Symptoms of an anal fistula can include:
The end of the fistula might be visible as a hole in the skin near your anus, although this may be difficult for you to see yourself.
See your GP if you have persistent symptoms of an anal fistula. They'll ask about your symptoms and whether you have any bowel conditions.
They may also ask to examine your anus and gently insert a finger inside it (rectal examination) to check for signs of a fistula.
If your GP thinks you might have a fistula, they can refer you to a specialist called a colorectal surgeon for further tests to confirm the diagnosis and determine the most suitable treatment.
These may include:
Most anal fistulas develop after an anal abscess. They can occur if the abscess doesn't heal properly after the pus has drained away.
It's estimated that between one in every two to four people with an anal abscess will develop a fistula.
Less common causes of anal fistulas include:
Anal fistulas usually require surgery as they rarely heal if left untreated.
The main options include:
All these procedures have different benefits and risks. You can discuss this with your surgeon.
Many people don't need to stay in hospital overnight after surgery, although some may need to stay in hospital for a few days.
Read more about treating an anal fistula.