DermatologyPending review

Acne vulgaris

A disorder of the pilosebaceous unit in which follicular hyperkeratinisation blocks the pore, androgen-driven sebum feeds Cutibacterium acnes, and the resulting inflammation produces comedones, papules, pustules and, in severe disease, scarring.

First principles

Acne starts with a blocked follicle

The first event is hyperkeratinisation of the follicular lining: keratinocytes shed abnormally and stick together instead of flowing out, forming a keratin plug. This plug is the comedone: open to the surface it oxidises and darkens (blackhead); sealed beneath the surface it stays pale (whitehead). Every later stage of acne builds on this initial blockage.

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Educational content pending clinical review. Not medical advice.