Perianal abscess and fistula-in-ano in children. The authors present a retrospective review of 40 pediatric patients with perianal abscess and/or fistula-in-ano. The total patient population could be divided clinically into 2 broad groups. The first group consisted of 22 infants younger than 2 years of age, all of whom were males, and 10 of whom presented with recurrences after previous incision and drainage. Of the 14 infants presenting with an abscess, in 12 (85.7 percent), a fistula-in-ano was discovered at surgery. In contrast, in the group of 18 children older than 2 years of age, there were 7 females and 11 males, and fistulas were identified in only 7 of 13 patients (54.8 percent) who presented with abscesses. Surgical treatment consisted of examination under anesthesia and a diligent search for a fistulous tract. Abscesses were primarily saucerized and fistulotomy and cryptotomy of the confluent crypt was performed if a fistulous tract was identified. The only recurrences with this form of treatment occurred in the two immunocompromised patients. 