Crohn’s Disease is a disease in which there is chronic inflammation of the intestines. Primarily there are ulcerations of both types of intestines that is the small and large intestines, but the illness can affect any part of the entire digestive tract from the mouth to the anus. Crohn’s disease is very similar in its manifestation to another illness of similar type which affects similar body organs in similar way, which is known as Ulcerative Colitis. Ulcerative colitis and Crohn’s disease have no medical cure. Once the diseases begin, they tend to fluctuate between periods of inactivity (remission) and activity (relapse). Crohn’s disease commonly begins during adolescence and early adulthood, but it also can begin during childhood and later in life. Crohn’s disease tends to be more common in relatives of patients with Crohn’s disease. It also is more common among relatives of patients with ulcerative colitis. The cause of Crohn’s disease is unknown. Crohn’s disease is not contagious. Diet may affect the symptoms in patients with Crohn’s disease. Activation of the immune system in the intestines is most likely to be important in Crohn’s disease. Normally, the immune system defends the body against harmful bacteria, viruses, fungi, and other foreign invaders. Activation of the immune system causes inflammation within the tissues where the activation occurs. Normally, the immune system is activated only when the body is exposed to harmful invaders. In patients with Crohn’s disease the immune system is activated in the absence of any external invader. The continued abnormal activation of the immune system results in chronic inflammation and ulceration. The susceptibility to abnormal activation of the immune system is genetically inherited. Thus, first degree relatives (brothers, sisters, children, and parents) of patients with Crohn’s disease are more likely to develop these diseases. In the early stages, Crohn’s disease causes small, scattered, shallow, crater-like areas (erosions) on the inner surface of the bowel. These erosions are called aphthous ulcers. With time, the erosions become deeper and larger, ultimately becoming true ulcers (which are deeper than erosions) and causing scarring and stiffness of the bowel. As the disease progresses, the bowel becomes increasingly narrowed, and ultimately can become obstructed. Deep ulcers can puncture holes in the wall of the bowel, and bacteria from within the bowel can spread to infect
adjacent organs and the surrounding abdominal cavity. The different subtypes of Crohn’s disease and their symptoms are: