ACNE VULGARIS
Acne vulgaris = dermatological condition caused by inflammation of the pilosebaceous unit.
Macules = flat marks on skin.
Papules = small lumps on skin.
Pustules = small lumps containing yellow pus.
Comedomes = skin coloured papules respresenting blocked pilosebaceous units.
Blackheads = open comedones with black pigmentation.
Ice pick scars = small indentations in the skin that remain after acne lesions heal.
Hypertrophic scars = small lumps in the skin that remain after acne lesions heal.
Rolling scars = irregular wave-like irregularities of the skin that remain after acne lesions hea.
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Presentation
Characterised by inflammatory and non-inflammatory lesions that affect the face, chest and back.
Non-inflammatory comedones
§ Closed comedones aka whiteheads ® plugged follicles
§ Open comedones aka blackheads ® follicles with dilated openings
Inflammatory papules, pustules, nodules and cysts
§ Papules, pustules ® superficial, small, raised lesions <5mm
§ Nodules, cysts ® deep, large, raised lesions >5mm.
In chronic disease, you may also see hyperpigmentation, inflammatory depigmentation or scarring.
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Pathophysiology
Inflammation of the pilosebaceous unit.
§ Acne is caused by chronic inflammation +/- localised infection in the pilosebaceous unit
o Pilosebaceous unit = small dimples in skin containing hair follicles and sebaceous glands
o Sebaceous glands produce natural skin oils and sebum
§ Acne results from four key factors/processes:
o Increased sebum production
o Trapping of keratin
o Blockage of pilosebaceous unit
o Bacteria ® cutibacterium acnes/Propionibacterium acnes
§ These 3 processes cause ® swelling and inflammation
§ Swollen and inflamed units = comedones
§ Androgenic hormones ® increase sebum production
o Exacerbated by puberty, alleviated by anti-androgenic hormonal contraception
§ Propionibacterium acnes bacteria colonises the skin ® excessive growth exacerbates acne
§ The condition is characterised by:
o Non-inflammatory comedones
o Inflammatory papules, pustules and nodules
§ These lesions are thought to arise from precursor lesions ® microcomedo
Severity Grading
There isn’t a single universal classification for severity.
Mild-moderate acne includes 1 or more of:
1. Any number of non-inflammatory lesions (comedones)
2. Up to 34 inflammatory lesions
3. Up to 2 nodules.
Moderate-severe acne includes either or both of:
1. 35 or more inflammatory lesions
2. 3 or more nodules.
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Investigation
This is a clinical diagnosis.
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Acne vulgaris = dermatological condition caused by inflammation of the pilosebaceous unit.
Macules = flat marks on skin.
Papules = small lumps on skin.
Pustules = small lumps containing yellow pus.
Comedomes = skin coloured papules respresenting blocked pilosebaceous units.
Blackheads = open comedones with black pigmentation.
Ice pick scars = small indentations in the skin that remain after acne lesions heal.
Hypertrophic scars = small lumps in the skin that remain after acne lesions heal.
Rolling scars = irregular wave-like irregularities of the skin that remain after acne lesions hea.
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Presentation
Characterised by inflammatory and non-inflammatory lesions that affect the face, chest and back.
Non-inflammatory comedones
§ Closed comedones aka whiteheads ® plugged follicles
§ Open comedones aka blackheads ® follicles with dilated openings
Inflammatory papules, pustules, nodules and cysts
§ Papules, pustules ® superficial, small, raised lesions <5mm
§ Nodules, cysts ® deep, large, raised lesions >5mm.
In chronic disease, you may also see hyperpigmentation, inflammatory depigmentation or scarring.
-----------------------------------------------------------------------------------------------------------------------------------------------------
Pathophysiology
Inflammation of the pilosebaceous unit.
§ Acne is caused by chronic inflammation +/- localised infection in the pilosebaceous unit
o Pilosebaceous unit = small dimples in skin containing hair follicles and sebaceous glands
o Sebaceous glands produce natural skin oils and sebum
§ Acne results from four key factors/processes:
o Increased sebum production
o Trapping of keratin
o Blockage of pilosebaceous unit
o Bacteria ® cutibacterium acnes/Propionibacterium acnes
§ These 3 processes cause ® swelling and inflammation
§ Swollen and inflamed units = comedones
§ Androgenic hormones ® increase sebum production
o Exacerbated by puberty, alleviated by anti-androgenic hormonal contraception
§ Propionibacterium acnes bacteria colonises the skin ® excessive growth exacerbates acne
§ The condition is characterised by:
o Non-inflammatory comedones
o Inflammatory papules, pustules and nodules
§ These lesions are thought to arise from precursor lesions ® microcomedo
Severity Grading
There isn’t a single universal classification for severity.
Mild-moderate acne includes 1 or more of:
1. Any number of non-inflammatory lesions (comedones)
2. Up to 34 inflammatory lesions
3. Up to 2 nodules.
Moderate-severe acne includes either or both of:
1. 35 or more inflammatory lesions
2. 3 or more nodules.
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Investigation
This is a clinical diagnosis.
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