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INTRODUCTION TO CHAPTER
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Acne and related pilosebaceous disorders rarely cause serious systemic problems, but they are among the diseases that can cause significant psychosocial distress. Most of these disorders are chronic and require long-term therapy with topical and if needed, oral antibiotics. However, there are increasing concerns about the development of bacterial resistance to antibiotics, especially in patients with acne and rosacea who may take antibiotics for several years.1
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The prevalence of acne in adolescents has been reported to be as high as 95% with a 20% to 35% prevalence of moderate to severe acne.2 Acne may persist into adulthood in up to 50% of affected individuals.3 Transient acne may occur in newborns and occasionally acne will begin in adulthood.
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Quality of life issues are a very important concern for individuals (especially teenagers) with acne. Depression, anxiety, and low self-esteem are more common in patients with acne.4 Interestingly, there is no correlation between acne severity and degree of the mental health symptoms. Most clinicians who regularly treat acne (and parents of teenagers) are aware of the negative emotional impact of even a few "pimples."
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The pathogenesis of acne is complex, but there are several major factors that contribute to the development of an acne lesion.2,3
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Hyperproliferation and adhesion of keratinocytes in the distal portion of the hair follicle creates a keratin plug (microcomedone).
Androgenic hormones stimulate increased sebum production.
Propionibacterium acnes (P. acnes), an anaerobic, lipophilic, resident bacteria, proliferates in the sebum-rich environment of the plugged hair follicle.
P. acnes and other factors trigger the release of inflammatory mediators that diffuse through the wall of the follicle into the surrounding dermis resulting in an inflammatory papule or pustule.
The follicular wall ruptures and bacteria, sebum, and other follicular components are released into the dermis creating an inflamed nodule.
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Several other factors such as genetics and emotional stress and affect the development and severity of acne.
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Clinical Presentation
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Acne usually presents at the onset of puberty with comedones on the central face. Inflammatory papules and/or pustules may develop in early to mid-teen years and are usually confined to the face, but the neck and back may be affected. Patients with nodular acne may complain of pain and tenderness. Acne is typically a chronic disorder that does not begin to resolve until the late teens.
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Acne typically presents with 4 types of lesions, comedones, inflammatory papules, pustules, and nodules. In the past the term "cystic acne" was used, but acne does not have true cysts with an epithelial lining. However, large fluctuant nodules do have a cystic appearance. ...