Acne vulgaris Flashcards
Define acne vulgaris.
The common form of acne, characterised by a mixed eruption of inflammatory and non-inflammatory skin lesions (see all the acne types).
How common is acne? Who is most affected?
Very common
All ethnic groups
Peak age 11-15 in girls, 15-17 in boys - 90% of adolescents affected
What are risk factors for acne?
- XXY karyotype
- Endocrine disorders
- PCOS
- Hyperandrogenism
- Hypercortisolism
- Precocious puberty
- FH - number size and activity of sebaceous glands is inherited
- Diet - skimmed milk increases risk
- Protein supplements
- Stress
- Drugs - steroids, hormones, anticonvulsants
What are some causes of occupational acne/ acne cosmetica/pomade acne?
Cutting oild
Petroleum-based products
Chlorinated aromatic hydrocarbons
Coal tar derivatives
Cosmetics and hair products which occlude follicles
What is the cause of chloracne?
Exposure to halogenated aromatic hydrocarbons - often recalcitrant to therapy
What is the cause of tropical acne?
Exposure to extreme heat
What is the cause of radiation acne?
Post-radiation dermatitis
Where does acne usually occur on the body?
Depends on activity of the sebaceous glands in particular areas of the body
Commonest sites are shoulders, back, chest, arms, neck, buttocks and legs.
What are the types of acne lesions?
Inflammatory:
- Papules
- Pustules
- Nodules
- Cysts
Non-inflammatory:
- Open comedones or blackheads
- Closed comedones or whiteheads
What types of lesions are these?
Open comedones, closed comedones, giant comedone
What type of inflammatory acne is this?
Nodulocystic - usually gram +ve bacilli cause this
What is the pathogenesis of acne?
- Follicular hyperkeratinisation
- Hormonal influences on sebum production and composition
- Inflammation, in part mediated by Proprionibacterium acnes
What are the grades of acne?
< 20 comedones, < 15 inflammatory lesions, or total < 30 = MILD
< 100 comedones, < 50 inflammatory lesions, or total < 125 = MODERATE
> 5 pseudocysts, > 100 comedones, > 50 inflammatory lesions, or total > 125 = SEVERE
Define acne fulminans.
Most severe form of acne characterised by the abrupt development of nodular and suppurative acne lesions in association with systemic manifestations.
There may be bleeding crusts over the ulcers on the upper trunk. Severe acne scarring occurs.
What are some systemic manifestations of acne fulminans?
Osteolytic bone lesions
Fever
Arthralgias
Myalgias
Hepatosplenomegaly
Severe malaise
Erythema nodosum
Bloods will show anaemia, raised WCC, raised ESR and CRP, XRays with osteolytic bone lesions.
Define acne conglobata.
Severe form of nodulocystic acne that may have an eruptive onset but without systemic manifestations.
Lesions are firm, fluctuant +/- tender and usually involve the face, neck and trunk. Hyperpigmentation and keloid scarring are common.
What are the effects of retinoids/isotretinoin on the whole body?
Retinoids are structural and functional analogues of Vitamin A that exert many effects on cellular differentiation and proliferation, the immune system and embryonic development .
