Crohn’s disease is a type of inflammatory bowel disease that can affect your entire digestive system. In most cases, it affects the end of your small intestine, known as your ileum.

Crohn’s disease can also affect other parts of your small or large intestines, including your colon. It can cause symptoms that include stomach pains, diarrhea, and bloody stool.

There’s no single diagnostic test for Crohn’s disease. If you show signs or symptoms of the condition, your doctor may use a variety of tests to check for it. For example, they may order blood tests, stool tests, imaging tests, colonoscopy, sigmoidoscopy, or tissue biopsies.

Symptoms of Crohn’s disease vary from person to person and can range from mild to severe. Symptoms include:

The symptoms vary from one person to another, and many other conditions cause similar symptoms. Because of this, it can take a long time to get an accurate diagnosis of Crohn’s disease.

Your doctor will likely start by asking you about your medical history. They may also conduct a full physical examination, order blood tests, and order stool tests. This can help them rule out other possible causes of your symptoms. If they suspect you may have Crohn’s disease, they will likely order other follow-up tests.

To diagnose Crohn’s disease, your doctor will need to see what’s going on inside your digestive tract. To do so, they may use imaging tests that create pictures of your digestive tract from the outside, such as X-rays.

Your healthcare professional may also use an endoscope to look inside your digestive tract during a colonoscopy or sigmoidoscopy. During these procedures they may collect samples of tissue for testing.

If left untreated, Crohn’s disease can lead to potentially serious complications. It can cause intestinal scarring, fistulas, or obstruction of your bowels. It also raises your risk of colon cancer. In severe cases, Crohn’s disease can be life threatening. While there’s no known cure, proper treatment can help you live a normal life.

Blood test

Blood tests can help your doctor check for signs of infection or antibodies in your blood. If you have increased levels of white blood cells or platelets in your blood, it may be a sign of infection or inflammation in your body. The inflammation might be caused by Crohn’s disease or other inflammatory conditions.

Your doctor can’t use a blood test alone to diagnose Crohn’s disease. But it can help them assess the likelihood that you have it.

Stool test

Your doctor may order a stool test to check for blood in your stool. Blood in your stool is a sign of digestive problems, such as Crohn’s disease. They may also order stool tests to check for disease-causing organisms in your digestive tract. This can help them rule out other possible causes of your symptoms.

For example, a stool culture can help them learn if you have a bacterial infection. A stool ova and parasites test can help them learn if you have a parasitic infection.

You will need to provide a sample of your stool, or feces, for a stool test. It will be tested for abnormalities in a laboratory. While you may feel uncomfortable about providing the sample, the process shouldn’t be painful or pose any risk of side effects.

Imaging tests include X-rays, MRI scans, CT scans, and the upper gastrointestinal (UGI) series. They allow your doctor to examine your digestive tract from the outside. This helps them assess and document signs of damage or inflammation. It can help them diagnose Crohn’s disease and its potentially serious complications, such as fistulas or abscesses.

Sometimes your doctor will ask you to drink a solution before undergoing imaging tests. Two different solutions, barium and Gastrografin, are used. Which one you end up taking will depend on the particular test that your doctor orders. It helps your doctor to see your digestive tissues in greater detail.

If your doctor suspects that you have Crohn’s disease, they will likely use one of the following imaging tests to create images of your small intestine:


Using radio waves and magnets, MRI scans allow your doctor to view objects inside your body.

A constant magnetic field and radio frequencies bounce off of the fat and water molecules in your body. Radio waves are transmitted to a receiver in the machine which is translated into an image of the body that can be used to diagnose issues.

You’ll be asked to lie still while the MRI is taking place. An MRI is also a loud machine, and you should be offered earplugs or headphones to make the noise more bearable.


A CT scan, or CAT scan, is a form of X-raying that involves a large X-ray machine.

During a CT scan, you’ll be asked to lie down on a table. The table then moves through the CT scan to take cross-sectional pictures inside your body.


The UGI series includes a variety of imaging tests to create a complete picture of your small intestine.

Your doctor may also use imaging tests to examine your stomach or large intestine.


An endoscope is a thin, flexible tube with a camera on the end. Your doctor can insert it through your rectum to examine the inner walls of your colon. They can use it to conduct different types of endoscopy, including colonoscopy or sigmoidoscopy.

During a colonoscopy, they can view your entire colon. During a sigmoidoscopy, they will only examine the end of your colon. Your doctor may also need to perform an upper endoscopy to look at your esophagus, stomach, and the first part of your small intestine. This procedure is called an esophagogastroduodenoscopy, or EGD.

Endoscopy is one of the few tests that allow your doctor to examine the inside walls of your colon. They can also use it to examine the space between your small intestine and colon, where damage from Crohn’s disease is often found.

For example, they may find granulomas. These are small groupings of cells that can only be seen with endoscopy. They usually point to the presence of Crohn’s disease.

While conducting an endoscopy, your doctor may also collect samples of your digestive tissues for testing, in a procedure known as biopsy.

Endoscopy can help your doctor develop an accurate diagnosis. On the downside, it’s an invasive and sometimes uncomfortable procedure.

Capsule endoscopy

Capsule endoscopy is a revolutionary test used when other tests aren’t conclusive.

To undergo a capsule endoscopy, you will need to swallow a small capsule that has a tiny camera inside. This camera creates images of the inside of your small intestine. It can show signs of Crohn’s disease in your small intestine that cannot be seen with an EGD or a colonoscopy.

The benefit of a capsule endoscopy is that it’s minimally invasive. The capsule is designed to pass through your digestive tract without causing discomfort. The downside is that it doesn’t provide biopsy samples.


To conduct a biopsy, your doctor will collect a small sample of digestive tissue for testing. In many cases, they’ll collect the sample while performing a colonoscopy. Then they’ll send it to a lab for analysis. The laboratory technicians will look for signs of inflammation or other problems with your tissues.

Biopsies can help your doctor confirm or understand the results of other tests, including imaging and endoscopy tests.

When preparing for any diagnostic tests, speak with your doctor to find out how to prepare for each upcoming test. This could include avoiding specific foods, fasting, avoiding certain medications or supplements, avoiding smoking, or avoiding intense physical activity.

Your early tests will like be looking for signs of Crohn’s and to rule out similar conditions. Your doctor may then use lab tests and eventually imaging tests and other procedures to confirm any diagnosis.

Make sure to inform your doctor about any of the following:

  • if you didn’t follow any instructions exactly as given (don’t hide anything since many things can affect test result)
  • if you are taking any medications, vitamins, supplements, or following any special diets
  • if anything has changed with your health or medications since you last spoke with them

Bring all of your questions and concerns with you to your doctor so you can keep informed of every step. Feel free to bring a friend or family member with you for support, if the office or clinic allows.

There are currently no known cures for Crohn’s disease. If you’re diagnosed with the condition, your doctor will recommend strategies to help:

  • reduce inflammation
  • minimize symptoms
  • prevent complications

For example, they may recommend lifestyle changes, including changes to your diet. They may also prescribe medications or other treatments.

Anti-inflammatory drugs, immunosuppressive medications, and antibiotics are common medications used to treat Crohn’s disease. Other treatment options include:

Taking steps to reduce your stress levels and keep your immune system healthy may also help keep your symptoms under control.

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