Acne

Alternative names:

acne vulgaris; cystic acne; pimples

Definition:

An inflammatory skin condition characterized by superficial skin eruptions that are caused by plugging of the skin pores.

Causes, incidence, and risk factors:

Acne is most common in adolescent boys, but it can occur in both sexes and at all ages. There seems to be a familial tendency to develop acne. The condition usually begins at puberty and may continue for many years. Three out of four teenagers have acne to some extent, probably caused by hormonal changes that stimulate the sebaceous (oil producing) skin glands. Other hormonal changes, such as can occur with menstrual periods, pregnancy, use of birth control pills, or stress, also aggravate acne.

Acne is caused when sebaceous glands within the hair follicles (pores) of the skin become plugged, because secretion occurs faster than the oil and skin cells can exit the follicle. The plug causes the follicle to bulge (causing whiteheads), and the top of the plug may darken (causing blackheads). If the plug causes the wall of the follicle to rupture, the oil, dead skin cells, and bacteria found normally on the surface of the skin can enter the skin and form small infected areas called pustules (also known as pimples or "zits").

If these infected areas are deep in the skin, they may enlarge to form cysts. A sebaceous cyst forms when the sebaceous gland continues to produce oil. Instead of rupturing the follicle wall, the follicle continues to enlarge and form a soft, pliable lump (known as a cyst) under the skin. The cyst is usually not painful or discolored unless it becomes infected. Acne commonly appears on the face and shoulders, but may extend to the trunk, arms and legs.

Acne is not caused by dirt or by masturbation or other activities, but dirt and oil on the face can aggravate the condition. Other factors that increase the chances of acne are hormonal changes, exposure to weather extremes, stress, oily skin, endocrine disorders, certain tumors, and the use of certain drugs (such as cortisone, testosterone, estrogen, and others). Acne is not contagious. A tendency to have acne may persist through ages 30's to early 40's.