Fistula Causes

Anal fistula usually occurs from an injury to the tissue lining the anal canal or by an infection in that area.


An anal fistula begins with inflammation of the mucous lining of the rectum. The area then becomes an abscess as it is constantly infected by feces; eventually a fistula breaks through to the skin near the anus. Abscesses can recur if the fistula seals over, allowing the accumulation of pus. Anal fistulas are very painful and uncomfortable because of the pus-drain.

Anal Fistula may occur as a result of –

  • Constipation causing injury
  • Infection in the anal glands lining the anal canal
  • Crohn’s disease, chronic inflammation of the intestines
  • Abscess of the large intestine