Crohn’s disease is a form of inflammatory bowel disease (IBD) with a suspected link to an inflammatory immune response. The exact cause of the disease is still unclear, but researchers have several theories. According to the most prominent theories, either the genes, an autoimmune response, or environmental factors are responsible.

The autoimmune response theory is based on the fact that the immune system attacks otherwise harmless bacteria that are present throughout the body’s gastrointestinal (GI) tract. This immune response causes chronic inflammation, which can lead to the variety of symptoms and complications associated with Crohn’s disease.

This article looks at whether Crohn’s disease is an autoimmune condition and whether people with the condition are immunocompromised. It then describes the potential causes of Crohn’s disease and lists some related conditions.

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Although some experts believe that Crohn’s disease may be an autoimmune response or disorder, others have expressed some doubt.

An autoimmune disorder occurs when the body’s immune system mistakenly attacks an otherwise healthy part of the body. However, Crohn’s disease is different than autoimmune diseases. Rather than attacking a part of the body, it seems that the immune system actually attacks the healthy bacteria present throughout the GI tract.

Both the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and the Crohn’s & Colitis Foundation note that the immune system attacks healthy bacteria, not the body itself. They also say that although the exact cause is unknown, it may involve genetic and environmental factors.

Research has shown immune system involvement in Crohn’s disease, but as a 2020 case study pointed out, it is unclear what causes the immune involvement.

Some hospitals, such as Johns Hopkins, label Crohn’s disease as an autoimmune disease because of the involvement of the immune system.

However, other providers, such as the University of Chicago Medicine, mention immune system overreaction when describing Crohn’s disease but do not refer to it as an autoimmune disease.

In people with Crohn’s disease, the immune system can malfunction. If a person is not able to manage their condition effectively, this may mean that there is too much immune activity in the gut and not enough in the rest of the body.

However, if a person’s condition is well-managed, doctors may not consider them to be immunocompromised. Such individuals may have a minimal risk of infection.

It is important to note, though, that some people may take medications for Crohn’s disease that suppress their immune system.


Immunomodulators suppress the immune system. Examples of immunomodulators include azathioprine (Azasan), 6-mercaptopurine, methotrexate (Trexall), cyclosporine (Restasis), and tacrolimus (Prograf).

The NIDDK notes that immunomodulators have several potential side effects, including increasing the risk of infection. As a result, a doctor will likely only prescribe the medication for more severe cases.


Steroids can suppress the immune system. Examples of steroids include prednisone (Rayos) and budesonide (Ortikos).

As a result, people taking steroids have a higher risk of infection.


Doctors do not believe that aminosalicylates suppress a person’s immune system. Aminosalicylates include mesalamine (Lialda) and sulfasalazine (Azulfidine).


Biologics do suppress the immune system.

Examples of biologics include:

People taking medications for Crohn’s disease who are concerned about their immune system should talk with their doctor.

Researchers are still not sure of the exact cause of Crohn’s disease. However, the disease may develop due to environmental or genetic factors.

Environmental factors

The NIDDK notes that a few different environmental factors may increase a person’s risk of developing Crohn’s disease. Some factors include:

In addition, some environmental factors can cause the condition to get worse. For instance, eating certain foods and experiencing stress can worsen the condition. However, they will not cause it to develop initially.

Learn more about the causes of Crohn’s disease here.

Genetic factors

The Crohn’s & Colitis Foundation notes that 5–20% of those living with IBD also have a family member with the condition.

In addition, it points out that the following genetic factors may cause a person to develop IBD, including Crohn’s disease:

  • both parents having IBD
  • being of African American descent
  • being of Eastern European descent

Learn more about Crohn’s disease and genetics here.

Crohn’s disease is one of many forms of IBD. IBD describes a variety of related conditions that affect the GI tract.

The two most well-known types of IBD are Crohn’s disease and ulcerative colitis. As with Crohn’s disease, ulcerative colitis typically develops over time. However, the disease tends to appear in the large intestine, whereas Crohn’s can affect any part of the GI tract from the mouth to the anus.

Conditions with similar symptoms

Some conditions that can cause symptoms similar to those of Crohn’s disease include:

Crohn’s disease is a type of IBD that is similar to other conditions that affect the GI tract. Although it involves inflammation in the immune system, not all experts consider it an autoimmune disorder because it attacks good bacteria in the GI tract rather than body tissues.

The exact cause is still unknown, but researchers believe that environmental and genetic factors may play a role in the development of the condition.