Furuncle following staph infection
At first it was a small pustule with a hair coming out of it but rapidly enlarged and became painful. This is a furuncle due to staph infection of a hair follicle. The pustule forms in the opening or infundibulum of the hair follicle but then progresses to involve the rest of the follicle and may rupture under the skin. If several furuncles form, the lesion is known as a carbuncle.