Perirectal abscess in Crohn's disease. Drainage and outcome. The role of surgical intervention in the treatment of patients with anorectal Crohn's disease is controversial. To clarify the success of aggressive drainage and the subsequent clinical course of patients with Crohn's disease and perirectal abscesses, the authors reviewed the records of 38 patients who presented with this condition during an eight-year period. Twenty-two male and 16 female patients (median age, 32 years; range, 17 to 61 years) with clinically or pathologically confirmed Crohn's disease of the bowel underwent operation for perirectal abscesses. Thirty-two percent of patients had no previous history of anorectal Crohn's disease. Thirty simple abscesses and 8 complex horseshoe abscesses were treated. At operation, 53 percent of patients underwent incision and drainage whereas 26 percent received loop indwelling drains and 21 percent had mushroom catheters placed. After resolution of the index abscess, recurrent abscesses occurred in 45 percent of the patients who underwent catheter drainage and 56 percent of the patients who underwent incision and drainage. More importantly, 44 percent of the incision and drainage group and only 31 percent of the catheter drainage group required subsequent proctectomy to control perineal sepsis. The healing time of the perineal wound was longer than six months in 83 percent of patients requiring rectal excision. We concluded that long-term catheter drainage may offer substantial benefit in the overall outcome of the treatment of patients with Crohn's disease and perirectal abscess. 