Acne Vulgaris

SOURCE

Source: Sibbald D. Acne vulgaris. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. http://accesspharmacy.mhmedical.com/content.aspx?bookid=1861&sectionid=132516259. Accessed March 9, 2017.

CONDITION/DISORDER SYNONYMS

• Acne.

DEFINITION

• A common, usually self-limiting disease involving inflammation of sebaceous follicles of face and upper trunk.

ETIOLOGY

• Genetic, racial, hormonal, dietary, and environmental factors.

PATHOPHYSIOLOGY

• Increased sebum production, hyperproliferation of ductal epidermis, bacterial colonization of ducts, and inflammation.

• Androgens cause sebaceous glands to increase size and activity.

• Increased keratinization of epidermal cells and development of obstructed sebaceous follicles (microcomedones)

• The anaerobic bacterium Propionibacterium acnes causes T-cell-mediated inflammation.

• Acne characterized by open and closed comedones is termed noninflammatory acne.

• Inflammatory lesions—including pustules, nodules, and cysts—may form that lead to scarring.

EPIDEMIOLOGY

• Lifetime prevalence is approximately 90%.

• Affects 79–95% of the adolescent population in Western countries.

RISK FACTORS

• Family history of acne.

• Adolescence—30 years of age.

• Elevated testosterone levels.

CLINICAL PRESENTATION

SIGNS AND SYMPTOMS

• Lesions occur on face, back, upper chest, and shoulders.

• Categorized as mild, moderate, or severe, depending on type and severity of lesions.

• Lesions may take months to heal completely; fibrosis may lead to permanent scarring.

DIAGNOSIS

• Established by patient assessment, including observation of lesions and excluding other potential causes (eg, drug-induced acne)

DESIRED OUTCOMES

• Reduce number and severity of lesions.

• Slow disease progression.

• Limit disease duration.

• Prevent formation of new lesions.

• Prevent scarring and hyperpigmentation.

TREATMENT: GENERAL APPROACH

• Select treatments appropriate for severity of clinical presentation.

• Taper effective treatment over time, adjusting to response.

• Use smallest number of agents at lowest effective doses.

• After control is achieved, simplify regimen but continue with some suppressive therapy.

• First line for mild–moderate acne: Exfoliative agents (benzoyl peroxide, topical retinoids, salicylic acid)

• For moderate–severe acne with inflammatory lesions and scars: Reduce P. acnes with benzoyl peroxide, topical antibiotics (alone or with benzoyl peroxide), oral antibiotics (eg, minocycline), retinoids (tretinoin, adapalene, tazarotene), azelaic acid.

• For severe acne with extensive nodules, cysts, and scars, or resistant acne: Add antiandrogens, isotretinoin, or topical and oral antibiotics.

TREATMENT: NONPHARMACOLOGIC THERAPY

• Encourage patients to avoid aggravating factors, maintain balanced diet, and control stress.

• Patients should wash no more than twice daily with mild soap or soapless cleanser. Minimize scrubbing to prevent follicular rupture.

TREATMENT: PHARMACOLOGIC THERAPY

• Topical pharmacotherapy.

  • Exfoliants.

    • Salicylic acid products (up to 2% nonprescription, 5–10% prescription) ...