What causes anal abscess?

Possibly a: Tear can occur in the lining of the intestine near the anal opening. Could be from injury or straining with constipation. Can rarely be associated with crohn's disease. Infection builds up inside and works itself toward the outside causing painful red swelling externally, outside the anal opening.

Multiple causes: An anal abscess can have many different causes. These include: - Infection of an anal fistula. An anal fistula is a small superficial tear in the skin of the anal canal. -Sexually transmitted infections. Blocked anal glands. Risk factors for anal abscesses include: Colitis Inflammatory bowel disease such as Crohn's disease or ulcerative colitis Diabetes Diverticulitis Pelvic inflammatory disea