An anal or perirectal abscess is the accumulation of pus in the tissue surrounding the anus or rectum. It usually originates in an anal gland that becomes plugged and infected by bacteria. As the abscess enlarges you will typically experience pain, chills, fever, swelling, or drainage of blood or mucus. Left untreated, it could lead to anal stricture (constriction in the anal opening) causing difficulty with bowel movements, or a fistula (abnormal passage between the abscess, and anal skin or canal). Anal or perirectal abscesses are usually treated early by incision and drainage to prevent further tissue damage and control infection.
Superficial abscesses that are easily accessible are treated in the office or emergency room under local anaesthesia and sedation. An incision is made over the abscess close to the anus; the pus is drained and sent to the laboratory to be cultured. Larger or deeper abscesses require extensive exploration and debridement, and treatment is best performed in the operating room under general or regional anaesthesia. A drainage catheter may be placed, or the overlying skin excised to prevent recurrence.
Following the procedure, you may be prescribed pain medication and antibiotics to keep you comfortable and prevent further infection. Stool softeners are recommended to prevent constipation and straining. There may be some bleeding and drainage for a few days which is normal. You are recommended to soak the area in warm water 3 to 4 times a day, and follow up with your doctor in 2 to 3 weeks to check your surgical wound and assess for development of a fistula.