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, When albuminemia was under 26 g/l its specificity and PPV were 89 % and 86 %. When CRP/albuminemia ratio was higher than 2.5, it had a sensitivity of 59 %, a specificity of 89 %, a PPV of 89 %. Sensitivity, specificity, Results Forty-nine patients who had colectomy were included: 41 had acute severe ulcerative colitis, 6 had treatment-refractory disease and 2 had dysplasia or colorectal cancer. There were 28 patients in DU+ group and 21 patients in DU-group. CRP was significantly higher when patients had DU (98.9

, Conclusion CRP and albuminemia are the most accurate tests to identify DU in UC, especially when CRP is over 100 mg/l. If we could confirm those results in a prospective cohort