Crohn’s Disease vs. Ulcerative Colitis: What’s the Difference?

“Crohn’s disease and ulcerative colitis cause life-disrupting symptoms like stomach cramps, diarrhea, weight loss, and decreased appetite,” said Isaiah Schuster, MD, Catholic Health Physician Partners Gastroenterologist. “While the two inflammatory bowel diseases are alike in many ways, there are key differences.”

Dr. Schuster noted there is no cure for Crohn’s disease or ulcerative colitis, but medication, lifestyle changes and surgery can manage symptoms and help make everyday activities easier to enjoy.

“Call your physician if you are concerned that you are exhibiting symptoms,” said Dr. Schuster.

How are Crohn’s disease and colitis similar?

Both Crohn’s disease and ulcerative colitis are types of inflammatory bowel disease (IBD). Each causes the lining of the gastrointestinal (GI) tract to become inflamed. The inflammation is triggered by an autoimmune response, meaning the body’s immune mistakenly attacks the healthy intestine. Doctors do not fully understand why this happens but suspect a genetic or environmental connection.

Crohn’s and ulcerative colitis are chronic diseases.

“People with either disease fluctuate between periods of active disease, called flares, and periods when inflammation decreases, called remission,” said Dr. Schuster. “Digesting food, absorbing nutrients, or healthily eliminating waste during a flare is difficult.”

Symptoms of both diseases include:

Abdominal pain and cramps, often severe
Anemia
Constipation
Diarrhea, possibly bloody
Fatigue
Fever
Loss of appetite
Rectal bleeding
Sores in the mouth and around the anus (Crohn’s disease only)
Weight loss and malnutrition

What is Crohn’s disease?

Crohn’s disease is named for the doctor who identified the condition in 1932. Crohn’s inflammation can happen anywhere along the digestive tract, from the mouth to the anus. Most people experience inflammation in the lower section of the small intestine or upper part of the large intestine (colon).

Inflammation often occurs in patches throughout the intestine and penetrates from the inner to outer lining. It can also affect the tissues that connect the small intestine to the abdominal wall or cause symptoms not related to the intestine, including:

Abnormal connections between two body parts called fistulas
Bile duct inflammation
Colitic arthritis that moves along the body, impacting the knees, ankles, hips, wrists and elbows
Kidney stones
Urinary tract complications

What is ulcerative colitis?

Ulcerative colitis is named for the small sores, or ulcers, that form in the lower intestine. The ulcers usually begin at the rectum and move upward through the colon uniformly. Unlike Crohn’s disease, ulcerative colitis affects only the inner layer of the intestine, and the inflammation doesn’t spread outside the colon.

How is Crohn’s disease and colitis diagnosed?

To diagnose these conditions, a gastroenterologist or digestive system specialist looks inside the intestine to find out where the inflammation occurs. Tests to examine the intestine include:

Contrast X-rays to see how fluid moves through your digestive system
CT scans and MRIs to rule out conditions with similar symptoms
Endoscopy, such as a colonoscopy, uses a tiny camera to see inside your digestive system
X-rays to see where the intestine is blocked or narrow

Doctors may also look for specific blood antibodies to make a diagnosis.

How is Crohn’s disease and colitis treated?

While there’s no cure for these conditions, treatment is available.

“Lifestyle changes, such as dietary changes, quitting smoking, regular exercise, and stress management, can help,” said Dr. Schuster. “Additionally, medications like antibiotics, immunosuppressants, steroids and others can help keep IBD under control.”

With medication and lifestyle modifications, complete remission of ulcerative colitis is possible. Complete remission is less common with Crohn’s disease. Surgical removal of the entire colon or the affected portions of the intestine is often necessary for long-term symptom relief.

Your doctor will discuss the best options for you.