Acne vulgaris (or simply acne) is a chronic skin condition characterized by areas of blackheads, whiteheads, pimples, greasy skin, and possibly scarring. The resulting appearance may lead to anxiety, reduced self-esteem, and in extreme cases, depression or thoughts of suicide.
Genetics is estimated to be the cause of 80% of cases. The role of diet as a cause is unclear. Neither cleanliness nor sunlight appear to be involved. However, cigarette smoking does increase the risk of developing acne and worsens its severity. Acne mostly affects skin with a greater number of oil glands including the face, upper part of the chest, and back. During puberty in both sexes, acne is often brought on by an increase in androgens such as testosterone.
Acne occurs most commonly during adolescence, affecting an estimated 80–90% of teenagers in the Western world. Lower rates are reported in some rural societies. In 2010,acne was estimated to affect 650 million people globally making it the 8th most common disease worldwide. People may also be affected before and after puberty. Though it becomes less common in adulthood than in adolescence, nearly half of people in their twenties and thirties continue to have acne. About 4% continue to have difficulties into their forties.
Signs and Symptoms
Typical features of acne include seborrhea (increased oil secretion), microcomedones, comedones, papules, pustules, nodules (large papules), and possibly scarring. The appearance of acne varies with skin color. It may result in psychological and social problems. Some of the large nodules were previously called cysts and the term nodulocystic has been used to describe severe cases of inflammatory acne.
In women, acne can be improved with the use of any combined oral contraceptive. The combinations that contain third or fourth generation progestins such as desogestrel, norgestimate, or drospirenone may theoretically be more beneficial. Antiandrogens such as cyproterone acetate and spironolactone have also been used successfully to treat acne.
Topical antibiotics are frequently used for mild to moderate severe acne. Oral antibiotics are indicated for moderate to severe cases of inflammatory acne and decrease acne due to their antimicrobial activity against P. acnes in conjunction with anti-inflammatory properties. They are believed to work both by decreasing the number of bacterial and as an anti-inflammatory.
Salicylic acid (category C) is a topically applied beta-hydroxy acid that possesses bacteriostatic and keratolytic properties. Additionally, salicylic acid opens obstructed skin pores and promotes shedding of epithelial skin cells. However, salicylic acid is known to be less effective than retinoid therapy.
Isotretinoin is very effective for severe acne as well as moderate acne refractory to other treatments. Improvement is typically seen after one to two months of use. After a single course, about 80% of people report an improvement with more than 50% reporting complete remission.