Ischemic colitis is the name given to inflammation of the large intestine (colon) caused by decreased blood flow to the colon. Ischemic colitis can happen in any part of the colon but is most common on the left side of the colon as a result of the blood distribution to that side of the colon. The symptoms of ischemic colitis include abdominal pain, bloody diarrhea, and having to defecate urgently. Ischemic colitis is most often caused by a small blood clot in the arteries which supply blood to the colon. Over time, you can also have slower onset ischemic colitis as a result of atherosclerosis (cholesterol plaque buildup in the arteries). Additional medical causes of ischemic colitis include vasculitis (inflammation of the blood vessels due to another disease), hernia (protrusion of an organ or bowel into a space where it does not normally belong), diabetes, previous radiation of the abdomen, colon cancer, certain infections and previous abdominal surgery. Certain medications may rarely cause ischemic colitis. Risk factors include older age, smoking, high blood pressure, high cholesterol, heart failure, and low blood pressure (especially if related to shock). Sometimes ischemic colitis will resolve on its own, but may also become more serious and severe. Complications of ischemic colitis can include gangrene (death of the tissue of the colon), bleeding, perforation (a hole in the colon, which can lead to serious abdominal infections), scarring of the colon, and may even be the first sign of colon cancer.
Abdominal pain, cramping, fever, bloody stool, urgency to evacuate the bowels, nausea, vomiting, diarrhea, weight loss over time
After taking a history and examining your abdomen, your doctor will want to do some additional testing. Your doctor will likely check your blood for a high white blood cell count, which is often a sign of infection. Your stool may also be checked for signs of blood or infection that can be confused with ischemic colitis. You may see a gastroenterologist for a procedure called a colonoscopy. The colonoscopy involves placing a thin tube with a camera at the end into the rectum while you are under anesthesia to look at the colon. If anything looks abnormal, you doctor can take biopsies (small samples) of the tissue to look at under a microscope to see what might be causing your symptoms. Your doctor may want to repeat your colonoscopy when your symptoms go away and the inflammation in the colon should be gone. Your doctor may also recommend x-rays of the abdomen after injecting barium into the rectum to look for abnormalities. To look at the arteries leading to your colon, your doctor may inject dye into your veins and take x-rays to see where the arteries may not be flowing normally. Your doctor may also want a CT scan or MRI picture of your body.
Treatment for ischemic colitis depends on whether your symptoms are mild or severe. A lot of the time, ischemic colitis is handled in the hospital environment. With mild colitis, your doctor may give you antibiotics and medications to keep your blood pressure at a good level to keep the blood flowing to our colon. Your doctor may also want you to take an aspirin to keep more of your blood from clotting. Your doctor may recommend IV fluids and resting your bowels by not eating for a couple of days. Your symptoms may go away in a day or two. Your doctor will try to figure out if you have a condition that causes clots and if that condition needs to be treated. More severe cases of ischemic colitis, where the bowel has died or become gangrenous, may require surgery to remove the dead part of your bowel (bowel resection). You are more likely to need surgery if you abdominal pain is persistent, you have bleeding ulcers, your colon has a hole or perforation, or gangrene. For any of these more serious conditions, you will be in the hospital with IV antibiotics and be closely monitored while you heal.