Anal Abscess is one of the most common types of diseases related to anus and anal canal in which a localized collection of pus develops in the underlying tissues of anus. Anal Abscess is a painful condition that may also lead to an Anal Fistula, which is a small infected channel that abnormally develops and connects the site of Abscess and the skin. It has been observed that around 50% of patients develop Anal Fistula along with Anal Abscess and this is can be a cause bleeding when passing stool. A fistula is a small tunnel that makes an abnormal connection between the site of the abscess and the skin.
In some cases, an anal fistula causes persistent drainage. In other cases, where the outside of the tunnel opening closes, the result may be recurrent anal abscesses.
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.
Some other risk factors for anal abscesses include:
• Ulcerative colitis and Crohn’s disease, which are inflammatory bowel diseases
• Medication such as chemotherapy drugs or prednisone or corticosteroid medicines
• HIV or AIDS or other diseases associated with the immune system
• Tearing of the lining between peri-anal skin and anal canal can cause anal abscess
• Ruptured anal haematoma can also be a cause for Anal Abscess
• Dorsal fissure
• Stricture of sigmoid colon
• Acute appendicitis
• Pelvic infection
Toddlers or children that have a history of anal fissures (tears in the anal sphincter) are also at a higher risk for developing anal abscesses later on. Such anal fissures might occur in children who have a history of constipation.