- Clinical science
Acne vulgaris is a common skin disease that affects most individuals at some point in their lives. It is classified into different forms which vary in severity, lesion type, and localization, with the face commonly involved. The hallmark of acne are comedones, which can develop further into inflammatory papules, pustules, or even abscesses and nodules. Symptoms typically begin in early puberty and cease spontaneously during the third decade of life. The are multiple etiological factors: genetic predisposition, seborrhea, and hyperkeratosis are known to promote the development of acne. Topical and systemic treatment options are available to counteract inflammation and hyperkeratosis, as well as to help purify the skin.
- Prevalence: 85% of the population is affected (!)
- Age of onset: typically by 11–12 years, with symptoms usually disappearing around 20–30 years of age
- Sex: more common in males during adolescence, but more common in women during adulthood
Epidemiological data refers to the US, unless otherwise specified.
- Localization: common in areas with sebaceous glands (predilection sites: face, shoulders, upper chest, and back)
Non-inflammatory: comedonal acne
- Closed comedones (“whiteheads”): closed small round lesions that contain whitish material (sebum and shed keratin)
- Open comedones (“blackheads”): dark, open portion of sebaceous material
- Inflammatory: affected areas are red and can be painful
- Non-inflammatory: comedonal acne
- Secondary lesions: postinflammatory erythema, hyperpigmentation, and scarring
Hidradenitis suppurativa (also acne inversa): inflammation of the hair follicles, most likely triggered by a blockage
- Risk factors: obesity, smoking, family history
- Localization: in folded skin areas (most commonly the axillae, groin, inner thigh, and perineal area)
- Formation of abscesses, fistulas, and keloids
- Formation of draining sinuses with scarring and foul odor
- Age of onset: first few weeks of life
- Clinical presentation: papulopustular rash
- Treatment: self-limiting disease ; no specific treatment
- Age of onset: ≥ 3 months
- Clinical presentation: papulopustular rash, closed comedones, and sometimes formation of nodules. More common in boys.
- Treatment: In contrast to neonatal acne, treatment is indicated to avoid scarring
|Mild (e.g., comedonal)||Moderate (e.g., papular/pustular)||Severe (e.g., conglobata)|
- Therapy is particularly important for patients with inflammatory acne to prevent complications such as scarring.
Main substance: isotretinoin (Vitamin A derivative) given systemically
- Indication: in moderate to severe acne
- Mechanism of action: Retinoids normalize keratinization by inhibiting and modulating keratinocytes → ↓ sebum production
Precautions (in all females of childbearing potential)
- 1 month before initiating therapy:
- During therapy: monthly pregnancy test and continuous use of two methods of contraception
- After completing therapy:
- Continue two methods of contraception for 1 month
- A pregnancy test at the end of 1 month
- Side effects
Retinoid therapy should be discontinued at latest one month before planned conception!