Inflammatory Bowel Disease: Crohn's and Ulcerative Colitis

An Overview of Inflammatory Bowel Disease (IBD)

Ulcerative colitis and Crohn's disease are incurable chronic diseases of the intestinal tract. The two diseases are often grouped together as inflammatory bowel disease (IBD) because of their similar symptoms.

As many as 5 million people (including 1.6 million Americans, 23,000 Australians, and 250,000 Canadians) worldwide live with a form IBD. The cost of lost productivity to U.S. businesses due to IBD is estimated to be as much as $.8 billion a year.

Crohn's disease and ulcerative colitis are lifelong, chronic conditions, but there are effective treatments available. Medical and surgical advancements are occurring every year and most people with IBD achieve remission and are able to preserve their quality of life.

People diagnosed with IBD will need regular care from a digestive specialist—a gastroenterologist—and support from other healthcare providers such as a dietician/nutritionist, a primary care provider, or other specialists as the need arises.


The Most Important Things to Know


Crohn's disease and ulcerative colitis have similar symptoms but are different in the manner in which they affect the digestive tract.

Each condition also has different surgical options and may be treated with a spectrum of diverse medications. The most common symptoms include, but are not limited to:


Several diagnostic tests are normally completed and studied by a digestive specialist before a diagnosis of IBD is made. The "gold standard" for diagnosis is considered the colonoscopy. During this test, a fiber optic tube is inserted into the rectum while the patient is sedated to allow the doctor to inspect the lining of the large intestine and to take biopsies.

Other tests that may be used for diagnosis include:


Intervals of active disease, or "flare-ups," and periods of no disease activity (remission) are typical of IBD. Prescription drugs are frequently used to prevent inflammation (known as maintenance drugs) or to control an existing flare-up.

Surgery is also sometimes used to treat IBD, and the type of surgery used will vary considerably based on the type of IBD and where in the digestive tract any inflammation is located. Conventional medicines used to treat IBD include:

The Basics of Crohn's Disease

Crohn's disease can affect the small and large intestine as well as other organs in the digestive tract. Unlike ulcerative colitis, which only affects the inner layer of the large intestine, Crohn's disease commonly involves all layers of the intestinal wall. 

Several types of surgery can be used to treat the symptoms and complications of Crohn's disease, yet none are a cure. The most common is the resection, during which surgeons remove a diseased piece of the intestine and reconnect the two cut ends. Ostomy surgery, including colostomy and ileostomy, are other surgical procedures that are sometimes used.

The Basics of Ulcerative Colitis

In ulcerative colitis, the inner lining of the large intestine (colon) and rectum are inflamed. This disease does not affect the small intestine. Surgery for ulcerative colitis always involves removal of the entire colon. 

Surgical options include an ileostomy or ileal pouch-anal anastomosis (IPAA), more commonly called a j-pouch. Most people with ulcerative colitis do not require surgery, but are able to manage their condition with medication. 

Differences Between Crohn's Disease and Ulcerative Colitis

Treatment for IBD is currently based on having a diagnosis of either Crohn's disease or ulcerative colitis, so it is important to define the differences between them.

Here are some key differences:

  • In ulcerative colitis, inflammation is in the large intestine, while in Crohn's disease, inflammation could appear anywhere in the digestive tract.
  • The inflammation in Crohn's disease affects all layers of the intestinal walls, while in ulcerative colitis only the inner layer is affected.
  • Smoking cigarettes may worsen Crohn's disease, but some people with ulcerative colitis only develop the disease after they stop smoking.
  • Biopsies from the intestine of a person with Crohn's disease may show granulomas, which are not found in people with ulcerative colitis.
  • In ulcerative colitis, inflammation begins at the rectum and moves up in a continuous manner through the large intestine, while in Crohn's disease, inflammation can begin anywhere and appear in patches separated by healthy tissue.
  • Many extra-intestinal and intestinal complications are similar between the forms of IBD, but abscesses, bowel obstructions, fissuresfistulas are more common in people with Crohn's disease and bowel perforation (especially during the first flare-up), colorectal cancer, and toxic megacolon are more common in people with ulcerative colitis.

A Word From Verywell

Unfortunately, the cause of each of these intestinal disorders is poorly understood and neither of them has a cure. The symptoms are distressing, embarrassing, and even debilitating. Research and awareness are necessary in the fight to overcome IBD.

The good news is that treatments are improving every year. There are new medications being tested and approved that have better remission rates and fewer adverse effects than ever before. Support for people with IBD is also more accessible, both online and offline, as the stigma of the condition is being broken down.

Being diagnosed with IBD is difficult and life-altering. However, most people with it live fulfilling lives, get married, have children, and enjoy successful careers. Managing IBD through a close relationship with a gastroenterologist is going to be the key component to achieving remission and avoiding related complications.


Bhandari BM, Kroser JA, Bloomfeld RS, Lynch SP. "Inflammatory Bowel Disease." American College of Gastroenterology 2013.

Crohn's and Colitis Foundation of America. "About Ulcerative Colitis & Proctitis." 2013.

Crohns and Colitis Foundation of America. "What is Crohn’s Disease?" 2013.

Schraag J. "IBD: Current and Future Trends." EndoNurse 01 Dec 2005.

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