A 22-year-old woman comes to the office due to several years of persistent facial blemishing that has failed to respond to over-the-counter treatment. The patient has no other medical conditions. She does not use tobacco, alcohol, or illicit drugs. Skin examination findings are shown in the image below:
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Which of the following most likely contributed to the pathogenesis of this patient's skin condition?
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This patient's red papules and pustules on the face are consistent with inflammatory acne. The pathogenesis of acne involves the following:
Hyperkeratinization due to abnormal epithelial growth and differentiation of corneocytes leads to keratin plug formation in the pilosebaceous follicles. These blocked follicles are referred to as comedones (ie, whiteheads and blackheads).
In response to androgen stimulation (eg, during pubertal adrenarche), sebaceous glands enlarge (not involute) and increase production of sebum, a lipid-rich substance that facilitates obstruction of pilosebaceous follicles (Choice A).
Cutibacterium acnes, an anaerobic bacteria that relies on sebum as a nutrient source, proliferates in occluded follicles, triggering an inflammatory response that results in the red papules and pustules characteristic of nodulocystic acne.
(Choice B) Bacterial metabolism of apocrine secretions contributes to body odor. Bromhidrosis is a condition characterized by excessive and offensive body odor.
(Choice C) Estrogen has antiandrogenic effects and inhibits sebum production. For this reason, estrogen-containing oral contraceptives help to improve inflammatory acne.
(Choice D) As epithelial stem cells undergo mitosis in the basal layers of the epidermis, newer cells form and undergo differentiation as they migrate toward the surface, replacing epithelial cells that desquamate. Increased epithelial mitosis and desquamation (ie, topical retinoids) helps extrude debris from comedones, limiting acne formation.
Educational objective:
Acne is characterized by the obstruction of pilosebaceous follicles (ie, comedones) due to hyperkeratinization and excessive sebum accumulation. Androgens stimulate production of sebum, which serves as a nutrient source for Cutibacterium acnes. Within the follicles, C acnes proliferation triggers an inflammatory response, resulting in formation of red papules and pustules.