Large Intestine (Human Anatomy): Image, Functions, Diseases and Treatments

The last section of your digestive system's long, tube-like gastrointestinal (GI) tract, which is where food ultimately exits your body, is the large intestine.

It proceeds from the small intestine and terminates at the anal canal, which is where bodily waste from food is expelled. When you poop, the large intestine removes food waste from the body by converting it into stool.

• Although the large intestine is one continuous tube, different processes take place in various parts of it. The colon, rectum, and anus are its three component parts. Partitioning is also possible for the colon. The six-inch-long entry point is known as the cecum.
• The ascending colon (travelling up), the transverse colon (travelling across to the left), the descending colon (travelling down), and the sigmoid colon make up the remainder of the colon.What's left of the food must be dehydrated in the colon in order to become faeces.
• It accomplishes this by gradually absorbing electrolytes and water as its muscular system moves the waste. While this is happening, bacteria in your colon feed on the waste and further degrade it, completing the chemical portion of digestion.
• The cecum starts the colon. The cecum ends in a pouch because the small intestine feeds into it through the ileocecal valve. This pouch, the first 6 inches of the colon, is also the broadest section of the large intestine When filled, the cecum starts colon muscular motions.
• When these segments encircle the small intestine. The ascending and transverse colon absorb water and electrolytes, making food waste in the descending colon mostly solid. Mucus binds and lubricates food waste in the dehydrated colon.
• The large intestine churns food against its mucous lining and moves it with muscle contractions, like the small intestine This area digests without enzymes like the small intestine.
• The sigmoid colon delivers food waste to the rectum as poop. Your poop now contains indigestible matter, dead intestinal mucosa cells, and small amounts of mucus and water. The large intestine excretes about 5 ounces of liquid food. Poop in the rectum causes defecation.
• Poop exits through the anus. The internal sphincter releases poop automatically Nerve signals relax the internal sphincter when excrement in the rectum induces defecation. Find a toilet to empty your external sphincter.

People mentally divide the large intestine because there is no real division. They may call it the colon but mean the cecum, colon, and rectum. The colon, including the cecum, is considered here.

The large intestine is only about six feet long, compared to the small intestine's length of 22 feet. The big intestine is so named because it is broader — roughly three inches — than the small intestine, which is just one inch in diameter.

The intestine can contract in different ways for separating layers of circular and longitudinal muscles. The mucous lining contains blood vessels, nerve endings, and glands that secrete and absorb substances.

• Diverticulitis: Diverticulitis is an inflammation of the small pouches that line the parts of the intestine. Stomach pain, bloating, constipation, and diarrhoea can result. Inflammation can cause life-threatening infections. and Removing the damaged intestine may require surgery.
• Ulcerative Colitis: It is an inflammatory bowel disease (IBD) that causes digestive tract inflammation and ulcers (sores). Ulcerative colitis affects the lining of your large intestine, also known as the colon, and the rectum.
• Microscopic Colitis: It causes colon lining inflammation, abdominal pain, and loose stools. Microscopic colitis has no cure, but treatments can manage symptoms.
• Pseudomembranous colitis: Pseudomembranous colitis causes colon inflammation and pus. This might induce severe stomach pain and diarrhoea. Infection and drugs can cause the illness. Antibiotics treat.
• Proctitis: Proctitis is rectum-anus inflammation Loose stools, rectal bleeding, and itching are other symptoms. Bacterial, viral, inflammatory bowel, and radiation therapy can cause proctitis. ц Medication and lifestyle changes usually treat proctitis.
• Necrotizing Enterocolitis: Necrotizing enterocolitis (NEC) is a serious problem that can happen when a baby is in a situation of pre-term pregnancy. It most often happens to babies born before 28 weeks, but it can also happen to full-term babies. NEC usually starts within the first two weeks of a baby's life.
• Malrotation: The large intestine rotates improperly in malrotation. and Untreated, it can kill.
• Crohn’s Disease: Crohn's disease, an inflammatory bowel disease, can affect the digestive tract from start of the GIT to the end. Crohn's disease is incurable, but treatment can reduce symptoms and improve quality of life.
• Rectal Ulcers: Rectal ulcers are defined as sores or breaks in the lining of the rectum. They are often accompanied by symptoms such as pain in the abdomen, loose stools, and vomiting. In some cases, rectal ulcers can also lead to bleeding from the anus.
• Haemorrhoids: Haemorrhoids are enlarged blood vessel-containing lumps or masses of tissue in the anus and rectum. They resemble varicose veins in the legs. Haemorrhoids frequently cause discomfort and severe bleeding.
• Colorectal Polyps: A colorectal polyp is a small growth that protrudes from the colon or rectum lining. These tumours are usually benign, which means they are not cancerous. However, some polyps can progress to cancer over time.
• Colorectal Cancer: A colon or rectum polyp is a tiny development. These tumours are typically benign. Some polyps can become cancerous.
• Hirschsprung Disease: Hirschsprung disease is a large intestine disorder that affects bowel movements. Other symptoms include bleeding, constipation, and loose stools. Lack of large intestine nerve cells causes Hirschsprung disease. ц
• Large Bowel Obstruction: Stool is blocked by a significant intestinal obstruction. Abdominal discomfort, diarrhoea, and bleeding are frequent symptoms. Untreated big intestinal obstructions can kill. Treatment often entails surgery to remove the obstruction.
• Intestinal Ischemic Syndrome: Pain in the belly and diarrhoea are symptoms of intestinal pseudo-obstruction. Also, it raises the risk of bleeding. A bowel obstruction is the root of the problem.
• Rectal Bleeding: Any loss of blood from the anus is considered rectal bleeding. From a trace of blood on the toilet paper to a significant amount of blood in the faeces, this is a common occurrence.
• Rectal Prolapse: When the rectum moves outside within the pelvic region and protrudes through the anus, this is known as rectal prolapse. Pain, bleeding, and diarrhoea are all possible side effects of this condition. Sometimes, surgical intervention is the only option for resolving the issue at hand.
• Rectocele: When the rectum protrudes through the vaginal wall, this is known as a rectocele. Abdominal pain, diarrhoea, and even internal bleeding can result from this. Rectoceles can be embarrassing, and in some cases they can make it hard to urinate or have a bowel movement.
• Pelvic Floor Dysfunction: The peritoneal organs known as bladder, uterus, and rectum are supported by the muscles of pelvic floor. Surgery, childbirth, and other circumstances can weaken or injure these muscles. If this happens, they may not be able to support the organs, causing discomfort and other issues.
• Anal Fistula: Anal fistulas are small tunnels between the skin and muscle around the anus in Surgery drains the infection and closes an anal fistula.
• Constipation: Constipation causes abdominal pain and bowel obstruction. Constipation can cause loose stools or bleeding. Low-fibre or fluid diets often cause constipation. and
• Faecal Incontinence: Stool incontinence is involuntary Abdominal pain, diarrhoea, and bleeding are symptoms. Dietary changes, medications, or surgery may treat the underlying cause.
• Irritable Bowel Syndrome (IBS): The exact cause of IBS is unknown, but it is thought to be related to an imbalance in the digestive system. Many people don't seek treatment for IBS because they're ashamed. IBS therapy improves quality of life.
• Obstructed Defecation: Obstructed defecation causes abdominal pain and loose, sometimes bloody stools. Obstructions in the intestine, rectum, or anal canal can cause this. Constipation—caused by a lack of fibre, water, or medications—is the most common cause of obstructed defecation.
• Anismus: Anismus is a condition that is characterised by pain in the abdomen and loose stools. In some cases, there may be bleeding from the rectum. The cause of this condition is unknown, but it is thought to be related to a dysfunction of the anal sphincter muscles.
• Paralytic Ileus: Paralytic ileus is a condition characterised by pain in the abdomen and either constipation or loose stools.

• Barium enema: An X-ray procedure used to visualise the large intestine is a barium enema. The procedure entails inserting a small tube into the rectum and filling the large intestine with barium, a chalky liquid that makes the intestines visible on an X-ray.
• Flexible sigmoidoscopy: A flexible sigmoidoscopy is a diagnostic procedure that employs a long, thin, flexible tube with a small camera and light at its end.
• Proctoscopy: A flexible sigmoidoscopy is a test that uses a long, thin, flexible tube with a tiny camera and light on the end of it.The tube is inserted into your rectum and up through your sigmoid colon — the last part of your large intestine before your rectum.
• Colonoscopy: A colonoscopy is a medical procedure during which a doctor inserts a long, flexible tube into the rectum and colon in order to examine the inside of the large intestine. The procedure is used to detect problems such as bleeding, inflammation, or polyps
• Virtual colonoscopy: A virtual colonoscopy is a test that uses CT scan images to look for problems in the colon. The test is used to check for things like inflammation, polyps, or tumours. It is also used to find the cause of symptoms like pain in the abdomen, loose stools, or bleeding.
• Anorectal manometry: Anorectal manometry is a medical procedure that assesses the function of the anal sphincter muscles and the rectum. The test is used to help diagnose conditions such as faecal incontinence, constipation, and obstructed defecation. It can also be used to determine the cause of pain in the abdomen or rectum, or bleeding from the anus.
• Endoscopic ultrasound: A medical procedure called an endoscopic ultrasound is used to see inside the digestive system. The mouth and throat are used to insert the endoscope.
• Urea breath test: A urea breath test is a simple and noninvasive test used to diagnose Helicobacter pylori (H. pylori) infection. The test is performed by measuring the amount of urea in your breath before and after you drink a solution containing urea.
• Hydrogen breath test: Lactose intolerance and SIBO are diagnosed with a hydrogen breath test (SIBO). The patient drinks a sugar solution, usually lactose or glucose, and breathes into a tube connected to a hydrogen-measuring machine.
• Defecography: A defecography is a type of medical imaging test that is used to assess how well the rectum and anus are working. The test is also known as anorectal manometry.
• Colonic transit test: A colonic transit test is a diagnostic procedure used to assess how well the muscles of the large intestine are working. The test involves eating a meal that contains a marker, such as cooked rice, and then tracking the movement of the marker through the intestine over the course of several days.
• Stool test: Stool tests detect gastrointestinal diseases and disorders. Doctors may order the test for abdominal pain, loose stools, or bleeding.

• Transanal endoscopic microsurgery: Transanal endoscopic microsurgery treats rectum and anus problems minimally. [ Transanal endoscopic microsurgery treats inflammatory bowel illness, bleeding, and abdominal or rectum pain.
• Laparoscopic rectopexy: Laparoscopy is a surgical procedure in which the physician must gain access to the inside of the belly and pelvis without creating significant incisions or skin cuts. This is also known as minimally invasive surgery or keyhole surgery for the treatment of the large intestine.
• Rectocele repair: Rectocele is a vaginal rectum bulge. Incontinence and bowel obstruction may result. when. This supports the rectum and prevents vaginal bulging.
• Laparoscopic abdominoperineal resection: Laparoscopic abdominoperineal resections (APRs) treat rectal cancer. The surgeon removes the rectum and anus through minor abdominal incisions. Early-stage rectal cancer patients usually undergo this operation.
• Colectomy: A colectomy is a surgical procedure in which the colon, or a portion of the colon, is removed. A colectomy can be performed as an open surgery or laparoscopic surgery.
• Colostomy: A colostomy may be necessary if there is a blockage in the colon that cannot be removed surgically. This may be due to cancer, Crohn's disease, or another condition. A colostomy may also be needed if the rectum or anus needs to be removed.

• Steroids for reducing inflammation of the large intestine: Steroids are commonly administered via tablet or injection. They can be used to treat acute episodes of inflammation or to prevent flare-ups on a long-term basis.
• Analgesics for pain in the large intestine: To treat stiffness in the large intestine, a variety of muscle relaxants are available. Antispasmodics, which reduce spasm symptoms, and anti-inflammatories, which reduce inflammation in the colon, are the most common and effective treatments.
• Muscle relaxants for stiffness in the large intestine: There are numerous types of muscle relaxants available for the treatment of large intestine stiffness. The most prevalent and successful treatments are antispasmodics, which decrease the signs of spasms, and anti-inflammatories, which reduce colon inflammation.
• Antibiotics for infection in the large intestine: There are a variety of antibiotics available for the treatment of large intestine infections. Amoxicillin, ciprofloxacin, and levofloxacin are the most prevalent.
• Nutritional supplements for reducing pain in the large intestine: Curcumin is a common supplement that is derived from the spice turmeric. Omega-3 fatty acids, which have also been shown to have anti-inflammatory effects, may also be beneficial.
• Antivirals for treating infection of the large intestine: Antivirals such as lopinavir/ritonavir, sofosbuvir/velpatasvir, and daclatasvir are frequently employed to treat this type of infection.
• Chemotherapeutic medicines for the large intestine: These drugs may treat cancer or its symptoms. 5-fluorouracil, capecitabine, and irinotecan are the most common large intestine cancer chemotherapies.