The efficacy of infliximab combined with surgical treatment of fistulizing perianal Crohn's disease: Comparative analysis according to fistula subtypes.

BACKGROUND/OBJECTIVE: Infliximab is regarded as an effective therapeutic to treat Crohn's disease. This study aimed to assess the efficacy of infliximab combined with surgery and to analyze clinical manifestations according to fistula subtypes in patients with fistulizing perianal Crohn's disease.

METHODS: From April 2013 to December 2015, 47 patients with perianal Crohn's disease in two hospitals of South Korea (Goo Hospital, Gangnam Severance Hospital) were evaluated retrospectively. Patients were categorized into two groups as simple fistula (n = 20) and complex fistula group (n = 27). All patients received 5 mg/kg of infliximab intravenously at 0, 2, and 6 weeks after surgical treatments. Then every eight weeks, the responders continued to receive 5 mg/kg infliximab for maintenance therapy.

RESULTS: Complete response of induction therapy was 72.3%, and partial response was 27.7%. After maintenance therapy, complete response was 97.9% and partial response was 2.1%. There was no patient without a response to infliximab in this study. The median time to the first fistula closure was 6.00 ± 8.00 weeks. Infliximab was used on average 2.13 ± 0.71 times until the first fistula closure. The rate of recurrence was 8.5% and adverse events were 4.2%. In comparison with clinical manifestations between simple and complex fistula groups, there was no significant difference except for the coexistence of perianal abscess.

CONCLUSIONS: Combined surgical and infliximab therapy was efficacious to treat fistulizing perianal Crohn's disease with rapid treatment response and favorable clinical outcomes. It is expected that this top-down strategy with combining surgeries can overcome previous limitations in treating perianal Crohn's disease.