Crohn's disease is a lifelong ailment. The cause of Crohn’s disease is unknown and, at this point, there is no cure, though it can be managed, usually through a combination of medication and surgery. Crohn's can cause problems throughout the gastrointestinal system, but is usually found in the small and large intestines.

Crohn's disease can be broken into two major divisions, according to the Crohn’s & Colitis Foundation of America’s chief medical adviser.? The first division involves the most uniform of Crohn's many symptoms, Dr. R. Balfour Sartor, who is a professor of medicine, microbiology and immunology at the University of North Carolina at Chapel Hill, said. “Everybody (with Crohn's disease) has inflammation,” Dr. Sartor said.

The inflammation caused by Crohn's penetrates deep into the tissue layers of the affected area, and there can be multiple diseased areas broken up by healthy areas of tissue where symptoms aren’t present. The disease can have active phases (with symptoms) and dormant phases (without symptoms).

The other, broader category is that of the complications that the disease causes, Dr. Sartor said. This stage is broken into subsets, including scarring, holes in the intestines (called ulcers), and the potential of intestinal cancer. When the disease causes scarring and narrowing, it can lead to blockages in the intestines. This, in turn, can lead to cramping and vomiting.

Fistulas form when ulcers in the intestines are so severe that they eat their way completely through the tissue of the affected area. They are commonly associated with areas of infection called abscesses. Fistulas can connect to adjacent loops of the intestines, nearby body cavities, or other organs and can cause a host of problems, including malnutrition. If serious enough, the abscesses can be life-threatening.

People who have Crohn's disease have a much higher risk of intestinal cancer, particularly in the colon. The longer someone has had the disease, the more the risk increases, requiring special care in monitoring for cancer.

There is a specific type of Crohn's that affects the colon called Crohn’s colitis or granulomatous colitis. Granulomatous colitis is commonly associated with certain symptoms, according to the foundation. They include fistulas, milder (comparatively) ulcers, and abscesses near the anus. Diarrhea, rectal bleeding, pain in the joints, and skin lesions are also possible.