Crohn disease

There isn't any single test that can diagnose Crohn's disease. This condition has many symptoms that are the same as those for other health problems.

To make a diagnosis of Crohn's disease, your doctor is likely to gather information from multiple sources. You'll probably go through a combination of exams, lab tests, and imaging studies with these goals in mind:

Rule out other health problems

Make a clear diagnosis of Crohn's disease

Find out exactly which part of the digestive tract is affected

In general, your primary care doctor will do an initial physical exam, take your health history, and do some lab tests to start to zero in on a diagnosis. If they suspect Crohn’s, they’ll send you to a doctor called a gastroenterologist that specializes in Crohn’s disease and other conditions of the gastrointestinal, or “GI,” tract.

Your gastroenterologist is typically the one who does more in-depth exams to get images and other information about the inside of your body. This may include a colonoscopy that takes video and collects tissue samples (biopsies), along with imaging like barium x-ray or MRI, and other tests your GI doctor thinks helpful.

Physical Exam and History

Your doctor will begin by gathering information about your health and your family health history. They’ll do a physical exam and look for symptoms of Crohn’s that usually include:

Belly pain and cramps

Blood in your poop

Diarrhea

Drainage from a painful sore near your anus

Fatigue

Fever

Lack of appetite

Mouth sores

Urgent bowel movements

Weight loss

Lab Tests

Your doctor may request lab tests in order to look for problems that might be linked to Crohn's disease. These tests check for signs of infection, inflammation, internal bleeding, and low levels of substances such as iron, protein, or minerals.

Blood tests may include:

Antibody tests: These help doctors tell if you have Crohn’s or ulcerative colitis:

Anti-Saccharomyces cerevisiae antibody test (ASCA): People with this protein are more likely to have Crohn’s.

Perinuclear anti-neutrophil cytoplasmic antibody test (pANCA): People with this protein are more likely to have ulcerative colitis.

Complete blood count (CBC): It checks for anemia (low numbers of red blood cells) and infection.

C-reactiveprotein: It looks for this protein, which is a sign of inflammation.

Electrolyte panel: Your body might be low on minerals like potassium if you have Crohn’s-related diarrhea.

Erythrocyte sedimentation rate: This gauges the amount of inflammation in your system by measuring the amount of time it takes for your blood to fall to the bottom of a special tube.

Iron and B12 levels: These can be low if your small intestine isn’t absorbing nutrients like it should.

Liver function: The disease can affect your liver and bile duct.

Imaging Studies and Endoscopy

Crohn's disease may appear anywhere along the gastrointestinal tract, from the mouth to the rectum. X-rays and other images can help identify the severity and location of Crohn's disease. These studies may include the following:

Balloon-assisted enteroscopy: There are about 20 feet of small intestines in your body. They curve around and lie on top of one another. This test makes it easier for doctors to look at them. The version most often used for Crohn’s is a double-balloon (or double-balloon assisted) test. There’s also a version with a single balloon. Both types work like this: The doctor uses a special flexible tube called an endoscope, which has a tiny camera on one end. It has either one or two balloons attached behind it. They’ll inflate them and deflate the balloons to move the tube through your intestine. It’s a lot like pulling a curtain onto a rod.

Barium X-rays and other X-rays: A barium X-ray can show where and how severe Crohn's disease is. It is especially helpful for finding any problems in parts of the small intestine that can't be easily viewed by other techniques.

A chalky fluid containing barium is given by mouth or through the rectum. When barium fluid is given by mouth, it is called an upper GI series. When barium fluid is placed in the rectum, it is called a barium enema. The barium fluid flows through your intestines and looks white on X-ray film. This makes it easier to view problem areas. With a barium X-ray, your doctor may be able to see ulcers, narrowed areas of the intestine, abnormal connections between organs, known as fistulae, or other problems.

If barium X-rays show some sign of disease, your doctor may request other X-rays or imaging studies. These X-rays can help identify exactly how much of your digestive tract is affected by Crohn's disease.

Colonoscopy or sigmoidoscopy: Colonoscopy and sigmoidoscopy allow your doctor to directly view the large intestine, which is the lower part of the digestive tract. These techniques can often provide the most accurate information about the intestines. They may be better at finding small ulcers or inflammation than other techniques. They can be used to judge the severity of any inflammation. Colonoscopy is the most important tool in diagnosing Crohn's disease.

During these procedures, a flexible viewing tube is placed through the anus into the large intestine. An image of the inside of the intestine is often projected onto a video monitor. A sigmoidoscopy involves examining the lowest part of the large intestine. A colonoscopy can provide a view of all of the large intestine and often the end of the small intestine, which is frequently affected by Crohn's. In either case, the doctor can directly view the colon to check for signs of ulcers, inflammation, or bleeding. The doctor can also take small samples of tissue to examine under a microscope, known as a biopsy. This helps determine whether the tissue shows signs of Crohn's disease or other problems.

Computed tomography (CT) scan: CT scanning uses computer-aided X-ray techniques to make more detailed images of the abdomen and pelvis than can be seen in traditional X-rays. CT scans can help find abscesses that might not show up on other X-rays. Abscesses are small pockets of infection.

Leukocyte scintigraphy: White blood cells gather at spots in your body where there’s inflammation. For this test, the doctor will take a little blood from your arm and add a harmless amount of a radioactive substance. They’ll put it back in your body and use a special camera to see if the cells travel to spots in your gastrointestinal tract that could signal Crohn’s. It’s not a commonly used test.

Magnetic resonance imaging (MRI): Use of MRI to make a Crohn’s diagnosis is on the rise. This test gives your doctor a clear picture of the inside of your body, but it doesn’t subject you to radiation. It can help your doctor see your small intestines and spot an anal abscess (pus-filled sore) or fistula (tunnel that forms between an abscess and one of your anal glands). When you get this test, you’ll lie on a table that slides into a machine, so let your doctor know if you have a problem with enclosed spaces.

There is currently no cure for Crohn's disease, and there is no single treatment that works for everyone. One goal of medical treatment is to reduce the inflammation that triggers your signs and symptoms. Another goal is to improve long-term prognosis by limiting complications. In the best cases, this may lead not only to symptom relief but also to long-term remission.

Anti-inflammatory drugs

Anti-inflammatory drugs are often the first step in the treatment of inflammatory bowel disease. They include:

Corticosteroids. Corticosteroids such as prednisone and budesonide (Entocort EC) can help reduce inflammation in your body, but they don't work for everyone with Crohn's disease. Doctors generally use them only if you don't respond to other treatments.

Corticosteroids may be used for short-term (three to four months) symptom improvement and to induce remission. Corticosteroids may also be used in combination with an immune system suppressor.

Oral 5-aminosalicylates. These drugs include sulfasalazine (Azulfidine), which contains sulfa, and mesalamine (Asacol HD, Delzicol, others). Oral 5-aminosalicylates have been widely used in the past but now are generally considered of very limited benefit.

Immune system suppressors

These drugs also reduce inflammation, but they target your immune system, which produces the substances that cause inflammation. For some people, a combination of these drugs works better than one drug alone.

Immune system suppressors include:

Azathioprine (Azasan, Imuran) and mercaptopurine (Purinethol, Purixan). These are the most widely used immunosuppressants for treatment of inflammatory bowel disease. Taking them requires that you follow up closely with your doctor and have your blood checked regularly to look for side effects, such as a lowered resistance to infection and inflammation of the liver. They may also cause nausea and vomiting.

Methotrexate (Trexall). This drug is sometimes used for people with Crohn's disease who don't respond well to other medications. You will need to be followed closely for side effects.

Biologics

This class of therapies targets proteins made by the immune system. Types of biologics used to treat Crohn's disease include:

Natalizumab (Tysabri) and vedolizumab (Entyvio). These drugs work by stopping certain immune cell molecules — integrins — from binding to other cells in your intestinal lining. Because natalizumab is associated with a rare but serious risk of progressive multifocal leukoencephalopathy — a brain disease that usually leads to death or severe disability — you must be enrolled in a special restricted distribution program to use it.

Vedolizumab recently was approved for Crohn's disease. It works like natalizumab but appears not to carry a risk of brain disease.

Infliximab (Remicade), adalimumab (Humira) and certolizumab pegol (Cimzia). Also known as TNF inhibitors, these drugs work by neutralizing an immune system protein known as tumor necrosis factor (TNF).

Ustekinumab (Stelara). This was recently approved to treat Crohn's disease by interfering with the action of an interleukin, which is a protein involved in inflammation.

Antibiotics

Antibiotics can reduce the amount of drainage from fistulas and abscesses and sometimes heal them in people with Crohn's disease. Some researchers also think that antibiotics help reduce harmful intestinal bacteria that may play a role in activating the intestinal immune system, leading to inflammation. Frequently prescribed antibiotics include ciprofloxacin (Cipro) and metronidazole (Flagyl).

Other medications

In addition to controlling inflammation, some medications may help relieve your signs and symptoms, but always talk to your doctor before taking any over-the-counter medications. Depending on the severity of your Crohn's disease, your doctor may recommend one or more of the following:

Anti-diarrheals. A fiber supplement, such as psyllium powder (Metamucil) or methylcellulose (Citrucel), can help relieve mild to moderate diarrhea by adding bulk to your stool. For more severe diarrhea, loperamide (Imodium A-D) may be effective.

Pain relievers. For mild pain, your doctor may recommend acetaminophen (Tylenol, others) — but not other common pain relievers, such as ibuprofen (Advil, Motrin IB, others) or naproxen sodium (Aleve). These drugs are likely to make your symptoms worse and can make your disease worse as well.

Vitamins and supplements. If you're not absorbing enough nutrients, your doctor may recommend vitamins and nutritional supplements.

Nutrition therapy

Your doctor may recommend a special diet given by mouth or a feeding tube (enteral nutrition) or nutrients infused into a vein (parenteral nutrition) to treat your Crohn's disease. This can improve your overall nutrition and allow the bowel to rest. Bowel rest can reduce inflammation in the short term.

Your doctor may use nutrition therapy short term and combine it with medications, such as immune system suppressors. Enteral and parenteral nutrition are typically used to get people healthier prior to surgery or when other medications fail to control symptoms.

Your doctor may also recommend a low residue or low-fiber diet to reduce the risk of intestinal blockage if you have a narrowed bowel (stricture). A low residue diet is designed to reduce the size and number of your stools.

Surgery

If diet and lifestyle changes, drug therapy, or other treatments don't relieve your signs and symptoms, your doctor may recommend surgery. Nearly half of those with Crohn's disease will require at least one surgery. However, surgery does not cure Crohn's disease.

During surgery, your surgeon removes a damaged portion of your digestive tract and then reconnects the healthy sections. Surgery may also be used to close fistulas and drain abscesses.

The benefits of surgery for Crohn's disease are usually temporary. The disease often recurs, frequently near the reconnected tissue. The best approach is to follow surgery with medication to minimize the risk of recurrence.