DERM: Acne Flashcards
Describe the pathogenesis of acne
- Acne results from increased production of sebum, trapping of keratin (dead skin cells) and blockage of the pilosebaceous unit.
- leads to swelling and inflammation in the pilosebaceous unit.
what is the pilosebaceous unit and what is its contents?
The pilosebaceous units are the tiny dimples in the skin that contain the hair follicles and sebaceous glands.
why is acne exacerbated by puberty and improved with anti-androgenic hormonal contraception?
Androgenic hormones increase the production of sebum
what is a comedo/comedones?
SPOTS
- A single lesion is a comedo.
- Open comedones are blackheads; black because of surface pigment (melanin), rather than dirt. Closed comedones are whiteheads; the follicle is completely blocked.
which bacteria is thought to exacerbate acne?
The Propionibacterium acnes bacteria is felt to play an important role in acne. This is a bacteria that colonises the skin.
what is acne?
Acne is caused by chronic inflammation, with or without localised infection, in pockets within the skin known as the pilosebaceous unit.
who does acne commonly affect?
often affecting people during puberty and adolescence
what is Seborrhoea with reference to acne?
excessive discharge of sebum from the sebaceous glands.
what are Macules with reference to acne?
Macules are flat marks on the skin
what are Papules with reference to acne?
Papules are small lumps on the skin
what are Pustules with reference to acne?
Pustules are small lumps containing yellow pus
what are Ice pick scars with reference to acne?
Ice pick scars are small indentations in the skin that remain after acne lesions heal
what are Hypertrophic scars with reference to acne?
Hypertrophic scars are small lumps in the skin that remain after acne lesions heal
what are rolling scars with reference to acne?
Rolling scars are irregular wave-like irregularities of the skin that remain after acne lesions heal
What is the first line topical treatment for acne?
Topical benzoyl peroxide
- reduces inflammation, helps unblock the skin and is toxic to the P. acnes bacteria
with reference to acne, if Topical benzoyl peroxide doesn’t work what are alternative treatments?
- Topical retinoids
- Topical antibiotics
- Oral antibiotics
- Oral contraceptive pill
how do topical retinoids act on acne?
(chemicals related to vitamin A) slow the production of sebum
how do antibiotics act on acne?
prescribed with benzoyl peroxide to reduce bacterial resistance
how does the oral contraceptive pill act on acne?
Oral contraceptive pill can help female patients stabilise their hormones and slow the production of sebum
should females use oral retinoids for acne during pregnancy?
It is strongly teratogenic (harmful to the fetus during pregnancy). Patients need to have effective and reliable contraception and must stop isotretinoin for at least a month before becoming pregnant.
name a common type of oral retinoid used in severe acne?
Oral isotretinoin (Roaccutane)
what are the side effects of Oral isotretinoin (Roaccutane)?
- Dry skin and lips
- Photosensitivity of the skin to sunlight
- Depression, anxiety, aggression and suicidal ideation. Patients should be screened for mental health issues prior to starting treatment.
- Rarely Stevens-Johnson syndrome and toxic epidermal necrolysis
