Guidelines for treating acne.

Acne, a chronic inflammatory disease of the pilosebaceous units of the face, neck, chest, and back, is the most common skin disorder occurring universally, with an estimated prevalence of 70-87%.(1) It is a pleomorphic disorder characterized by both inflammatory (papules, pustules, nodules) and noninflammatory (comedones, open and closed) lesions. Grading of acne is mandatory to determine the appropriate therapeutic strategy. Mild acne can be purely comedonal or mild papulopustular, with a few papulopustules present as well.(2) Moderate acne is characterized by numerous comedones, few to many pustules, and few small nodules, with no residual scarring.(2) In severe acne papulopustules are numerous, many nodules can be detected, inflammation is marked, and scarring is present.(2) Very severe acne can be recognized by sinus tracts, grouped comedones, many deeply located nodules, and severe inflammation and scarring.(2) Although acne does not affect health overall, its impact on emotional well-being and function can be critical and is often associated with depression, anxiety, and higher-than-average unemployment rates.(3) Effective treatment can dramatically improve a person's quality of life.