Ischemic colitis occurs when there is not enough blood flowing to the colon, also known as the large intestine. It is more likely to occur in people who are over 60, smoke cigarettes, or have diabetes.
Ischemic colitis is the most common type of gut-based ischemia, accounting for 1 in every 2,000 hospital admissions.
Symptoms of ischemic colitis include pain, tenderness, and digestive problems. It is often mistaken for irritable bowel disease (IBD) or other gastrointestinal issues.
The condition can develop over time (chronic) or come on suddenly (acute). Sometimes, chronic ischemic colitis can heal on its own, but some people may still need treatment to prevent infection or colon damage.
Ischemic colitis that comes on suddenly is considered a medical emergency and requires urgent care.
This article describes the causes and symptoms of ischemic colitis, along with the available treatment options.
The most typical symptom of ischemic colitis is stomach cramping and pain. The pain may be mild or moderate, and it often occurs suddenly. Typically, pain occurs on the left side of the abdomen.
Other symptoms of ischemic colitis include:
- stomach pain after meals
- tenderness in the stomach
- an urgent need to pass stool
The risk of complications is higher when symptoms develop on the right side of the stomach, and pain in this area may be more severe as well. Pain on the right side suggests a blockage in the arteries leading to the small intestine as well as the colon.
A lack of blood flow to the colon causes ischemic colitis. This lack of blood flow (ischemia) can occur for many reasons.
Other factors that contribute to ischemic colitis include:
- blood clots in the arteries leading to the intestines
- severely low blood pressure (hypotension)
- bowel obstructions due to scar tissue, tumors, or hernias
- conditions that affect the blood, including vasculitis and sickle cell anemia
- surgical procedures that involve the heart, blood vessels, colon, or surrounding areas
- use of cocaine or methamphetamines
- colon cancer, in rare cases
Rarely, medications can cause ischemic colitis, including:
Certain factors increase a person’s chance of developing ischemic colitis. These include:
Age. Adults over the age of 60 are most at risk, possibly because arteries tend to harden with age.
Clotting abnormalities. Disorders such as Factor V Leiden increase the risk of blood clots.
Other medical conditions. Diabetes, congestive heart failure, and low blood pressure all increase the risk of ischemic colitis.
Prior surgery. People who have previously had surgery involving the aorta or abdomen are at higher risk than others of developing ischemic colitis.
Heavy exercise. Engaging in strenuous activities, such as running a marathon, can limit blood flow to the colon.
Treatment for ischemic colitis depends on its severity.
Mild cases may resolve within a few days. If treatments are required, they include:
- antibiotics, to prevent infection
- a liquid diet
- intravenous fluids, to prevent dehydration
- medication for pain relief
Other ways to manage the condition include:
- treating underlying medical conditions, including diabetes and congestive heart failure
- avoiding medications that cause vasoconstriction (narrowing of the blood vessels)
Acute ischemic colitis is a medical emergency. Treatments include medications such as thrombolytic drugs for blood clots or vasodilators to widen narrow arteries.
Typically, follow-up colonoscopies are performed to check for healing and complications.
Severe ischemic colitis that does not respond to other treatments may require surgery. An estimated 20 percent of people with the condition will need some form of surgical intervention.
Those with underlying medical conditions are more likely to need surgery.
Surgeons may operate to:
- repair damage to the colon
- bypass a blockage in the mesenteric arteries
- remove scar tissue
Ischemic colitis shares symptoms with other digestive disorders, particularly inflammatory bowel diseases, which include Crohn’s disease and ulcerative colitis. This can make diagnosis more complicated.
After taking a medical history, a doctor may order imaging tests to confirm a diagnosis and rule out other conditions. Imaging tests used to diagnose ischemic colitis include:
- Ultrasound or abdominal CT scan. Both ultrasound and CT scans allow doctors to see images of the colon and intestines.
- Mesenteric angiogram. A mesenteric angiogram test uses X-rays to detect blockages inside the arteries that supply the intestines with blood.
Other diagnostic tests include:
- Blood test. If a blood test shows a high white blood cell count, it suggests acute ischemic colitis.
- Stool analysis. A stool sample can help identify if an infection is causing the symptoms.
- Colonoscopy. A colonoscopy involves inserting a flexible tube into the rectum to the colon. The tube has a light and a camera that allow the doctor to see images of the colon.
The most serious complication of ischemic colitis is gangrene (tissue death). Gangrene results from a loss of blood flow to the tissue and can be life-threatening. People who experience gangrene need surgery to remove the blockage and damaged tissue.
Other complications include:
Most people with chronic ischemic colitis recover with medication, and those experiencing severe ischemic colitis can have surgery. People may need to make some lifestyle changes to prevent the condition from returning.
Examples of helpful lifestyle changes include quitting smoking, exercising regularly, and eating a balanced diet. People may need to stop taking medications that contribute to ischemic colitis, with a doctor’s advice.
Acute ischemic colitis has a poorer outlook and a higher mortality rate than chronic ischemic colitis because it often causes gangrene. Swift medical treatment is crucial in acute cases.
People who experience symptoms of ischemic colitis should see a doctor promptly to improve the outlook and reduce the risk of complications. People should not ignore bloody stools. Seek emergency medical attention for severe abdominal pain that makes it difficult to sit down or get comfortable.