This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.
Recognizing a severe flare
Ulcerative colitis is a chronic inflammation of the lining of the colon. Most flares can be treated at home, but about one patient in four has a severe flare at some point, which can be life-threatening. In 1955, Sidney Truelove and Leslie Witts of Oxford used a simple set of criteria in their landmark trial of cortisone. Seventy years later, their definition of acute severe colitis is still the standard trigger for hospital admission.
The criteria
Severe flare, all of:
- 6 or more bloody stools a day
- And at least one sign of systemic illness:
- temperature above 37.8°C (100°F)
- heart rate above 90 per minute
- hemoglobin below 10.5 g/dL
- ESR above 30 mm/h (CRP above 30 mg/L is widely used instead)
Mild flare: fewer than 4 stools a day, with or without small amounts of blood, and no systemic signs.
Moderate flare: between the two, for example 4 or 5 stools a day with minimal systemic signs.
Example
A patient has 5 stools a day with intermittent blood, temperature 99°F, heart rate 80, hemoglobin 12.5 g/dL, ESR 20 mm/h and CRP 10 mg/L:
- Systemic signs: 0 of 4
- Classification: moderate flare
If the same patient had 8 bloody stools a day and a heart rate of 104, the flare would be severe.
What happens with a severe flare
- Admission to hospital, with a gastroenterologist and a colorectal surgeon involved from the start
- Intravenous corticosteroids, fluids and blood tests every day
- Stool tests to exclude infection, especially Clostridioides difficile, and often a flexible sigmoidoscopy
- Prevention of blood clots, which are more frequent during flares
- Reassessment around day 3: if there is no response, rescue therapy (infliximab or ciclosporin) or colectomy is considered
Limits
The criteria were designed for adults and use simple bedside measures. They do not replace endoscopy, imaging or clinical judgment. Severe abdominal pain, a distended abdomen or signs of shock need urgent assessment for toxic megacolon or perforation whatever the classification.