Recurrent anal fistulas: When, why, and how to manage?

Table 1 Risk factors for persistence/recurrence of anal fistula

Type	Risk factors for recurrence
Preoperative	Position of the tract (high trans-sphincteric, suprasphincteric, and extrasphincteric)
	Curved fistula tracts (horse-shoe and semi horse-shoe fistulas)
	Secondary extensions (supralevator, infralevator, or ischeoanal)
	Secondary anal fistula to Crohn’s disease
	Diabetes mellitus
	Steroids and immunosuppressive drugs
	Previous fistula surgery
Intraoperative	Wrong selection of the procedure
	Failure to identify the internal opening
	Failure to extirpate the primary tract completely
	Missed secondary tracts and abscess cavities
Postoperative	Poor hygiene of the anal wound
	Failure to comply to follow-up instructions
	Persistence of preoperative factors