Clinical features include: seborrhoea (oily skin), comedones (white and blackheads), inflammatory lesions comprising papules and pustules, as well as nodules. Post-inflammatory hyperpigmentation in addition to scarring may be present4. The scarring may be atrophic as in the case of ice pick scarring or hypertrophic, for example hypertrophic or keloid scarring. Possible differential diagnoses may include rosacea, seborrhoeic dermatitis, medication-induced acne and perioral dermatitis.
Acne may be graded according to signs of disease as well as the impact on quality of life. Global assessment scales may be used1. Moderate to severe acne affects around 20% of young people.3
Acne may be a sign of an underlying endocrine condition, so features such as virilisation, amenorrhoea or oligomenorrhoea, and clitoromegaly should be considered in the history.4 Hirsutism and alopecia as well as acne are skin signs of hyperandrogenism. These features should be considered in an adult female presenting with acne. Topical and oral corticosteroids, anabolic steroids and lithium may cause acne; progestogen-only contraceptives may worsen it.