Fistula-in-ano in infancy and childhood.

The authors report the results of a retrospective study of 36 patients with fistula-in-ano (FIA) and/or perianal abscess (PA) presenting during a 3-year period. In 76.2% of the 21 patients with FIA, the fistulae developed in the first 2 years of life. For eight of the 16 patients who underwent fistulectomy, histological examination of the excised fistulae showed an epithelial lining of the tract mixed with stratified squamous, transitional and columnar epithelium. The early onset of FIA, the high percentage of bilateral and multiple fistulae, and the presence of these types of epithelium lining support a congenital etiology of FIA in children. In boys, a causal relationship exists between PA and FIA.