An Anal Fistula is almost always the result of a previous anal abscess, which is an infected cavity filled with pus found near the anus or rectum. Anal Abscesses form when small glands located just inside the anus get clogged and become infected. A fistula is a small tunnel that forms under the skin and connects a previously infected anal gland to the skin on the buttocks outside the anus. Certain conditions – colitis or other inflammatory conditions of the intestine – can sometimes make these infections more likely.
How an Anal Fistula Forms
Anal Fistula formation occurs after a peri-anal abscess has been drained. The fistulous tract may persist connecting the anal gland from which the abscess arose to the skin. If this occurs, persistent drainage from the outside opening may indicate the persistence of this tunnel. If the outside opening of the tunnel heals, recurrent abscess may develop.
An abscess is usually associated with symptoms of pain and swelling around the anus. Individuals may also experience fatigue, fevers and chills. Symptoms related to an anal fistula include irritation of skin around the anus, drainage of pus (which often relieves the pain), fever, and feeling poorly in general.
Anal Abscesses do not always lead to anal fistula formation. A fistula develops in about 50 percent of all abscess cases, and there is really no way to predict if this will occur.
Anal Abscess and Fistula Treatment
An abscess is treated by making an opening in the skin near the anus to drain the pus from the infected cavity and thereby relieve the pressure. Often, this can be done in the office using a local anesthetic. A large or deep abscess may require hospitalization and drainage under anesthesia. Hospitalization may also be necessary for patients prone to more serious infections, such as diabetics or people with decreased immunity. Antibiotics are a poor alternative to draining the pus, because antibiotics do not penetrate the fluid within an abscess effectively enough.
Surgery is necessary to cure an anal fistula. Fistula surgery usually involves opening up the fistula tunnel. Often this will require cutting a small portion of the anal sphincter, the muscle that helps to control bowel movements. Joining the external and internal openings of the tunnel and converting it to a groove will then allow it to heal from the inside out. Most of the time, fistula surgery can be performed on an outpatient basis.
Whats Happens After Anal Fistula Surgery
Discomfort after fistula surgery can be mild to moderate for the first week and can be controlled with pain pills. The amount of time lost from work or school is usually minimal. Soaking the affected area in warm water (sitz bath) is recommended two or three times a day. Stool softeners or a bulk fiber laxative may also be recommended. It may be necessary to wear a gauze pad or mini-pad to prevent the drainage from soiling clothes. Bowel movements will not affect healing.