An anal fistula is a small tunnel that connects an abscess, an infected cavity in the anus, to an opening on the skin around the anus.
The anus is the external opening through which feces are expelled from the body. Just inside the anus are a number of small glands that make mucus. Occasionally, these glands get clogged and can become infected, leading to an abscess. About half of these abscesses may develop into a fistula.
Fistula Tests and Investigations
What are the symptoms of an anal fistula?
The signs and symptoms of an anal fistula include:
Frequent anal abscesses
Pain and swelling around the anus
Bloody or foul-smelling drainage (pus) from an opening around the anus. The pain may decrease after the fistula drains.
Irritation of the skin around the anus from drainage
Pain with bowel movements
Fever, chills, and a general feeling of fatigue