What is Crohn’s Disease?

Crohn’s Disease (CD) is classified as an autoimmune disease. An autoimmune disease results in over activity of the immune system, meaning, the body mistakenly attacks and damages its own tissues. This weakens one’s immune system and decreases the body’s ability to fight pathogens, resulting in increased vulnerability to various infections, while also causing inflammation 1.

Typically, the immune system works as a defense system and guards the body against germs like bacteria and viruses. When the immune system senses foreign bacteria in the body, it sends out cells to attack them. Normally, the immune system can detect the difference between foreign cells and the body’s own cells. In those with an autoimmune disease, the immune system mistakes part of one’s body as foreign, and releases proteins called antibodies, and instead fighting infections, these antibodies attack the body’s own tissues 2. Autoimmune diseases are very difficult to diagnose, and medical professionals are still unsure of the exact cause of the diseases.

CD is classified as a type of autoimmune disease in which there is chronic inflammation along any part of the digestive tract – often CD is associated with fistula and ulcers. Although CD causes inflammation that can occur in any area of the gastrointestinal (GI) tract, inflammation is most often present in the lower part of the small bowel and the upper end of the colon 3. CD inflames the lining of the GI tract and hinders one’s body’s ability to digest food, inhibiting proper absorption of various vitamins, minerals, and phytochemicals. The inflammation associated with CD has the potential to damage all layers of the GI tract beginning from the mucosa through submucosa to the muscle through to the peritoneum 3.

CD is more common among females in comparison to males, and on average is misdiagnosed in patients for 7.7 years prior to being officially diagnosed 4. CD is typically diagnosed among individuals between the ages of 15 to 35 years old. Common signs and symptoms of CD include: abdominal pain and discomfort, cramping, bloating, fatigue, loss of appetite, fever, muscle aches, rashes, joint pain, and digestive issues. Many patients with CD are at risk of micronutrient deficiencies, for numerous reasons such as malabsorption, chronic inflammation, intestinal restrictions, and lack of appetite.

As many as 80% of patients with CD will require surgery at some point in their lifetime to treat complications associated with the disease, particularly relating to fistulae, obstructions and abscesses 4. In addition, approximately 40% of patients with CD are hospitalized each year due to some sort of difficulty associated with the disease 4. Although it is difficult to prevent autoimmune diseases, diet plays a large role in reducing negative symptoms associated with the given disease. Depending on the severity of the disease, a diet modification is often suggested among patients with CD prior to beginning medical treatment.

Of those with CD, individuals possess excess amounts of Tumor Necrosis Factor (TNF) 5. Excess TNF is the main source of inflammation, as a surplus of TNF causes ones immune system to mistakenly attack healthy cells in the GI tract, in turn, causing inflammation. Although there is no cure for CD, optimal nutrition and diet as well as medical treatment can help to ease symptoms. The goal of medical treatment for those with CD is for patients to achieve and maintain a state of remission, treat and prevent complications associated with the disease, improve and maintain nutritional status, and enhance quality of life. Remission results when the disease is no longer active, meaning that inflammation has subsided resulting in minimal side effects and symptoms. Often a state of remission is reached in patients who have positively responded to medication treatment and intervention or have undergone surgical resection.

Immunosuppressant’s, such as remicade, azathioprine, cyclosporine, 6-mercaptopurine, tacrolimus, and methotrexate are often prescribed to patients with CD 6. These immunosuppressant’s belong to a class of biologic medications known as TNF-blockers. These medications work to bind to TNF- alpha, blocking its action, and inhibiting inflammation, in hopes to minimize both symptoms and side effects of CD.

Medical professionals are continually doing research in the area of CD to determine the exact cause of origin of the disease, and continuous advancements in medication and treatments are being sought in hopes to minimize flare-ups, complications, symptoms, and negative side effects associated with CD.




[1] Quintero-Ronderos, P. and Montoya-Ortiz, G. (2012). Epigenetics and Autoimmune Diseases. Autoimmune Diseases, 2012, pp.1-16.

[2] Washington, J. (2001). Autoimmune Diseases. JAMA, 285(22), p.2912.

[3] Crohn’s Disease – Crohn’s and Colitis Canada. (2019). Retrieved from https://www.crohnsandcolitis.ca/About-Crohn-s-Colitis/What-are-Crohns-and-Colitis/Crohns-Disease.

[4] Asano, M. (1996). Autoimmune disease as a consequence of developmental abnormality of a T cell subpopulation. Journal of Experimental Medicine, 184(2), pp.387-396

[5] Healthline. (2019). Tumor Necrosis Factor (TNF) for Crohn’s Disease. [online] Available at: https://www.healthline.com/health/crohns-disease/tumor-necrosis-factor#1 [Accessed 10 Jan. 2019]

[6] Ruggiero, V., Antonelli, G., Gentile, M., Conciatori, G. and Dianzani, F. (2006). Comparative study on the antiviral activity of tumor necrosis factor (TNF)-alpha, lymphotoxin/TNF-beta, and IL-1 in WISH cells. Immunology Letters, 21(2), pp.165-169.