Fistulas may develop that connect two different parts of the intestine. Fistulas also may connect the intestine and bladder or the intestine and the skin surface, especially around the anus. Perforation of the small intestine is a rare complication. In children, gastrointestinal symptoms such as abdominal pain and diarrhea often aren't the main symptoms and may not appear at all. The main symptom may be joint inflammation, fever, anemia, or slow growth.
Some people recover completely after having a single attack affecting the small intestine.
However, Crohn's disease usually flares up at irregular intervals throughout a person's life. Flare-ups can be mild or severe, brief or prolonged. Why the symptoms come and go and what triggers new episodes or determines their severity isn't known. The inflammation tends to recur in the same area of the intestine, but it may spread to other areas after a diseased area has been removed surgically. Diagnosis A doctor may suspect Crohn's disease in anyone with recurring, crampy abdominal pain and diarrhea, particularly if the person also has inflammation in the joints, eyes, and skin.