An anal abscess is a pus-filled pocket located in the spaces around the anus and rectum. An abscess can be found near the surface of the anal opening or deeper in the rectum.



An anal abscess is caused by a bacterial infection. Infection may occur when there is a blockage in one or more of the anal glands that secrete mucous or fistula tract in the anus or rectum.

Anal Abscess  
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Risk Factors  

Anal absesses are more common in men. Other factors that may increase your chance of developing an anal abscess include:

  • Certain conditions, such as Crohn's disease, ulcerative colitis, or sexually transmitted diseases
  • Receptive anal intercourse
  • Medications that suppress the immune system
  • Pregnancy


Symptoms depend on where the abscess is located. An anal abscess may cause:

  • Pain and tenderness radiating from the location of the abscess if it is near the surface
  • Lower abdominal pain if it is located deeper in the rectum
  • Redness and swelling—visible with a surface abscess; also occurs in a deep abscess, but cannot be seen
  • Pus drainage
  • Fever

Complications of an anal abscess may include:

  • Anal fistula—abnormal channel between the rectum and the surface of the anal skin leading to the outside
  • Systemic sepsis—serious, life-threatening infection that spreads throughout the body
  • Stool incontinence