Acne Vulgaris

Question 1

What is the pathophysiology of acne vulgaris?

Answer 1

• Follicular epidermal hyperproliferation resulting in the formation of a keratin plug. This in turn causes obstruction of the pilosebaceous follicle.
• Activity of sebaceous glands may be controlled by androgen, although levels are often normal in patients with acne
• colonisation by the anaerobic bacterium Propionibacterium acnes
• inflammation

Question 2

What is the difference between mild, moderate and severe acne?

Answer 2

• Mild: open and closed comedones with or without sparse inflammatory lesions
• Moderate acne: widespread non-inflammatory lesions and numerous papules and pustules
• Severe acne: extensive inflammatory lesions, which may include nodules, pitting, and scarring

Question 3

Describe the simple step management scheme of treating acne vulgaris.

Answer 3

1. Single topical therapy (topical retinoids, benzyl peroxide)
2. Topical combination therapy (topical antibiotic, benzoyl peroxide, topical retinoid)
3. Topical azelaic acid - second line.
4. Oral antibiotics: e.g. Oxytetracycline, doxycycline. Improvement may not be seen for 3-4 months.
   
   • Minocycline is now considered less appropriate.
   • Gram negative folliculitis may occur as a complication of long-term antibiotic use - high-dose oral trimethoprim is effective if this occurs
5. Oral isotretinoin: only under specialist supervision

Question 4

Why is minocycline less appropriate for treating acne now?

Answer 4

It can cause hyperpigementation and drug induced lupus.

Question 5

What is a side effect to be aware of when treating with trimethoprim?

Answer 5

Thrombocytopenia.

Question 6

How old must children be to use tetracycline?

Answer 6

12 years old

Question 7

Who should make the decision about long term trimethoprim use?

Answer 7

Specialists.

Question 8

Describe the characteristic skin features of acne vulgaris.

Answer 8

Obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules.

Question 9

What percentage of teenagers are affefcted by acne vulgaris and what % of those seek help?

Answer 9

80-90% of teenagers

60% of whom seek help

Question 10

Who is more likely to get acne after adolescence & beoynd the age of 25, males or females?

Answer 10

Females 10-15%

Males 5%

Question 11

What are the referral criteria for acne?

Answer 11

Refer all with severe acne in order to alleviate pain and psychological distress and to limit scarring.

Question 12

How should you treat mild acne?

Answer 12

• First line - topical retinoid or benzoyl peroxide.
• Second line - azelaic acid.
• Consider COCP for women.
• Follow up in 6-8 weeks - if treatment fails continue with the next step.
• Third line - topical antibiotics + retinoids +/- benzoyl peroxide.
  
  • clindamycin OD, erythromycin BD.
  • Continue for 12 weeks and then stop & review.

Question 13

How should you treat moderate acne?

Answer 13

• Consider the following
  
  • Topical retinoid (avoid in pregnancy) or benzoyl peroxide.
  • Topical azelaic acid.
  • Topical antibiotics + benzoyl peroxide +/- topical retinoid.
  • Oral antibiotics +/- topical retinoids or benzoyl peroxide.
    
    • First line - Doxycyline, Oxytetracycline
    • Second line - Erythromycin is an alternative - e.g. pregnancy.
  • Consider COCP for women.
• Follow up in 6-8 weeks
  
  • If treatment helping then continue for 6 months.
  • If no response after 2 to 3 months then consider changing antibiotics or referral.

Question 14

How should you treat severe acne?

Answer 14

• Refer
• Whilst waiting for referral consider:
  
  • Oral antibiotics + topical retinoids or benzoyl peroxide.
  • COCP

Question 15

How can you treat acne in pregnancy?

Answer 15

Use either benzoyl peroxide or oral erythromycin if treatment needed