The purpose of this study is prove the need to selection of a extremely severe ulcerative colitis, to identify predictors of colectomy, which will reduce the optimal time for surgery.

Acute severe ulcerative colitis is a life threatening disease,total mortality rate can reach 17%, and the frequency of surgical treatment approximately 40%. Standard conservative therapy in these patients is often ineffective and the optimal timing of the surgical treatment has not yet been established.

In the Russian clinical guidelines for the treatment of ulcerative colitis, the extremely severe ulcerative colitis is added to the classification of the severity.

The extremely severe ulcerative colitis is a severe, according to the criteria of Truelove, Witts and the endoscopic picture of deep, extensive ulcerative defects of the mucosa, up to the muscular layer with the formation of mucosal islets including albumin reduction.

Conservative treatment of patients with extremely severe ulcerative colitis worsens treatment outcomes only. The authors of the study want to prove that patients with a extremely severe ulcerative colitis need a colectomy in a short time.

Is there a need for long-term follow-up, conservative treatment of high-risk patients? Is it safe to perform early surgical treatment without long-term conservative treatment? This study will allow to answer these questions and help doctors in the treatment of such patients anywhere in Russia and not only.

Inclusion Criteria:

• Acute Severe Colitis according to the Truelove and Witt's Criteria;
• Extremely severe activity according endoscopic picture of deep, extensive ulcerative defects of the mucosa, up to the muscular layer with the formation of mucosal islets including albumin reduction (lower 31 g/l).

Exclusion Criteria:

• Pregnancy;
• Infectious, ischemic colitis;
• Transformation of diagnosis into Crohn's disease;
• Medical treatment failure before the admission.

Patients who admissions with acute severe ulcerative colitis and classified as extremely severe UC.