Key takeaway

  • While Crohn’s disease involves the immune system, experts disagree on whether it is an autoimmune disorder, as the immune response targets healthy gut bacteria rather than the body’s own tissues.
  • The exact cause of Crohn’s disease remains unclear, but research suggests a combination of environmental factors like nonsteroidal anti-inflammatory drugs (NSAID) use and smoking, along with genetic predispositions, may play a role.
  • Although Crohn’s disease can sometimes weaken the immune system, especially when unmanaged or treated with immunosuppressants, well-managed Crohn’s may pose minimal risk of infection.

The exact cause of the disease is still unclear, but researchers have several theories. The most prominent theories claim that genes, an autoimmune response, environmental factors, or a combination of all are responsible.

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

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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.

The immune system links to Crohn’s disease, but it is unclear what causes this involvement.

Some hospitals, such as Johns Hopkins, label Crohn’s disease as an autoimmune disease because it involves 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.

The immune system can malfunction in people with Crohn’s disease. 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 immunocompromisation. 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

Immunomodulators suppress the immune system. Examples of immunomodulators include azathioprine (Azasan), 6-mercaptopurine, 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

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.

Aminosalicylates

Aminosalicylates include mesalamine (Lialda) and sulfasalazine (Azulfidine).

Biologics

Biologics do suppress the immune system.

Examples of biologics include:

People taking medications for Crohn’s disease with concerns 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 frequent use of NSAIDs and smoking.

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

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

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:

The life expectancy of someone with Crohn’s disease is around 78.4 years for those assigned female at birth and 75.5 years for those assigned males at birth.

It is not inevitable that Crohn’s will become worse with age. It may depend on treatment, management of symptoms, and the individual.

Yes, the Social Security Administration labels Crohn’s disease as a disability.

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 contribute to the development of the condition.