Differential Diagnosis Analysis And Scoring Model Establishment Of Crohn's Disease And Enterocutaneous Disease

Background and ObjectiveThe differential diagnosis of Crohn’s disease(CD)and Intestinal Behcet disease(BD)is difficult in clinical practice due to many similarities.The aim of this study was to analyze the differences of clinical manifestations,imaging findings,endoscopic and pathological features of CD and intestinal BD and compare the level of IL17A of intestinal tissues from 6 patients with CD,8 patients with intestinal BD and 5 controls,to further establish a scoring model for distinguishing CD and intestinal BD.MethodsThe first part:(1)The clinical data of 128 patients with CD and 128 patients with intestinal BD who received treatment at the Peking Union Medical College Hospital from January 2004 to March 2017 was retrospectively analyzed,including clinical manifestations,endoscopic features,imaging findings and pathological features.Chi-square test or fisher’s exact test(for the categorical variables)and t-test(for the continuous variables)were conducted by SPSS 22.0.Indicators with P<0.05 were included in the binary logistic regression model and statistical differences were defined as P<0.05.(2)The level of IL17A of intestinal tissues from 6 patients with CD,8 patients with intestinal BD and 5 controls who received operation at the Peking Union Medical College Hospital from January 2004 to March 2017 was retrospectively analysed by immunohistochemical staining.Continuous variables were presented as median and interquartile ranges and non-parametric test(Mann-Whitney U)was used by GraphPad Prism 5.0.Satistical differences were defined as P<0.05.The second part:The clinical manifestations,imaging findings,endoscopic and pathological features of 24 patients with CD and 53 patients with intestinal BD were analyzed using the chi-square test or fisher’s exact test(for the categorical variables)and the t-test(for the continuous variables).For indicators with P<0.2,binary logistic regression was applied to establish the prediction model for the differential diagnosis of these two diseases,and the model was verified using the method of leave-one-out cross-validation.SAS 9.3 was used for analysis.Results1.(1)In this study,multivariate logistic regression analysis of clinical data showed there was a higher prevalence of males in CD patients compared to intestinal BD patients(OR=1.986,95%CI 1.116～3.532,P＝0.02).Based on clinical manifestations,oral ulcer(OR=0.006,95%CI 0.001～0.064,P<0.001),genital ulcer(OR=0.006,95%CI<0.001～0.079,P<0.001)and skin lesions(OR=0.068,95%CI 0.005～0.961,P=0.047)were more common in intestinal BD patients,while intestinal stenosis(OR=20.4,95%CI 3.9～107.5,P<0.001)were more common in CD patients.Based on colonoscopy,ileocecal lesions were more common in intestinal BD patients(OR=20.4,95%CI 3.9～107.5,P<0.001)while pseudo-polyps(OR=23.003,95%CI 4.076～129.835,P<0.0001),irregular ulcers(OR=6.362,95%CI 2.077-19.487,P=0.001)and cobblestone or nodular appearance(OR=15.388,950%CI 1.278-222.354,P=0.032)were more common in CD patients.Based on imaging characteristics,mucosal polyps were more common in CD patients(OR=9.412,95%CI 1.966～45.045,P=0.005).Based on pathological features,univariate analysisi shows that granulomas(20.4%vs 0,P=0.013)and lymphocytes infiltration of lamina propria(25.5%vs 3.7%,P=0.024)were more common in CD while multivariate logistic regression showed no statistical differences(P>0.05).(2)Result of immunohistochemical staining showed that level of IL17A increased significantly in groups of CD and intestinal BD comparing to control group(15 vs 5,11.5 vs 5,P<0.05).There was no satistical differences between CD and intestinal BD though level of IL17A in group of CD was higher than intestinal BD(15 vs 11.5,P=0.3635).2.The scoring system was established with five variables including oral ulcer,oval ulcer,ulcer of ileocecal valve,ulcer of terminal ileum,intestinal stenosis.The scores ranged from-1 to 1:oral ulcer 0(no),-1(yes);oval ulcer 0(no),-1(yes);ulcer of ileocecal valve 0(no),-1(yes);ulcer of terminal ileum 0(no),1(yes),intestinal stenosis 0(no),1(yes).The area under the operating characteristic curve(ROC)of the objects was 0.9638,indicating that the scoring system is good at differentiation.With a score of 0 as the diagnostic cut-off value,the diagnostic sensitivity,specificity,positive predictive value,negative predictive value,accuracy rate,positive likelihood ratio and negative likelihood ratio of intestinal BD were 95.83%,83.02%,71.9%,97.8%,87.0%,5.68,0.05 and the diagnostic sensitivity,specificity,positive predictive value,negative predictive value accuracy rate,positive likelihood ratio and negative likelihood ratio of CD were 83.02%,95.83%,97.8%,71.9%,87.0%,19.9,0.18.The area under the operating characteristic curve(ROC)of validation was 0.9347 by the method of leave-one-out cross-validation.Conclusion:The whole view from clinical manifestations,imaging findings,and endoscopic features should be considered for differential diagnosis of CD and intestinal BD,and the scoring model may be helpful for clinical practice.Results of immunohistochemical staining showed that IL17A took part in the pathogenesis of CD and intestinal BD.We were not sure IL17A could be as a discriminating indicator for CD and intestinal BD.