Ischemic colitis (IC) is an inflammatory condition of the large intestine, or colon. It develops when there isn’t enough blood flow to the colon. IC can occur at any age, but it’s most common among those over the age of 60.
A buildup of plaque inside the arteries (atherosclerosis) can cause chronic, or long-term, IC. This condition may also go away with mild treatment, such as a short-term liquid diet and antibiotics.
IC is also known as mesenteric artery ischemia, mesenteric vascular disease, or colonic ischemia. A blood clot usually causes acute (sudden and short-term) IC. Acute IC is a medical emergency and requires treatment quickly. The mortality rate is high if gangrene, or death of tissue, occurs in the colon.
IC occurs when there’s a lack of blood flow to your colon. The hardening of one or more of the mesenteric arteries may cause a sudden reduction in blood flow, which is also called an infarction. These are the arteries that supply blood to your intestines. The arteries can harden when there’s a buildup of fatty deposits called plaque inside your artery walls. This condition is known as atherosclerosis. It’s a common cause of IC among people who have a history of coronary artery disease or peripheral vascular disease.
A blood clot can also block the mesenteric arteries and stop or reduce blood flow. Clots are more common in people with an irregular heartbeat, or arrhythmia.
IC most often occurs in people who are over 60 years old. This may be because arteries tend to harden as you get older. As you age, your heart and blood vessels need to work harder to pump and receive blood. This causes your arteries to weaken, making them more prone to plaque buildup.
You also have a higher risk of developing IC if you:
- have congestive heart failure
- have diabetes
- have low blood pressure
- have a history of surgical procedures to the aorta
- take medications that can cause constipation
Most people with IC feel mild to moderate abdominal pain. This pain often occurs suddenly and feels like a stomach cramp. Some blood may also be present in the stool, but the bleeding shouldn’t be severe. Excessive blood in the stool may be a sign of a different problem, such as colon cancer, or an inflammatory bowel disease like Crohn’s disease.
Other symptoms include:
IC can be hard to diagnose. It can easily be mistaken for inflammatory bowel disease, a group of diseases that includes Crohn’s disease and ulcerative colitis.
Your doctor will ask you about your medical history and order several diagnostic tests. These tests can include the following:
- An ultrasound or CT scan can create images of your blood vessels and intestines.
- A mesenteric angiogram is an imaging test that uses X-rays to see inside your arteries and determine the location of the blockage.
- A blood test can check for a white blood cell count. If your white blood cell count is high, it may indicate acute IC.
Mild cases of IC are often treated with:
- antibiotics (to prevent infection)
- a liquid diet
- intravenous (IV) fluids (for hydration)
- pain medication
Acute IC is a medical emergency. It may require:
- thrombolytics, which are medicines that dissolve blot clots
- vasodilators, which are medicines that can widen your mesenteric arteries
- surgery to remove the blockage in your arteries
People with chronic IC usually only need surgery if other treatments fail.
The most dangerous complication of IC is gangrene, or tissue death. When blood flow to your colon is limited, the tissue can die. If this occurs, you may require surgery to remove the dead tissue.
Other complications associated with IC include:
- a perforation, or hole, in your intestine
- peritonitis, which is an inflammation of the tissue lining your abdomen
- sepsis, which is a very serious and widespread bacterial infection
Most people with chronic IC can be successfully treated with medication and surgery. However, the problem may come back if you don’t maintain a healthy lifestyle. Your arteries will continue to harden if certain lifestyle changes aren’t made. These changes may include exercising more frequently or quitting smoking.
The outlook for people with acute IC is often poor because tissue death in the intestine frequently occurs before surgery. The outlook is much better if you receive a diagnosis and start treatment right away.
A healthy lifestyle can reduce your risk of developing hardened arteries. The basics of a healthy lifestyle include:
- exercising regularly
- eating a healthy diet
- treating heart conditions that can lead to blood clots, such as an irregular heartbeat
- monitoring your blood cholesterol and blood pressure
- not smoking
Your doctor may also recommend that you stop taking any medication that can cause ischemic colitis. These drugs can include certain antibiotics or heart and migraine medications. Make sure you tell your doctor what medications you’re currently taking.