Efficacy of Platelet-rich Plasma on Perianal Wound Healing After Anal Fistulotomy: A Randomized Controlled Clinical Trial

Fistula-in-ano is an epithelial-lined tract connecting the anal canal to the perianal skin. Most commonly, it affects people in the third to fifth decades of life.

Anal fistula arise spontaneously, when it is referred to as idiopathic or cryptoglandular, or as a result of an underlying pathology, such as inflammatory bowel disease, malignancy, trauma or irradiation.

The majority of anal fistula often occurs following anorectal abscess. An anorectal abscess occurs when an anal gland becomes obstructed, resulting in infection and abscess formation. One-third of patients undergoing incision and drainage of an anorectal abscess will later develop a fistula. Thirty to 70% of patients diagnosed with an anorectal abscess will already have a fistula present on exam.

According to the relation of fistulous track to the sphincter complex, anal fistulas can be classified as simple or complex. Simple anal fistula includes low transsphincteric and intersphincteric fistulas that cross less than 30% of the external sphincter fibers. On the other hand, complex anal fistulas comprise, high transsphincteric fistulas, suprasphincteric, extrasphincteric fistulas, and horseshoe fistulas.

Patients with anal fistula often complain of perianal cellulitis, anorectal pain, pruritus ani, smelly or bloody drainage of pus, and in some cases difficulty controlling bowel movements.