The term anal fistula refers to a channel that forms as a result of an abscess in the anus. An anal abscess forms when small glands inside the anus become infected. The abscess fills with pus and infected fluid and, if not taken care of, the abscess becomes re-infected or bursts forming a fistula. According to England’s National Health Services, you are more likely to develop an anal fistula if you suffer from any of the following conditions that cause inflammation of the intestines:
Irritable bowel syndrome
Treating the Abscess
Symptoms of an anal abscess are usually mild and include anal itching and pus drainage. Abscesses can usually be treated with a course of antibiotics. A larger abscess will have to be drained to get all of the infected fluid out. According to England’s National Health Services, half of all people who experience an anal abscess will go on to develop a fistula. An anal abscess that doesn’t heal and repeatedly becomes infected will require more aggressive treatment.
Treating the Fistula
An anal abscess that doesn’t heal forms a channel or track under the sphincter muscles. According to the Mayo Clinic, a recurring anal abscess with drainage is a clue that a person may have an anal fistula. Symptoms include an external opening that is red, inflamed, and oozes pus, sometimes mixed with blood. The most common treatment for an anal fistula is an operation to open up that channel and clean out any drainage and remaining abscess. This operation is called a fistulotomy. Another procedure involves placing a seton—a rubber band-like string—on the sphincter muscle allowing it to be cut very slowly over a period of several weeks. According to the Mayo Clinic, the goal of these treatments is to cure the fistula with as little impact as possible on the sphincter muscles. Less invasive options include using a protein plasma glue or collagen plug to fill the fistula after the surgeon has cleaned it out. These procedures inhibit the return of the abscess and fistula.