Perianal abscess and fistula-in-ano in infants: a different entity?

Purpose: The features of perianal abscess and fistula-in-ano in infants are different from those of older children, and there is controversy regarding their treatment. The aim of this study was to assess the efficacy of various methods used for their management.

Methods: A retrospective analysis of the records was conducted for all infants younger than 24 months of age treated for perianal abscess, fistula-in-ano, or both from 1990 to 2002.

Results: The study included 98 infants. Perianal abscess was found in 77 patients (75 males), and fistula-in-ano in 21. No infant had an underlying illness. Drainage was performed by needle aspiration in 47 patients and by incision and drainage in 5. Following drainage, 43 patients received antibiotics. Altogether, 6 infants were treated with antibiotics alone and 19 with local care alone. Twenty-eight boys (36.4 percent) had an evolution toward fistula-in-ano. Patients who received antibiotics following drainage were less likely to develop fistula-in-ano than were patients who underwent a drainage procedure alone (27.9 percent vs. 66.7 percent, P < 0.05). All patients with fistula-in-ano were male and had been previously treated for perianal abscess (21 patients elsewhere and 28 in our department). Spontaneous cure of fistula-in-ano occurred in 42.9 percent of them (average 3.2 months), and 57.1 percent underwent fistulectomy for persistent fistula-in-ano. Cryptotomy was added when an involved crypt was found (11 patients, 39.3 percent). No recurrence of fistula-in-ano was noted after fistulectomy.

Conclusions: Local treatment for perianal abscess during the early stage and drainage by needle aspiration during the progressive stage are effective. Antibiotics may be considered for patients undergoing drainage of perianal abscess. Fistula-in-ano can be managed conservatively for one to three months. For a persisting fistula, fistulectomy with cryptotomy (when abnormal anal crypts are found) is the preferred treatment.