Prognosis of ulcerative colitis differs between patients with complete and partial mucosal healing, which can be predicted from the platelet count

AIM:To determine the difference in clinical outcome between ulcerative colitis(UC)patients with Mayo endoscopic subscore(MES)0 and those with MES 1.METHODS:UC patients with sustained clinical remission of 6 mo or more at the time of colonoscopy were examined for clinical outcomes and the hazard ratios of clinical relapse according to MES.Parameters,including blood tests,to identify predictive factors for MES 0and slight endoscopic recurrence in clinically stablepatients were assessed.Moreover,a receiver operating characteristic curve was generated,and the area under the curve was calculated to indicate the utility of the parameters for the division between complete and partial mucosal healing.All P values were two-sided and considered significant when less than 0.05.RESULTS:A total of 183 patients with clinical remission were examined.Patients with MES 0(complete mucosal healing:n=80,44%)were much less likely to relapse than those with MES 1(partial mucosal healing:n=89,48%)(P<0.0001,log-rank test),and the hazard ratio of risk of relapse in patients with MES 1 vs MES0 was 8.17(95%CI:4.19-17.96,P<0.0001).The platelet count(PLT)<26×104/μL was an independent predictive factor for complete mucosal healing(OR=4.1,95%CI:2.15-7.99).Among patients with MES 0 at the initial colonoscopy,patients of whom colonoscopy findings shifted to MES 1 showed significant increases in PLT compared to those who maintained MES 0(3.8×104/μL vs-0.6×104/μL,P<0.0001).CONCLUSION:The relapse rate differed greatly between patients with complete and partial mucosal healing.A shift from complete to partial healing in clinically stable UC patients can be predicted by monitoring PLT.