Crohn's disease of the appendix.

Crohn's disease limited to the appendix is uncommon. The disease may mimic acute appendicitis with fever, leukocytosis, right lower quadrant pain, and occasionally a palpable mass. When Crohn's disease affects the appendix, it typically has a longer clinical period in which the patient has symptoms than do most cases of acute appendicitis. The most common preoperative diagnoses are acute appendicitis and appendiceal abscess. A review of the literature is presented along with our experience in three additional cases of Crohn's disease limited to the appendix. We suggest that Crohn's disease be included in the preoperative differential diagnosis and that extensive intraoperative examination of the gastrointestinal tract be made in any case of suspected appendicitis that has had a protracted preoperative course.