Acute Severe Ulcerative Colitis: What the 2026 GETECCU Position Statement Means for Patients

For most people living with ulcerative colitis (UC), day-to-day disease management happens outside the hospital: medication adjustments, steroid courses, check-ups, and close contact with a gastroenterology team. Most flares, even uncomfortable ones, can be managed at home. But a small proportion of flares escalate into a medical emergency that requires hospitalisation. This is acute severe ulcerative colitis (ASUC), and a June 2026 position statement from the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) provides one of the most detailed recent clinical summaries of how it should be diagnosed and treated (Ordás et al., 2026).

What Is Acute Severe Ulcerative Colitis?

ASUC is not a separate disease from UC: it is a particularly severe episode of active disease that meets specific clinical thresholds. The standard definition, in use since 1955, comes from the Truelove-Witts criteria. A flare qualifies as acute severe when a patient is passing six or more bloody stools per day, combined with at least one systemic sign of illness: a temperature above 37.8 degrees Celsius, a resting heart rate above 90 beats per minute, a haemoglobin level below 105 g/L, or an erythrocyte sedimentation rate (ESR) above 30 mm/h (Ordás et al., 2026).

These criteria matter because they signal that the inflammation has moved beyond local bowel disease into something that affects the whole body. The combination of blood loss, rapid bowel movements, and systemic inflammation creates real risks: dehydration, anaemia, electrolyte imbalances, and, in the most serious cases, life-threatening complications including toxic megacolon and bowel perforation.

The NHS notes that UC can cause severe flares requiring hospital admission and specialist care, and that for some people surgery becomes part of long-term management (NHS: Ulcerative Colitis).

Why Hospital Admission Cannot Be Delayed

When a flare meets the Truelove-Witts threshold, hospital admission is not optional. The stepwise treatment pathway described in the GETECCU statement is only available in a hospital setting, and delays in starting treatment are associated with worse outcomes, including higher rates of complications and emergency surgery.

Before immunosuppressive treatment begins, the clinical team will rule out infection as a trigger or complication. Two infections in particular can either cause or worsen a severe UC flare: Clostridioides difficile (C. diff) and cytomegalovirus (CMV). Testing for both on admission is standard of care, because treating these with immunosuppression alone would be harmful (Ordás et al., 2026).

The Three-Step Treatment Pathway

Step 1: IV corticosteroids

Intravenous corticosteroids, typically IV hydrocortisone or methylprednisolone, are the first-line treatment for ASUC. They have been the backbone of ASUC management for decades and remain effective as initial therapy. The clinical team formally assesses response at three to five days, using validated scoring tools (such as the Oxford Score or serial CRP measurements) to decide whether IV steroids are working or whether escalation is needed (Ordás et al., 2026).

Roughly half of patients admitted with ASUC respond to IV steroids and can be stepped down to oral therapy and discharged with an optimised long-term plan.

Step 2: Rescue therapy

For the patients who do not respond to IV steroids within three to five days, the next step is rescue therapy. The GETECCU statement describes two established rescue options: ciclosporin (a calcineurin inhibitor that suppresses the immune response) and infliximab (an anti-TNF-alpha biologic). Both have comparable short-term efficacy in steroid-refractory ASUC. The choice between them depends on the patient's prior treatment history, current medication, infection risk, and the clinical team's experience. More recently, newer biologics such as vedolizumab have been explored in this setting, though their evidence base remains more limited (Ordás et al., 2026).

Step 3: Colectomy

When rescue therapy does not achieve adequate response, or when a life-threatening complication (such as toxic megacolon, perforation, or uncontrolled haemorrhage) develops at any point during the admission, urgent colectomy becomes necessary. The operation most commonly performed in the acute setting is a subtotal colectomy with an end ileostomy: the colon is removed, a stoma is created, and the rectal stump is preserved to allow possible future reconstruction (an ileoanal pouch) once the patient has recovered.

The GETECCU statement, in line with other international guidance, emphasises that timely escalation decisions at each step are associated with better outcomes than prolonged observation at any one stage (Ordás et al., 2026).

What This Means for People Living With UC

Most UC flares will not become ASUC. But knowing the warning signs can help people make faster decisions when a flare does escalate.

The signals that warrant urgent contact with your IBD team or, if unavailable, an emergency department are:

• Passing six or more bloody stools in a day
• Feeling significantly unwell at the same time: feverish, weak, heart racing, or notably pale
• Any sudden severe abdominal pain, especially with bloating or tenderness

If a flare is meeting these criteria, waiting it out at home is not safe. The stepwise treatment pathway in the GETECCU statement, and in equivalent guidance from ECCO and the BSG, exists precisely because outcomes are better when treatment starts promptly in hospital.

For people who have already had a colectomy and ileostomy following an ASUC episode: an end ileostomy formed in the acute setting is, in most cases, intended to be temporary. Whether and when further surgery to form an ileoanal pouch or reconnect the bowel is appropriate depends on individual recovery, ongoing bowel health, and detailed conversations with a colorectal surgical team.

This article is an AI-assisted curation of published research and clinical guidance. It is not medical advice. If you have ulcerative colitis and experience a severe flare, contact your IBD team or go to your nearest emergency department without delay.