ACNE

Question 1

pathophysiology of acne

Answer 1

obstruction of the pilosebaceous follicles with keratin plugs which results in comedones, inflammation and pustules.

Question 2

classification of 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

management for acne

Answer 3

1) single topical therapy - (topical retinoids, benzoyl peroxide)
salicylic acid- mild acne

2) topical combination therapy (topical antibiotic, benzoyl peroxide, topical retinoid)
3) oral ABx - moderate to severe
4) COCP
5) oral isotretinoin - severe acne

Question 4

what type of ABx we use acne

Answer 4

• tetracyclines: lymecycline, oxytetracycline, doxycycline 50-200mg daily for 6 months
• tetracyclines should be avoided in pregnant or breastfeeding women and in children younger than 12 years of age
• erythromycin may be used in pregnancy
• minocycline is now considered less appropriate due to the possibility of irreversible pigmentation
• a single oral antibiotic for acne vulgaris should be used for a maximum of three months
• a topical retinoid (if not contraindicated) or benzoyl peroxide should always be co-prescribed with oral antibiotics to reduce the risk of antibiotic resistance developing. Topical and oral antibiotics should not be used in combination
• Gram-negative folliculitis may occur as a complication of long-term antibiotic use - high-dose oral trimethoprim is effective if this occurs

Question 5

COCP options for acne

Answer 5

• as with antibiotics, they should be used in combination with topical agents
• Dianette (co-cyrindiol) is sometimes used as it has anti-androgen properties. However, it has an increased risk of venous thromboembolism compared to other COCPs, therefore it should generally be used second-line, only be given for 3 months and women should be appropriately counselled about the risks

Question 6

what is contradicted in oral isotretinoin

Answer 6

pregnancy

Question 7

causes of acne

Answer 7

• Hormonal (androgen)

Contributing factors include:
- increased sebum production
- abnormal follicular keratinization
- bacterial colonization
 (Propionibacterium acnes) and inflammation

Flares of acne can be provoked by:

Polycystic ovarian disease
Drugs: steroids, hormones, anticonvulsants, epidermal growth factor receptor inhibitors and others
Application of occlusive cosmetics
High environmental humidity
Diet high in dairy products and high glycaemic foods.

Question 8

complications of acne

Answer 8

Post-inflammatory hyperpigmentation
scarring
deformity
psychological and social effects

Question 9

features of acne rosacea

Answer 9

• typically affects nose, cheeks and forehead
• flushing is often first symptom
• was telangiectasia are common
• later develops into persistent erythema with papules and pustules
• rhinophyma
• ocular involvement: blepharitis
  sunlight may exacerbate symptoms/

Question 10

what else does acne rosacea effect

Answer 10

blepharitis, keratitis, conjunctivitis

Question 11

management for acne rosacea

Answer 11

• topical metronidazole may be used for mild symptoms (i.e. Limited number of papules and pustules, no plaques)
• topical brimonidine gel may be considered for patients with predominant flushing but limited telangiectasia
• more severe disease is treated with systemic antibiotics e.g. Oxytetracycline
• recommend daily application of a high-factor sunscreen
• camouflage creams may help conceal redness
• laser therapy may be appropriate for patients with prominent telangiectasia
• patients with a rhinophyma should be referred to dermatology

Question 12

adverse effects of isotretinoin

Answer 12

most common side effect -> dry skin

• teratogenicity: females should ideally be using two forms of contraception (e.g. Combined oral contraceptive pill and condoms)
• dry skin, eyes and lips/mouth: the most common side-effect of isotretinoin
• low mood*
• raised triglycerides
• hair thinning
• nose bleeds (caused by dryness of the nasal mucosa)
• intracranial hypertension: isotretinoin treatment should not be combined with tetracyclines for this reason
• photosensitivity

Question 13

DDx for acne

Answer 13

rosacea
perioral dermatitis
folliculitis and boils
drug-induced acne
keratosis pilaris