Doctors have been diagnosing acute severe ulcerative colitis (ASUC) using the Truelove and Witts criteria — a framework developed in 1955 — and a new international consensus panel says it's well past time for an upgrade. Published in Clinical Gastroenterology and Hepatology, the updated criteria were developed by a Delphi panel of European, North American, and Asia-Pacific gastroenterologists to reflect the realities of modern treatment.

The core problem? Patients today are often already on corticosteroids or advanced therapies by the time they're evaluated, which can suppress the classic signs and symptoms that the old criteria rely on — causing some genuinely severe cases to be missed.

Key Takeaways:

• A diagnosis in treated patients requires any 2 of 3 major criteria (CRP ≥2x ULN, ≥6 bowel movements/24h, ≥50% with visible blood) plus ≥2 minor criteria (e.g., low albumin, elevated heart rate, low hemoglobin)
• Patients on high-dose corticosteroids get lower thresholds: CRP ≥1x ULN and ≥33% bloody stools
• Endoscopy should confirm diagnosis; CMV infection and toxic megacolon must be excluded
• ESR and fecal calprotectin were not endorsed as useful diagnostic markers

Why it matters: ASUC can be a life-threatening emergency requiring hospitalization or even colectomy. Outdated diagnostic criteria risk missing patients who need urgent care — especially those already on modern therapies. While the new criteria are a meaningful step forward, experts caution that prospective validation of sensitivity, specificity, and clinical outcomes is still needed before widespread adoption.