A Case of Anal Fistula Which Has an External Opening in Thigh

In, Seung Hyun; Lee, Heung Woo; Nam, Young Soo; Lee, Kwang Soo

Abstract

Infection of the anal glands is the most common cause of anorectal abscess. Ductal obstruction may result in stasis, infection, and abscess formation. Drainage of the abscess through the perianal skin, whether spontaneous or operative, may lead to a fistula. the fistula in the fascial or fatty planes, especially within the intersphincteric space, located between the internal and the external sphincter extending into the ischiorectal fascia. Fistulas are usually divided into four main anatomic categories as described by Parks and colleagues in 1976.(1,2) The most commonly occurring is the intersphincteric fistula, constituting 70% of all anal fistulas. The infectious process starting from its origin passes directly downward to the anal margin, but there are some variants of these type of fistulas that are less common and more complex to treat. Transsphincteric (25%), suprasphincteric (4%), and extrasphincteric (1%) fistulas constitute the remaining 30% of other anal fistulas those are not intersphincteric. Extrasphincteric fistula is rare and difficult to treat. It begins from the perineal skin penetrating directly downward to the rectal wall above the levator ani. The tract it forms is completely outside the sphincteric apparatus. There are numerous causes to anal fistulas, including trauma, carcinoma, and Crohn's disease. We report a rare case of a 46 year old male patient with anal fistula which has a long abnormal course and an external opening in thigh. The patient suffered from pain on the external opening for 3 years, with dirty discharge.