Small intestine (small intestine). Mucosal injury (villous cell desquamation and inflammation) Absorption of food in the small intestine

The small intestine (intestinum tenue) is the section of the digestive tract located between the stomach and the large intestine. The small intestine, together with the large intestine, forms the intestine, the longest part of the digestive system. The small intestine is divided into duodenum, jejunum, and ileum. In the small intestine, chyme (food gruel), treated with saliva and gastric juice, is exposed to the action of intestinal and pancreatic juice, as well as bile. In the lumen of the small intestine, when the chyme is stirred, its final digestion and absorption of its cleavage products take place. Remains of food move into the large intestine. The endocrine function of the small intestine is important. Endocrinocytes of its integumentary epithelium and glands produce biologically active substances (secretin, serotonin, motilin, etc.).

The small intestine begins at the level of the border of the bodies of the XII thoracic and I lumbar vertebrae, ends in the right iliac fossa, is located in the region of the womb (middle abdomen), reaching the entrance to the small pelvis. The length of the small intestine in an adult is 5-6 m. In men, the intestine is longer than in women, while in a living person the small intestine is shorter than in a corpse that lacks muscle tone. Length duodenum is 25-30 cm; about 2/3 of the length of the small intestine (2-2.5 m) is occupied by the lean intestine and approximately 2.5-3.5 m by the ileum. The diameter of the small intestine is 3-5 cm, it decreases towards the large intestine. The duodenum does not have a mesentery, unlike the jejunum and ileum, which are called the mesenteric part of the small intestine.

The jejunum (jejunum) and the ileum (ileum) make up the mesenteric part of the small intestine. Most of them are located in the umbilical region, forming 14-16 loops. Part of the loops descends into the small pelvis. The loops of the jejunum lie mainly in the upper left, and the ileum in the lower right part of the abdominal cavity. There is no strict anatomical boundary between the jejunum and the ileum. Anterior to the intestinal loops is the greater omentum, behind is the parietal peritoneum lining the right and left mesenteric sinuses. The jejunum and ileum are connected to the posterior wall of the abdominal cavity with the help of the mesentery. The root of the mesentery ends in the right iliac fossa.

The walls of the small intestine are formed by the following layers: mucous membrane with submucosa, muscular and outer membranes.

The mucous membrane (tunica mucosa) of the small intestine has circular (kerkring) folds (plicae circularis). Their total number reaches 600-700. Folds are formed with the participation of the submucosa of the intestine, their size decreases towards the large intestine. The average height of the folds is 8 mm. The presence of folds increases the surface area of ​​the mucous membrane by more than 3 times. In addition to circular folds, longitudinal folds are characteristic of the duodenum. They are found in the upper and descending parts of the duodenum. The most pronounced longitudinal fold is located on the medial wall of the descending part. In its lower section there is an elevation of the mucous membrane - major duodenal papilla(papilla duodeni major), or Vater papillae. Here, the common bile duct and the pancreatic duct open with a common opening. Above this papilla on the longitudinal fold there is minor duodenal papilla(papilla duodeni minor), where the accessory pancreatic duct opens.

The mucous membrane of the small intestine has numerous outgrowths - intestinal villi (villi intestinales), there are about 4-5 million of them. On an area of ​​​​1 mm 2 of the mucous membrane of the duodenum and jejunum, there are 22-40 villi, ileum - 18-31 villi. The average length of the villi is 0.7 mm. The size of the villi decreases towards the ileum. Allocate leaf-, tongue-, finger-like villi. The first two types are always oriented across the axis of the intestinal tube. The longest villi (about 1 mm) are predominantly leaf-shaped. At the beginning of the jejunum, the villi are usually uvula-shaped. Distally, the shape of the villi becomes finger-shaped, their length decreases to 0.5 mm. The distance between the villi is 1-3 microns. The villi are formed by loose connective tissue covered with epithelium. In the thickness of the villi there are many smooth myoitis, reticular fibers, lymphocytes, plasma cells, eosinophils. In the center of the villi is a lymphatic capillary (milky sinus), around which blood vessels (capillaries) are located.

From the surface, the intestinal villi are covered with a single layer of high cylindrical epithelium located on the basement membrane. The bulk of epitheliocytes (about 90%) are columnar epitheliocytes with a striated brush border. The border is formed by microvilli of the apical plasma membrane. On the surface of the microvilli is a glycocalyx, represented by lipoproteins and glycosaminoglycans. The main function of columnar epitheliocytes is absorption. The composition of the integumentary epithelium includes many goblet cells - unicellular glands that secrete mucus. On average, 0.5% of the cells of the integumentary epithelium are endocrine cells. In the thickness of the epithelium there are also lymphocytes penetrating from the stroma of the villi through the basement membrane.

In the gaps between the villi, intestinal glands (glandulae intestinales), or crypts, open onto the surface of the epithelium of the entire small intestine. In the duodenum there are also mucous duodenal (Brunner's) glands of complex tubular shape, located mainly in the submucosa, where they form lobules 0.5-1 mm in size. Intestinal (Lieberkuhn) glands of the small intestine have a simple tubular shape, they take place in the lamina propria of the mucous membrane. The length of the tubular glands is 0.25-0.5 mm, the diameter is 0.07 mm. On an area of ​​1 mm 2 of the mucous membrane of the small intestine, there are 80-100 intestinal glands, their walls are formed by a single layer of epitheliocytes. In total, there are more than 150 million glands (crypts) in the small intestine. Among the epithelial cells of the glands, columnar epitheliocytes with a striated border, goblet cells, intestinal endocrinocytes, borderless cylindrical (stem) cells and Paneth cells are distinguished. Stem cells are a source of regeneration of the intestinal epithelium. Endocrinocytes produce serotonin, cholecystokinin, secretin, etc. Paneth cells secrete erepsin.

The lamina propria of the small intestine mucosa is characterized by a large number of reticular fibers forming a dense network. The lamina propria always contains lymphocytes, plasma cells, eosinophils, a large number of single lymphoid nodules (in children - 3-5 thousand).

In the mesenteric part of the small intestine, especially in the ileum, there are 40-80 lymphoid, or Peyer's, plaques (noduli lymfoidei aggregati), which are clusters of single lymphoid nodules that are organs immune system. Plaques are located mainly on the antimesenteric edge of the intestine, have an oval shape.

The muscular plate of the mucous membrane (lamina muscularis mucosae) has a thickness of up to 40 microns. She distinguishes between the inner circular and the outer longitudinal layers. Separate smooth myocytes extend from the muscularis lamina into the thickness of the mucosal lamina propria and into the submucosa.

The submucosa (tela submucosa) of the small intestine is formed by loose fibrous connective tissue. In its thickness there are branches of blood and lymphatic vessels and nerves, various cellular elements. 6 submucosa of the duodenum are the secretory sections of the duodenal (brunper) glands.

The muscular membrane (tunica muscularis) of the small intestine consists of two layers. The inner layer (circular) is thicker than the outer (longitudinal) layer. The direction of myocyte bundles is not strictly circular or longitudinal, but has a spiral course. In the outer layer, the turns of the helix are more stretched than in the inner layer. Between muscle layers in loose connective tissue the nerve plexus and blood vessels are located.

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Small intestine (intestinum tenue)- an organ in which the conversion of nutrients into soluble compounds continues. Under the action of enzymes of intestinal juice, as well as pancreatic juice and bile, proteins, fats and carbohydrates are broken down, respectively, into amino acids, fatty acids and monosaccharides.

These substances, as well as salts and water, are absorbed into the blood and lymphatic vessels and carried to organs and tissues. The intestine also performs a mechanical function, pushing the chyme in the caudal direction. In addition, in the small intestine, specialized neuroendocrine (enteroendocrine) cells form some hormones (serotonin, histamine, gastrin, cholecystokinin, secretin, and others).

Small intestine represents the longest part of the digestive tube (in a living person - up to 5 m, on a corpse - 6-7 m). It starts from the pylorus of the stomach and ends with the ileocecal (ileocecal) opening at the junction of the small intestine into the large intestine. The small intestine is divided into the duodenum, jejunum, and ileum. The first short one is 25-30 cm; about 2/5 of the length of the rest of the small intestines is in the jejunum, and 3/5 is in the ileum. The width of the intestinal lumen gradually decreases from 4-6 cm in the duodenum to 2.5 cm in the ileum.

The structure of the wall of the small intestine

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The structure of the wall of the small intestine is similar in all departments. It consists of the mucous membrane, submucosa, muscular and serous membranes.

mucous membrane

The mucous membrane has a characteristic relief due to macro- and microscopic formations that are characteristic only of the small intestine. These are circular folds (more than 600), villi and crypts.

Spiral or circular folds protrude into the intestinal lumen by no more than 1 cm. The length of such folds is from half to two thirds, sometimes up to the entire circumference of the intestinal wall. When filling the intestine, the folds are not smoothed out. When moving towards the distal end of the intestine, the size of the folds decreases, and the distance between them increases. The folds are formed by the mucous membrane and submucosa (see Atl.).

Rice. 4.15. Intestinal villi and crypts of the small intestine

Rice. 4.15. Intestinal villi and crypts of the small intestine:
A - scanning microscopy;
B and C - light microscopy:
1 - villi in a longitudinal section;
2 - crypts;
3 - goblet cells;
4 - Paneth cells

The entire surface of the mucosa in the folds and between them is covered intestinal villi(Fig. 4.15; see Atl.). Their total number exceeds 4 million. These are miniature leaf-shaped or finger-shaped outgrowths of the mucous membrane, reaching a thickness of 0.1 mm, and a height of 0.2 mm (in the duodenum) to 1.5 mm (in the ileum). The number of villi is also different: from 20-40 per 1 mm 2 in the duodenum to 18-30 per 1 mm 2 - in the ileum.

Forms each villus mucous membrane; the muscular plate of the mucosa and submucosa do not penetrate into it. The surface of the villus is covered with a single layer of cylindrical epithelium. It consists of suction cells (enterocytes) - about 90% of the cells, between which goblet cells that secrete mucus and enteroendocrine cells (about 0.5% of all cells) are interspersed. An electron microscope revealed that the surface of enterocytes was covered with numerous microvilli forming a brush border. The presence of microvilli increases the suction surface of the mucous membrane of the small intestine up to 500 m 2 . The surface of the microvilli is covered with a layer of glycocalyx, which contains hydrolytic enzymes that break down carbohydrates, polypeptides, and nucleic acids. These enzymes ensure the process of parietal digestion. Cleaved substances are transported through the membrane into the cell - they are absorbed. After intracellular transformations, the absorbed substances are released into the connective tissue and penetrate into the blood and lymphatic vessels. The lateral surfaces of the epithelial cells are firmly interconnected using intercellular contacts, which prevents substances from entering the intestinal lumen into the subepithelial connective tissue. The number of scattered goblet cells gradually increases from the duodenum to the ileum. The mucus secreted by them wets the surface of the epithelium and promotes the movement of food particles.

The basis of the villus consists of loose connective tissue of its own layer of the mucous membrane with a mesh of elastic fibers, blood vessels and nerves branch out in it. In the center of the villi, a lymphatic capillary runs blindly ending at the apex, communicating with the plexus of the lymphatic capillaries of the submucosal layer. Smooth muscle cells are laid along the villus, connected by reticular fibers with the basement membrane of the epithelium and the stroma of the villus. During digestion, these cells contract, while the villi shorten, thicken, and the contents of their blood and lymph vessels are squeezed out and go into the general blood and lymph flow. When the muscle elements are relaxed, the villus straightens, swells, and the nutrients absorbed through the limbic epithelium enter the vessels. Absorption is most intense in the duodenum and jejunum.

Between the villi are tubular invaginations of the mucous membrane - crypts, or intestinal glands (Fig. 4.15; Atl.). The walls of the crypts are formed by secretory cells of various types.

At the base of each crypt are Packet cells containing large secretory granules. They contain a set of enzymes and lysozyme (a bactericidal substance). Between these cells there are small undifferentiated cells, due to the division of which the epithelium of the crypts and villi is renewed. It has been established that the renewal of intestinal epithelial cells in humans occurs every 5-6 days. Above the Packet cells are cells that secrete mucus and enteroendocrine cells.

In total, there are more than 150 million crypts in the small intestine - up to 10 thousand per 1 cm 2.

In the submucosal layer of the duodenum there are branched tubular duodenal glands that secrete a mucous secret into the intestinal crypts, which is involved in the neutralization of hydrochloric acid coming from the stomach. Some enzymes (peptidases, amylase) are also found in the secret of these glands. The greatest number of glands in the proximal parts of the intestine, then it gradually decreases, and in the distal part they disappear altogether.

There are many reticular fibers in the lamina propria of the mucous membrane, which form the "skeleton" of the villi. The muscular plate consists of an inner circular and outer longitudinal layers of smooth muscle cells. From the inner layer, individual cells extend into the connective tissue of the villi and into the submucosa. In the central part of the villus lies a blindly closed lymphatic capillary, often called the lacteal vessel, and a network of blood capillaries. The nerve fibers of the Meissner plexus are similarly located.
Throughout the small intestine, lymphoid tissue forms small single follicles in the mucous membrane, up to 1–3 mm in diameter. In addition, in the distal ileum, on the side opposite to the attachment of the mesentery, there are groups of nodules that form follicular plaques (Peyer's patches) (Fig. 4.16; Atl.).

Rice. 4.16. The structure of the small intestine:
1 - muscular membrane;
2 - mesentery;
3 - serous membrane;
4 - single follicles;
5 - circular folds;
6 - mucous membrane;
7 - follicular plaque

These are flat, elongated plates along the intestine, reaching several centimeters in length and 1 cm in width. Follicles and plaques, like lymphoid tissue in general, play a protective role. In children from 3 to 15 years old, there are about 15,000 single lymph nodes. In old age, their number decreases. The number of plaques also decreases with age from 100 in children to 30-40 in adults, they are almost never found in the elderly. In the area of ​​the plaques, intestinal villi are usually absent.

submucosa

In the submucosa, accumulations of fat cells are often found. The vascular and nervous plexuses are located here, and the secretory sections of the glands lie in the duodenum.

Muscular membrane

The muscular membrane of the small intestine is formed by two layers of muscle tissue: inner, more powerful, circular and outer - longitudinal. Between these layers lies the intermuscular nerve plexus, which regulates the contractions of the intestinal wall.

The motor activity of the small intestine is represented by peristaltic, undulating movements, and rhythmic segmentation (Fig. 4.17).

They arise due to the contraction of the circular muscles, spread through the intestine from the stomach to the anus and lead to the promotion and mixing of the chyme. Areas of contraction alternate with areas of relaxation. The frequency of contractions decreases in the direction from the upper intestine (12/min) to the lower (8/min). These movements are regulated by the autonomic nervous system and hormones, most of which are formed in the gastrointestinal tract itself. sympathetic nervous system inhibits the motor activity of the small intestine, and parasympathetic enhances it. Bowel movements persist after the destruction of the vagus and sympathetic nerves, but the strength of contractions decreases, which indicates the dependence of these contractions on innervation; this is also true for peristalsis. Segmentation is associated with intestinal smooth muscle, which can respond to local mechanical and chemical stimuli. One of these chemicals is serotonin, which is produced in the intestines and stimulates its movement. Thus, the contractions of the small intestine are regulated by external neural connections, the activity of the smooth muscle itself, and local chemical and mechanical factors.

In the absence of food intake, peristaltic movements predominate, contributing to the promotion of chyme. Eating slows them down - movements associated with mixing the contents of the intestine begin to predominate. The duration and intensity of motility depends on the composition and calorie content of food and decreases in the series: fats - proteins - carbohydrates.

Serous membrane

The serous membrane covers the small intestine from all sides, with the exception of the duodenum, which is covered by the peritoneum only in front.

Duodenum

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Duodenum (duodenum) has a horseshoe shape (see Atl.). The initial segment of the intestine is covered with peritoneum on three sides, i.e. located intraperitoneally. The remaining large part is attached to the posterior abdominal wall and is covered by the peritoneum only in front. The remaining walls of the intestine have a connective tissue (adventitial) membrane.

In the intestine, the upper part is distinguished, starting from the pylorus of the stomach and lying at the level of the 1st lumbar vertebra, descending, which descends to the right along the spine to the level of the 3rd lumbar vertebra, and the lower, passing after a slight bend upwards, at the level of the 2nd lumbar vertebra, into the jejunum. The upper part lies under the liver, in front of the lumbar part of the diaphragm, the descending part is adjacent to the right kidney, is located behind the gallbladder and the transverse colon, and the lower part lies near the aorta and the inferior vena cava, in front of it it crosses the root of the mesentery of the jejunum.

The head of the pancreas is located in the flexure of the duodenum. The excretory duct of the latter, together with the common bile duct, obliquely penetrates the wall of the descending part of the intestine and opens at the elevation of the mucous membrane, which is called the major papilla. Very often, a small papilla protrudes 2 cm above the major papilla, on which the accessory pancreatic duct opens.

The duodenum is connected by ligaments to the liver, kidneys, and transverse colon. The hepatoduodenal ligament contains the common bile duct, portal vein, hepatic artery, and lymphatic vessels of the liver. In the remaining ligaments, arteries pass, supplying the stomach and mesentery.

Skinny and ileum

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Skinny (jejunum) and ileum (ileum) intestines (see Atl.) are covered on all sides with a serous membrane (peritoneum) and are movably suspended from the back wall of the abdomen on the mesentery. They form many loops, which in a living person, due to peristaltic contractions, constantly change their shape and position, filling most of the peritoneal cavity.

There is no anatomical boundary between the jejunum and ileum; the loops of the first lie predominantly in the left side of the abdomen, and the loops of the second occupy its middle and right parts. The greater omentum lies in front of the small intestine. In the right lower part of the abdomen (in the ileum), the ileum opens into the initial part of the colon. The mesentery leads to the intestines with blood vessels and nerves.

Blood supply to the small intestine

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The small intestine is supplied with blood through the mesenteric arteries and the hepatic artery (duodenum). The small intestine is innervated by the plexuses of the autonomic nervous system of the abdominal cavity and the vagus nerve.

The human small intestine is part of the digestive tract. This department is responsible for the final processing of substrates and absorption (suction).

What is the small intestine?

The human small intestine is a narrow tube about six meters long.

This section of the digestive tract got its name because of the proportional features - the diameter and width of the small intestine is much smaller than those of the large intestine.

The small intestine is divided into the duodenum, jejunum and ileum. The duodenum is the first segment of the small intestine, located between the stomach and the jejunum.

Here the most active processes of digestion take place, it is here that pancreatic and gallbladder enzymes are secreted. The jejunum follows the duodenum, its average length is one and a half meters. Anatomically, the jejunum and ileum are not separated.

The mucous membrane of the jejunum on the inner surface is covered with microvilli that absorb nutrients, carbohydrates, amino acids, sugar, fatty acids, electrolytes and water. The surface of the jejunum increases due to special fields and folds.

Vitamin B12 and other water-soluble vitamins are absorbed in the ileum. In addition, this area of ​​the small intestine is also involved in the absorption nutrients. The functions of the small intestine are somewhat different from those of the stomach. In the stomach, food is crushed, ground and primarily decomposed.

Substrates are broken down in the small intestine constituent parts and absorbed for transport to all parts of the body.

Anatomy of the small intestine

As we noted above, in the digestive tract, the small intestine immediately follows the stomach. The duodenum is the initial section of the small intestine, following the pyloric section of the stomach.

The duodenum begins at the bulb, bypasses the head of the pancreas, and ends in the abdominal cavity with the ligament of Treitz.

The peritoneal cavity is a thin connective tissue surface that covers some of the abdominal organs.

The rest of the small intestine is literally suspended in the abdominal cavity by a mesentery attached to the posterior abdominal wall. This structure allows you to freely move the sections of the small intestine during surgery.

The jejunum occupies the left side of the abdominal cavity, while the ileum is located in the upper right side of the abdominal cavity. The inner surface of the small intestine contains mucous folds called circular circles. Such anatomical formations are more numerous in the initial section of the small intestine and are reduced closer to the distal ileum.

The assimilation of food substrates is carried out with the help of primary cells of the epithelial layer. Cubic cells located throughout the entire area of ​​the mucous membrane secrete mucus that protects the intestinal walls from an aggressive environment.

Enteric endocrine cells secrete hormones into the blood vessels. These hormones are essential for digestion. The squamous cells of the epithelial layer secrete lysozyme, an enzyme that destroys bacteria. The walls of the small intestine are closely connected with the capillary networks of the circulatory and lymphatic systems.

The walls of the small intestine are composed of four layers: mucosa, submucosa, muscularis, and adventitia.

functional significance

The human small intestine is functionally connected with all organs of the gastrointestinal tract, digestion of 90% of food substrates ends here, the remaining 10% are absorbed in the large intestine.

The main function of the small intestine is to absorb nutrients and minerals from food. The digestion process has two main parts.

The first part involves the mechanical processing of food by chewing, grinding, whipping and mixing - all this takes place in oral cavity and stomach. The second part of food digestion involves the chemical processing of substrates, which uses enzymes, bile acids, and other substances.

All this is necessary in order to decompose whole products into individual components and absorb them. Chemical digestion occurs in the small intestine - it is here that the most active enzymes and excipients are present.

Ensuring digestion

After rough processing of products in the stomach, it is necessary to decompose the substrates into separate components available for absorption.

1. The breakdown of proteins. Proteins, peptides and amino acids are affected by special enzymes, including trypsin, chymotrypsin and intestinal wall enzymes. These substances break down proteins into small peptides. Protein digestion begins in the stomach and ends in the small intestine.
2. Digestion of fats. This purpose is served by special enzymes (lipases) secreted by the pancreas. Enzymes break down triglycerides into free fatty acids and monoglycerides. An auxiliary function is provided by bile juices secreted by the liver and gallbladder. Bile juices emulsify fats - they separate them into small drops available for the action of enzymes.
3. Digestion of carbohydrates. Carbohydrates are classified into simple sugars, disaccharides and polysaccharides. The body needs the main monosaccharide - glucose. Pancreatic enzymes act on polysaccharides and disaccharides, which promote the decomposition of substances to monosaccharides. Some carbohydrates are not completely absorbed in the small intestine and end up in colon where they become food for intestinal bacteria.

Absorption of food in the small intestine

Decomposed into small components, nutrients are absorbed by the mucous membrane of the small intestine and move into the blood and lymph of the body.

Absorption is provided by special transport systems of digestive cells - each type of substrate is provided with a separate method of absorption.

The small intestine has a significant internal surface area, which is essential for absorption. Circular circles of the intestine contain a large number of villi that actively absorb food substrates. Modes of transport in the small intestine:

• Fats undergo passive or simple diffusion.
• Fatty acids are absorbed by diffusion.
• Amino acids enter the intestinal wall by active transport.
• Glucose enters through secondary active transport.
• Fructose is absorbed by facilitated diffusion.

For a better understanding of the processes, it is necessary to clarify the terminology. Diffusion is a process of absorption along the concentration gradient of substances, it does not require energy. All other types of transport require the expenditure of cellular energy. We found out that the human small intestine is the main section of food digestion in the digestive tract.

Watch the video about the anatomy of the small intestine:

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Causes and treatment of increased gas formation in adults

Flatulence is called excessive gas formation in the intestines. As a result, digestion is difficult and disrupted, nutrients are poorly absorbed, and the production of enzymes necessary for the body is reduced. Flatulence in adults is eliminated with the help of drugs, folk remedies and diets.

1. Causes of flatulence
2. Diseases that provoke flatulence
3. Flatulence during pregnancy
4. The course of the disease
5. Flatulence treatment
6. Medicines
7. Folk recipes
8. Power correction
9. Conclusion

Causes of flatulence

The most common cause of flatulence is malnutrition. An excess of gases can occur in both men and women. This condition is often provoked by foods that are high in fiber and starch. As soon as they accumulate more than the norm, the rapid development of flatulence begins. The cause is also carbonated drinks and products from which a fermentation reaction occurs (lamb, cabbage, legumes, etc.).

Often, increased flatulence appears due to a violation of the enzyme system. If they are not enough, then a lot of undigested food penetrates into the terminal sections of the gastrointestinal tract. As a result, it begins to rot, fermentation processes are activated with the release of gases. An unhealthy diet leads to a lack of enzymes.

A common cause of flatulence is a violation of the normal microflora of the large intestine. With its stable operation, part of the resulting gases is destroyed by special bacteria, for which this is a source of vital activity. However, when they are overproduced by other microorganisms, the balance in the intestine is disturbed. Gas causes an unpleasant smell of rotten eggs during bowel movements.

The cause of flatulence can also be:

1. Stress, causing muscle spasms and slowing down of the intestines. At the same time, sleep is disturbed. Most often, the disease occurs in women.
2. Surgical operations, after which the activity of the gastrointestinal tract decreases. The progress of the food mass slows down, which provokes the processes of fermentation and decay.
3. Adhesions and tumors. They also interfere with the normal movement of food masses.
4. Milk intolerance causes gas buildup.

Morning flatulence can be caused by a lack of fluid in the body. In this case, the bacteria begin to intensively release gases. Only pure water helps to reduce them. Eating at night also contributes to increased gas formation. The stomach does not have time to rest, and part of the food is undigested. Fermentation appears in the intestines.

In addition to these reasons, there is "senile flatulence of the intestine." Often, gases accumulate during sleep. Their excessive increase appears against the background of age-related changes in the body, due to lengthening of the intestine, atrophy of the muscular wall of the organ, or a decrease in the number of glands that are involved in the release of digestive enzymes. With gastritis, gases often accumulate during sleep.

Diseases that provoke flatulence

Increased gas formation can be caused by a number of diseases:

1. With duodenitis, the duodenum becomes inflamed and the synthesis of digestive enzymes is disrupted. As a result, rotting and fermentation of undigested food begins in the intestines.
2. With cholecystitis during the inflammatory process, the outflow of bile is disturbed. Since it does not enter the duodenum sufficiently, the organ begins to function incorrectly.
3. With gastritis in the gastrointestinal tract, the level of acidity changes and proteins are broken down very slowly. This disrupts the peristalsis of the intestines of the digestive tract.
4. With pancreatitis, the pancreas is deformed and swells. Healthy tissues are replaced by fibrous ones, in which there are almost no living cells. Due to structural changes, the production of digestive enzymes is reduced. There is a deficiency of pancreatic juice, and as a result, the digestion of food is disturbed. Because of this, gas emission is greatly increased.
5. With enteritis, the mucosa of the small intestine is deformed. As a result, the absorption of food and its processing are disturbed.
6. The same thing happens during colitis. The balance of the intestinal microflora is disturbed. These changes lead to increased gas formation.
7. In cirrhosis, the liver cannot secrete bile properly. As a result, fats are not fully digested. Increased gas formation usually occurs after fatty foods.
8. During acute intestinal infections, the pathogen most often enters through the mouth with contaminated food or water. After that, harmful microorganisms begin to multiply rapidly and release toxins (toxic substances). They have a negative effect on the muscles of the intestine. Because of this, the removal of gases from the body is disrupted, and they begin to accumulate. There is severe bloating.
9. With obstruction of the gastrointestinal tract, its peristalsis is disturbed due to a mechanical obstacle (helminths, neoplasms, foreign bodies, etc.).
10. With irritable bowel syndrome, the sensitivity of the receptors of its walls changes. This disrupts the motility of the organ, mainly the colon, absorption and secretion. As a result, pronounced flatulence appears.
11. With intestinal atony, the rate of movement of feces and chyme is significantly reduced, which causes the accumulation of gases.
12. With diverticulitis of the intestine, the level of pressure in it is disturbed. Its increase leads to lesions of the muscle layer, defects appear. False diverticulitis is formed and severe flatulence appears.
13. With neurosis, the nervous system is overexcited. As a result, intestinal peristalsis is disturbed.

Flatulence during pregnancy

In women during pregnancy, flatulence occurs for a number of reasons:

• intestinal compression;
• hormonal changes in the body;
• stress;
• violation of the microflora in the intestine;
• malnutrition;
• diseases of the gastrointestinal tract.

Treatment of flatulence during pregnancy is carried out strictly according to the doctor's recommendations. During this period, women should not take many medicines, and folk methods not all will fit. A pregnant woman should:

• follow a diet;
• chew food thoroughly;
• exclude carbonated drinks from the diet.

At the same time, a woman needs to be active and wear loose clothing. Flatulence cannot be treated on its own. Medicines should be prescribed only by a doctor. Without his consultation, you can use activated charcoal. It absorbs all toxins and harmful substances. Linex has the same effect.

The course of the disease

The course of the disease is divided into two types:

1. The first is when flatulence manifests itself after an increase in the abdomen due to the accumulation of gases. Their discharge is very difficult due to intestinal spasm. This is accompanied by pain in the abdomen and a feeling of fullness.
2. In another variant, gases, on the contrary, intensively exit the intestines. Moreover, this process becomes regular. This phenomenon causes pain in the intestines. But even those around the patient can hear loudly how his stomach rumbles and boils due to the transfusion of the contents.

Flatulence treatment

Medicines

Therapy begins with the elimination of concomitant diseases that provoke strong gas formation.

• Pre- and probiotic preparations are prescribed (Biobacton, Acylact, etc.). Antispasmodics help reduce pain (Papaverine, No-Shpa, etc.).
• To eliminate sudden gas formation, enterosorbents are used (activated carbon, Smecta, Enterosgel and others).
• Drugs are also prescribed that eliminate increased gas formation. Adsobents (activated carbon, Polysorb, etc.) and defoamers (Espumizan, Disflatil, Maalox plus, etc.) are prescribed.
• Flatulence is also treated with enzymatic preparations (Pancreatin, Mezim Forte, etc.).
• When vomiting, Metoclopramide or Cerucal is prescribed.

When flatulence appears for the first time, Espumizan can be used to quickly eliminate symptoms. It belongs to defoaming drugs and collapses gas bubbles immediately in the intestine. As a result, heaviness in the abdomen and pain quickly disappear. Mezim Forte and activated charcoal help to eliminate the same symptoms in a short time.

Folk recipes

Folk remedies for bloating and excessive gas formation:

1. Dill seeds (1 tablespoon) are poured with a glass of boiling water. Infuse until completely cooled. The remedy is filtered and drunk in the morning.
2. Crushed carrot seeds. They need to drink 1 tsp. per day for bloating.
3. A decoction is prepared from dandelion roots. Crushed and dried plant in the amount of 2 tbsp. l. pour 500 ml of boiling water. After the product has cooled, it is filtered. The decoction is divided into 4 parts and gradually drunk during the day.
4. Ginger root is crushed and dried. The powder is consumed in a quarter of a teaspoon per day, after which it is washed down with plain water.
5. An infusion is made from St. John's wort, yarrow and marsh cudweed. All plants are taken in crushed dried form, 3 tbsp. l. The infusion is taken to reduce gas formation.

Increased gas formation can be cured within a day. For this, parsley root (1 tsp) is infused for 20 minutes in a glass cold water. Then the mixture is slightly warmed up and drunk every hour in a big gulp until the liquid in the glass runs out.

An infusion of dried thyme and dill seeds helps to quickly get rid of flatulence. They are taken in 1 tsp. and pour 250 ml of boiling water. The product is infused for 10 minutes under a tightly closed lid. From above it is covered with a towel, then filtered. Infusion should be drunk every hour for 30 ml. The last dose should be before dinner.

Power correction

Treatment for flatulence includes diet. It is an auxiliary, but mandatory addition. Flatulence during sleep is often caused by food eaten for dinner.

1. All foods with coarse fiber are removed from the diet.
2. You can not eat legumes, cabbage and other foods that cause fermentation in the intestines.
3. If lactose intolerance is observed, the amount of milk sugar and calories in the diet is reduced.
4. Meat and fish should be lean, steamed or boiled. Bread is eaten dried or stale.
5. Of vegetables, carrots, beets, cucumbers, tomatoes and spinach are allowed.
6. You can eat fat-free yogurt and cottage cheese.
7. Porridges are prepared only from brown rice, buckwheat or oatmeal.
8. It is necessary to abandon fried foods, smoked meats and pickles.
9. Do not drink carbonated and alcoholic drinks.
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According to morphofunctional features, the intestines are divided into thin and thick sections.

Small intestine(intestinum tenue) is located between the stomach and the caecum. The length of the small intestine is 4-5 m, the diameter is about 5 cm. There are three sections: the duodenum, jejunum and ileum. In the small intestine, all kinds of nutrients - proteins, fats and carbohydrates - undergo chemical processing. The enzymes enterokinase, kinasogen and trypsin, which break down simple proteins, are involved in the digestion of proteins; erepsin, which breaks down peptides into amino acids, nuclease digests complex nucleoprotein proteins. Carbohydrates are digested by amylase, maltase, sucrase, lactase and phosphatase, while fats are digested by lipase. In the small intestine, the process of absorption of the breakdown products of proteins, fats and carbohydrates into the blood and lymphatic vessels takes place. The intestine performs a mechanical (evacuation) function - it pushes food particles (chyme) towards the large intestine. The small intestine is also characterized by an endocrine function performed by special secretory cells and consists in the production of biologically active substances - serotonin, histamine, motilin, secretin, enteroglucogon, cholecystokinin, pancreozymin, gastrin.

The wall of the small intestine consists of four membranes: mucous (tunica mucosa), submucosa (tunica submcosa), muscular (tunica muscularis), serous (tunica serosa).

mucous membrane represented by epithelium (single-layered cylindrical border), lamina propria (loose fibrous connective tissue), muscular lamina (smooth muscle cells). A feature of the relief of the mucous membrane of the small intestine is the presence of circular folds, villi and crypts.

Circular folds composed of mucosa and submucosa.

intestinal villus- this is a finger-shaped outgrowth of the mucous membrane 5-1.5 mm high, directed into the lumen of the small intestine. The villus is based on the connective tissue of the lamina propria, in which there are separate smooth myocytes. The surface of the villus is covered with a single layer of cylindrical epithelium, in which three types of cells are distinguished: columnar epitheliocytes, goblet cells and intestinal endocrinocytes.

Columnar epithelial cells of the villi(lepitheliocyti columnares) make up the bulk of the epithelial layer of the villus. These are tall cylindrical cells measuring 25 µm. On the apical surface, they have microvilli, which under a light microscope look like a striated border. The microvilli are about 1 µm high and 0.1 µm in diameter. The presence of villi in the small intestine, as well as microvilli of columnar cells, the absorptive surface of the mucous membrane of the small intestine increases tenfold. Columnar epithelial cells have an oval nucleus, a well-developed endoplasmic reticulum, and lysosomes. The apical part of the cell contains tonofilaments (terminal layer), with the participation of which the end plates and tight junctions are formed, which are impermeable to substances from the lumen of the small intestine.

Columnar epithelial cells of the villi are the main functional element of the processes of digestion and absorption in the small intestine. The microvilli of these cells adsorb enzymes on their surface and break down nutrients with them. This process is called parietal digestion, unlike abdominal and intracellular, occurring in the lumen of the intestinal tube. On the surface of the microvilli is a glycocalyx, represented by lipoproteins and glycosaminoglycans. The breakdown products of proteins and carbohydrates - amino acids and monosaccharides - are transported from the apical surface of the cell to the basal one, from where they enter the capillaries of the connective tissue base of the villi through the basal membrane. This way of absorption is also characteristic of water, mineral salts and vitamins dissolved in it. Fats are absorbed either by phagocytosis of emulsified fat droplets by columnar epithelial cells, or by absorption of glycerol and fatty acids, followed by resynthesis of neutral fat in the cytoplasm of the cell. Lipids through the basal surface of the plasmolemma of columnar epithelial cells enter the lymphatic capillaries.

goblet exocrinocytes(exocrinocyti caliciformes) are unicellular glands that produce a mucous secretion. In the expanded apical part, the cell accumulates a secret, and in the narrowed basal part, the nucleus, the endoplasmic reticulum, and the Goldki apparatus are located. Goblet cells are located on the surface of the villi singly, surrounded by columnar epitheliocytes. The secret of goblet cells serves to moisten the surface of the intestinal mucosa and thus promote the movement of food particles.

endocrinocytes(endocrinocyti dastrointestinales) are scattered singly among columnar epithelial cells with a border. Among the endocrinocytes of the small intestine, there are EC-, A-, S-, I-, G-, D-cells. The products of their synthetic activity are a number of biologically active substances that have a local effect on the secretion, absorption and motility of the intestine.

Intestinal crypts- these are tubular recesses of the epithelium in the own plate of the intestinal mucosa. The entrance to the crypt opens between the bases of neighboring villi. The depth of the crypts is 0.3-0.5 mm, the diameter is about 0.07 mm. There are about 150 million crypts in the small intestine, together with the villi they significantly increase the functionally active area of ​​the small intestine. Among the epithelial cells of the crypts, in addition to columnar cells with a border, goblet cells and endocrinocytes, there are also columnar epitheliocytes without a border and exocrinocytes with acidophilic granularity (Paneth cells).

Exocrinocytes with acidophilic granules or Paneth cells (endocrinocyti cumgranulis acidophilis) are located in groups near the bottom of the crypts. Cells of a prismatic shape, in the apical part of which there are large acidophilic secretory granules. The nucleus, endoplasmic reticulum, Golgi complex are displaced to the basal part of the cell. The cytoplasm of Paneth cells stains basophilically. Paneth cells secrete dipeptidases (erepsin), which break down dipeptides into amino acids, and also produce enzymes that neutralize hydrochloric acid, which enters the small intestine with food particles.

Columnar epitheliocytes borderless or undifferentiated epitheliocytes (endocrinocyti nondilferentitati) are poorly differentiated cells that are the source of physiological regeneration of the epithelium of the crypts and villi of the small intestine. In structure, they resemble border cells, but their apical surface lacks microvilli.

own record The mucous membrane of the small intestine is formed mainly by loose fibrous connective tissue, where elements of the reticular connective tissue occur. In the lamina propria, accumulations of lymphocytes form single (solitary) follicles, as well as grouped lymphoid follicles. Large accumulations of follicles penetrate through the muscular plate of the mucous membrane into the submucosa of the intestine.

muscularis lamina The mucous membrane is formed by two layers of smooth myocytes - inner circular and outer longitudinal.

Submucosa The walls of the small intestine are formed by loose fibrous connective tissue, in which there are a large number of blood and lymphatic vessels, and nerve plexuses. In the duodenum in the submucosa are the terminal secretory sections of the duodenal (Bruner's) glands. By structure, these are complex branched tubular glands with a mucous-protein secret. The terminal sections of the glands are composed of mucocytes, Paneth cells, and endocrinocytes (S-cells). The excretory ducts open into the intestinal lumen at the base of the crypts or between adjacent villi. The excretory ducts are built by cubic-shaped mucocytes, which at the surface of the mucous membrane are replaced by columnar cells with a border. The secret of the duodenal glands protects the duodenal mucosa from the harmful effects of gastric juice. Dipeptidases - products of the duodenal glands - break down dipeptides to amino acids, amylase breaks down carbohydrates. In addition, the secret of the duodenal glands is involved in the neutralization of acidic compounds of gastric juice.

Muscular membrane The small intestine is formed by two layers of smooth myocytes: internal oblique circular and external oblique longitudinal. Between them lie layers of loose fibrous connective tissue, rich in neurovascular plexuses. Function of the muscular membrane: mixing and promotion of digestion products (chyme).

Serous membrane The small intestine is formed by loose fibrous connective tissue, which is covered with mesothelium. It covers the outside of the small intestine from all sides, with the exception of the duodenum, which is covered by the peritoneum only in front, and in other parts has a connective tissue membrane.

Colon(intestinum crassum) a section of the digestive tube that provides the formation and conduction of feces. Metabolic products, salts of heavy metals and others are released into the lumen of the colon. The bacterial flora of the large intestine produces vitamins B and K, and also ensures the digestion of fiber.

Anatomically, the large intestine is divided into the following sections: caecum, appendix, colon (its ascending, transverse and descending sections), sigmoid and rectum. The length of the large intestine is 1.2-1.5 m, the diameter is 10 mm. Four membranes are distinguished in the wall of the large intestine: mucous, submucosal, muscular and external - serous or adventitious.

mucous membrane The large intestine is formed by a single layer of prismatic epithelium, a connective tissue lamina propria, and a muscular lamina. The relief of the mucous membrane of the colon is determined by the presence of a large number of circular folds, crypts and the absence of villi. Circular folds are formed on the inner surface of the intestine from the mucous membrane and submucosa. They are located across and have a crescent shape. Most of the epithelial cells of the large intestine are represented by goblet cells, there are fewer columnar cells with a striated border and endocrinocytes. At the base of the crypts are undifferentiated cells. These cells do not differ significantly from similar cells of the small intestine. Mucus covers the epithelium and promotes the sliding and formation of feces.

In the lamina propria of the mucous membrane there are significant accumulations of lymphocytes that form large single lymphatic follicles that can penetrate the muscular lamina of the mucous membrane and merge with similar formations of the submucosa. Accumulations of dissociated lymphocytes and lymphatic follicles in the wall of the digestive tube are considered an analogue of the bursa (bag) of Fabricius of birds, responsible for the maturation and acquisition of immune competence by B-lymphocytes.

There are especially many lymphatic follicles in the wall of the appendix. The epithelium of the mucous membrane of the appendix is ​​a single-layer prismatic, infiltrated by lymphocytes, with a small content of goblet cells. It contains Paneth cells and intestinal endocrinocytes. In the endocrinocytes of the appendix, the main part of the serotonin and melatonin of the body is synthesized. The lamina propria without a sharp border (due to the weak development of the muscular mucosal lamina) passes into the submucosa. In the lamina propria and in the submucosa there are numerous large locally confluent accumulations of lymphoid tissue. The appendix performs a protective function, accumulations of the lymphoid are part of peripheral departments immune system tissue in it

The muscular plate of the mucous membrane of the large intestine is formed by two layers of smooth myocytes: internal circular and external oblique-longitudinal.

submucosa The large intestine is formed by loose fibrous connective tissue, in which there are accumulations of fat cells, as well as a significant number of lymphatic follicles. In the submucosa are the neurovascular plexus.

The muscular coat of the large intestine is formed by two layers of smooth myocytes: inner circular and outer longitudinal, between them are layers of loose fibrous connective tissue. In the colon, the outer layer of smooth myocytes is not continuous, but forms three longitudinal bands. The shortening of individual segments of the inner layer of smooth myocytes of the muscular membrane contributes to the formation of transverse folds of the colon wall.

The outer shell of most of the large intestine is serous, adventitial in the caudal part of the rectum.

Rectum- has a number of structural features. It distinguishes between the upper (pelvic) and lower (anal) parts, which are separated from each other by transverse folds.

The mucous membrane of the upper part of the rectum is covered with a single layer of cubic epithelium, which forms deep crypts.

The mucous membrane of the anal part of the rectum is formed by three zones of different structure: columnar, intermediate and skin.

The columnar zone is covered with stratified cuboidal epithelium, the intermediate zone is covered with stratified squamous non-keratinized epithelium, and the cutaneous zone is covered with stratified squamous keratinized epithelium.

The lamina propria of the columnar zone forms 10-12 longitudinal folds, contains blood lacunae, single lymphatic follicles, rudiments: rudimentary anal glands. The lamina propria of the intermediate and zone is rich in elastic fibers, sebaceous jelly is located here, and there are dissociated lymphocytes. Hair follicles, terminal sections of apocrine sweat glands, and sebaceous glands appear in the lamina propria of the rectum in its skin part.

The muscular plate of the mucous membrane of the rectum is formed by the inner circular and outer longitudinal layers of smooth myocytes.

The submucosa of the rectum is formed by loose fibrous connective tissue, in which the nerve and vascular plexuses are located.

The muscular layer of the rectum is formed by the inner circular outer longitudinal layers of smooth myocytes. The muscular membrane forms two sphincters, which play an important role in the act of defecation. The internal sphincter of the rectum is formed by a thickening of smooth myocytes of the inner layer of the muscular membrane, the outer - by bundles of fibers of striated muscle tissue.

The upper part of the rectum is covered on the outside with a serous membrane, the anal part is covered with an adventitious membrane.

Cancer of the small intestine is a malignant neoplasm that originates from the cells of one's own intestinal tissue.

Tumors of the small intestine are rare and account for 1% of all intestinal cancers. The length of the loop-shaped small intestine reaches 4.5 m. It consists of the intestines: duodenum, jejunum and ileum. In each of these components, under favorable conditions, small intestine cancer can degenerate from a normal cell.

Malignant tumor of the small intestine

The absence of obvious specific primary symptoms forces patients to seek medical help in the later stages of the disease. At the same time, metastasis begins, due to which secondary intestinal cancer develops.

Metastases reach regional lymph nodes and other distant parts of the intestine, so the following oncological diseases can develop:

Causes of small intestine cancer

No specific direct cause of oncology of the small intestine has yet been found. Attention is always drawn to chronic enzymatic or inflammatory bowel disease, cancer symptoms can hide behind signs of disease, such as diverticulitis, ulcerative colitis, enteritis, Crohn's disease, duodenal ulcer. Often, the tumor develops against the background of adenomatous polyps, prone to degeneration into oncogenic ones.

The duodenum is often affected due to the irritating effect of bile. The initial part of the small intestine is due to pancreatic juice and active contact with carcinogens from food, fried foods, alcohol and nicotine.

The first symptoms and signs of small intestine cancer in men and women

If duodenal cancer is suspected, the first symptoms will be similar to peptic ulcer stomach and duodenum and will manifest as an aversion to food, dull pain in the epigastric zone with irradiation to the back. Late stage duodenal cancer exhibits symptoms associated with poor patency biliary tract and intestines due to tumor growth. The patient will suffer from endless nausea and vomiting, flatulence and manifestations of jaundice.

The jejunum and ileum signals oncology with the first local signs and general dyspeptic disorders:

• nausea and vomiting;
• bloating;
• pain in the intestines;
• spasms in the navel and / or epigastric region;
• frequent liquid stool with slime.

It has been proven that symptoms and manifestations of small intestine cancer in men occur more often than in women. This fact is associated with the way of life of men, nutrition and abuse of malicious habits: alcohol, smoking and drugs. In addition, small intestine cancer develops, signs and symptoms appear somewhat differently due to different structure urinary system.

Very often, with cancer of the breast and cervix, ovaries, there are signs of bowel cancer in women. With metastases of a tumor of the prostate gland, testicles, symptoms of intestinal cancer in men may appear. If the tumor compresses neighboring organs, then this leads to the development of pancreatitis, jaundice, ascites, intestinal ischemia.

Small intestine cancer: symptoms and manifestations

The tumor grows, so the symptoms of oncology in the small intestine increase:

• intestinal patency is disturbed;
• there is a clear or hidden intestinal blood loss;
• perforation of the intestinal wall develops;
• the contents enter the peritoneal cavity and peritonitis begins;
• intoxication (poisoning) of the body increases due to the decay of tumor cells, ulcers and intestinal fistulas appear;
• iron deficiency increases;
• impaired function of the pancreas and liver.

Cancer has no gender, so the symptoms of bowel cancer in women and men are mostly the same: increasing weakness, weight loss, malaise, anemia and rapid and inexplicable fatigue, nervousness, anorexia, difficulty with bowel movements accompanied by pain, itching , frequent calls.

Classification of stages of cancer of the small intestine. Types and types of small intestine cancer

According to the histological classification, oncological formations of the small intestine are:

• adenocarcinoma- develops from glandular tissue near the large papilla of the duodenum. The tumor is ulcerated and covered with a fleecy surface;
• carcinoid- develops in any part of the intestine, more often - in the appendix. Less often - in the ileum, very rarely - in the rectum. The structure is similar to the epithelial form of cancer.
• lymphoma- rare oncological formation (18%) and combines lymphosarcoma and lymphogranulomatosis (Hodgkin's disease);
• leiomyosarcoma- a large oncological formation, more than 5 cm in diameter, can be palpated through the wall of the peritoneum. The tumor creates intestinal obstruction, perforation of the wall.

Lymphoma of the small intestine can be primary or secondary. If primary lymphoma of the small intestine is confirmed, the symptoms are characterized by the absence of hepatosplenomegaly, enlarged lymph nodes, changes on the chest x-ray, CT, in the blood and bone marrow. If the tumor is large, there will be disturbances in the absorption of food.

If the retroperitoneal and mesenteric lymph nodes spread tumor cells, then a secondary lymphoma is formed in the small intestine. Types of small bowel cancer include ring cell, undifferentiated, and unclassified. The growth form is exophytic and endophytic.

Stages of small intestine cancer:

1. Stage 1 cancer of the small intestine - a tumor within the walls of the small intestine, no metastases;
2. Stage 2 cancer of the small intestine - the tumor goes beyond the walls of the intestine, penetration into other organs begins, metastases are absent;
3. Stage 3 small intestine cancer - metastasis to the nearest lymph nodes, germination to other organs, distant metastases - are absent;
4. small intestine cancer stage 4 - metastasis in distant organs (liver, lungs, bones, etc.).

Diagnosis of small bowel cancer

How to recognize bowel cancer early stage? It depends on what treatment will be applied, the patient's condition and the prognosis for survival.

Diagnosis of small intestine cancer is carried out by popular methods:

• x-ray examination;
• fibrogastroscopy;
• angiography of the vessels of the peritoneal cavity;
• laparoscopy;
• colonoscopy;
• CT and MRI;
• biopsy study: establish the type of cells and their degree of malignancy;
• electrogastroenterography: detect small bowel motility disorders characteristic of cancer.

How to identify bowel cancer, the symptoms of which do not manifest themselves in anything specific? During this period, it is very important to confirm or refute the suspicion of cancer, because the sooner treatment begins, the easier it is for the patient to transfer its stages, the greater the chance of a positive result. When the symptoms appear, the oncoprocess can be considered neglected, and the moment of early treatment will be missed.

Important! TO early symptoms refers to a “malicious” condition that should alert any person - this is an unwillingness to work or do household chores due to increased weakness and fatigue. The skin becomes pale and "transparent". The patient constantly has heaviness in the stomach, he does not want to eat at all. Following this, dyspeptic disorders appear: nausea, vomiting, pain and heartburn, even from water.

When contacting a doctor, they immediately prescribe and examine a blood test for bowel cancer. According to the general basic blood test, anemia, the patient's condition, and the presence of inflammation can be detected. According to the level of ESR and hemoglobin - problems in the liver, kidneys and blood. The composition of the blood may indicate some diseases, including oncology.

In the blood, tumor markers for cancer of the small intestine are detected. The most informative and common oncomarkers are alpha-fetoprotein, total PSA / free PSA, CEA, CA-15.3, CA-125, CA-19.9, CA-72.4, CYFRA-21.1, hCG and cytokeratin .

For example, with the help of tumor markers CA 19.9 and CEA (cancer-embryonic antigen), screening diagnostics colon cancer. If CEA is determined, then you can find out the staging before the operation and monitor the patient with a diagnosis of colorectal cancer after it. As the disease progresses, the serum CEA level will rise. Although it may grow and not in connection with the tumor, and in the later stages, colorectal cancer can be detected without an increase in CEA in the blood.

Endoscopic diagnosis, open biopsy of the intestine are the main methods for confirming oncology of the small intestine.

Small bowel cancer treatment

Treatment of cancer of the small intestine: duodenal, jejunal and ileal intestines are carried out depending on the type of tumor and stage. The main method is bowel resection and removal of oncology.

With a confirmed diagnosis of small intestine cancer, surgery reduces symptoms and increases life expectancy. If it is not possible to remove malignant tumors of the small intestine at a late stage or it is found that the tumor is sensitive to chemotherapy, drugs that prevent the growth of cancer cells are used.

After a palliative operation (relieving the suffering of the patient), chemotherapy (polychemotherapy) is performed, but without radiation.

After the operation, an additional diagnosis of intestinal motility is carried out by the method of electrogastroenterography, so that dangerous complication- intestinal paresis.

To alleviate the patient's condition after surgery and chemotherapy in complex therapy introduced ethnoscience with bowel cancer: tinctures for alcohol, infusions and decoctions of medicinal herbs, mushrooms and berries. Appropriate nutrition in bowel cancer prevents paresis, nausea and vomiting, improves gastrointestinal motility.

Forecast and prevention of cancer of the small intestine (intestine)

Prevention of small intestine cancer consists in the timely removal of benign neoplasms, polyps, constant monitoring of patients with chronic inflammatory processes of the gastrointestinal tract by specialists, the transition to a healthy diet and lifestyle, and the rejection of bad habits.

If the treatment was carried out, and the bowel cancer was removed, how long do people live? If there are no regional and distant metastases, the tumor is removed, the survival rate in the next 5-year period can be 35-40%.

Conclusions! If the tumor is operable, a wide resection of a section of the intestine with lymph nodes and mesentery is performed within the boundaries of healthy tissues. To restore the integrity of the gastrointestinal tract, enteroenteroanastomosis is applied - the small intestine into the small intestine or enterocoloanastomosis - the small intestine into the large intestine.

With duodenal cancer, as part of a thin one, duodenectomy is performed and sometimes - distal resection stomach or pancreas (pancreatoduodenal resection). With advanced oncology of the small intestine, a bypass anastomosis is applied between the loops, which remain unaffected. Surgical treatment is complemented by chemotherapy.

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Columnar epitheliocytes- the most numerous cells of the intestinal epithelium, performing the main absorption function of the intestine. These cells make up about 90% of the total number of intestinal epithelial cells. A characteristic feature of their differentiation is the formation of a brush border of densely located microvilli on the apical surface of the cells. The microvilli are about 1 µm long and about 0.1 µm in diameter.

The total number of microvilli per surfaces one cell varies widely - from 500 to 3000. Microvilli are covered on the outside with glycocalyx, which adsorbs enzymes involved in parietal (contact) digestion. Due to microvilli, the active surface of intestinal absorption increases 30-40 times.

Between epitheliocytes in their apical part, contacts such as adhesive bands and tight contacts are well developed. The basal parts of the cells are in contact with the lateral surfaces of neighboring cells through interdigitations and desmosomes, and the base of the cells is attached to the basement membrane by hemidesmosomes. Due to the presence of this system of intercellular contacts, the intestinal epithelium performs an important barrier function, protecting the body from the penetration of microbes and foreign substances.

goblet exocrinocytes- these are essentially unicellular mucous glands located among columnar epitheliocytes. They produce carbohydrate-protein complexes - mucins, which perform a protective function and promote the movement of food in the intestines. The number of cells increases towards the distal intestine. The shape of the cells changes in different phases of the secretory cycle from prismatic to goblet. In the cytoplasm of cells, the Golgi complex and the granular endoplasmic reticulum are developed - centers for the synthesis of glycosaminoglycans and proteins.

Paneth cells, or exocrinocytes with acidophilic granules, are constantly located in the crypts (6-8 cells each) of the jejunum and ileum. Their total number is approximately 200 million. In the apical part of these cells, acidophilic secretory granules are determined. Zinc and a well-developed granular endoplasmic reticulum are also detected in the cytoplasm. The cells secrete a secret rich in the enzyme peptidase, lysozyme, etc. It is believed that the secret of the cells neutralizes the hydrochloric acid of the intestinal contents, participates in the breakdown of dipeptides to amino acids, and has antibacterial properties.

endocrinocytes(enterochromaffinocytes, argentaffin cells, Kulchitsky cells) - basal-granular cells located at the bottom of the crypts. They are well impregnated with silver salts and have an affinity for chromium salts. There are several types of endocrine cells that secrete various hormones: EC cells produce melatonin, serotonin and substance P; S-cells - secretin; ECL cells - enteroglucagon; I-cells - cholecystokinin; D-cells - produce somatostatin, VIP - vasoactive intestinal peptides. Endocrinocytes make up about 0.5% of the total number of intestinal epithelial cells.

These cells are updated much more slowly than epitheliocytes. Methods of historadioautography established a very rapid renewal of the cellular composition of the intestinal epithelium. This happens in 4-5 days in the duodenum and somewhat more slowly (in 5-6 days) in the ileum.

lamina propria of the mucous membrane The small intestine is composed of loose fibrous connective tissue containing macrophages, plasma cells, and lymphocytes. There are also both single (solitary) lymph nodules and larger accumulations of lymphoid tissue - aggregates, or group lymph nodules (Peyer's patches). The epithelium covering the latter has a number of structural features. It contains epithelial cells with microfolds on the apical surface (M-cells). They form endocytic vesicles with antigen and exocytosis transfer it to the intercellular space where lymphocytes are located.

Subsequent development and plasma cell formation, their production of immunoglobulins neutralizes the antigens and microorganisms of the intestinal contents. The muscularis mucosa is represented by smooth muscle tissue.

In the submucosa basis of the duodenum are duodenal (Brunner's) glands. These are complex branched tubular mucous glands. The main type of cells in the epithelium of these glands is mucous glandulocytes. The excretory ducts of these glands are lined with border cells. In addition, Paneth cells, goblet exocrinocytes and endocrinocytes are found in the epithelium of the duodenal glands. The secret of these glands is involved in the breakdown of carbohydrates and the neutralization of hydrochloric acid coming from the stomach, the mechanical protection of the epithelium.

Muscular layer of the small intestine consists of inner (circular) and outer (longitudinal) layers of smooth muscle tissue. In the duodenum, the muscular membrane is thin and, due to the vertical location of the intestine, practically does not participate in peristalsis and the promotion of chyme. Outside, the small intestine is covered with a serous membrane.

EPITHELIUM OF THE SMALL INTESTINE

Epithelium (E) of the small intestine consists of two types of epithelial cells: suction and goblet, lying on the basement membrane (BM). The absorptive and goblet cells are connected by junctional complexes (SCs) and multiple lateral interdigitations (LIs). Intercellular gaps (IS) are often formed between the basal parts. Chylomicrons (X, a class of lipoproteins formed in the small intestine during lipid absorption) can circulate between these clefts; lymphocytes also penetrate here (L). Absorbing cells live for about 1.5-3.0 days.

Suction cells (VC)- high prismatic cells with an elliptical, often invaginated, nucleus (N), located in the lower part of the cell body. The nucleoli, Golgi complex (G) and mitochondria are well developed. The granular endoplasmic reticulum often continues into a granular one. The cytoplasm contains some lysosomes and free ribosomes.

The apical pole of the cell is polygonal in shape. Microvilli (Mv) are covered with a thick layer of glycocalyx (Gk), in some places in the figure it is partially removed. Microvilli and glycocalyx form a brush border (BBC) that increases the intestinal absorptive surface to 900 m2.

Goblet cells (BC)- basophilic cells scattered among absorbing cells. In active cells, the nucleus is cup-shaped and located at the basal pole of the cell. The cytoplasm contains mitochondria, a well-developed supranuclear Golgi complex, several cisterns of the granular endoplasmic reticulum oriented parallel to each other, and many free ribosomes.

The last two structures are responsible for goblet cell basophilia. Numerous mucous droplets (SC) surrounded by a single-layer membrane arise from the Golgi complex, filling the entire supranuclear cytoplasm and giving the cells a goblet shape. Droplets are released from cells by fusion of their surrounding membranes with the apical plasmalemma. After the release of mucous droplets, goblet cells become invisible in a light microscope. Goblet cells are able to replenish the cytoplasm with mucous droplets during 2-3 secretory cycles, since their life span is about 2-4 days.

Products goblet cells CHIC-positive and metachromatic, as it consists of glycoproteins and glycosaminoglycans; it serves to lubricate and protect the suction cells. Networks of capillaries (Cap) and reticular fibrils (RF) belonging to the lamina propria (LP) of the mucous membrane are located immediately below the epithelial basement membrane (BM). Reticular fibers serve, among other things, to attach thin, vertically oriented smooth muscle cells (MCs) to the basement membrane. Their contractions shorten the intestinal villi. At some distance from the epithelium, the lactiferous vessels (MS) begin with blind extensions. Numerous openings (O) are distinguishable between endothelial cells through which chylomicrons enter the lymphatic circulation. Anchor filaments (AF) are also noted, which attach the lactiferous vessels to the network of collagen fibers.

A large number of collagen (KB) and elastic (EV) fibers pass through the lamina propria. In the network of these fibrils there are lymphocytes (L), plasma cells (PC), histiocytes (G) and eosinophilic granulocytes (EG). Fibroblasts, fibrocytes (F), and some reticular cells are permanent cells of the lamina propria.

ABSORPTION (ABSORPTION) OF LIPID IN THE SMALL INTESTINE

The function of absorptive cells is to absorb nutrients from the intestinal cavity. Since the absorption of proteins and polysaccharides is difficult to detect morphologically, we will describe lipid absorption.

Mechanism lipid absorption is divided into enzymatic cleavage of fats into fatty acids and monoglycerides and the entry of these products into absorbent cells, where resynthesis of new lipid droplets - chylomicrons (X) occurs. Then they are ejected into the basal intercellular fissures, cross the basal lamina and enter the lacteal vessel (MS).

Chylomicrons are emulsified fat droplets that have a milky color, therefore all lymphatic intestinal vessels are called milky.

Colon contains a mucous membrane that does not form folds, with the exception of its distal (rectal) section. There are no villi in this part of the intestine. The intestinal glands are long and characterized by a large number of goblet and limbic cells and a low content of enteroendocrine cells.

Border cells- columnar, with short microvilli of irregular shape. The large intestine is well adapted to perform its main functions: the absorption of water, the formation of fecal matter and the production of mucus. Mucus is a highly hydrated gel that not only acts as a lubricant on the surface of the intestine, but also coats bacteria and various particles. Water absorption is carried out passively following the active transport of sodium through the basal surfaces of epithelial cells.

Histology of the colon

Own plate rich in lymphoid cells and nodules, which often extend into the submucosa. Such a powerful development of lymphoid tissue (LALT) is associated with a huge population of bacteria in the colon. The muscular layer includes longitudinal and circular layers.

This shell differs from that in the small intestine, because the bundles of smooth muscle cells of the outer longitudinal layer are assembled into three thick longitudinal belts - intestinal tapes (Latin teniae coli). In the intraperitoneal areas of the large intestine, the serous membrane contains small hanging protrusions consisting of adipose tissue - fatty appendages (Latin appendices epiploicae).

Iron in the large intestine. Its border and mucous goblet cells are visible. Note that the goblet cells secrete a secret and begin to fill the lumen of the gland with it. Microvilli on the border cells are involved in the process of water absorption. Stain: pararosaniline-toluidine blue.

IN anal(anal) section of the mucous membrane forms a series of longitudinal folds - Morgagni's rectal columns. Approximately 2 cm above the anus, the intestinal mucosa is replaced by stratified squamous epithelium. In this area, the lamina propria contains a plexus formed by large veins, which, with their excessive expansion and varicose changes, give hemorrhoids.

Small bowel cancer: characteristic signs and symptoms

What are the signs and symptoms of a small bowel cancer diagnosis? What is the etiology of the disease and the principles of treatment?

Cancer of the small intestine

The small intestine is made up of several sections. Depending on which of them develops an oncological disease, there are:

The most common type of cancer is in the duodenum.

Cancer develops from various intestinal tissues and can spread to other organs. Depending on the tissues from which the tumor developed, several histological types are distinguished:

1. Lymphoma that develops from tissues rich in immune cells.
2. Sarcoma, which develops from smooth muscles that provide peristalsis of the small intestine.
3. Adenocarcinoma that develops from mucosal cells. This is the most common form.

Different types of cancer have different etiologies and clinical manifestations suggest different approaches to treatment and prognosis.

Clinical manifestations

Based on the degree of development of the disease, there are several stages of cancer development, which are manifested by certain symptoms:

1. The tumor develops in the tissue of the intestinal wall. Spread to other organs and metastases are absent. At this stage, most often there are no symptoms that may cause concern to the patient.
2. The tumor spreads to neighboring organs. Metastases are absent.
3. The appearance of metastases in the nearest lymph nodes, in the organs - are absent.
4. The presence of metastases in distant organs.

The first symptoms of the disease appear with the development of a pronounced narrowing of the intestine or ulceration of the tumor, which are prolonged pains in the epigastric region. This is accompanied by the following symptoms:

• weight loss;
• anemia (a drop in hemoglobin levels), which causes weakness and dizziness;
• vomiting if the tumor is localized in the upper jejunum;
• loose stools with mucus;
• signs of intestinal obstruction;
• obvious or hidden blood loss, especially often manifested in sarcoma;
• increased bilirubin levels in liver metastases;
• yellow skin color;
• eye sclera.

Causes of small intestine cancer

Reliably the causes of the development of cancer of the small intestine have not been identified. Based clinical research and statistical data, it is known that the risk of developing the disease is highest in the following cases:

• in cases of small bowel cancer, it was observed in direct relatives;
• in the presence of chronic inflammatory diseases small intestine, destroying the mucosa (Crohn's disease, celiac disease);
• in the presence of polyps in the intestine;
• in the presence of cancer of other organs;
• when exposed to radiation;
• when smoking, alcohol abuse, regular use of dried, salty, smoked foods, with a high content of animal fat (fatty meats, lard).

Small bowel cancer is more common:

• in developing countries in Asia;
• in blacks;
• among men;
• among people over 60 years of age.

Diagnosis and treatment methods

If you notice unpleasant symptoms, you should contact a qualified specialist as soon as possible. In the presence of cancer, early diagnosis is the most important condition for a favorable prognosis.

Research methods that allow diagnosing the presence of cancer, the degree of its development and spread:

1. FGDS (fibrogastroduodenoscopy) is a method of instrumental examination of the inner surface of the esophagus, stomach and duodenum by inserting a probe through the nasal sinuses or mouth opening.
2. Colonoscopy is a method of instrumental examination of the inner surface of the large intestine by inserting a probe through the anus.
3. Laparoscopy is a method of examination or surgical intervention in which a skin incision is made in the required area and a miniature camera and surgical instruments are inserted into the abdominal region.
4. ultrasound ( ultrasound procedure) abdominal organs.
5. CT ( CT scan), MRI (magnetic resonance imaging) of the small intestine.
6. Blood chemistry.
7. X-ray examination of the chest organs.
8. Bone scintigraphy.

When conducting such instrumental examinations as FGDS, colonoscopy, laparoscopy, a biopsy is performed (taking a tissue sample for a detailed laboratory study) to examine tissues in detail for the presence of cancer cells and determine the type of tumor.

Surgical treatment is the most effective method therapy for small intestine cancer. The operation consists in the removal (ectomy) of the tumor and the affected tissues and lymph nodes. Artificial restoration of removed tissues can also be carried out in several ways:

1. Enteroanastamosis is a surgical connection between intestinal loops.
2. Enterocoloanastomosis is a surgical connection between the loops of the large and small intestines.

Resection (excision) is prescribed only by a doctor in the absence of contraindications. The type of surgical intervention depends on the stage of development of the disease and the degree of spread.

At an advanced stage of cancer, when it is not possible to carry out an extensive resection, surgical implantation of a bypass anastomosis in a healthy part of the organ is prescribed.

At an earlier stage of cancer development, the removal of pathological tissue is carried out, the more favorable the prognosis for the patient.

Conservative treatment. Chemotherapy or radiation therapy is an adjunct to the surgical treatment of small bowel cancer. Radiation therapy is the effect of high frequency radiation on malignant cells. Chemotherapy is the intravenous or oral administration of drugs to the body.

The above procedures cause many side effects, including general weakness and malaise, nausea, vomiting, diarrhea, headaches, hair loss, impaired hematopoiesis, weakness, diarrhea, the appearance of ulcers on the oral mucosa, disruption of the immune system.

An important condition in the treatment of small intestine cancer is proper nutrition, which includes the following conditions:

1. Exclusion from the diet of foods containing animal fats.
2. Inclusion in the diet of foods with sufficient fiber content, fish oil, soy, indole-3 carbinol.
3. Refusal of alcohol and cigarettes.

When running oncological disease When the operation is inappropriate due to its ineffectiveness, radiation and chemotherapy may be prescribed. Radiation therapy may be given to relieve symptoms.

Preventive actions

With early diagnosis and treatment, a complete cure is possible. Small intestine cancer develops for a long time and does not metastasize for a long time due to the fact that it is poorly supplied with blood and cancer cells do not spread so quickly throughout the body.

Even after the operation, the patient must undergo regular examinations by the oncologist and take necessary tests. It is also necessary to closely monitor the health status of people at risk.

These tumors are observed in all parts of the small intestine;

14% of malignant neoplasms are sarcomas. The frequency of sarcomas does not depend on sex, the peak frequency in the sixth to eighth decades of life. Usually, mesenchymal tumors of this localization develop in younger patients than cancer, and are more common than AK and carcinoid. Intussusception is a common complication of mesenchymal tumors of the small intestine. The prognosis for sarcoma depends on the mitotic index, size, depth of invasion, and the presence or absence of metastases. The indicator of 5-year life expectancy of patients is 45% (with carcinoid - 92%; with AK - 63%). In sarcoma of the small intestine, the prognosis is worse than in similar tumors of the colon, stomach, and esophagus. Macroscopic appearance, histological structure and possibilities of cytological diagnostics are given in Ch. about the stomach.

Gastrointestinal stromal tumors (GISTs) are significant; leiomyoma, leiomyosarcoma, Kaposi's sarcoma, angiosarcoma rarely found in the small intestine (the histological and cytological picture is similar to tumors of the esophagus and stomach, see Chapter IV and V). Leiomyoma is more often localized intraparietal, large tumors bulge into the lumen, ulcerate and bleed.

genetic features. In small, especially malignant GIST of the intestine, as in similar tumors of the stomach, mutations of the c-kit gene in exon 11 are found. Comparative genomic hybridization revealed deletions on chromosomes 14 and 22, which is also characteristic of gastric GIST. The fundamental criterion for the diagnosis of AK is the presence of invasion of the muscularis lamina of the mucous membrane, which in practice is not always easy to determine, because. highly differentiated AK mimics an adenoma. On the other hand, in some adenomas, acellular mucus penetrates the intestinal wall, mimicking invasion. If the wall of the appendix contains acellular mucus, then the diagnosis of adenoma is possible only with an intact muscular plate. Sometimes AK is so highly differentiated that it is difficult to verify it as a malignant tumor. Highly differentiated AK of the appendix grows slowly, clinically creates a picture of pseudomyxoma of the peritoneum. Most AKs of the appendix are mucosal. If there are more than 50% of cricoid cells, then the tumor is called cricoid cell. Non-mucosal tumors proceed in the same way as in the colon. Metastases in the lymph nodes are observed late.

The indicator of 5-year life expectancy with localized AK of the appendix is ​​95%, with mucous cystadenocarcinoma - 80%; with distant metastases of these tumors - 0% and 51%, respectively. With a poor prognosis in AK of the appendix, an advanced stage is combined, high degree malignancy, non-mucosal tumor. With the complete removal of the tumor, an extension of life expectancy is noted.

The histological and cytological picture of AK is similar to that in similar tumors of other localizations.

Pseudomyxoma of the peritoneum represented by mucus on the surface of the peritoneum. A clear picture is due to the highly differentiated mucosa of the AK (Fig. 175-182), and there are few cells, the cellular component grows slowly, and the mucus arrives quickly. The tumor is poorly manifested on the surface of the peritoneum, while large volumes of mucus are located in the omentum, on the right under the diaphragm, in the hepatic space, in the Treitz ligament, in the left sections of the colon, in the pelvic cavity. Occasionally, mucous cysts are found in the spleen. In these cases, the tumor tends to remain in the abdominal cavity for many years.

Most cases of peritoneal pseudomyxoma arise from primary cancer of the appendix, occasionally spreading from the ovary, gallbladder, stomach, PBMC, pancreas, fallopian tubes, urachus, lung, breast. With pseudomyxoma of the peritoneum, weight loss, a high degree of malignancy with histological examination, morphological invasion of underlying structures are factors of poor prognosis.

In half of the cases of peritoneal pseudomyxoma, loss of heterozygosity for one or two polymorphic microsatellite loci was revealed, which indicates the monoclonal nature of the tumor. Subject to compliance clinical picture a cytological diagnosis is established reliably: "pseudomyxoma".

Carcinoid tumor is the most common (50-75%) primary tumor of the appendix; -19% of all gastrointestinal carcinoids are localized in the appendix, mainly in its distal part; the tumor is more often diagnosed in women. Tubular carcinoid occurs at a significantly younger age than goblet cell carcinoid (mean age 29 and 53 years, respectively). An asymptomatic lesion is often observed (a single tumor nodule is found by chance in the appendectomy material). Rarely, a carcinoid can cause obstruction of the lumen of the appendix, leading to appendicitis. Carcinoid syndrome occurs extremely rarely, always with metastases in the liver and retroperitoneal space.

The EC-cell carcinoid of the appendix is ​​a well-demarcated dense nodule, on the section it is opaque, grayish-white, in size<1 см. Опухоли >2 cm are rare, most located at the apex of the appendix. Goblet cell carcinoid and AK carcinoid are found in any part of the appendix in the form of a diffuse infiltrate, 0.5–2.5 cm in size.

In most cases, with carcinoid of the appendix, the prognosis is favorable. The tumor and metastases often grow slowly. Clinically non-functioning appendix lesions that do not grow into vessels, size<2 см, обычно излечивают полной местной эксцизией, в то время как размеры >2 cm, invasion of the mesentery of the appendix and metastases indicate the aggressiveness of the lesion. Localization of the tumor at the base of the appendix involving the edge of the incision or the caecum is unfavorable prognostically, requiring at least partial resection of the caecum in order to avoid residual tumor and recurrence. The frequency of regional metastases of appendix carcinoid is 27%, distant metastases - 8.5%. Indicators of 5-year life expectancy with local carcinoid of the appendix are 94%, with regional metastases 85%, with distant metastases 34%. Goblet carcinoid is more aggressive than normal carcinoid, but less aggressive than appendix AK; tubular carcinoid, on the contrary, has a favorable prognosis.

Histological picture: most appendix carcinoids are EC-cell enterochromaffin tumors; L-cell carcinoids, as well as mixed endocrine-exocrine cancers, are rare.

The structure of the EC-cell Argentaffin carcinoid of the appendix is ​​similar to the structure of a similar carcinoid of the small intestine (see above). Most tumors invade the muscle layer, lymphatic vessels, and perineurium, and in 2/3 cases, the mesentery of the appendix and peritoneum; however, they rarely metastasize to The lymph nodes and distant organs, unlike ileal carcinoid. In appendix carcinoid, supporting cells are seen around nests of tumor cells; in contrast, supporting cells are absent in EC-cell carcinoids of the ileum and colon.

L-cell carcinoid producing glucagon-like peptides (GLP-1 and GLP-2, enteroglucagon glycentin, oxyntomodulin) and PP/PYY is non-argentaffin; often has a size of 2-3 mm; characteristic tubular from small cylindrical cells and trabecular structures in the form of long strands (type B); similar carcinoids are often found in the rectum.

Goblet cell carcinoid, usually 2–3 mm in size, grows in the submucosa, invades the appendix wall concentrically, and consists of small, round nests of cricoid cells resembling normal intestinal goblet cells, except for the compressed nuclei. Some of the cells are located in isolation, Pannet cells with lysosomes and foci resembling Brunner's glands are visible. When individual goblet cells merge, extracellular "lakes" of mucus are formed. The picture is difficult to distinguish from the mucosa of the AK, especially when the tumor invades the wall and distant metastases. There are argentaffin and argyrophilic tumors. Immunohistochemically, the endocrine component gives positive reaction on chromogranin A, serotonin, enteroglucagon, somatostatin and PP; goblet cells express cancer-embryonic antigen. EM shows dense endocrine granules, drops of mucus, sometimes both components in the cytoplasm of the same cell.

Tubular carcinoid is often misdiagnosed as AK metastasis because the tumor is represented by small discrete tubules, sometimes with mucus in the lumen. Often meet short trabecular structures; solid nests are usually absent. In isolated cells or in small groups of cells, a positive argentaffin and argyrophilic reaction is often detected. In contrast to cancer, an intact mucosa, structure orderliness, and the absence of cell atypia and mitosis are characteristic. The tumor is positive for chromogranin A, glucagon, serotonin, IgA and negative for protein S 100. An exocrine-endocrine tumor consists of goblet cells and structures characteristic of carcinoid and AK.

Genetic features: unlike colonic AK, KRAS gene mutations were not found in typical carcinoid and goblet cell carcinoid of the appendix, with the latter in 25% of cases TP53 mutations were found (mainly G:C->A:T transitions).

Cytological diagnosis: in routine smears, EC-cell and L-cell carcinoids are cytologically diagnosed as typical carcinoid NOS. Goblet cell carcinoid, tubular carcinoid, exocrine endocrine carcinoma cannot be cytologically identified as such. small cell cancer has properties similar to those of this tumor in other parts of the gastrointestinal tract.

Rare tumors of the appendix: in the mucosa and submucosa, a neurinoma is found, occasionally an axial neurinoma, which causes obliteration of the appendix lumen. The histological structure is similar to neuron in other localizations. GIST in the appendix is ​​rarely found. Kaposi's sarcoma in this organ may be part of acquired immunodeficiency syndrome. Primary appendix AL (Burkitt AL) is very rare, more often tumors of neighboring organs spread to the appendix.

Secondary tumors uncharacteristic for the appendix: isolated cases of metastases of cancer of the gastrointestinal tract, gallbladder, genitourinary tract, breast, lung, thymoma, melanoma have been published. Involvement of the serosa of the appendix is ​​often associated with transintestinal spread. The cytological picture of tumors is similar to that of tumors of other organs.

Stomach Secretory. The function is to produce gastric juice by the glands. mechanical function

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In the large intestine, water is absorbed from the chyme and feces are formed. In the large intestine

In the small intestine, the process of absorption of the breakdown products of proteins, fats and carbohydrates into the blood and lymphatic vessels also takes place. Also, the small intestine performs a mechanical function: it pushes the chyme in the caudal direction.

Structure. The wall of the small intestine consists of a mucous membrane, submucosa, muscular and serous membranes.

From the surface, each intestinal villus is lined with a single-layer cylindrical epithelium. In the epithelium, three types of cells are distinguished: border, goblet and endocrine (argyrophilic).

Enterocytes with a striated border make up the bulk of the epithelial layer covering the villus. They are characterized by a pronounced polarity of the structure, which reflects their functional specialization: ensuring the resorption and transport of substances from food.

Goblet intestinal - in structure, these are typical mucous cells. They show cyclical changes associated with the accumulation and subsequent secretion of mucus.

The epithelial lining of intestinal crypts contains the following types of cells: bordered, borderless intestinal cells, goblet, endocrine (argyrophilic) and intestinal cells with acidophilic granularity (Paneth cells).

The lamina propria of the small intestine mucosa mainly consists of a large number of reticular fibers. They form a dense network throughout the lamina propria and, approaching the epithelium, participate in the formation of the basement membrane.

The submucosa contains blood vessels and nerve plexuses.

The muscular coat is represented by two layers of smooth muscle tissue: inner (circular) and outer (longitudinal).

The serous membrane covers the intestine from all sides, with the exception of the duodenum. The lymphatic vessels of the small intestine are represented by a very widely branched network. In each intestinal villus there is a centrally located, blindly ending at its top, a lymphatic capillary.

Innervation. The small intestine is innervated by sympathetic and parasympathetic nerves.

Afferent innervation is carried out by a sensitive musculo-intestinal plexus formed by sensitive nerve fibers of the spinal ganglia and their receptor endings.

Efferent parasympathetic innervation is carried out by the musculo-intestinal and submucosal nerve plexuses.

Structure thin guts. Thin intestine(intestinum tenue) - the next section of the digestive system after the stomach.

Thin intestine. IN thin gut all types of nutrients are chemically processed: proteins, fats and carbohydrates.

If symptoms of bloat are present thin guts it is necessary to immediately carry out the operation, without waiting for the appearance of the entire classical picture of the disease.

Iliac intestine- a continuation of the lean one, its loops lie in the lower right part of the abdominal cavity. In the cavity of the small pelvis lie the last loops thin guts.

Practically thin intestine can be implemented in thin, thin in thick and thick in thick. Ileocecal intussusception is the most common.

thick intestine. In thick gut water is absorbed from the chyme and feces are formed.

Crypts in the colon gut better developed than thin.

Colon intestine located around the loops thin guts, which are located in the middle of the bottom.

The structure of the colon guts. Colon intestine located around the loops thin guts, which are located in the middle of the lower floor of the abdominal cavity.

The structure of the thick and blind guts. thick intestine(intestinym crassum) - continued thin guts; is the final section of the digestive tract.

Thin intestine(intestinum tenue) - the next section of the digestive system after the stomach; zakan.