The Clinical Observation On The Treatment Of Crohn’s Disease Anal Fistula With Lateral Mucosal Advancement Flap

Objective:To evaluate the clinical efficacy and safety of lateral mucosal advancement flap as definitive surgical repair in the treatment of perianal fistulizing Crohn’s disease,and to analyze the related factors affecting recurrence.Methods:The clinical data of 23 patients with perianal fistulizing Crohn’s disease who were admitted for the first time in the Department of anorectal surgery,affiliated Hospital of NJUCM from June 2014 to June 2020 were collected and analyzed retrospectively.Patients were followed up regularly by call or out-patient service until March 2021.The short-term and long-term local effect and systemic effect were evaluated by observing fistula healing and comparing pre-and post-operative PDAI and CDAI.The safety of lateral mucosal advancement flap surgery was judged by the comparison of the scores of anal incontinence(Wexner scores)before and after operation.Using T-test and Kaplan-Meier method for single-factor analysis and COX regression for multi-factor analysis to analyze the relevant influencing factors of recurrence.Results:1.Followed up for 6 months,the clinical response rate was 100%.Followed up for 12 months,the fistula closure rate was 95.5%.The total fistula closure rate was 82.6%during a follow-up of 9 to 81 months(a median follow-up of 47 months).The postoperative PDAI score(0.52±1.20)was significantly lower than the preoperative PDAI score(4.3±1.84),and the difference was statistically significant(t=9.77,P<0.001).The postoperative simplified CDAI score(0.87±0.85)was significantly lower than the preoperative simplified CDAI score(1.17±1.09),and the difference was statistically significant(t=2.4,P=0.025).There was no significant difference in Wexner scores before and after operation.2.The accumulation survival rates in this study at 6,14 and 31 months were respectively 95.7%,86.5%and 81.1%.T-test univariate analysis and KM univariate survival analysis showed that the number of external fistula openings is the influencing factor of fistula recurrence(P<0.05).The results of COX regression multivariate survival analysis showed that the number of external fistula openings is the risk factor of fistula recurrence(OR=4.822,95%CI 1.305-17.813;P=0.018).Conclusion:Lateral mucosal advancement flap has a good short-term and long-term effect in the treatment of perianal fistulizing Crohn’s disease without damaging the anal function,so it can be used as one of the recommended definitive operations of perianal fistulizing Crohn’s disease.