Acne vulgaris is a common disorder affecting the skin. It specifically involves the pilosebaceous unit, consisting of the hair follicle and sebaceous gland. The cause is multifactorial and the four major causal components are proliferation of the bacteria Propionibacterium acnes, abnormal shedding of the cells lining the pores, androgen-induced sebum production, and inflammation. It primarily affects teenagers but is not confined to this age group. The lesion types in acne are divided into two major groups, inflammatory and noninflammatory. Noninflammatory lesions include open and closed comedones, also known as whiteheads and blackheads, respectively. Inflammatory lesions are more prominent, appearing as red papules, pustules, or, the most severe, cysts. Acne predominates in areas rich in sebaceous glands such as the face, chest, and upper back. Although acne does not constitute a life-threatening condition, multiple studies have demonstrated that the psychosocial ramifications of this highly visible condition occurring during the formative teenage years can seriously impact self-esteem and quality of life.
Multiple categories of drugs have proven efficacy in the treatment of acne. Awareness of the multifactorial pathogenesis of acne has facilitated the rational application of combination therapies with different mechanisms of action. Milder cases of acne are generally treated with topical products including benzoyl peroxide, antibiotics, and vitamin A derivatives. The side effects of topical products are generally limited to local irritation or drying of the skin. In more severe cases, systemic antibiotics are used in combination with the topical agents. The most commonly prescribed systemic antibiotics are in the tetracycline class including tetracycline, doxycycline, or minocycline. An increasing prevalence of Propionibacterium acnes resistance to the usual antibiotics used to treat acne is being seen, and the treatment period should be kept as brief as possible for this reason. For the most severe cases of acne, a systemic retinoid, isotretinoin, may be prescribed. All of the systemic drugs are associated with various side effects necessitating proper patient selection and counseling before starting the medication and careful monitoring during the treatment course.
Adult female acne is significantly influenced by the effect of androgens on the pilosebaceous unit. An index of suspicion for overproduction of androgens from the adrenal glands or ovaries must be considered, but in the majority of patients hormone levels are normal and there appears to be a peripheral alteration whereby the sebaceous gland is more sensitive to normal circulating androgen levels. Acne in this population is particularly challenging to treat because it tends not to respond to the traditional therapies employed in teenage patients. Efficacious treatments such as oral contraceptives, some of which are now approved by the Food and Drug Administration for the treatment of acne, and antiandrogens, none of which are approved for this indication, alter the hormonal milieu of the pilosebaceous unit.
The most important aspect of acne treatment is patient compliance with medications. Contrary to popular belief, particular foods are not implicated in the development of acne. However, the Western diet, high in sugar and refined carbohydrates, may have an adverse effect on acne. Poor hygiene is also not a significant factor in acne and, in fact, overzealous cleansing can worsen the irritation. In most cases, the acne is self-limited peaking in severity during the teenage years and eventually remitting. The presence or absence of acne in teenage girls is not predictive of who will go on to develop the adult female variety. Early and appropriate treatment will reduce the likelihood of long-term scarring as will avoidance of manipulating the lesions.