Crohn’s disease is an immune-mediated inflammatory disease of the gastrointestinal tract and can involve different areas of the digestive tract in different people. It occurs because of a dysregulation of the immune system, but the exact cause is unknown. There may be a genetic and hereditary component, although most people with Crohn’s disease don’t have a family history of the disease. It most commonly affects patients around the age of 13 to 40.  

Factors that may play a role in Crohn’s disease include:

• Genes and family history; people of Eastern European (Ashkenazi) Jewish descent are at higher risk
• Smoking
• Microbiome (gut bacteria) changes
• Other kinds of bacteria and viruses

Crohn’s disease symptoms

Diagnosing Crohn’s disease can be challenging. Symptoms don’t often associate with location or severity of bowel disease inflammation. Symptoms mimicking Crohn’s disease can be present without the actual disease being active, and active disease can be present with no or minimal symptoms.

The most common areas affected by Crohn’s disease are the last segment of the small intestines (ileum) and the large intestine (colon). Signs and symptoms of Crohn’s disease are often based on disease location and inflammation severity, and they can range from mild to severe. There are periods of no signs or symptoms (remission) as well as very active bowel symptoms (flare). With active disease, some signs or symptoms include:

• Diarrhea
• Weight loss/loss of appetite
• Fever
• Fatigue
• Watery diarrhea, which may be bloody
• Abdomen pain or cramping
• Sores or swelling in the eyes
• Draining of pus, mucus or stools from around the rectum or anus (fistula)
• Joint pain and swelling
• Mouth ulcers
• Swollen gums
• Tender, red bumps (nodules) under the skin, which may turn into skin ulcers

Crohn’s disease diagnosis

Your doctor will perform a physical exam to look for signs of Crohn’s disease. Blood and stool studies will be done to rule out other possible causes. Laboratory tests, imaging studies and endoscopic procedures will help provide a precise diagnosis.

Tests that diagnose and monitor flare-ups of Crohn’s disease and response to treatment include:

• Upper endoscopy
• Enteroscopy
• Double or single balloon endoscopy
• Video capsule endoscopy, “pill camera”
• Colonoscopy or sigmoidoscopy
• Confocal laser endomicroscopy
• CT enterography scan of the abdomen
• MRI enterography of the abdomen
• Endoscopic rectal ultrasound
• Surgical exam 

Crohn’s disease treatment

There is no known cure for Crohn’s disease, but therapies can help control symptoms and improve inflammation to help achieve remission. Treatment strategies may include medications, diet/nutrition and surgery. 

Steroids may be used during the initial phase of a flare-up. However, while steroids may help you feel better quickly, they do not actually heal the bowel and are only a short-term option that should be replaced with appropriate long-term medications such as immune modulators and biologics. The Ohio State Inflammatory Bowel Disease Center has many active clinical trials that can be beneficial for Crohn’s patients.

Surgery for Crohn’s disease

Some people with Crohn’s disease may need surgery to remove a damaged or diseased part of the intestine.