Colon and Rectal Surgeons
of Kansas City

Fistula

An anal fistula is a common infection that usually begins from an infected gland within the anal canal. The gland eventually bursts through the soft tissues and creates a pocket of infection or an abscess which eventually bursts through the skin or is subsequently drained. Fifty percent of the time there is a significant amount of inflammation and swelling that destroys the connection to the anal canal. The other 50% will form a chronic infection or a fistula. A fistula is a connection from the anal canal to the outside of the anal area. Anal infections can also be caused by infected fissures or Crohn's disease. However, the most common cause is that of an infected gland.

If a fistula is present, it rarely resolves without a minor surgical procedure. The most common and effective way to repair an anal fistula is by opening the tract from the exit site to the entrance site. This is called a fistulotomy. Occasionally if there is a significant amount of sphincter muscle involved, a small Silastic drainage tube or a suture of silk will be placed to achieve adequate drainage for a second stage of an operation. This is usually fairly uncommon.

A fistula repair is usually performed on an outpatient basis and is not significantly painful after surgery. One should take a Fleets enema at least one hour prior to coming in for surgery. Occasionally one may need to spend an overnight at the hospital to be discharged the next day.

It is recommended to avoid exercise for at least four weeks. After surgery there will be an open wound in the anal area, usually surrounded by dissolvable stitches to ensure that the wounds heal from the bottom outward, similar to a skinned knee healing. These wounds take approximately 6 to 8 weeks to heal completely. Expect occasional mild bleeding and discharge until it is entirely healed. Hot baths 3 to 4 times a day would be beneficial. After bowel movements it is recommended to shower or irrigate the bottom area off with water. Keeping the wound dry if possible would be recommended by using a gauze pad next to the wound at night and during the day. A high fiber diet with the use of fiber additives such as Konsyl also would be recommended. Pain medication should be taken on an as needed basis. One may also wish to use a topical anesthetic such as Xylocaine. Discontinue the Xylocaine if it causes discomfort. A return office visit in approximately three weeks would be recommended. One should call sooner if there are any significant problems such as severe uncontrolled pain, fever, difficulty with urination, or excess bleeding. Also call if there are problems with diarrhea or constipation.

Recurrence rate of anal fistulas is uncommon after surgery and is approximately 5% or lower. A colonoscopy occasionally may be needed to rule out the possibility of Crohn's disease which is an auto-immune disease affecting the GI tract which many times initially presents with rectal abscesses and fistulas.

For more information please visit:
The American Board of Colon and Rectal Surgeons
http://www.fascrs.org