic. Old European remedy of over 2,000 years.

Uses: Inflammation of the alimentary canal, kidneys, bladder. Ulceration of stomach and duodenum, hiatus hernia, catarrh of respiratory organs and stomach, dry cough, open wounds – to cleanse and heal, cystitis, diarrhoea, septic conditions of moderate severity. Plant supplies an abundance of mucilage for protection of mucous membranes of the mouth, nose and urinary tract in the presence of stone. A poultice or ointment is applied topically to boils, abscesses, ulcers and old wounds to draw effete matter to the surface before expulsion from the body.

Combinations. With Comfrey and Cranesbill (American) for peptic ulceration. With White Horehound, Liquorice and Coltsfoot for pulmonary disease.

Preparations: Average dose, 2-5 grams dried root. Thrice daily. For best results plant should not be boiled.

Cold decoction. Half-1 teaspoon shredded root or powder to each cup cold water; stand overnight. Dose, half-1 cup. Also used externally as a douche for inflamed eyes.

Liquid Extract BHP (1983). 1:1 in 25 per cent alcohol. Dose, 2-5ml.

Tincture. 1 part root to 5 parts alcohol (25 per cent). Dose: 5-15ml.

Traditional ‘Drawing’ ointment: Marshmallow and Slippery Elm.

Ointment (home): 5 per cent powdered root in an ointment base. See: OINTMENTS.

Poultice. Bring powdered root to the boil in milk; add a little Slippery Elm, apply. ... marshmallow

an abnormality of small blood vessels (microscopically, an arteriovenous malformation), identified predominantly in the mucosal lining of the upper stomach, that may cause severe spontaneous haemorrhage. It can rarely be found in the duodenum, colon, jejunum, or oesophagus. If detected endoscopically, curative therapy is often possible, although the abnormality is often difficult to see at gastroscopy. Surgical exploration may be required if the bleeding is unresponsive to endoscopic treatment. [G. Dieulafoy (1839–1911), French physician]... dieulafoy’s lesion

(duodeno-) combining form denoting the duodenum. Example: duodenectomy (excision of).... duoden

a condition in which there is congenital narrowing of the duodenum causing complete obstruction. It presents at birth with vomiting, which is usually bile-stained, and is associated with other congenital abnormalities, particularly *Down’s syndrome. Treatment is by restoration of any fluid and electrolyte loss followed by surgical repair.... duodenal atresia

n. a fibreoptic or video instrument for examining the interior of the duodenum. A side-viewing duodenoscope allows direct visualization of the duodenal ampulla and is used in performing *ERCP.... duodenoscope

n. an operation, now rarely performed, in which the duodenum is brought through the abdominal wall and opened, usually in order to introduce food. See also gastroduodenostomy.... duodenostomy

Procedures used to detect and follow the progress of some gastrointestinal tract disorders. Because X-rays do not pass through it, barium is used to outline organs, such as the stomach, which are not normally visible on an X-ray. In some cases, barium X-rays are an alternative to endoscopy. Barium sulphate mixed with water is passed into the part of the tract requiring examination, and X-rays are taken. X-rays may be singleor double-contrast. Single-contrast barium X-rays use barium sulphate alone. The barium fills the section of the tract and provides an outline image that shows up prominent abnormalities. In double-contrast barium X-rays, the barium forms a thin film over the inner surface of the tract, and the tract is filled with air so that small surface abnormalities can be seen.

Different types of barium X-ray examination are used to investigate different parts of the gastrointestinal tract. Barium swallow involves drinking a barium solution and is used to investigate the oesophagus. A barium meal is carried out to look at the lower oesophagus, stomach, and duodenum. Barium followthrough is used to investigate disorders of the small intestine; X-rays are taken at intervals as the barium reaches the intestine. A barium enema is used to investigate disorders of the large intestine and rectum; barium is introduced though a tube inserted in the rectum. Barium remaining in the intestine may cause constipation. Therefore, it is important to have a high-fibre diet and drink plenty of water after a barium examination, until all the barium has passed through.... barium x-ray examinations

The organs and ducts by which bile is formed, concentrated, and carried from the liver to the duodenum (the first part of the small intestine). Bile is secreted by the liver cells and collected by a network of bile ducts that carry the bile out of the liver by way of the hepatic duct. A channel called the cystic duct branches off the hepatic duct and leads to the gallbladder where bile is concentrated and stored. Beyond this junction, the hepatic duct becomes the common bile duct and opens into the duodenum at a controlled orifice called the ampulla of Vater. The presence of fat in the duodenum after a meal causes secretion of a hormone, which opens the ampulla of Vater and makes the gallbladder contract, squeezing stored bile into the duodenum.

The main disorders affecting the biliary system are gallstones, congenital biliary atresia and bile duct obstruction.

(See also gallbladder, disorders of.)... biliary system

n. a hormone from the small intestine (duodenum) that inhibits the secretion of gastric juice by the stomach. It is released when the stomach contents pass into the small intestine.... enterogastrone

a pear-shaped sac (7–10 cm long), lying underneath the right lobe of the liver, in which *bile is stored (see illustration overleaf). Bile passes (via the common hepatic duct) to the gall bladder from the liver, where it is formed, and is released into the duodenum (through the common bile duct) under the influence of the hormone *cholecystokinin, which is secreted when food is present in the duodenum. The gall bladder is a common site of stone formation (see gallstone).... gall bladder

n. a genus of small flukes, usually less than 3 mm in length, that are common as parasites of dogs and cats in the Far East, N Siberia, and the Balkan States. Adult flukes of M. yokogawai occasionally infect the human duodenum if undercooked fish (the intermediate host) is eaten. They may cause inflammation and some ulceration of the intestinal lining, which produces a mild diarrhoea. Flukes can be easily removed with tetrachloroethylene.... metagonimus

a congenital abnormality in which the pancreas develops in two parts draining separately into the duodenum, the small ventral pancreas through the main ampulla and the larger dorsal pancreas through an accessory papilla. In rare instances this is associated with recurrent abdominal pain, probably due to inadequate drainage of the dorsal pancreas. Diagnosis is made by CT imaging, magnetic resonance cholangiopancreatography (MRCP), or *ERCP.... pancreas divisum

A chronic inflammatory disease affecting the gastrointestinal tract. In young people, Crohn’s disease usually affects the ileum, causing spasms of abdominal pain, diarrhoea, loss of appetite, anaemia, weight loss, and malabsorption. In elderly people, the rectum is more often affected, causing rectal bleeding. In both groups, the disease may also affect the anus, the colon and, rarely, the mouth, oesophagus, stomach, and duodenum.

Complications include obstructions in the intestine; chronic abscesses; internal fistulas (abnormal passageways) between intestinal loops; and external fistulas from the intestine to the skin of the abdomin skin or around the anus. Complications in other parts of the body may include inflammation of the eye, severe arthritis in various joints, ankylosing spondylitis, and skin disorders (including eczema).

Investigatory procedures may include sigmoidoscopy and X-rays using barium (see barium X-ray examinations). Colonoscopy and biopsy may help distinguish the disease from ulcerative colitis.

Sulfasalazine and related drugs, and corticosteroid drugs may be prescribed.

A high-vitamin, low-fibre diet may be beneficial.

Acute attacks may require hospital treatment, and many patients need surgery.

The symptoms fluctuate over many years, eventually subsiding in some patients.

If the disease is localized, a person may remain in normal health.... crohn’s disease

The group of organs responsible for digestion. It consists of the digestive tract (also known as the alimentary tract or canal) and various associated organs. The digestive tract consists of the mouth, pharynx, oesophagus, stomach, intestines, and the anus. The intestines are the small intestine (comprising the duodenum, jejunum, and ileum) and the large intestine (comprising the caecum, colon, and rectum). The associated organs, such as the salivary glands, liver, and pancreas, secrete digestive juices that break down food as it goes through the tract.

Food and the products of digestion are moved from the throat to the rectum by peristalsis (waves of muscular contractions of the intestinal wall).

Food is broken down into simpler substances before being absorbed into the bloodstream.Physical breakdown is performed by the teeth, which cut and chew, and the stomach, which churns the food. The chemical breakdown of food is performed by the action of enzymes, acids, and salts.

Carbohydrates are broken down into simple sugars. Proteins are broken down into polypeptides, peptides, and amino acids. Fats are broken down into glycerol, glycerides, and fatty acids.

In the mouth, saliva lubricates food and contains enzymes that begin to break down carbohydrates. The tongue moulds food into balls (called boli) for easy swallowing. The food then passes into the pharynx. From here, it is pushed into the oesophagus and squeezed down into the stomach, where it is mixed with hydrochloric acid and pepsin. Produced by the stomach lining, these substances help break down proteins. When the food has been converted to a semi-liquid consistency, it passes into the duodenum where bile salts and acids (produced by the liver) help to break down fats. Digestive juices released by the pancreas into the duodenum contain enzymes that further break down food. Breakdown ends in the small intestine, carried out by enzymes produced by glands in the intestinal lining. Nutrients are absorbed in the small intestine. The residue enters the large intestine, where water is absorbed. Undigested matter is expelled via the rectum and anus as faeces.... digestive system

Faeces that differ from normal in colour, odour, consistency, or content. Abnormal faeces may indicate a disorder of the digestive system or related organ, such as the liver, but a change in the character of faeces is most often due to a change in diet.

Diarrhoea may be due simply to anxiety or may be caused by an intestinal infection (see gastroenteritis); by an intestinal disorder such as ulcerative colitis or Crohn’s disease; or by irritable bowel syndrome. Loose stools may indicate malabsorption. Constipation is generally harmless but, if it develops unexpectedly, may be caused by a large-intestine disorder such as colon cancer.

Pale faeces may be caused by diarrhoea, a lack of bile in the intestine as a result of bile duct obstruction, or a disease that causes malabsorption (such as coeliac disease). Such faeces may be oily, foul-smelling, and difficult to flush away. Dark faeces may result from taking iron tablets. However, if faeces are black, there may be bleeding in the upper digestive tract.

Faeces containing excessive mucus are sometimes associated with constipation or irritable bowel syndrome. Enteritis, dysentery, or a tumour of the intestine (see intestine, tumours of) may result in excess mucus, which is often accompanied by blood.

Blood in the faeces differs in appearance depending on the site of bleeding. Bleeding from the stomach or duodenum is usually passed in the form of black, tarry faeces. Blood from the colon is red and is usually passed at the same time as the faeces. Bleeding from the rectum or anus, which may be due to tumours or to haemorrhoids, is usually bright red. (See also rectal bleeding.)... faeces, abnormal

n. surgical removal of the pancreas. Total pancreatectomy (Whipple’s operation) involves excision of the entire gland and part of the duodenum. In subtotal pancreatectomy most of the gland is removed, usually leaving a small part close to the duodenum. In partial pancreatectomy only a portion of the gland is removed. Such operations are performed to remove tumours or tissue damaged by chronic or relapsing *pancreatitis. After total or subtotal pancreatectomy it is necessary to administer pancreatic enzymes with food to aid its digestion and insulin injections to replace that normally secreted by the gland.... pancreatectomy

the digestive juice secreted by the *pancreas. Its production is stimulated by hormones secreted by the duodenum, which in turn is stimulated by contact with food from the stomach. If the duodenum produces the hormone *secretin the pancreatic juice contains a large amount of sodium bicarbonate, which neutralizes the acidity of the stomach contents. Another hormone (see cholecystokinin) stimulates the production of a juice rich in digestive enzymes, including trypsinogen and chymotrypsinogen (which are converted to *trypsin and *chymotrypsin in the duodenum), *amylase, *lipase, and *maltase.... pancreatic juice

(pyloro-) combining form denoting the pylorus. Example: pyloroduodenal (of the pylorus and duodenum).... pylor

Examination of the stomach using a type of endoscope inserted through the mouth. Although the term specifies examination of the stomach, the oesophagus and duodenum are alsoinspected during the procedure, which is more correctly known as (see oesophagogastroduodenoscopy). Gastroscopy, in which the patient is usually sedated, is used to investigate symptoms such as bleeding from the upper gastrointestinal tract and disorders of the oesophagus, stomach, or duodenum.

Attachments to the instrument enable a biopsy to be taken and treatments such as laser treatment to be carried out.

A gastroscope may also be used to ease the passage of a gastric feeding tube through the skin (see gastrostomy).... gastroscopy

The final, longest, and narrowest section of the small intestine. It is joined at its upper end to the jejunum and at its lower end to the large intestine (comprising the caecum, colon, and rectum). The function of the ileum is to absorb nutrients from food that has been digested in the stomach and the first 2 sections of the small intestine (the duodenum and the jejunum).

Occasionally the ileum becomes obstructed, for example by pushing through a weakness in the abdominal wall (see hernia) or by becoming caught up with scar tissue following abdominal surgery

(see adhesion). Other disorders of the ileum include Meckel’s diverticulum and diseases in which absorption of nutrients is impaired, such as Crohn’s disease, coeliac disease, tropical sprue, and lymphoma.... ileum

A type of pancreatectomy in which the head of the pancreas and the loop of the duodenum are surgically removed.

whipworm infestation Small, cylindrical whip-like worms, 2.5–5 cm long, that live in the human large intestine. Infestation occurs worldwide but is most common in the tropics. Light infestation causes no symptoms; heavy infestation can cause abdominal pain, diarrhoea, and, sometimes, anaemia, since a small amount of the host’s blood is consumed every day.

Diagnosis is through the identification of whipworm eggs in the faeces. Treatment is with anthelmintic drugs, such as mebendazole. A heavy infestation may require more than 1 course of treatment. whitehead A very common type of skin blemish (see milia).... whipple’s operation

a radiological technique used to assess the anatomy and function of the upper gastrointestinal tract. The patient swallows radiopaque contrast (barium sulphate), which coats the mucosal surfaces of the oesophagus, stomach, and duodenum. The descent of the barium is charted by a series of radiographs. Gas-forming agents (such as sodium bicarbonate) may be given to aid gastric distension and improve the quality of the images. This can be used to diagnose disorders of oesophageal motor function, tumours, peptic ulcers, hiatus *hernias, and *gastro-oesophageal reflux disease. Many indications for this examination have been replaced by the use of an endoscope.... barium swallow and meal

n. an illuminated optical endoscope used to inspect the interior of the gullet (oesophagus), stomach, and duodenum. For many years these were rigid or semi-rigid instruments affording only limited views, but their modern counterparts are flexible instruments that house advanced digital systems to allow high-definition imaging of the oesophagus, stomach, and the proximal segments of the duodenum. Biopsies can be taken of visualized areas of mucosal abnormality, and therapeutic procedures (e.g. to stop a bleeding ulcer, remove a polyp, insert a *gastrostomy, dilate a stricture, or insert a self-expandable metal stent) may be performed. As the same instruments can usually be introduced into the duodenum they are also known as gastroduodenoscopes or oesophagogastroduodenoscopes. —gastroscopy n.... gastroscope

n. the act of vomiting fresh blood. The blood may have been swallowed (e.g. following a nosebleed or tonsillectomy) but more often arises from bleeding in the oesophagus, stomach, or duodenum. Common causes of upper gastrointestinal bleeding are *oesophageal varices or peptic ulcers. Vomited blood needs to be replaced by transfused blood. Gastroscopy may identify the source of bleeding and enables endoscopic treatments to arrest it. These include adrenaline injection, thermocoagulation with a *heater-probe or by *argon plasma coagulation, band ligation of oesophageal varices, glue injection for gastric varices, and the placement of metallic clips (endoclips) on bleeding vessels.... haematemesis

n. a surgical operation in which the outlet of the stomach (pylorus) is widened by a form of reconstruction. It is done to allow the contents of the stomach to pass more easily into the duodenum and is commonly combined with a truncal *vagotomy to treat peptic ulcers.... pyloroplasty

n. the lower end of the *stomach, which leads to the duodenum. It terminates at a ring of muscle – the pyloric sphincter – which contracts to close the opening by which the stomach communicates with the duodenum. —pyloric adj.... pylorus

a technique using an end-to-side anastomosis between a defunctioned section of jejunum and another upper abdominal organ (e.g. stomach, duodenum, common bile duct) in order to bypass an obstruction.... roux-en-y

n. a specialized ring of muscle that surrounds an orifice. Contractions of the sphincter partly or completely close the orifice. Sphincters are found, for example, around the anus (anal sphincter) and at the openings between the oesophagus and stomach (lower oesophageal sphincter, LOS) and between the stomach and duodenum (pyloric sphincter).... sphincter

a standard meal given to stimulate secretion of digestive juices, which can then be withdrawn by tube and measured as a test of digestive function. A fractional test meal was a gruel preparation to stimulate gastric secretion, whose acid content was measured. This has been replaced by tests using secretory stimulants. The Lundh test meal is a meal of oil and protein to stimulate pancreatic secretion, which is withdrawn from the duodenum and its trypsin content measured as a test of pancreatic function.... test meal