Six patients each with an extensive ulcerating colitis are reported. Common features were a febrile nonbloody diarrhea; radiological involvement of the whole colon with superficial ulcerations and preservation of haustra, and integrity of the terminal ileum and rectum; the absence of any specific pathological finding; and, most important, the spontaneous recovery of the lesions in the absence of any treatment except sympatomatic measures. The present follow up after recovery range from 18 months to 5 years. Four cases were young women taking oral contraceptives and two patients were older. These patients with colitis could represent a new entity or could be a particular form of Crohn's disease of the colon, with delayed diagnostic pathological features.