Alternate Names : Perirectal Abscess, Perianal Abscess
An anorectal abscess is a pocket of pus that forms in the anus and/or the area just above it, called the rectum.
What is going on in the body?
Most anorectal abscesses begin as bacterial infections of the glands in the anus that produce mucus. Infection can cause inflammation. Inflammation creates a wall around the bacteria and forms an abscess. This protective wall makes it hard for the immune system to fight the bacteria.
What are the causes and risks of the condition?
Most anorectal abscesses are caused by bacterial infection in the lining of the anus or rectum. Factors that increase a person's risk for an abscess include:
inflammatory bowel diseases, including Crohn disease and ulcerative colitis
immunodeficiency disorders, such as HIV