Acne

Question 1

What 3 physiological processes involved in acne?

Answer 1

1. INCREASE in sebum excretion rate (SER)
2. HYPERCORNIFICATON of the follicular lining leading to obstruction of the pilosebaceous ducts
3. COLONISATION with bacterium propionibacterium acnes within the pilosebaceous ducts and subsequent inflammation

Question 2

What hormones promote sebum production and secretion?

Answer 2

Androgens (e.g. dihydrotestosterone)

Question 3

What is seborrhoea?

Answer 3

Greasy skin due to increased sebum secretion

Question 4

Are androgen levels higher in pts with acne?

Answer 4

not usually, it is thought to be receptor hypersensitivity rather than excess hormone in the blood

Question 5

What occurs in the hypercornification stage of acne?

Answer 5

Occurs at the same time as seborrhoea -

the keratinocyte cells lining these ducts show abnormal differentiation

so that there is hyperkeratosis,

and abnormal shedding.

This leads to retention of the cell lining

and resultant occlusion of the ducts,

forming a microcomedo in affected ducts

Question 6

What is a microcomedo?

Answer 6

a blocked pore which is the

PRIMARY lesion of acne

Question 7

In what type of duct does ance occur in?

Answer 7

pilosebaceous duct

Question 8

What bacteria causes inflammation in acne?

Answer 8

propionibacterium acnes

Question 9

How does propionibacterium acnes cause inflammation?

Answer 9

Chemotactic and pro-inflammatory mediators diffuse into the surrounding dermis`

Question 10

What are the two categories of lesions found in acne?

Answer 10

Non-inflammatory lesions

Inflammatory lesions

Question 11

What are the non-inflammatory lesions found in acne?

Answer 11

Open comedones (blackheads)

Closed comedomes (whiteheads)

Question 12

Which category of comedomes are more likely to become inflamed and why?

Answer 12

Closed comedones as they are more likely to rupture

Question 13

What are the inflammatory lesions found in acne?

Answer 13

erythematous papules

pustules

nodules

cysts (rarely)

abscesses (rarely)

Question 14

Which form of acne do abscesses almost uniquely form in? (starts in adulthood)

Answer 14

acne conglobate (starts in adulthood)

Question 15

What must all acne conditions begin with?

Answer 15

microcomedo

Question 16

Name some commoner types of acne?

Answer 16

Acne vulgaris (most common)

Acne cosmetica

Acne medicamentosa (esp. steroids)

Question 17

What is the advice regarding closed comedones?

Answer 17

Do not pop as will further inflame lesion

Question 18

Which medications can worse acne?

Answer 18

high progesterone-containing OCP

potent topical or oral steroids

Question 19

What are the DDx’s for acne? (how can the be differentiated)

Answer 19

rosacea

peri-oral dermatitis

folliculitis

(but there are no comedones in any of these conditions)

Question 20

What should you investigate in children with acne?

Answer 20

full endocrine evaluation

to exclude an

androgen-secreting tumour of the

adrenals or

ovaries

Question 21

What are the treatments in acne vulgaris?

Answer 21

Antibacterials - topical

Antiobiotics - oral or topical

Retinoids - oral or topical

Hormone therapy

Question 22

For how long should acne treatments last (except for what)?

Answer 22

6 weeks (except systemic retinoids e.g. isotretinoin)

Question 23

What are the two types of topical antibacterial use in acne? (which is more commonly used)

Answer 23

benzoyl peroxide (widely used)

azelaic acid cream (rarely used)

Question 24

How often should antibacterials be applied in acne? (however what is the problem with this)

Answer 24

twice a day (often not possible as causes irritation)

Question 25

How do topical antibacterials in acne reduce inflammation?

Answer 25

They have some comedolytic activity, but its main effects is reducing the number of p.acnes bacteria and inflammation

Question 26

What are the benefits of antibacterials?

Answer 26

No problems with resistance

Question 27

What are the negatives of antibacterials?

Answer 27

Cause local irritation BPO can bleach clothes

Question 28

How do topical retinoids work?

Answer 28

They are comedolytic, which means they remove the surface keratin - essentially unblocking the pores and allowing drainage of microcomedonal contents

Question 29

What are first line therapy for comedonal acne?

Answer 29

Topical retinoids

Question 30

What are the risks of topical retinoids?

Answer 30

Still teratogenic even in the topical form and should not be used in breast-feeding or pregnancy

Question 31

Which antibiotics are used topically?

Answer 31

Erythromycin and clindamycin

Question 32

What is a particular problem with topical antibiotics and how is the avoided?

Answer 32

Resistance, thus it is combined with BPO and limited to 6 months

Question 33

For what type of acne is BPO particularly useful?

Answer 33

Papulopustular acne

Question 34

What are the indications for systemic treatment over topical treatment for acne?

Answer 34

Moderate to severe acne Failure of topical treatment Scarring (or marked post-inflammatory hyperpigmentation) Consider if chest or back involvement

Question 35

How should a pt transition from topical to oral treatment for acne?

Answer 35

A pt should use topical treatment for acne aswell as systemic at least 1 topical treatment should be used

Question 36

What are the 1st and 2nd line systemic antibiotic treatments for acne?

Answer 36

1) Lymecycline (most common) 1) Doxycycline 1) Tetracycline 2) macrolides -> Erythromycin

Question 37

In whom are cyclines contraindicated? (Why)

Answer 37

pregnancy (tetragenic) breastfeeding (tetragenic) children (stains teeth)

Question 38

What are the benefits and problems with erythromycin?

Answer 38

Benefit - safe in pregnancy Issue - GI side effects Issue - staph resistance

Question 39

For how long should systemic antibiotics be used?

Answer 39

at least 6 weeks if there is no clinical effect, use an alternative antibiotic

Question 40

If you are using topical and systemic antibiotics should you use the same or different antibiotics?

Answer 40

Use the same antibiotics, so bacteria only become resistant to one type of antibiotics

Question 41

What require monitoring when a pt is on isotretinoin?

Answer 41

FBC LFTs Fasting lipids Pregnancy test

Question 42

What are the side effects of systemic retinoids?

Answer 42

photosensitivity teterogenic (contraindicated in breast-feeding and pregnancy) Depression Hyperlipidaemia Deranged liver function

Question 43

What % of pts who take systemic retinoids will relapse?

Answer 43

About 25%

Question 44

Who must prescribe systemic retinoids and why?

Answer 44

A dermatologist due to serious side effects

Question 45

What hormone therapy is used in acne?

Answer 45

cyproterone acetate | known as “Dianette” in the UK

Question 46

What are the problems with cyproterone acetate ?

Answer 46

variable tolerance increased risk of venous thromboembolism

Question 47

Minor acne has what characteristics?

Answer 47

+ papules and pustules

Question 48

Moderate acne has what characteristics?

Answer 48

+/++ papules and pustules -/a few small nodules/cysts + inflammation

Question 49

Severe acne has what characteristics?

Answer 49

+++ papules and pustules mainly small nodules/cysts ++ inflammation + scaring

Question 50

Very severe acne has what characteristics?

Answer 50

+++ papules and pustules +++ nodules/cysts +++ inflammation + scaring

Question 51

What is the indication that acne will scar?

Answer 51

Greater inflammation = more scarring

Question 52

What are possible treatments for acne scarring?

Answer 52

Dermabrasion Microdermabrasion Excision Laser resurfacing Intralesional steroid for keloid scars

Question 53

At what stage of acne should scars be treated?

Answer 53

Once acne is no longer active

Question 54

What are the possible sequelae in acne vulgaris?

Answer 54

Resolution (i.e. no scaring) or scaring

Question 55

What are the types of scars that occur in acne vulgaris?

Answer 55

Ice pick scar Atrophic scar Keloid/hypertrophic scar

Question 56

If you have to retreat acne should you change antibiotic?

Answer 56

No assuming it was effective last time, use the same antibiotic

Question 57

How long should systemic retinoids (isotretinoin) be used for?

Answer 57

4-6mnths