IT could be a boil in the skin surrounding tha anus.Boil or furuncle is a skin disease caused by the infection of hair follicles, thus resulting in the localized accumulation of pus and dead tissue.
The symptoms of boils are red, pus-filled lumps that are tender, warm, and/or painful. A yellow or white point at the center of the lump can be seen when the boil is ready to drain or discharge pus.
Boils are generally caused by an infection of the hair follicles by Staphylococcus aureus, a strain of bacterium that normally lives on the skin surface. It is thought that a tiny cut of the skin allows this bacterium to enter the follicles and cause an infection.
Most boils run their course within 4 to 10 days.
Once the boil drains, the area should be washed with antibacterial soap and bandaged well. The maturing process may be accelerated by applying Ichthammol-based salve.