Incision and drainage of perianal abscess with or without treatment of anal fistula.

The perianal abscess is a common surgical problem. A third of perianal abscesses may manifest a fistula-in-ano which increases the risk of abscess recurrence requiring repeat surgical drainage. Treating the fistula at the same time as incision and drainage of the abscess may reduce the likelihood of recurrent abscess and the need for repeat surgery. However, this could affect sphincter function in some patients who may not have later developed a fistula-in-ano.