Diversion Colitis

Diversion colitis is inflammation of a part of your colon that no longer has stool passing through it. This inflammation is usually a side effect of colostomy surgery. A colostomy redirects your colon to an opening in your abdominal wall called a stoma.^1,2

You may have a colostomy after another type of surgery called a colectomy. In a colectomy, a surgeon removes part or all of your colon. Colectomy is 1 treatment option for severe inflammatory bowel disease (IBD).^1,2

What causes diversion colitis?

When doctors divert part of the colon, it no longer gets the regular flow of stool needed to stay healthy. This lack of activity and nutrients from stool can lead to inflammation, which is your body's response to injury or irritation. The diverted section of the colon also has fewer helpful bacteria, which can negatively affect your colon’s health.^1,3

Who is most likely to get diversion colitis?

Diversion colitis happens most often in people with IBD who have had a colostomy. But you can get it after a colostomy for other conditions that affect the digestive tract, too. These conditions include cancer or infections.^2,3

Types of diversion colitis

There are a few forms of the diversion colitis, each triggered by different things:³

• Diversion colitis – This condition happens in parts of the bowel that doctors divert during a colostomy or similar procedure called an ileostomy.
• Diversion pouchitis – This type of diversion colitis happens after a surgery called ileal pouch-anal anastomosis (IPAA). Doctors perform this surgery on people with ulcerative colitis. They use part of the small intestine to create a pouch connected to your anus. When stool diverts away from the pouch, it can cause inflammation.
• Collagenous ileitis – This rare condition involves inflammation with collagen buildup in the small intestine. It happens in people with certain types of cancer.
• Diversion neovaginitis – This condition happens in people who have had vaginal reconstruction using the last part of the colon (sigmoid colon).

What are the symptoms of diversion colitis?

Most people with diversion colitis do not show symptoms. But if they do, the symptoms can seriously impact their quality of life. Common symptoms of diversion colitis include:³

• The feeling of still needing to pass stool after you have tried to go (tenesmus)
• Frequent urgency to use the bathroom
• Bloody or mucus discharge
• Stomach pain
• Pelvic pain or pressure

Many people with diversion colitis have mild symptoms. But sometimes, they may have severe symptoms like heavy bleeding or diarrhea. In rare cases, they may develop sepsis, which is a state of whole-body shock in reaction to an infection. Symptoms typically start 3 months to 3 years after a colostomy or other diversion surgery.³

How do doctors diagnose diversion colitis?

Your doctor will first want to know more about your symptoms, including when they started. After performing a physical exam, they may run tests that include:¹

• Blood tests
• Stool tests
• A colonoscopy or flexible sigmoidoscopy – These tests allow doctors to see the inside of your colon and take tissue samples (biopsies).

What are the treatments for diversion colitis?

The best way to manage diversion colitis is to surgically reverse the stoma. This reconnects the intestines so that stool can pass through them normally again. If you cannot have this surgery, medicines such as corticosteroids or 5-aminosalicylic acid can help reduce inflammation. Short-chain fatty acids may help maintain overall colon health.⁴