What is Crohn’s Disease?: Symptoms, Causes, and Treatment

• Crohn’s disease is a type of inflammatory bowel disease (IBD). Other types of IBD include ulcerative colitis and indeterminate colitis.
• People with Crohn’s disease experience symptoms such as consistent diarrhea, bloody stool, and abdominal pain.
• Smoking and a family history of Crohn’s disease heighten your risk.
• There isn’t a cure for Crohn’s disease, but there are ways to help control symptoms and prevent further complications.

Crohn’s disease is a chronic autoimmune disease characterized by persistent inflammation throughout the digestive tract. While it most frequently targets the small intestine and the beginning of the colon, it can affect any part of the gastrointestinal system from the mouth to the anus.

Crohn’s disease is one of the primary types of inflammatory bowel disease (IBD), a group of conditions characterized by chronic swelling and inflammation within the gastrointestinal (GI) tract. While Crohn’s is a common diagnosis, it is distinct from ulcerative colitis (UC), another major form of IBD.

Types of Crohn’s Disease

There are five main types of Crohn’s disease, including:

• Ileocolitis: the most common type, which affects the end of the small intestine and the proximal colon
• Ileitis: affects the ileum, or the longest and last part of the small intestine
• Gastroduodenal Crohn’s disease: affects the stomach and the beginning of the small intestine
• Jejunoileitis: affects the upper half of the small intestine
• Crohn’s colitis: affects the large intestine

Common symptoms of Crohn’s disease may include:

• Severe diarrhea
• Bloody stool
• Fatigue
• Fever
• Abdominal pain or cramps
• Reduced appetite or weight loss
• Mouth sores
• Fistula (pain or drainage near or around the anus due to inflammation from a tunnel in the skin)
• Rectal bleeding
• Liver inflammation or bile ducts (primary sclerosing cholangitis)
• In children with Crohn’s disease (pediatric Crohn’s disease), growth delays may occur

Additionally, people with severe Crohn’s disease may experience symptoms in parts of the body outside of the digestive tract, including:

• Rashes
• Arthritis or joint pain
• Kidney stones
• Developing anemia (iron deficiency)
• Eye inflammation
• Skin tags (usually around the anus)
• Abscesses

Symptoms of Crohn’s disease vary from person to person and can range from mild to severe. Some people may experience persistent symptoms, while others may have sporadic symptoms that come and go (called flare-ups or active disease). Some people with Crohn’s disease may have no symptoms at all, a major indicator of remission.

Crohn’s disease is believed to be caused by a combination of immune, bacterial, and environmental factors. The exact cause of Crohn’s disease is unknown, but it is associated with an exaggerated autoimmune response.

In the body, when the immune system is fighting an infection, it can cause inflammation as it works to eliminate the unwanted germs. Once the germs are gone, the body calms and the inflammation goes away. However, an autoimmune response occurs when the body overreacts to a potential antigen, mistakenly attacking itself and continuing to damage healthy tissues even after the germs have been eliminated, causing chronic inflammation and other issues.

Crohn’s disease can run in families, so there is a possibility that genetic factors may also play a role.

Risk Factors for Crohn’s Disease

Crohn’s disease can affect anyone, but certain risk factors increase the likelihood. Some factors that place you at a higher risk for developing Crohn’s disease include:

• Family history of Crohn’s disease
• Age (most commonly diagnosed between late teens and early 30s)
• Smoking (may double your risk)
• Having an appendectomy (the link between this and Crohn’s disease is still being studied, and you should still have this surgery if it’s medically necessary)

If left untreated, Crohn’s disease increases the risk of complications, including:

• Ulcers
• Anal fissures
• Bowel obstruction or blockage
• Malnutrition
• Colon cancer (colorectal cancer)
• Bowel cancer
• Internal/​intestinal bleeding
• Strictures (an abnormal narrowing of a bodily passage, typically due to scar tissue from inflammation)
• Blood clots

To diagnose Crohn’s disease, a healthcare provider will consult your medical history and symptoms, as well as your family history. Based on your symptoms, you may be referred to a gastroenterologist (a doctor who specializes in digestive diseases).

Your provider will perform a physical exam to look for signs of Crohn’s disease, such as swelling or tenderness in the abdominal area. If needed, the provider may perform additional tests to confirm a diagnosis of Crohn’s disease. These tests may include:

• Blood tests: Blood tests can check blood cell levels for signs of inflammation and for elevated levels of a liver-produced protein.
• Stool tests: Stool tests check for bacteria or parasites, and help rule out infections that can cause diarrhea. Fecal matter may also be used to detect intestinal inflammation.
• Computed Tomography (CT) Scan: These scans can produce X‑ray images of your digestive tract to assess the severity of the inflammation.
• Magnetic Resonance Imaging (MRI): An MRI uses magnetic resonance to create images of the inside of the body. In the case of Crohn’s disease, an MRI can help locate any fistulas in the intestines or anus.
• Endoscopy: An endoscopy is a procedure in which a small camera and light on a thin tube are used to capture photos and videos of the upper GI tract (esophagus, stomach, small intestine). This can help give a better visual of the severity of inflammation.
• Colonoscopy: Like an endoscopy, a small camera and light on a thin tube are used to obtain a better view of the lower GI tract (colon and rectum). Biopsies of the colon are often taken to confirm a Crohn’s diagnosis.

Currently, there is no cure for Crohn’s disease. However, there are treatments that can help manage and relieve symptoms and make it easier to live with the condition.

Medications

Medication is the most common way to treat symptoms of Crohn’s disease. Some prescription medications that may be recommended include:

• Steroids: Steroids can help decrease inflammation in the short term, but they’re not used long-term due to the potential for adverse side effects.
• Antidiarrhea medications: Multiple medications can help stop severe diarrhea.
• Antibiotics: Antibiotics can help treat complications of Crohn’s disease, such as severe infections that can lead to fistulas or abscesses.
• Pain medications: Pain medications and therapies can help reduce pain associated with Crohn’s disease.
• Immunomodulators: These drugs alter the way the immune system functions. Immunosuppressors can help calm the immune system so it’s less likely tot attack your body.
• Biologics: Biologics target specific proteins in the body that cause the immune system to overreact.
• Anti-inflammatory drugs: These drugs may help reduce inflammation, but are most commonly used for those with ulcerative colitis, and provide much more limited benefits to those with Crohn’s disease.

Nutrition Changes

Proper nutrition is one way to limit symptoms of Crohn’s disease in the short term and long term. Inflammation can interfere with nutrient absorption, so certain foods that trigger inflammation may be avoided to manage symptoms, making it essential for those with Crohn’s to maintain a nutrient-dense diet to stay healthy.

Surgery

Surgery may be used for complications such as obstructions, fistulas, or abscesses in Crohn’s disease.

In some cases, colostomy surgery may be needed, particularly if the colon or rectum is diseased, injured, or requires rest. This surgery involves creating a colostomy or ileostomy, which brings part of the intestine to the stomach wall. An opening in the stomach wall, called a stoma, diverts waste through an abdominal opening, draining into a bag (an ostomy bag) instead of through the anus. This may allow people with Crohn’s disease to engage in normal activities and improve their quality of life.

There isn’t a way to prevent Crohn’s disease specifically. However, you can take steps to help reduce symptoms and prevent flare-ups, such as:

• Avoid Foods That Trigger Symptoms: While foods do not cause Crohn’s disease, some foods may trigger inflammation and flare-ups. For many people, avoiding dairy or cutting back on high-fiber or carbonated drinks can help reduce inflammation. It’s recommended to keep a food diary to document what you eat and identify which foods may be causing symptoms. However, it’s important to consult your provider before cutting out foods to ensure you’re getting proper nutrition as you make diet changes.
• Stop Smoking: Smoking causes not only an increase in your risk of developing Crohn’s disease, but it can also worsen the condition once you have it. Smoking can cause inflammation, among other complications, and increases the chances of a flare-up. It can also result in the disease becoming more severe.
• Manage Stress: Stress can increase inflammation, so managing it and caring for your mental health can help. Breathing exercises, physical activity, meditation, and more can help relieve stress.
• Stay well-rested: Getting a good night’s sleep regularly helps the body to rest and recuperate, as well as lowers stress. 

You should see a doctor if you experience any of the following symptoms:

• Bloody stool
• Extreme weight loss
• Changes in bowel habits, such as constipation
• Fever
• Inability to pass gas
• Weakness or fatigue
• Uncontrollable or severe diarrhea
• Severe abdominal pain
• Nausea or vomiting
• Signs of a flare-up

In severe cases, Crohn’s disease can lead to life-threatening complications. You should call 911 or seek immediate emergency medical attention if you or a loved one experiences any of the following:

• Fainting/​passing out
• Signs of a bowel obstruction, such as severe bloating, pain, and inability to pass gas or stool
• Significant blood loss, notably from bloody stool
• High fever (over 100 degrees Fahrenheit)
• Chills, confusion, and/​or difficulty breathing (signs of sepsis)