Management of anal fistulas in Crohn’s disease after failure of Infliximab.

Introduction: Treatment of complex perianal fistulas in Crohn's disease remains a challenge especially after the failure of Infliximab.

Aim: Update on the different therapeutic alternatives for anal fistula in Crohn's disease after failure of Infliximab.

Methods: A research in the medical literature on PubMed and Google Scholar was carried out. We included cohort studies, reviews and randomized double-blinded therapeutic trials. Case reports and fundamental research studies have been excluded.

Results: Anti-TNF therapy, notably Infliximab remain the therapeutic option of choice. Since Infliximab efficacy has been estimated at 60%, with a significant loss-of response rate, new therapeutic strategies have been evaluated and may offer new opportunities for the management of anal fistulas: for example, Ustekinumab could be effective after failure of anti-TNF therapy, although further studies are required. Recent guidelines suggest that injection of mesenchymal stem cells is an effective and safe treatment for complex fistulas. Other surgical options have been proposed, such as endorectal advancement flap, fibrin glue injection, anal fistula plug and ligation of the intersphincteric fistula tract, but all with limited and debatable efficacy. Given the failure rate of all these options, new strategies are currently being evaluated.

Conclusion: Anal fistulas in Crohn's disease are a real therapeutic challenge. New medical and surgical therapies are currently being evaluated, with promising results.