Anorectal Fistula

Anorectal fistula (also known as fistula-in-ano) is an abnormal passage connecting the anus or rectum to the skin surface; or, less commonly, another organ.

Causes

Anorectal fistulae are often associated with anorectal abscesses. In other cases, they are linked to patients of:

·         Tuberculosis;

·         Crohn’s disease – a form of inflammatory bowel disease;

·         Cancer;

·         Diverticulitis – inflammation along the inner lining of the intestine; and

·         Injury to the anus or rectum.

Disease pathway

The majority of fistulae start as a large gland in the wall of the anus or rectum; often occurring after an anorectal abscess of the gland has been drained.

Prolonged presence of fluid within the gland prevents the cavity from closing, resulting in the formation of the fistula.

Symptoms and diagnosis

Anorectal fistulae can present with a number of symptoms, including:

·         Pain in the anal region;

·         Discharge – especially when the fistula has become infected;

·         Itching; and

·         Body-wide symptoms of infection, such as fever, headaches, etc.

Upon physical examination, one or more openings of the fistula are usually visible to the doctor, or at least palpable beneath the skin. The doctor may insert a probe to gauge its direction and depth.

Treatment

There are a number of surgical options available to treat anorectal fistulae. The suitability of each will depend on the location of the fistula; its size; and the cause. For many of the methods, however, a scar is likely to remain.