Furuncle on Buttock Pictures - 5 Photos & Images

Most boils are caused by a germ (staphylococcal bacteria). This germ enters the body through tiny nicks or cuts in the skin or can travel down the hair to the follicle. These health problems make people more susceptible to skin infections:
Diabetes
Problems with the immune system
Poor nutrition
Poor hygiene
Exposure to harsh chemicals that irritate the skin

A boil starts as a hard, red, painful lump usually about half an inch in size. Over the next few days, the lump becomes softer, larger, and more painful. Soon a pocket of pus forms on the top of the boil. These are the signs of a severe infection:
The skin around the boil becomes infected. It turns red, painful, warm, and swollen.
More boils may appear around the original one.
A fever may develop.
Lymph nodes may become swollen.