What is inflammatory bowel disease?
7/11/2024 by Laura Kek, M.D., M.S.
What is inflammatory bowel disease (IBD)?
IBD is a chronic, inflammatory illness involving the digestive tract. It's an umbrella term that describes two specific conditions — ulcerative colitis and Crohn's disease.
These conditions differ by the locations affected, their associated risks and complications, and their treatment protocols. They are both autoimmune diseases, meaning the body mistakenly injures healthy tissue, causing problems.
Ulcerative Colitis can involve the large intestine, or colon, and rectum. Usually, the inflammation seen is continuous and causes ulcerations.
Crohn's disease can involve any part of the gastrointestinal tract (GI), including the upper GI tract, small intestine and colon. The inflammation caused by Crohn's can skip around different portions of the GI tract, causing intermittent areas of damage.
Some individuals with IBD may have mild disease that does not require treatment, but others may need medications and surgery.
What are the symptoms of IBD?
- Diarrhea.
- Abdominal pain.
- Bloody stool.
- Weight loss.
- Fatigue.
- Fevers.
- Anemia or a low blood count.
Symptoms of IBD can often come in "flares," which refers to episodes of the symptoms mentioned above.
Everyone's bowel habits are different, but it's important to see your clinician if you experience new and persistent changes.
What causes IBD?
While the exact cause of IBD is unknown, there is research ongoing to determine what specific causes can be found.
Initially, there was some thought that diet and stress caused IBD. However, while certain factors can exacerbate the severity and frequency of flares, diet and stress are not causes of IBD.
What increases my risk of getting IBD?
- Family history — having close relatives with IBD can put you at higher risk.
- Race or Ethnicity — while any race or ethnic group can get IBD, those who are White, of European descent, or Ashkenazi Jewish may have a higher risk.
- Smoking — cigarette smoking increases the risk of Crohn's disease, but it's interestingly protective against ulcerative colitis. Smoking is very harmful to your body and overall health, so the benefit of avoiding cigarettes outweighs any preventive advantage.
Complications
IBD increases the risk of colon cancer. Regular screening usually begins 8 to 10 years after diagnosis, but your clinician will help decide the best screening interval for you.
Despite being a gastrointestinal illness, IBD can affect the entire body and cause problems in different organ systems:
- Eye inflammation such as uveitis or scleritis.
- Skin inflammation in the form of pyoderma gangrenosum, erythema nodosum and oral ulcers.
- Joint inflammation or arthritis.
- Blood clots and vasculitis.
- Liver and biliary systems such as primary sclerosing cholangitis and fatty liver.
Untreated or undertreated IBD can also cause inflammatory damage to the GI tract over time, resulting in:
- Bowel obstruction from narrowing in the gut wall, which can block intestinal movement.
- Fistulas, which are abnormal connections between two parts of the body, such as the colon and the bladder.
- Abscesses, which are pockets of infection that usually require draining.
Some of the complications of IBD are independent of disease activity, meaning they can happen even if your illness is very well-controlled. It's important to pay attention to changes and communicate any new symptoms to your clinician.
How IBD is diagnosed: A thorough history and physical exam should always be the first step in evaluation.
Laboratory testing: Blood tests to check for anemia (low blood count), evidence of infection, or other IBD-associated markers, such as ASCA. Stool tests to evaluate for evidence of infection or inflammation.
Procedures:
- Colonoscopy — a tube with a camera allows visualization of the colon. Small pieces are removed for biopsy, which is the definitive way to diagnose IBD.
- Upper endoscopy — a tube with a camera allows visualization of the esophagus, stomach and first portion of the small intestine. Biopsies are also taken for evaluation.
- Capsule endoscopy — a capsule with a camera inside is swallowed to allow for visualization of the small intestine
Imaging: X-ray, CT scan or MRI.
Not all testing mentioned above is always done to diagnose IBD. Other, more specialized tests may be needed if your diagnosis is uncertain. Your clinician will decide which test is best for you.
How is IBD treated?
There is no cure for IBD, so the goal of treatment is to control flares, minimize intestinal damage and control symptoms occurring in other parts of the body. This may involve medications, surgeries and evaluations by other specialists.
Multiple categories of medication can help with immune system suppression, pain and diarrhea. It's important to take these medications as prescribed and continue to take them until directed otherwise.
Sometimes, medical therapy is not enough to control symptoms and surgery may be required to remove the affected portion of the gut. This can result in the formation of a stoma, which is when the remaining portion of the intestine empties into a bag on the outside of the abdomen.
Your clinician will help choose the best treatment regimen for you based on your condition's unique characteristics.
Laura Kek, M.D., M.S., is a resident physician at Mayo Clinic in Rochester, Minnesota. She earned her medical degree and Master of Biomedical Sciences at Rosalind Franklin University of Medicine and Science in North Chicago, Illinois. She is interested in gastrointestinal health and patient education.