Acne vulgaris Flashcards
What is acne vulgaris?
Common skin disorder - usually occurs in adolescence
Typically affects the face, neck and upper trunk
Characterised by obstruction of pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules
What is the epidemiology of acne vulgaris?
Affects ~ 80-90% of teenagers (of whom 60% seek medical advice)
Can also persist beyond adolescence - 10-15% of females and 5% of males > 25 years old are affected
What is the pathophysiology of acne vulgaris?
Follicular epidermal hyperproliferation results in formation of keratin plug
Causes obstruction of pilosebaceous follicle - the activity of the sebaceous glands may be controlled by androgens, although androgen levels are often normal in patients with acne
Colonisation by anaerobic bacterium Proprionibacterium acnes occurs
Leads to inflammation
What are the features of acne?
Comedones - due to dilated sebaceous follicle
- whitehead = top is closed
- blackhead = top opens
Inflammatory lesions form (i.e., pustules and papules) when follicles burst releasing irritants
Excessive inflammatory response may result in:
- nodules
- cysts
Drug induced acne = monomorphic (e.g., pustules characteristically seen in steroid use)
Acne fulminans - severe acne associated with systemic symptoms (e.g., fever). Hospital admission often required and usually responds to oral steroids
What is the classification of acne?
Mild = open and close comedones +/- sparse inflammatory lesions
Moderate = widespread non-inflammatory lesions and numerous papules and pustules
Severe = extensive inflammatory lesions - may include nodules, pitting and scarring
What advice should you give patients with acne?
Avoid over-cleaning the skin which may cause dryness and irritation (acne is not caused by poor skin hygiene)
Use non-alkaline (skin pH neutral or slightly acidic) synthetic cleaning products BD on the skin
Avoid oil based comedogenic creams and makeup
If they use makeup, remove it at the end of the day
Persistent picking and itching can lead to scarring
Acne Tx may irritate the skin, especially at the start
Not enough evidence that specific diets causes acne, but advice them to maintain a healthy balanced diet
What is the Tx for mild to moderate acne?
12-week course of one of the following 1st line options to be applied OD in the evening:
- fixed combination of topical adapalene with topical benzoyl peroxide (0.1% or 0.3% adapalene with 2.5% benzoyl peroxide)
- fixed combination of topical tretinoin and topical clindamycin (0.025% tretinoin with 1% clindamycin)
- fixed combination of topical benzoyl peroxide and topical clindamycin (3% or 5% benzoyl peroxide with 1% clindamycin)
If 1st line options for mild to moderate acne are contraindicated or the person wishes to avoid using a topical retinoid or an antibiotic, what Tx can be given instead?
Topical benzoyl peroxide - monotherapy
If skin irritation occurs with topical Tx what may you have to do?
Reduce concentration or application frequency of topical treatments
What is the Tx for moderate to severe acne?
12-week course of one of the following 1st line options:
- fixed combination of topical adapalene with topical benzoyl peroxide to be applied OD in the evening
- fixed combination of topical tretinoin with topical clindamycin to be applied OD in the evening
- fixed combination of topical adapalene with topical benzoyl peroxide to be applied OD in the evening, together with either oral lymecycline 408mg OD or oral doxycycline 100mg OD
- Topical azelaic acid (15% or 20%) BD with either oral lymecycline 408mg OD or oral doxycycline 100mg OD
For people who cannot tolerate or have contraindications to oral lymecycline or oral doxycycline, what can you replace them with?
Trimethoprim
Macrolide (e.g., erythromycin)
What other class of drugs can be considered in combination with topical agents as an alternative to systemic antibiotics in women with moderate to severe acne?
Combine oral contraceptives
Preferably 3rd and 4th generation combined oral contraceptives
3rd generation examples = desogestrel (Gedarel, Marvelon, Mercilon), gestodene (Femodene) or drospirenone (Eloine, Lucette, Yacella, Yasmin, Yiznell), norelgestromin (Evra) and etonogestrel (Nuvaring)
4th generation examples = contain either the same estrogen ethinyl estradiol, plus a new progesterone drospirenone (Yasmin), or a different estrogen 17 B estradiol (a natural estrogen) with nomegestrol acetate (Zoely), or estradiol valerate (a natural estrogen) and dienogest (Qlaira)
Which types of oral contraceptives may exacerbate acne?
Oral progesterone only pills
Progestin implants with androgenic activity
What other type of Tx for moderate to severe acne apart from oral contraceptives may be considered in moderate to severe acne?
Co-cyprindiol (Dianette®) or other ethinylestradiol/cyproterone acetate-containing products
Where other treatments have failed
Require careful discussion of the risks and benefits with the patient
Use should be discontinued 3 months after acne has been controlled and prescription guided by the UK Medical Eligibility Criteria for Contraceptive Use and the Summary of Product Characteristics for the individual product
What types of treatment should NOT be used for acne?
Monotherapy with topical antibiotic
Monotherapy with oral antibiotic
Combined therapy with topical and oral antibiotics
