Acne

Key Points
*Acne is a disorder of the pilosebaceous unit, which is composed of a hair follicle and associated oil gland. The follicular opening becomes clogged with a plug containing dead skin cells and oil. The occluded follicle then becomes inflamed, likely due to the activity of a bacteria known as P. acnes.

Clinical features are well known and include whiteheads (closed comedones), blackheads (open comedones), inflamed red papules and pustules, and occasionally deeper cysts or nodules

Factors leading to the development of acne include: 
     -Androgen hormone activity causing overactive sebaceous glands with resultant  increased oil        production
     -Comedone (pore blockage) formation, which is affected strongly by genetic factors
     -Overgrowth of  P. acnes bacteria

Commonly appears on the face and shoulders

Most common in teenagers, but can occur at any age.  The higher levels of sex hormones during puberty are the initiating factor leading to increased sebum (oil) production.

Acne is a very common skin condition in which pores become clogged with sebum (oil) and keratin (skin cell components).  This is most often triggered by an increase in the production of sex hormones during puberty. However, acne may occur at any age.  The plugged pores (comedones) are more prone to overgrowth of the skin bacteria, P. acnes, which will often result in an inflammatory response within the follicle. This leads to the develoment of papules, pustules, nodules or cysts.   Acne often runs in  families and may be triggered by hormonal changes related to menstruation, pregnancy, birth control or stress.  Acne may be triggered by the use of oily cosmetic products, the use of certain drugs including steroids, hormone replacements, and phenytoin, or being exposed to high levels of humidity and sweating.

The blockage of the pore, called the plug or comedone, can manifest in several different ways. It may appear light (whitehead) or dark (blackhead). If the plug ruptures, the material inside may spread to the surrounding skin, causing it to become inflamed. Inflammation deep in the skin tissue can lead to the formation of cysts. Acne can also lead to facial scarring or changes in skin color.