Crohn’s Disease

Crohn’s disease is a chronic condition characterized by inflammation of the gastrointestinal tract, particularly in the small intestine and colon.

About Crohn’s Disease

Crohn’s disease is a form of inflammatory bowel disease (IBD), meaning your body’s immune system attacks the gastrointestinal tract. Unlike ulcerative colitis, another variety of IBD that affects the innermost layer of the large intestine only, Crohn’s disease can affect the entire bowel wall as well as the rest of the gastrointestinal system. It is possible for the inflammation to “skip” regions of the gastrointestinal tract, meaning that symptoms can be patchy.

Experts don’t know what causes Crohn’s disease, but condition onset is thought to be influenced by a combination of genetics, immune activity, and the environment.

Crohn’s disease can lead to a serious complication called a fistula, in which inflammation in the intestine causes ulcers so severe that an opening develops between the intestine and some other organ such as the bladder, skin, or vagina. Other complications arising from Crohn’s disease can include intestinal narrowing (called a stricture) and abscesses (pockets of infection).

Types of Crohn’s Disease

Crohn’s disease is categorized in two ways, based on disease location and disease behavior.

Disease location refers to which portions of the gastrointestinal tract are affected by inflammation.

  • Ileocolitis: The end of the small intestine and the large intestine are inflamed
  • Ileitis: Inflammation is confined to the small intestine
  • Gastroduodenal Crohn’s disease: The stomach and the uppermost part of the small intestine are inflamed
  • Jejunoileitis: Only the top half of the small intestine is affected
  • Crohn’s (Granulomatous) colitis: The large intestine is inflamed

Disease behavior refers to what complications have resulted from this inflammation

  • Inflammatory: inflammation in the bowel but no strictures, fistulas or abscesses have occurred
  • Stricturing: inflammation in the bowel that has caused the development of a stricture
  • Penetrating: inflammation of the bowel that had led to the development of a fistula between the bowel and another organ or the development of an abscess

Symptoms of Crohn’s Disease

Symptoms of Crohn’s disease may vary based on where the inflammation is located. The severity of your symptoms may differ over time, and periods of intense symptoms are known as a flare.

Symptoms of Crohn’s disease may include:

  • Constipation or diarrhea
  • Bleeding from rectum
  • Abdominal pain or cramping
  • Loss of energy
  • Loss of appetite
  • Weight loss

Risk Factors for Crohn’s Disease

Certain factors may increase your risk of developing Crohn’s disease. Stress and diet do not cause Crohn’s disease, but they may aggravate your symptoms.

Risk factors for Crohn’s disease may include:

  • Family history: Having a family member with inflammatory bowel disease increases your risk of developing Crohn’s disease
  • Ethnicity: Inflammatory bowel disease can affect persons of any ethnic group. Historically, these conditions were thought to more commonly affect people of white and/or Jewish descent. More recently, the disease has been observed more often across all ethnicities
  • Age: Crohn’s disease can occur at any age, but the condition most commonly develops between the ages of 15 and 35

Diagnosing Crohn's Disease

No single test is definitive for making a diagnosis of Crohn’s disease. Several tests, including those listed below, can help provide the information your physician needs to make a diagnosis.

  • Colonoscopy: This test looks at the entire colon and into the end of the small bowel (called the ileum). A flexible tube with a light and camera is inserted into the rectum and advanced into the colon and allows the physician to see the lining of the bowel. Signs of colitis include redness, swelling, ulcers and bleeding. Samples of the bowel (called biopsies) can also be obtained during this test for further analysis.
  • Biopsy: Often obtained during colonoscopy, these samples allow for the tissue of the colon to be examined under a microscope to look for changes that suggest ulcerative colitis.
  • Stool tests: Stool tests can include multiple pieces of information. They can be used to assess for inflammation in the stool (for example, a calprotectin test), to assess for infections (for example, C. difficile infection), or to evaluate for other causes of diarrhea.
  • Blood tests: No blood tests can diagnose or definitively rule out Crohn's Disease. But some blood tests can be helpful to monitor the disease, monitor medications used to treat the disease, and evaluate for complications related to the disease.
  • Imaging tests: CT or MRI tests can add valuable information about the extent of involvement of Crohn’s in the bowel as well as help identify any complications like abscesses or fistulas. Moreover, these tests compliment the information provided via colonoscopy as they are able to visualize the small bowel out of the reach of the colonoscope.

Treating Crohn’s Disease

Your ideal treatment will vary depending on your symptoms, disease severity, and age. and other health problems. Many patients can manage their condition through medication and diet alone. In severe cases, surgery to remove affected portion of the bowel may be necessary. Surgical intervention may also be required to address complications such as strictures or fistula. Your physician will work with you to determine the most appropriate course of treatment.

Care Team Approach

Patients are cared for by a dedicated multidisciplinary care team, meaning you will benefit from the expertise of multiple specialists across a variety of disciplines. Our board-certified and fellowship-trained gastroenterologists have extensive experience treating inflammatory bowel disease and work alongside a team of digestive health experts, including colorectal surgeons, gastrointestinal-specialized dietitians, clinical social workers, physician assistants, nurses, advanced practice providers, and more, providing unparalleled care for patients every step of the way.

We collaborate with our colleagues at the Dell Medical School and The University of Texas at Austin to utilize the latest research, diagnostic, and treatment techniques, allowing us to identify new therapies to improve treatment outcomes. We are committed to communicating and coordinating your care with referring physicians and other partners in the community to ensure that we are providing you with comprehensive, whole-person care.

Learn More About Your Care Team

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Digestive Health

Health Transformation Building
9th Floor
1601 Trinity Street, Bldg. A
Austin, TX 78712
1-844-GI-AUSTIN (1-844-442-8784)
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Health Transformation Building
9th Floor
1601 Trinity Street, Bldg. A
Austin, TX 78712
1-844-GI-AUSTIN (1-844-442-8784)
Get Directions

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Inflammatory Bowel Disease

Health Transformation Building
9th Floor
1601 Trinity Street, Bldg. A
Austin, TX 78712
1-844-GI-AUSTIN (1-844-442-8784)
Get Directions