Management of Complex Anorectal and Perianal Crohn's Disease.

Perianal symptoms occur in up to 50% of patients with Crohn's disease in other parts of the gastrointestinal tract, and in 5% of patients it is the first manifestation of the disease. The perianal area is often under stress in patients with Crohn's disease, because of the diarrhea, and the fecal urgency, frequency, and incontinence caused by proximal disease. Symptomatic perianal disease can therefore be due to the effects of the stress on an otherwise normal anus, or the result of Crohn's disease in the low rectum and/or perianal tissues themselves. This key distinction should drive the investigation and management of anal and perianal symptoms in patients with Crohn's disease. In this review, the evaluation and management of the various manifestations of Crohn's disease in the perineum and perianal tissues will be described.