 Toxicity is present, as demonstrated by fever, tachycardia, anemia or an elevated ESR or CRP.Fulminant disease correlates with more than 10 bowel movements daily, continuous bleeding, toxicity, abdominal tenderness and distension, blood transfusion requirement, and colonic dilation (expansion).People with fulminant UC may have inflammation extending beyond just the mucosal layer, causing impaired colonic motility and leading to toxic megacolon.