Clinical assessment of fistulizing crohn's disease patients

Objective: Perianal fistulizing Crohn's disease is a specific subtype of Crohn's disease characterized by a penetrating behavior. Aside from infliximab, there are no agents with high-level evidence for the treatment of perianal fistula. Most existing treatments do not have studies specifically focused on perianal Crohn's disease. This study aims to evaluate the clinical and laboratory data, and the need for surgery during follow-up in patients with complicated perianal fistulas (excluding simple perianal fistulas). It also aims to investigate the parameters that are effective in achieving clinical and radiological remission of perianal fistula, considering the treatments received. Materials and Methods: The clinical visit notes, laboratory data, imaging results, patient files, and electronic archive system records of perianal Crohn's patients followed between 1999 and 2022 at Istanbul University Cerrahpaşa, Cerrahpaşa Medical Faculty Gastroenterology Clinic were retrospectively reviewed. Results: As the number of perianal fistulas increases, healing rates decrease. A newly defined subgroup of intersphincteric fistulas showed more healing compared to other types, and the absence of terminal ileum involvement in current luminal disease was associated with fistula healing. Conclusion: While triple combination therapy (AZA+IFX+antibiotic) applied for at least 3 months was not effective in radiologically closing perianal fistulas, the absence of terminal ileum involvement, fewer fistulas, and type A intersphincteric fistulas facilitated healing. Dose maximization and combination therapy, including stoma as needed, enhance clinical and radiological remission. Keywords: anal fistula, complex perianal fistula, penetrating Crohn's disease