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INTRODUCTION TO CHAPTER
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Acne and related pilosebaceous disorders rarely cause serious systemic symptoms, but these common skin diseases are often chronic, requiring long term therapy and can cause significant psychosocial distress. These disorders arise from abnormalities associated with the pilosebaceous unit, which is comprised of the hair shaft, hair follicle, and sebaceous gland.
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✓ Acne affects approximately 85% of people between 12 and 24 years of age and can persist into adulthood in up to 50% of affected individuals.
✓ Mild to moderate acne can be managed with topical medications (e.g., topical retinoids, topical benzoyl peroxide and topical clindamycin) and oral antibiotics if needed.
✓ Severe recalcitrant acne that is unresponsive to conventional therapy usually responds to oral isotretinoin.
✓ Patients with acne have higher rates of depression, anxiety, low self-esteem, and suicidal ideation.
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Acne is one of the most prevalent skin disorders, affecting approximately 40–50 million individuals yearly in the United States.1 Although all age groups may be affected by its variants, acne affects approximately 85% of people between 12 and 24 years of age, of which 20–40% have moderate to severe disease.2 Preadolescent acne affecting children 7–11 years of age has become more common with the recent trend for earlier puberty.3 While typically seen in adolescence, acne may persist into adulthood in up to 50% of affected individuals.1
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Acne can have a profound effect on the quality of life,4–6 and affected individuals have higher rates of depression, anxiety, low self-esteem, and suicidal ideation.7 The risk of suicidal ideation and other mental health problems has been shown to be elevated in those with higher self-perceived acne severity.8,9
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The precise role of genetics in the pathogenesis of acne remains an active area of investigation. The number, size, and activity of sebaceous glands are inherited, and studies have demonstrated an association between moderate to severe acne and a family history of acne.10 Genome-wide associated studies (GWAS) have identified genes encoding components of transforming growth factor-β (TGF-β), inflammatory mediators, and regulators of androgen metabolism that may be implicated in those with a genetic predisposition to developing acne.11
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The relationship between diet and acne is gradually being elucidated. Studies have identified skim milk,12 whey protein,13 and a high glycemic-load diet14 as possible risk factors for more severe acne. Vitamin B12 supplementation has been shown to be a possible trigger for acne through alteration of the transcriptome of the skin microflora.15 A recent study demonstrated that consumption of milk, sugary beverages, and fatty and sugary foods are associated with acne in adults.16
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Acne vulgaris is an inflammatory disorder of the pilosebaceous unit. The pathogenesis of acne is ...