Management of perianal abscess and fistula-in-ano in children

Perianal abscess (PA) and fistula-in-ano (FIA) are common acquired anorectal disorders in children, but their management is still controversial. This study was performed to evaluate our experience with the treatment of PA and FIA in children of different age groups.

A retrospective study was conducted of children below 16 years of age treated for PA/FIA in a pediatric surgery center between January 2002 and April 2006. The standard treatment for PA was incision and drainage (I&D). Judicious probing for fistulae was only performed in recurrent abscess or if a discharge of pus was identified from the anal verge at surgery. Fistulotomy was routinely performed in low fistulae not associated with inflammatory bowel disease (IBD). IBD associated fistulae were treated with topical tacrolimus in the absence of deep seated infection. Patients were divided into 3 age groups: <2 years, 2-8 years and >8 years. Mode of treatment, microbial organisms, recurrence, associated FIA and association with IBD were recorded. The median follow-up period was 6 months (8 weeks-3 years). Fisher's exact test was used for the analysis of categorical variables.

A total of 78 (39 [<2 years]; 17 [2-8 years]; 22 [>8 years]) patients were treated for PA/FIA during the four year period. In children aged <2 years, 33 (85%) had I&D of PA and the other 6 (15%) had fistulotomy. Recurrence was seen in 9 (23%) children, of which 3 (8%) had FIA. In children aged 2-8 years, 13 (76%) had PA and 4 (24%) had a FIA and there were no recurrences. In children >8 years, 12 (55%) had I&D, 1 (4%) had a fistulotomy and 9 (41%) were treated non-surgically. Six of 7 patients with IBD associated FIA were treated successfully with topical tacrolimus. The recurrence rate after primary surgery was significantly higher for <2 years and >8 years age groups compared to the 2-8 years age group. The incidence of FIA identified either at primary operation or during exploration for recurrence was highest (50%) in >8 years age group and lowest (21%) in the <2 years age group. Lactose fermenting coliforms were the most common organisms isolated from pus. The presence of intestinal organisms in pus was associated with significantly higher recurrence rates in children aged <2 years.

Surgery for PA/FIA in children aged <2 years resulted in low recurrence rates and should be considered as the primary treatment. Topical tacrolimus was found to be an effective treatment for IBD associated FIA.