Guidelines for the Multidisciplinary Management of Crohnʼs Perianal Fistulas

Perianal fistulas are common manifestations of Crohn's disease that can result in tremendous morbidity, including scarring, persistent drainage, and fecal incontinence. The typical course for patients with perianal Crohn's disease includes long time periods of actively draining fistulas and frequent relapses.1 The risk of developing Crohn's perianal fistulas increases the more distal the disease involvement. Only 12% of patients with isolated ileal disease develop a perianal fistula compared with 92% of patients with rectal involvement.2 The frequency of perianal fistulas in patients with Crohn's disease range from 17% to 43% in reports from referral centers.3,–12 Three population-based studies have shown similar rates of perianal fistulas between 21% and 23% in patients with Crohn's disease.1,2,13 Approximately, 5% of individuals will have isolated perianal disease without any evidence of luminal inflammation. In Olmsted County, Minnesota population, perianal disease was present at or before time of diagnosis in 45% of cases; 55% were found at median of 4.8 years (8 d–18.7 yr) after diagnosis.1 This underscores the difficulty in making the diagnosis of Crohn's disease in patients who present with only perianal pathology.