A new international consensus statement proposes updated diagnostic criteria for acute severe ulcerative colitis (ASUC), replacing reliance on the 1955 Truelove and Witts criteria with a framework that better reflects modern treatment, particularly patients already receiving outpatient corticosteroids or advanced therapies. The consensus was developed by a Delphi panel of gastroenterologists from Europe, North America and the Asia-Pacific region and was published in Clinical Gastroenterology and Hepatology.
For patients already receiving outpatient treatment, the proposed definition requires two of three major criteria plus at least two minor criteria. Major criteria include CRP ≥2× the upper limit of normal, ≥6 bowel movements per 24 hours, and visible blood in ≥50% of bowel movements. Minor criteria include low albumin, tachycardia, nocturnal bowel movements, low hemoglobin, fever or leukocytosis. Lower thresholds are proposed for patients receiving high-dose corticosteroids.
The diagnosis should be confirmed with endoscopy, while CMV infection and toxic megacolon should be excluded. ESR and fecal calprotectin were not included in the proposed criteria.