A patient who feels ill and complains of chills, fever and pain in the rectum or anus could be suffering from an anal abscess or fistula.
What is an anal abscess?
An anal abscess is an infected cavity filled with pus found near the anus or rectum.
What causes an abscess?
An abscess results from an acute infection of a small gland just inside the anus, when bacteria or foreign matter enters the tissue through the gland.
Just inside the anus are a number of small glands. If one of these glands become blocked, an abscess—an infected cavity—may form. An anal abscess is usually treated by surgical drainage, although some drain spontaneously. About 50% of these abscesses may develop into a fistula, in which a small tunnel connects the infected gland inside the anus to an opening on the skin around the anus.
What causes a fistula?
After an abscess has been drained, a tunnel 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.
What are the symptoms of an abscess or fistula?
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 the fistula include irritation of skin around the anus, drainage of pus (which often relieves the pain), fever, and feeling poorly in general.
Does an abscess always become a fistula?
No. A fistula develops in about 50 percent of all abscess cases, and there is really no way to predict if this will occur.
How is an abscess treated?
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 doctor’s office using a local anesthetic. A large or deep abscess may require hospitalization and the assistance of an anesthesiologist. 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.
Surgery is necessary to cure an anal fistula. Although fistula surgery is usually relatively straightforward, the potential for complication exists. It may be performed at the same time as the abscess surgery, although fistulas often develop four to six weeks after an abscess is drained, sometimes even months or years later.
Fistula surgery usually involves opening up the fistula tunnel. Often this will require joining the external and internal openings of the tunnel by an incision (cut) 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. Treatment of a deep or extensive fistula may require a short hospital stay.
How long does it take before patients feel better?
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.
Treatment of an abscess or fistula is followed by a period of time at home, when soaking
the affected area in warm water (sitz bath) is recommended three or four 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.
What are the chances of a recurrence of an abscess or fistula?
If properly healed, the problem will usually not return.