Crohn's disease is a complex illness that seems to be caused, at least in part, by an over-active immune system that attacks some of the body's own tissues. The symptoms can come and go, and they can vary from patient to patient — which may be one reason why some patients go undiagnosed for years. But make no mistake about it: if you have any of the symptoms below, you should see a gastroenterologist and get tested for Crohn's disease.
