Human large intestine

The large intestine is the section of the gastrointestinal tract that follows the small intestine and ends at the anus. It performs many functions: the absorption of water, the formation of feces, the synthesis of certain vitamins. The large intestine is an organ that has its own diseases and features of their course.

What is important to know about the human colon

Where is the human large intestine

1. The large intestine is located in the abdominal cavity. It begins with the caecum in the right iliac region. It is separated from the loops of the small intestine by the ileocecal valve. This is a kind of sphincter that regulates the movement of digested food from the small intestine to the large intestine. Also, a vermiform appendix (appendix) departs from the caecum.
2. After the caecum comes the ascending part of the colon. It is on the right, and its upper part borders on the liver.
3. In the liver, the colon forms a bend, turns 180 degrees and passes into the transverse colon. It is located across the abdominal cavity, which is why it has such a name.
4. In the left hypochondrium, the intestine again makes a bend and turn and passes into the descending colon. It is located on the left and descends to the iliac fossa.
5. The sigmoid colon is located in the iliac fossa. This is an S-shaped formation that passes into the rectum.
6. The rectum is the final section of the large intestine. Behind it borders on the sacrum and coccyx. The rectum has a pelvic area (where feces accumulate) and an anal canal that ends at the anus.

What does the human colon look like and how does it work?

The large intestine is a hollow tubular organ that is located in the abdominal cavity in the form of the letter “P”.

The main task of the large intestine is the transformation of the digested contents from the small intestine into feces and removing them from the body. This process has several components:

• Muscles – they provide peristalsis (wave-like contraction) and the promotion of intestinal contents. In the colon, peristalsis does not depend on the will of the person and occurs independently 3-4 times a day.
• Nerve endings in the rectal mucosa. When they are irritated under the pressure of fecal masses, the signal is transmitted to the spinal cord, where the control center for defecation is located.
• Nerve endings of the internal sphincter of the anus – this sphincter is constantly in tension, and with the accumulation of feces (and their pressure on the nerve endings) in the lumen of the rectum, it relaxes.
• Central nervous system – a person can control the external sphincter and, with the accumulation of feces, consciously relax it.

Why can the human colon hurt?

Pain in the colon can be caused by a variety of diseases. Let’s consider the main ones.

Appendicitis

Appendicitis is an inflammatory process in the appendix that requires surgical intervention. The causes of appendicitis are not fully understood.

Symptoms:

• abdominal pain that begins in the umbilical or epigastric region and gradually goes to the right iliac;
• loss of appetite;
• nausea, vomiting;
• fever;
• frequent loose stools.

Colon Cancer

Colon cancer is a malignant tumor of the lining of the colon. Its causes are not fully understood, but predisposing factors may be: heredity, inflammatory bowel disease (ulcerative colitis, Crohn’s disease), the prevalence of red and processed meat in the diet, and advanced age.

Symptoms:

• constipation and / or diarrhea;
• weight loss;
• fatigue;
• bleeding from the anus;
• aching pain in the abdomen;
• lack of appetite;
• flatulence;
• tension in the abdominal muscles.

Irritable Bowel Syndrome (IBS)

Irritable bowel syndrome is a functional disorder in which bowel movement is disturbed and unpleasant symptoms appear. Sometimes IBS with constipation, diarrhea, and sometimes a mixed version. The causes of the disease have also not been established. Possible predisposing factors may be: prolonged stress, infectious and inflammatory diseases of the gastrointestinal tract, regular overeating.

Symptoms:

• discomfort and pain in the abdomen, which are observed for a long time and decrease after a bowel movement;
• swelling;
• loose stools and/or constipation.

Megacolon

Megacolon is a pathology in which the large intestine is significantly enlarged in size. This may be a congenital defect or acquired (for example, due to a tumor).

Symptoms:

• prolonged constipation;
• flatulence;
• abdominal pain;
• an increase in the size of the abdomen.

Pseudomembranous colitis

Pseudomembranous colitis is an inflammation of the colon caused by the bacterium Clostridium difficile. The cause of this process is most often the wrong or unreasonable intake of antibiotics.

Symptoms:

• loose stools with the presence of mucus and blood;
• abdominal pain;
• fever;
• signs of intoxication.

Crohn’s disease

Crohn’s disease is an inflammatory process in the intestines. Feature – the formation of specific nodules – granulomas. Possible causes: disorders in the immune system, hereditary predisposition, infections, smoking.

Symptoms:

• abdominal pain and bloating;
• frequent loose stools;
• cramps in the abdomen, most often after eating.

Nonspecific ulcerative colitis (NSA)

Nonspecific ulcerative colitis is a chronic inflammation of the colon. The causes of the disease are not fully understood, but possible: hereditary predisposition, stress, infections, autoimmune factors.

Symptoms:

• frequent loose stools;
• stitching or aching pain in the abdomen in the left iliac region;
• flatulence;
• weight loss;
• lack of appetite.

Diverticular disease (DB) or diverticulosis

Diverticulosis is a chronic process in which diverticula are formed (sac-like protrusions of the intestinal wall). The diverticulum is formed from the mucosal and submucosal layers.

There are congenital and acquired protrusions. Acquired diverticulum is formed against the background of inflammatory diseases or increased pressure in the intestinal lumen. Diverticular disease develops when the diverticulum becomes inflamed.

Symptoms:

• pain in the left lower abdomen;
• bloating;
• temperature rise to 37,5–38,5˚С;
• constipation and feces of the “sheep” type.

Hemorrhoids

Hemorrhoids are varicose veins in the rectum or anus. Reasons: sedentary work, stress, frequent constipation, pregnancy, inflammation of the colon, fissures, infections.

Symptoms:

• pain in the anus (increased by the act of defecation, walking, sitting position);
• the presence of blood in the feces;
• foreign body sensation;
• prolapse of nodes from the lumen of the rectum.

How is the human colon treated?

To address the cause and symptoms of colon disease, doctors may prescribe the following medications:

Antispasmodics

Since most of the pain in the colon is associated with spasms, antispasmodics are prescribed to relieve them.

Antibacterial drugs

Antibiotics are prescribed when a bacterial infection is attached.

Antidiarrheals

If colon problems are accompanied by frequent loose stools, your doctor may prescribe antidiarrheal drugs, such as loperamide. At the same time, it is important to understand that antidiarrheal drugs themselves are a treatment, but only stop diarrhea and alleviate a person’s condition.

Laxatives

Laxatives include, for example, Duphalac. It is a polysaccharide that is excreted unchanged by the body and can be used both for the treatment and prevention of constipation. Another frequently prescribed drug is Mucofalk, which has an anti-inflammatory and enveloping effect, reduces intra-intestinal pressure and has a slight laxative effect.

Probiotics

Probiotics contain beneficial microorganisms that have a positive effect on the microflora of the gastrointestinal tract.

Preparations containing 5-acetylsalicylic acid

These drugs include Salofalk, Mesalazine, Sulfasalazine, which reduce the severity of inflammation in the intestine.

Immunosuppressants

Immunosuppressants include drugs such as Azathiaprine or Methotrexate. They are used, for example, in Crohn’s disease or ulcerative colitis and suppress the immune system, which perceives its own cells as foreign. The severity of inflammation decreases, and the disease becomes inactive.

Hormonal drugs (glucocorticosteroids)

Hormonal drugs reduce the severity of the inflammatory process. They are prescribed only by a doctor, while the dosage and duration of administration are selected individually for each patient.

Psychotropic drugs

Antidepressants, antipsychotics – drugs that help fight chronic depression, stress. The fact is that it is stress that can be a provoking factor in the development of irritable bowel syndrome, nonspecific ulcerative colitis.

Biological genetically engineered drugs (GEBP)

GIBP are drugs of biological origin, which are obtained through genetic engineering and are aimed at suppressing the immune-inflammatory process.

Surgical method

Surgical treatment is most often used in oncology. The amount of surgery depends on the location and volume of the tumor. If necessary, a colostomy can be created (removal of the colon to the abdominal wall for fecal discharge).

Chemo-and/or radiation therapy

These methods are used in oncology: they help to reduce the tumor, prevent the spread of metastases and reduce the severity of symptoms, which will greatly facilitate the life of a person even at advanced stages of cancer.

How to keep your colon healthy at home

Keeping your colon healthy at home is pretty easy. To do this, you need to follow a few simple rules.

1. Eat more vegetables and fruits (fiber is important for normal peristalsis).
2. Avoid overeating and snacking on the go.
3. Divide the daily meal into 4-6 times (it is important to avoid prolonged fasting).
4. Avoid constipation.
5. Treat inflammatory diseases of the colon.
6. Every 3 years, undergo an examination by a doctor, if necessary, undergo a colonoscopy.
7. Donate stool for occult blood annually.

Popular questions and answers

We discussed important issues related to the colon with therapist Tatyana Pomerantseva.

Sources of:

1. Clinical recommendations “Crohn’s disease” 2013-2017;
2. Clinical recommendations “Irritable bowel syndrome” 2013-2017;
3. 2000-2022. REGISTER OF DRUGS OF RUSSIA® RLS ®
4. Kraev A.V. Human anatomy. Volume 1 – 1978
5. Vermann K., Freumorgen P.. Diverticulosis and diverticulitis of the colon / Sci. row S. Sitkin. — Freiburg: Dr. Falk Pharma GmbH, 2007
6. Clinical anatomy and operative surgery of the colon, manual, Irkutsk 2010