We carried out a clinical and endoscopic follow-up study of 14 patients with Crohn's disease of the esophagus. The diagnosis was based on the combination of endoscopic and histologic examinations with exclusion of all other possible causes. All patients had other gastrointestinal localizations of Crohn's disease, including oral and anal disease, and the majority also had serious extra-intestinal manifestations. Complete healing of the lesions was accomplished with corticosteroids in 9/14 patients after 2 to 4 weeks. During a total follow-up of 83 years for the 14 patients, 26 "flare-ups" of intestinal and systemic symptoms having a Crohn's disease activity index greater than 200 were diagnosed, on which occasions UGI endoscopy was performed before adjusting therapy. Three patterns of evolution could be distinguished: (1) in eight patients (total 17 flare-ups), neither endoscopic esophageal lesions nor UGI symptoms were apparent during follow-up. (2) Three patients (1 flare-up each) had persistent lesions despite corticosteroid therapy. (3) Three patients (6 flare-ups, 2 each) had relapse of both symptoms and esophageal lesions on each endoscopy, although these lesions had completely disappeared initially.