An anal or rectal abscess is an infected cavity filled with pus found near the anus or rectum. Abscesses cause pain, swelling and sometimes a fever. About 50% of abscesses become a fistula (a small tunnel from the rectum to the skin near the anus).
Swelling around the anus and a constant, throbbing pain are the most common symptoms. Pain with bowel movements may be severe.
Other symptoms may include:
- Discharge of pus from the rectum
- Fatigue and general malaise
- Fever, night sweats, and chills
- Lump or nodule
- Swollen, red, tender at edge of anus
- Painful, hardened tissue
Treatment of anal abscess usually requires surgical drainage, which can often be done in the office. Sometimes drainage in the operating room using a general anesthetic is required for deeper abscesses. Antibiotics are sometimes used in the treatment of anal abscesses.
About 50% of persons having an anal abscess will develop an anal fistula.ASCRS: Anal Abcess/Fistula