Table of ContentsView AllTable of ContentsImagingLabs and TestsDifferential DiagnosesFrequently Asked QuestionsNext in Crohn’s Disease GuideHow Crohn’s Disease Is Treated

Table of ContentsView All

View All

Table of Contents

Imaging

Labs and Tests

Differential Diagnoses

Frequently Asked Questions

Next in Crohn’s Disease Guide

DiagnosingCrohn’s diseasecan take time and careful consideration for several reasons. This form of inflammatory bowel disease (IBD) has symptoms similar to other conditions, which can make diagnosis problematic. In addition, distinguishing Crohn’s disease fromulcerative colitis(and vice versa) can also be challenging.

Receiving an accurate diagnosis of Crohn’s disease and starting treatment right away is important to avoid complications from the progression of the disease. There may be several tests that are used to help diagnose Crohn’s disease and to pinpoint the location(s) of any inflammation.

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Crohn’s disease diagnosis

There are several types of imaging tests used to diagnose Crohn’s disease.

Colonoscopy

Acolonoscopyallows a look inside the large intestine (colon). During this test, a physician may see the characteristics of Crohn’s disease inside the large intestine. This can include inflamed areas or ulcers that may occur in patches. Inflammation in the lining of the colon may look red and swollen and ulcers may look like rows or tracts. There can be diseased tissue and healthy tissue alternating in different areas of the colon.

It’s important to follow instructions closely to ensure the test goes as well as possible and that the physician can get a clear, unobstructed view of the colon wall.

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Small pieces of tissue (biopsies) will be taken during a colonoscopy so that the cells from both the inflamed areas and the healthy areas can be examined more closely and tested in a lab. The results of these biopsies can help in making the diagnosis.

After the colonoscopy is over, patients are monitored for a little while and given instructions and any restrictions for the rest of the day. Most people can return to their regular activities the day after the test.

Upper Endoscopy

Anupper GI endoscopy andenteroscopyis a test that is done to look inside the esophagus, stomach, and duodenum. Because Crohn’s disease can affect the upper digestive tract as well as the lower, this test might be used to look for any patches of disease in these organs.

A tool called a fiberoptic endoscope that has a light and a camera is inserted through the mouth and down through the esophagus, stomach, and into the first section of the small intestine. Biopsies will be taken in order to look at the tissue more closely and observe any signs of Crohn’s disease.

Preparation for an upper endoscopy involves fasting for several hours before the test so that the stomach is empty of any food. The test is done with the use of sedation in order to minimize discomfort, but patients are awake during the test in order to be able to respond to instructions. This means, however, that patients will need someone to take them home after the test.

The throat is numbed during the procedure, but the effect should wear off soon after the test is completed. If there are any results to report, the physician might be able to talk about them after the test, but there may also be a need for a follow-up to discuss next steps.

In some cases, the physician completing the test may be able to give some insight as to what was found (if anything) during the test, and there may also be a follow-up scheduled to go over any results more carefully. If there’s a diagnosis of Crohn’s disease, there will also be a need for a treatment plan to be put in place.

Computed Tomography Enterography (CTE) Scan

A magnetic resonance enterography (MRE) is able to produce even more detailed pictures than a CTE, further differentiating between old and new inflammation, plus showing strictures or narrowing or signs of fibrosis.

The CT scanner is a machine that has a round opening in the middle. Patients lie on a table that slides into the opening of the scanner during the test. It will be necessary to stay still during the test, as the machine rotates around and takes the images. At times, a technician will also give instructions to hold the breath for a few seconds at certain times.

Patients are asked to fast about four hours prior to the test, drinking only water. Contrast is given during a CT scan, which helps with the visualization of the organs. The contrast may be given as a drink, in an IV, or as an enema.

For oral contrast, patients are given a drink containing barium to swallow, which is often easier to do if it’s been chilled and while using a straw. During the test, contrast dye will also be given through an IV. Lastly, if necessary, an enema containing barium may be given. All these types of contrast will help in visualizing the digestive organs and in helping physicians make a diagnosis.

Capsule Endoscopy

The preparation for this test includes fasting for several hours beforehand. After the pill is swallowed, patients will wear a monitoring device that will capture the images sent from the camera in the pill as it travels through the small intestine. The camera will take photos all through the small intestine to give physicians a good look at the lining.

Patients will go about their normal activities during the day. The camera will pass through the entire digestive system and will leave the body through the anus during a bowel movement. It’s not necessary to retrieve the camera from the toilet, it can be flushed.

The device that’s worn to capture the images will need to be returned to the physician’s office in order to retrieve the images. A follow-up appointment may be made in order to discuss any findings on the photos and if treatment is needed.

3:01What You Don’t Know About Crohn’s Disease

3:01

What You Don’t Know About Crohn’s Disease

Blood tests won’t be used solely to diagnose Crohn’s disease but may be helpful in understanding how the disease has affected the body.

Two blood tests that may be ordered include the red blood cell and white blood cell counts. These tests will give information on the effects any blood loss and inflammation are causing. Other blood tests, includingC-reactive protein (CRP)anderythrocyte sedimentation rate(ESR), are used to measure inflammation in the body.

Liver function tests, an electrolyte panel, and a vitamin B12 level may also be done because while they’re not diagnostic, they can provide clues to how the IBD is causing effects outside the digestive system.

Stool Tests

Stool tests might be used to look for blood and also to rule out other potential conditions that could be causing symptoms. These tests won’t be used to diagnose Crohn’s disease alone. Stool collection is done either at home or at a lab, where the stool is placed into a sterile container and sent for testing.

Some of the potential findings could include bacteria, blood, or parasites. Bacterial infections are not uncommon in people with IBD, so it might be necessary to rule one out or to confirm it.

A very important stool test in the diagnosis and management of Crohn’s disease is afecal calprotectin test. This test examines stool samples for calprotectin, a protein found in white blood cells that signifies inflammation is likely present in the digestive tract and the body’s white blood cells have been activated as a defense mechanism.

What Are My Treatment Options for Crohn’s Disease?

Frequently Asked QuestionsNo. A blood test alone can’t diagnose Crohn’s disease, but it can provide important information about your overall health and the impact the disease has had on your body so yoursymptomscan be properly treated.The most common symptoms of Crohn’s, includingdiarrhea, weight loss, andabdominal pain, can be mistaken for many other disorders. Further complicating the process is the fact that there is no single definitive test that allows doctors to diagnose Crohn’s disease.

No. A blood test alone can’t diagnose Crohn’s disease, but it can provide important information about your overall health and the impact the disease has had on your body so yoursymptomscan be properly treated.

The most common symptoms of Crohn’s, includingdiarrhea, weight loss, andabdominal pain, can be mistaken for many other disorders. Further complicating the process is the fact that there is no single definitive test that allows doctors to diagnose Crohn’s disease.

3 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institute of Diabetes and Digestive and Kidney Diseases.Diagnosis of Crohn’s diseaseGecse KB, Vermeire S.Differential diagnosis of inflammatory bowel disease: imitations and complications. Lancet Gastroenterol Hepatol. 2018;3(9):644-653.Ha F, Khalil H.Crohn’s disease: a clinical update.Therap Adv Gastroenterol. 2015;8(6):352-359. doi:10.1177/2F1756283X15592585Additional ReadingCrohn’s and Colitis Foundation. Diagnosing Crohn’s Disease and Ulcerative Colitis. 31 May 2010.The National Institute of Diabetes and Digestive and Kidney Diseases. Diagnosis of Crohn’s Disease. National Institutes of Health. Sept 2017.

3 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institute of Diabetes and Digestive and Kidney Diseases.Diagnosis of Crohn’s diseaseGecse KB, Vermeire S.Differential diagnosis of inflammatory bowel disease: imitations and complications. Lancet Gastroenterol Hepatol. 2018;3(9):644-653.Ha F, Khalil H.Crohn’s disease: a clinical update.Therap Adv Gastroenterol. 2015;8(6):352-359. doi:10.1177/2F1756283X15592585Additional ReadingCrohn’s and Colitis Foundation. Diagnosing Crohn’s Disease and Ulcerative Colitis. 31 May 2010.The National Institute of Diabetes and Digestive and Kidney Diseases. Diagnosis of Crohn’s Disease. National Institutes of Health. Sept 2017.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

National Institute of Diabetes and Digestive and Kidney Diseases.Diagnosis of Crohn’s diseaseGecse KB, Vermeire S.Differential diagnosis of inflammatory bowel disease: imitations and complications. Lancet Gastroenterol Hepatol. 2018;3(9):644-653.Ha F, Khalil H.Crohn’s disease: a clinical update.Therap Adv Gastroenterol. 2015;8(6):352-359. doi:10.1177/2F1756283X15592585

National Institute of Diabetes and Digestive and Kidney Diseases.Diagnosis of Crohn’s disease

Gecse KB, Vermeire S.Differential diagnosis of inflammatory bowel disease: imitations and complications. Lancet Gastroenterol Hepatol. 2018;3(9):644-653.

Ha F, Khalil H.Crohn’s disease: a clinical update.Therap Adv Gastroenterol. 2015;8(6):352-359. doi:10.1177/2F1756283X15592585

Crohn’s and Colitis Foundation. Diagnosing Crohn’s Disease and Ulcerative Colitis. 31 May 2010.The National Institute of Diabetes and Digestive and Kidney Diseases. Diagnosis of Crohn’s Disease. National Institutes of Health. Sept 2017.

Crohn’s and Colitis Foundation. Diagnosing Crohn’s Disease and Ulcerative Colitis. 31 May 2010.

The National Institute of Diabetes and Digestive and Kidney Diseases. Diagnosis of Crohn’s Disease. National Institutes of Health. Sept 2017.

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