An abscess is a localized pocket of pus caused by infection from bacteria. Certain conditions, such as Crohn’s disease can increase the risk of abscess in and around the anal canal. Patients with conditions that reduce the body’s immunity, such as cancer or AIDS, are also more likely to develop anal abscesses.

 

An abscess causes tenderness, swelling, and pain. These symptoms clear when the abscess is drained. The patient may also complain of fever, chills, and general weakness or fatigue.

 

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 an abscess, but like abscesses, certain illnesses such as Crohn’s disease can cause fistulas to develop. The channel usually runs from the rectum to an opening in the skin around the anus. However, sometimes the fistula opening develops elsewhere. For example, 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. An abscess and fistula often occur together. If the opening of the fistula seals over before the fistula is cured, an abscess may develop behind it.

 

Diagnosis:

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. The physician will look for an opening in the skin and try to determine the depth and direction of the channel or tract of the fistula. Signs of fistula and abscess may not be present on the skin’s surface around the anus so the doctor will use an instrument called an anoscope to see inside the anal canal and lower rectum.

 

Whenever the physician finds an abscess or fistula, further tests may be needed to be sure Crohn’s disease is not present.

 

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Treatment for Anal Abscess

An abscess must be surgically opened to promote drainage and relieve pressure. This is often done in the physician’s office under local anesthesia. Patients with a large or deep abscess, or those who have other conditions, such as diabetes, may be admitted to the hospital for the procedure. Antibiotics are usually prescribed along with surgical drainage, especially if the patient has other serious diseases, such as diabetes.

 

Treatment for Anal Fistula

Treatment of anal fistula depends 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, a course of antibiotics may still be recommened. If these do not work, surgery is usually very effective. The surgeon opens the fistula channel so that healing occurs from the inside out. Sometimes drains, called setons or mushroom catheters, are placed.  Most of the time, fistula surgery is done on an outpatient basis or with a short hospital stay. Following surgery, there may be mild to moderate discomfort for a few days, but patients usually have a short recovery period.