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.
Which other follicular disorders is nodulocystic acne (acne conglobata) associated with?
Hidradenitis suppurativa
What is the management of acne fulminans and nodulocystic acne?
Urgent referral to dermatologist
Isotretinoin PO for 5months - start early to prevent scarring
+/- Intralesional steroids post-cyst drainage
In acne fulminans add:
Systemic corticosteroids - 20-60mg prednisolone
NSAIDS - anti-inflammatories like aspirin
Dapsone - sulphonamide
Ciclosporin
High dose erythromycin 2g/day - for secondary infection
TNFa inhibitors e.g. infliximab
Topical preparations usually ineffective
What is the prognosis with nodulocystic acne?
Usuall persists into adult life and will cause scarring unless treated early
What is the management of mild acne vulgaris?
1st line: TOPICAL
2nd line: alternative TOPICAL
1st line topicals:
Benzoyperoxide (BPO)
Antibiotic - erythromycin and clindamycin
Antimicrobial - azelaiz acid, salicylic acid, sodium sulfacetamide
Retinoid
2nd line topicals:
Switch to alternative retinoid/antimicrobial OR
Dapsone - for pustular or papular
What is the management of moderate acne vulgaris?
1st line:
PO Abx + topical retinoid + BPO
2nd line:
Alternative Abx PO + alternative topical retinoid + BPO/azelaic acid OR
Oral isotretinoin
What is the management of severe acne?
1st line:
Oral isotretinoin
2nd line:
PO Abx (high dose) + topical retinoid + BPO OR
PO Dapsone
What is the MOA of retinoids?
Normalises follicular keratinisation and corneocyte cohesion.
Mild anti-inflammatory but helps BPO and other topicals absorb into the follicle
Examples of retinoids: retinoin, adapalene, tazarotene
Which oral antibiotics are usually used in acne?
Tetracyclines (usually) - doxycycline and minocycline
Macrolides (less common) - erythromycin and azithromycin
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 .
What are the side effects of isotretinoin?
On initiation it causes an acne fulminans-like flare with formation of excessive granulation tissue, paronychias and cutaneous infections.
- Cheilitis
- Dryness of oral and nasal mucosa
- Generalised xerosis
- Skin fragility
What must be monitored on isotretinoin?
Serum triglycerides and cholesterol levels - high in 20-50% of patients
NB: patients will sometimes also have raised transaminases, CK.
Is there any link between isotretinoin and depression?
NO causal link established
What would you consider in refractory acne vulgaris?
May be gram negative folliculitis or exogenous cause (e.g. anabolic steroids)
What is the management of acne vulgaris in females with an endocrine cause?
1st line: COCP
2nd line: Spironolactone
Can add maintenance therapy of BPO + topical retinoid.
