Anal Fistula

A fistula is a tiny channel or tract that develops in the presence of inflammation and infection. It may or may not be associated with certain illnesses such as Crohn's disease. The channel usually runs from the rectum to an opening in the skin around the anus. However, sometimes the fistula opening develops elsewhere. In women with Crohn's disease or obstetric injuries, the fistula could open into the vagina or bladder.

Since fistulas are infected channels, there is usually some drainage. Often a draining fistula is not painful, but it can irritate the skin around it.

Diagnosis of an abscess is usually made on examination of the area. If it is near the anus, there is always pain, and often redness and swelling. Our physicians will look for an opening in the skin (a sign that a fistula has developed), and try to determine the depth and direction of the channel or tract of the fistula. However, signs of fistula may not be present on the skin's surface around the anus. In this case, we use an instrument called an anoscope to see inside the anal canal and lower rectum.

Whenever we find an anal fistula, further tests are needed to be sure Crohn's disease is not present. Blood tests, X-rays, and a colonoscopy are often required. 

Treatment of anal fistula often varies, depending on whether Crohn's disease is present. If it is, then prolonged treatment with a variety of medications, including antibiotics, is usually undertaken. Often these medications will cure the infection and heal the fistula.

If Crohn's disease is not present, it still may be worthwhile to try a course of antibiotics. If these do not work, surgery is usually very effective. Most of the time, fistula surgery is done on an outpatient basis or with a short hospital stay.