Scientists do not know what causes Crohn's disease, and it cannot be cured. However, some forms of ileitis are caused by bacteria and can be cured by antibiotics. The symptoms of Crohn's disease include periodic attacks of abdominal cramps, fever, and diarrhea. In most cases, these symptoms first appear in people from 15 to 30 years old. The victims feel well between attacks.
Some patients suffer only one or a few attacks, but others have many.
Most victims have mild attacks. During an attack of Crohn's disease, the inner wall of the ileum swells. The swollen wall may block the ileum and prevent food from passing through. Each attack scars the inside wall and adds a layer of scar tissue to it. This thickening of the wall also may clog the ileum.