Anal Abscess

What is an Anal Abscess?

An anal abscess is a collection of pus that develops in the tissues around the anus.

What is the Cause of an Anal Abscess?

A number of small glands are normally present between the inner and outer layers of the anal sphincter muscle. Bacteria may lodge in these glands, causing infection and an abscess. This may extend to various areas around the anal canal to involve the anal sphincter muscle and surrounding structures. The abscess may enlarge and burst through the overlying skin or may be aspirated/drained by surgical treatment.

What are the Symptoms of Abscess?

As the amount of pus in an abscess increases, the pressure within it rises. This produces a throbbing pain. Other symptoms are fever and sweating.

How is an Abscess Treated?

The pus is drained from the abscess cavity by either needle aspiration or making an opening through the overlying skin. This may be done under local anaesthesia in the doctor's office. A large abscess may require wider drainage, under general anaesthesic. Antibiotics may be used to control the spread of the infection, but antibiotics alone will not cure an abscess. 




What is a Fistula?

An anal fistula is an abnormal track ("tunnel") between the internal lining of the anus and the skin outside the anus. A fistula may develop after drainage of an anal abscess or spontaneously. Discharge of pus may be constant or intermittent as the external opening on the skin may heal temporarily.

Is a Fistula Related to Other Diseases?

Most fistulae are the result of infections in an anal gland. However patients suffering from inflammatory bowel disease (colitis and crohn's disease) are more likely to develop anal abscesses and fistulae.

How is A Fistula Treated?

Surgery is needed to cure a fistula. The course of the track between the anus and the skin has to be identified and exposed. This track may be treated in one of three ways according to its complexity:

  • Seton: is a loop of flexible material placed along the track to maintain drainage for a period of time, allowing healing and assists with reducing the size of the fistula.

  • Fistulotomy: opens the length of the track to the skin's surface allowing the open wound to heal slowly.

  • Fistula repair: closes the internal opening of the track and preserves anal sphincter muscle.