Severe Acne

Acne is caused by an interaction between hormones, skin oils, and bacteria that results in inflammation of hair follicles. Acne occurs mostly on the face, upper chest, shoulders, and back and is characterized by pimples, cysts, and sometimes abscesses. Both cysts and abscesses are pus-filled pockets, but abscesses are somewhat larger and deeper.

Sebaceous glands, which secrete an oily substance (sebum), lie in the dermis, the middle layer of skin. These glands are attached to the hair follicles. The sebum, along with dead skin cells, passes up from the sebaceous gland and hair follicle and out to the surface of the skin through the pores.

Acne results when a collection of dried sebum, dead skin cells, and bacteria clog the hair follicles, blocking the sebum from leaving through the pores. If the blockage is incomplete, a blackhead (open comedone) develops; if the blockage is complete, a whitehead (closed comedone) develops. The blocked sebum-filled hair follicle promotes overgrowth of the bacteria Propionibacterium acnes, which are normally present in the hair follicle. These bacteria break down the sebum into substances that irritate the skin. The resulting inflammation and infection produce the skin eruptions that are commonly known as acne pimples. If the infection worsens, an abscess may form, which may rupture into the skin, creating even more inflammation.