The small intestine, which is also called small bowel, is the section of the gastrointestinal tract that is located between the stomach and the large intestine. The small intestine comprises duodenum, jejunum, and ileum. Though it is called small intestine, it is actually the largest part of the digestive tract. The length of the small intestine in adults is around 6 meters. Though the large intestine is about 1.5 meters long, it is called so due to its width. While the small intestine is around 2.5 to 3.5 cm wide, the diameter of the large intestine is about 10 cm. Small bowel performs vital functions involving digestion of food and absorption of essential nutrients from the food into the body. There are a number of diseases that can affect the function of the small bowel in an adverse manner.
Diseases that Affect the Small Intestine
A perforated bowel, which is also known as intestinal perforation, is a condition that can affect the small as well as the large intestine. It is characterized by the presence of a perforation or a hole in the intestine.
Causes: This condition can result from trauma to the intestine during a surgery. Perforation could also occur during procedures such as enema or colonoscopy. Swallowing a sharp object can also result in an injury. Medical conditions that can make a person susceptible to this condition include appendicitis, Crohn's disease, ulcerative colitis, diverticulitis, roundworm infestation, or cancer.
Symptoms: Abdominal pain, vomiting, blood in stool, nausea and other bowel problems are some of the common symptoms of this condition. If left untreated, the affected individual could suffer from sepsis or a blood infection.
Treatment: Complications can occur when the contents of the intestine spill over from the perforation into the abdomen. The treatment of this condition involves repairing the perforation through surgery.
Small Intestine Cancer
Cancer is a serious medical condition that is characterized by development of a tumor due to abnormal and uncontrolled cell division. Small bowel cancer is rare when compared to other cancers of the gastrointestinal tract. There are five types of cancer that can affect the small bowel. These include adenocarcinoma, gastrointestinal stromal tumor, lymphoma, sarcoma, and carcinoid tumors.
Causes: The cause of the cancer of the small intestine is unknown, but it is believed that certain conditions can put a person at an increased risk of developing small bowel cancer. These include celiac disease, Crohn's disease, colon cancer, cancer of the rectum, familial adenomatous polyposis, hereditary non-polyposis colorectal cancer, and Peutz-Jegher's syndrome. Men are more likely to developing small intestine cancer.
Symptoms: The symptoms include severe pain in the central abdominal area, lumps in the abdomen, sudden weight loss and blood in stool.
Treatment: The treatment includes chemotherapy and radiation therapy. Surgical removal of the affected part of the intestine may be recommended. However, surgery is recommended only after examining the stage of the cancer and the severity of the condition.
Celiac disease, also known as celiac sprue or non-tropical sprue, is a medical condition that is characterized by damaged small intestine lining.
Causes: The damage to the small fingerlike protrusions that line the small bowel is actually an immune response to consumption of food that contains gluten. When the villi get damaged, the absorption of nutrients is adversely affected. This is a genetic disorder that can be triggered by surgery, viral infections, pregnancy, and extreme stress. It may also be accompanied by other medical conditions such as type 1 diabetes, autoimmune liver or thyroid disease, rheumatoid arthritis, Addison's disease, and Sjögren's syndrome.
Symptoms: Children affected by this condition are likely to experience severe abdominal pain, bloating, constipation, nausea, vomiting and sudden weight loss. In adults, the symptoms include joint pain, seizures, fatigue and anemia. Irregularities in menstrual cycle could be experienced by women who suffer from celiac disease.
Treatment: The only treatment option for celiac disease is following a gluten-free diet so as to prevent the immune response.
Inflammatory Bowel Disease
The term 'inflammatory bowel disease' refers to a group of conditions that are characterized by inflammation of the mucosal lining of the small or the large intestine. Crohn's disease and ulcerative colitis are forms of inflammatory bowel disease. Any part of the digestive tract can be affected by Crohn's disease. On the other hand, ulcerative colitis usually affects the large intestine and the rectum. In rare cases, inflammation could occur in the ileum, which is lowest section of the small intestine.
Causes: The exact cause of these conditions is unknown, but it is believed that genetic and immunological factors may trigger the inflammatory response. It is believed that exposure to an infectious agent could also trigger inflammation of the mucosa.
Symptoms: The symptoms of these conditions include abdominal pain, cramps, diarrhea, loss of appetite, and weight loss.
Treatment: The treatment involves the use of anti-inflammatory drugs. In severe cases, surgery may be recommended.
Small Bowel Overgrowth Syndrome
Both the small and large intestine contain certain strains of bacteria. A person is diagnosed with small bowel bacterial overgrowth when these bacteria are present in abnormally large numbers in the small intestine.
Causes: Certain medical conditions can put a person at a greater risk of developing SBBO. These include selective IgA deficiency, motility disorders, diabetes, intestinal obstruction, diverticulosis, and scleroderma.
Symptoms: A person who is suffering from this condition is likely to experience symptoms such as pain, a feeling of fullness, excessive gas, distended stomach, diarrhea, bloating, or abdominal cramps.
Treatment: For any condition where the causal organism is a bacterium, the treatment involves the use of antibiotics. Usually antibiotics such as levofloxacin, ciprofloxacin or rifaximin are prescribed for treating SBBO. It is also essential to treat the conditions that may be putting a person at a risk of developing SBBO.
Hernia is a medical condition that occurs when the contents of a body cavity bulge out from a weak spot or tear in the wall of that cavity. Inguinal hernia is a type of abdominal hernia that occurs when a part of the intestine protrudes through a tear or a weak spot in the abdominal wall.
Causes: Weak spots may form in the wall if a person often lifts heavy objects. Those who are obese are at a risk. Those who have to strain during bowel movement are also susceptible. In case of women, weak spots can form on the abdominal wall during pregnancy and childbirth.
Symptoms: The symptoms for this condition include groin pain, a feeling of pressure or heaviness in the groin, difficulty in passing stool, development of a lump in the groin, and intestinal blockage. The intensity of pain may increase when the affected individual bends, coughs, or laughs. Hernia that becomes trapped in the groin region is called incarcerated hernia. Strangulated hernia is a complication of hernia. It occurs when the blood supply is cut off to incarcerated hernia. It needs immediate medical attention.
Treatment: The treatment options include open hernia repair, hernioplasty, laparoscopic hernia repair, or bowel resection.
Small Bowel Obstruction
Mechanical or functional obstruction or blockage of the small intestine is a medical condition that prevents fluids, food, and gas from passing through the small intestine in a normal manner.
Causes: Hernia, Crohn's disease, tumor, adhesions (presence of fibrous bands of tissue), and volvulus (twisting of the intestine) are medical conditions that can put a person at a risk of developing small bowel obstruction. Paralytic ileus, which is also called pseudo-obstruction, refers to intestinal obstruction that occurs when the muscles of the intestine don't function properly. This is one of the common contributory factors for bowel obstruction in children.
Symptoms: The symptoms of intestinal obstruction include intermittent pain, cramping, abdominal swelling, constipation, bloating, and vomiting. Diarrhea could occur in case the small intestine is partially blocked.
Treatment: The treatment usually involves intravenous administration of fluids and drugs. The insertion of a nasogastric tube from the nose into the stomach helps to remove gas as well as fluids. This helps in alleviating symptoms such as bloating and abdominal swelling. In case of a complete blockage, surgery is often recommended for removal of the mechanical obstruction.
Besides the aforementioned conditions, congenital defects, mesenteric ischemia, mesenteric cysts, duodenal ulcers, diverticular disease, bacterial infections, viral infections, and diseases caused by infectious agents could also adversely affect the function of the small intestine.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.