Acneforms eruptions

Question 1

Describe how acne vulgaris develops

Answer 1

• “Sticky” keratinocytes + increased sebum viscosity – causes them to aggregate and form a plug over follicles, leading to keratinocytes blocked in and cannot be shed when they die
• Blocked follicles = comedones.
• These can be blackheads (open) or whiteheads (closed)
• Change in commensal bacterial behaviour (Propionobacterium acnes) = inflammation

Question 2

Describe the epidemiology of acne vulgaris

Answer 2

• Peak 15-18 years (90% incidence)
• Delayed onset in some females
• +ve family history
• M=F – but M more severe
• Psychological impact is huge

Question 3

List the topical treatments available for acne vulgaris

Answer 3

o Retinoids – make keratinocytes “less sticky”, in am
o Benzoyl peroxide (BPO) – antibacterial, in pm
o Antibiotics: clindamycin, tetracycline, erythromycin
o Others

Question 4

List the non-topical treatments available for acne vulgaris

Answer 4

o Antibiotics: tetracyclines or erythromycin (trimethoprim) in pregnant woman (T makes childrens teeth grey)
o Anti-androgens: combined oral contraceptives (Dianette)
o isotretinoin/Roaccutane – best for severe acne
o (Light based treatments)

Question 5

What drug causes grey teeth in babies if taken while pregnant?

Answer 5

Trimethoprim

Question 6

What is the best treatment available for severe acne vulgaris?

Answer 6

isotretinoin/Roaccutane

Question 7

What is the recommended dose of isotretinoin/Roaccutane?

Answer 7

1mg/kg/day for 16 weeks – recommend dose to be half of this (to avoid dry skin caused by treatment)

Question 8

What are the disadvantages of isotretinoin/Roaccutane?

Answer 8

o	Highly teratogenic (pregnancy prevention programme) – teratogenic effects last for 1 month post treatment, must have negative pregnancy test before starting treatment
o	Many (potential) side-effects
o	Very dry skin (especially at muco-cutaneous junctions)
o	Hair loss
o	Mood swings/depression/suicide
o	Abnormal LFT’s
o	Hypertriglyceridaemia
o	Expensive

Question 9

What is acne rosacea?

Answer 9

Chronic inflammation of:
• PSU (pilo-sebaceous unit)
• Cutaneous vasculature

Question 10

Describe the distribution of acne rosacea

Answer 10

• Ace of clubs distribution – over cheeks, nose and middle of forehead
• Unusual on non-facial sites

Question 11

Describe the epidemiology of acne rosacea

Answer 11

• Age 30-50 years
• F > M – but M more severe
• Fair skinned/Celts are of higher risk
• Some can experience significant flushing – often in response to alcohol, spices, emotion, hot drinks etc
• “Sensitive” skin – common complaint e.g. irritation by conventional skin products

Question 12

What are the subtypes of acne rosacea?

Answer 12

• Erythemato-telangiectatic – lots of erythema and spider veins
• Papulo-pustular – many papules and pustules
• Phymatous (M»>F) – hyperplastic enlargement of sebaceous glands, particularly on the nose
• Ocular – affects the eye, causes dry gritty eyes, can cause keratitis and affect vision

Question 13

How can you tell between acne vulgaris and acne rosacea?

Answer 13

Distribution
Age
Presence of comedones

Question 14

What topical treatments are available for acne rosacea?

Answer 14

o Antibiotics – metronidazole
o Azeleic acid - can cause irritation
o Ivermectin – also used for scabies
o Brimonidine – topical vasoconstrictor, good for Erythemato-telangiectatic rosacea, reduces redness for 8hrs (special circumstances)

Question 15

What is a good treatment for Erythemato-telangiectatic rosacea?

Answer 15

Brimonidine

Light based treatments

Question 16

What is Brimonidine?

Answer 16

Brimonidine – topical vasoconstrictor, good for Erythemato-telangiectatic rosacea, reduces redness for 8hrs (special circumstances)

Question 17

Describe some non-topical treatments of acne rosacea

Answer 17

o Antibiotics – tetracyclines, (if not suitable use erythromycin), (or metronidazole)

o Isotretinoin – for severe cases, use lower doses again (0.25-0.5mg/kg), not curative in acne rosacea

o Light based treatments – best treatment for erythemato-telangiectatic rosacea

Question 18

What dose of isotretinoin used for acne rosacea?

Answer 18

0.25-0.5mg/kg/day for 16 weeks

Question 19

What drug can be given to those with erythemato-telangiectatic rosacea for temporary suppression of redness e.g. for special circumstances?

Answer 19

Brimonidine