Acne Flashcards
What is acne vulgaris
Common chronic disorder of the pilo-sebaceous unit, resulting in blockage of the follicle, formation of comedones and inflammation
What conditions are associated with acne vulgaris
polycystic ovarian syndrome, hyperandrogenism, hypercortisolism, and precocious puberty.
Acne vulgaris pathophysiology
- Increased androgens at puberty; patients may have increased androgen sensitivity of sebaceous glands
- Hypercornification causes keratin plugging of pilosebaceous units
- Infection with corynebacterium acnes (anaerobic bacterium)
- Keratin and sebum build up to produce comedones (whiteheads/blackheads). Sebum production can be caused by increased androgens
- Rupture causes acute inflammation and foreign body granulomas - produces the inflammatory lesions (papules, pustules, cysts and nodules)
What three factors are characteristic of acne vulgaris development
(1) follicular hyperkeratinization
(2) hormonal influences on sebum production & composition
(3) inflammation, in part mediated by cutibacterium acnes
What are microcomedomes
They are the primary lesion of acne & are characterised by small hyperkeratotic plugs composed of corneocytes
Where are microcomedones located in the pilosebaceous units
They are located in the lower region of follicular infundibulum
Whiteheads vs blackheads
Whiteheads
- Closed comedones
- haven’t been oxidised
blackheads
- Open comedones
- have been oxidised
Non inflammatory vs inflammatory lesions in acne vulgaris
- Non-inflammatory (comodones): blackheads & whiteheads
- Inflammatory: papules, pustules, cysts, nodules on erythematous base
What are comodones
Non inflammatory lesions, ‘clogged pores’
Must be present in order to diagnose acne!
Acne vulgaris clinical feature
- Comodones: Blackheads & whiteheads
- Inflammatory lesion: papules, pustules, cysts
- Scarring - atropic, hypertrophic, keloid
- Post-inflammatory hyper/hypopigmentation
- Post-inflammatory erythema
- Psychological dysfunction due to physical appearance
Acne vulgaris location/ distribution
Distribution reflects sebaceous gland sites - face, upper back, anterior chest
Acne vulgaris classification
- Mild: scattered comodones, papules and pustules
- Moderate: numerous papules, pustules & mild atropic scars
- Severe: numerous papules, pustules, severe atrophic scarring, cysts, nodules
Mild-moderate acne treatment
Any 2 of the following in combination for a 12 week course then review:
- Topical benzoyl peroxide
- Topical antibiotics (clindamycin)
- Topical retinoids (tretinoin/adapalene)
Moderate-severe acne treatment
Treated with a 12 week course of the following options:
- Topical retinoid & topical benzoyl peroxide
- Topical retinoid & topical antibiotics
- Topical azelaic acid & oral antibiotic
- Topical retinoid & topical benzoyl peroxide & oral antibiotic
Combined oral contraceptives can be used with topical agents instead of oral antibiotics in women
Severe cystic acne treatment
Systemic antibiotic therapy & isotretinion (roaccutane)
What is acne conglobata
Severe variant of nodulocystic acne
No systemic symptoms
What is acne fulminans
- Acute, painful, ulcerating & haemorrhagic variant of acne vulgaris
- Systemic symptoms - fever, polyarthritis, bone lesions, lab abnormalities
What is acne excoriee
Mild variant of acne vulgaris
Involves comedones that are picked, leading to scarring
Acne vulgaris Histopathology
Dilated follicular opening with cellular debris & bacteria
Leukocytes/ inflammation & fragmented hair shaft
Marked perifollicular inflammation
What topical retinoids are available
Tretinoin & adapelene
What topical antibiotics are first line
Macrolides (clindamycin/erythromycin)
What oral antibiotics are first line & what exemptions exist
Tetracycline (lymecycline/doxycycline)
If <12yrs - erythromycin
If pregnancy/breast feeding - erythromycin or trimethoprim
What is benzoyl peroxide
Keratolytic (anti-comedone) &
Anti microbial &
Anti inflammatory
Benozyl peroxide side effects/ cautions
Can cause erythema & peeling
Can bleaches clothes etc
What is an important side effect of tetracyclines
photosensitivity - must wear sunscreen
What is an important side effect of topical antibiotics
Skin irritation (alcohol based)
Minocycline side effects
Small risk of hepatitis
SLE
Pigmentation
Indications for Isotretinoin (roaccutane)
•Nodulo-cystic acne
•Inadequate response to conventional therapy
•Relapse after adequate antibiotics
•Significant scarring
•Severe psychological impairment (dysmorphophobia)
•post-inflammatory hyperpigmentation
Isotretinoin MOA
Works by reducing sebaceous gland activity
Isotretinoin Side Effects
•Dry skin, lips, eyes (contact lenses) & nose(bleeds)
•Skin fragility
•Hyperlipidaemia
•Abnormal liver function
•Teratogenesis- contraception
•Mood alteration
•Arthralgia
•Acne fulminans
•Hair thinning
What is a side effect of taking both tetracyclines and isotretinoin together
Benign intracranial hypertension
Name the 4 anti-comedonal drugs used in acne vulgaris
Retinoids (Adapalene/ Tretinoin)
Azaleic acid
Benozyl peroxide
Name 3 anti inflammatory drugs used in acne vulgaris
Adapalene
Nicotinamide
Benozyl peroxide
What 3 anti-microbial drugs are used in acne vulgaris
Benzoyl peroxide
Azaleic acid
Antibiotics
What is acne rosacea
Common skin condition characterized by facial flushing that may be triggered by a number of factors e.g. alcohol, stress
Acne rosacea clinical presentation
Recurrent facial flushing:
- Visible blood vessels
- May occur long before onset of rash
- Can be triggered by sunlight, alcohol, stress etc
Rash:
- erythema with papules and pustules
- seen on the nose, chin, cheeks and forehead
- with sparing of naso-labial folds
Acne rosacea triggers
sunlight, alcohol, hot drinks, stress, spicy food
What microorganism is thought to possibly play a role in acne rosacea
Demodex mite
what are the 3 main complications of acne rosacea
•Permanent telangiectasia from repeated flushing
•Ocular inflammation
•Rhinophyma (nasal hyperplasia)
Acne rosacea treatment
• 1st line: Avoid dietary triggers
• Mild: Topical metronidazole or Topical ivermection
• Moderate: Topical invermection & oral tetracycline
• Severe: Roacccutane (Isotretinoin)
Acne rosacea complications treatment
Telangiectasia - laser therapy
Rhinophyma - surgery
How is the rash is acne vulgaris different to acne rosacea
In acne rosacea
- no comedones
- normal sebum excretion rate
