What is Crohn’s disease?

Crohn’s disease is a chronic inflammatory bowel disease that causes inflammation of the digestive tract. The illness most commonly affects the end of the small intestine (the ileum) and the beginning of the colon.

Although experts still don’t know the exact cause of the condition, a number of factors, such as heredity and a malfunctioning immune system, may play a role in its development. 

According to the Crohn’s Disease & Colitis Foundation, nearly 780,000 Americans may be living with Crohn’s disease. Although the illness can occur at any age, the disease primarily strikes adolescents and young adults between ages 15 and 35.

What are the symptoms of Crohn’s disease?

A chronic condition, Crohn’s disease is characterized by periods during which people experience flare-ups that cause symptoms and periods of remission when there are no symptoms or signs.

Symptoms and signs include:

  • Ongoing bouts of diarrhea
  • Fever
  • Fatigue
  • Abdominal pain and cramping
  • Blood in the stool
  • Mouth sores
  • Reduced appetite and weight loss
  • Pain or drainage near or around the anus

Individuals with severe Crohn’s disease may also suffer from inflammation of the skin, eyes, joints, liver or bile ducts. In children, the illness may delay growth or sexual development.

In addition, Crohn’s disease can lead to complications, such as ulcers, malnutrition, bowel obstruction, colon cancer and anal fissures (small tears in the tissue that lines the anus or the skin around the anus).

What are the risk factors for Crohn’s disease?

According to the Mayo Clinic, risk factors for Crohn’s disease may include the following conditions:

  • Age: Crohn’s can occur at any age, but most people who develop the disease are diagnosed before they’re around 30 years old.
  • Ethnicity: Crohn’s disease can affect any ethnic group, but whites and people of Eastern European (Ashkenazi) Jewish descent have the greatest risk. But incidence of the illness is on the rise among Black people who live in North America and the United Kingdom.
  • Family history: There is a high risk of developing Crohn’s disease if a family member, such as parent, sibling or child, has the disease.
  • Cigarette smoking: This risk factor for developing Crohn’s disease is the one that’s most controllable. Smoking may also increase the severity of the disease and the need for surgery.
  • Nonsteroidal anti-inflammatory medications: Although these drugs don’t cause Crohn’s disease, they can lead to inflammation of the bowel, which worsens the  disease. These meds include ibuprofen (Advil, Motrin IB and other brands), naproxen sodium (Aleve) and diclofenac sodium (Voltaren) among others.
  • Location: Living in an urban area or in an industrialized country increases a person’s likelihood of developing Crohn’s disease.

How is Crohn’s disease diagnosed?

Crohn’s can be diagnosed using a combination of methods, including blood tests and other procedures. Doctors usually conduct blood tests to check for anemia or infection as well as for hidden (occult) blood in a person’s stool. 

A colonoscopy, CT scan or MRI may also be used to diagnose Crohn’s. In some cases, doctors may use a capsule endoscopy—swallowing a capsule that contains a camera—to check the digestive tract. When a capsule endoscopy reveals an abnormality, but doctors are still unable to make a diagnosis, a balloon-assisted enteroscopy may be done. In this procedure, doctors use a scope in conjunction with an overtube to view further into the small bowel, where standard endoscopes don’t reach.

How is Crohn’s disease treated?

Although there’s currently no cure for Crohn’s disease, medical treatment can help reduce the inflammation that triggers symptoms and improve long-term outcomes for the illness. Doctors may also prescribe anti-inflammatory drugs, immune system suppressors and antibiotics, among other medications.

In addition, physicians may recommend diet and lifestyle changes. For example, a special diet administered via a feeding tube or nutrients injected into a vein could help improve overall nutrition and allow an individual’s bowel to rest, which temporarily reduces inflammation.

If all else fails, surgery to remove diseased parts of the digestive tract and reconnect the healthy parts is another option. But this procedure offers only temporary benefits. Crohn’s disease frequently recurs near the reconnected tissue, therefore medication is required to minimize the risk of reoccurrence.

Last Reviewed: March 8, 2019