Most fistulas begin as anorectal abscesses. When the abscess opens spontaneously into the anal canal (or has been opened surgically), a fistula may occur. Approximately, 8-50% of perianal abscess patients end up having an anal fistula.
- An anal fistula may also develop as a result of:
- A growth or ulcer (painful sore)
- A complication of surgery
- A health problem you were born with
Other infections or conditions that can lead to the development of an anal fistula include:-
- Cancer of the rectum:- The rectum is an area at the end of the colon where faeces are stored.
- Tuberculosis (TB):- A bacterial infection that mainly affects the lungs, but can also spread to many different parts of the body.
- HIV and AIDS:- A virus that attacks the body’s immune system (its defence against disease and infection)
- Syphilis :- A bacterial infection that is passed on through sexual contact, injecting drugs or blood transfusions.
- Chlamydia:- A sexually transmitted infection that often causes no symptoms.
Symptoms of fistulas
- Pain, which is usually constant, throbbing and worse when sitting down
- Skin irritation around the anus, including swelling, redness and tenderness
- Discharge of pus or blood
- Constipation or pain associated with bowel movements