Acne vulgaris is one of the most common skin disorder affecting susceptible hair follicles, most commonly found on the neck, upper trunk, and face. It is described by comedones (which are primary lesions of acne) that are both open and closed, and by cysts, nodules, pustules, and papules.
Acne is one of the most frequently encountered skin diseases in adolescents. Both genders are affected equally, but onset in girls is a little earlier. This may be because girls reach puberty at a younger age than boys. Acne is more noticeable during adolescence because the endocrine glands that influence the sebaceous glands (responsible for secretion of sebum or oil) are on their highest performance. Acne seems to have stemmed from the interaction of hormonal, bacterial, and genetic factors.
During childhood, the sebaceous glands are small and virtually nonfunctioning. These glands are under endocrine control, especially by the androgens. During puberty, androgens stimulate the sebaceous glands, causing them to enlarge and secrete natural oil called sebum, which rises to the top of the hair follicle and flows out onto the skin surface. In adolescents who develop acne, androgenic stimulation produces a heightened response in the sebaceous glands so that acne occurs when accumulated sebum plugs the pilosebaceuos ducts. This accumulated material forms comedones.
The primary lesions of acne are comedones. Closed comedones (whiteheads) are obstructive lesions formed from impacted lipids or oils and keratin that plug the dilated follicle. They are small, whitish papules with minute follicular openings that generally cannot be seen. These closed comedones may evolve into open comedones, in which the contents of the ducts are in open communication with the external environment. The color of open comedones (blackheads) results not from dirt, but from an accumulation of lipid, bacterial, and epithelial debris.
Although the exact cause is unknown, some closed comedones may rupture, resulting in an inflammatory reaction caused by leakage of follicular contents (e.g., sebum, keratin, bacteria) into the dermis. This inflammatory response may result form the action of certain bacteria, such as proprionibacterium acnes, that live in the hair follicles and break down the triglycerides of the sebum into free fatty acids and glycerin. The resultant inflammation is seen clinically as erythematous papules, inflammatory pustules, and inflammatory cysts. Mild papules and cysts drain and heal on their own without treatment. Deeper papules and cysts may result in scarring of the skin. Acne is usually graded as mild, moderate, or severe, based on the number and type of lesions (e.g., comedones, papules, pustules, cysts).
Acne oftentimes leaves behind small scars in the skin. Acne has different types, according to its shape or form. Ice pick scars are described as deep pits shaped like inverted volcanoes. Box car scars, as the name imply, are shaped like boxes or angular shapes. Rolling scars appear like waves, while hypertrophic scars are keloid or thickened scars.
The goals of management of acne are to reduce bacterial colonies, decrease sebaceous gland activity, prevent the follicles from becoming plugged, reduce inflammation, combat secondary infection, minimize scarring, and eliminate factors that predispose the person to acne. The therapeutic regimen depends on the type of lesion.
There is no predictable cure for acne vulgaris, but combinations of therapies are available that can effectively control its activity.