Acneiform Eruptions Flashcards
What is the pathophysiological mechanism of inflammation in acne?
- Hyperkeratosis occurs due to hyperproliferation of ductal keratinocytes or reduced separation of ductal corneocytes which leads to blockage of pilosebaceous duct
- Sebum excretion increases via androgen stimulation and builds up
- Propionibacterium acnes overpopulates duct along with shed keratin and sebum
- Stimulates inflammatory mediators
How does sebum excretion rate change in acne?
Increases (androgen stimulates it)
increases in puberty
What are the 2 types of comedones?
Open (blackheads)
Closed (whiteheads)
What are blackheads?
Dilated keratin filled follicles which appear as black papules due to keratin debris
What are whiteheads?
Accumulation of sebum and keratin deeper in the pilosebaceous ducts
What is the most common peak age for acne vulgaris?
15-18yrs (90% of teens)
What happens to the squamous epithelium in acne?
Hypercornification/hyperkeratinisation - develops into tough protective layers
What are the 3 variants of acne?
Mild
Moderate
Severe
How is mild acne described?
Non-inflammatory
Open + closed comedones
Lesions <30; <15 inflammatory
How is moderate acne described?
Inflammatory (papules, pustules, nodules, cysts)
20-100 comedones
Lesions 30-125; inflammatory 15-50
What can early treatment of moderate acne prevent?
Scarring
How is severe acne described?
> 5 pseudocysts
Comedones >100
Lesions >125; Inflammatory >50
Severe acne is difficult to treat, may need lasers, but what is left once it is treated?
Permanent scarring and post-inflammatory pigmentation
Give 3 acne variants
Acne Fulminans
Drug induced acne
Acne excoriee
How is acne fulminans characterised?
Most severe form of cystic acne
Abrupt onset of nodular and suppurative acne with systemic manifestations
What systemic manifestations accompany acne fulminans?
Fever
Arthralgias
Myalgias
Hepatosplenomegaly
What medications cause drug induced acne?
Anabolic steroids Corticosteroids Phenytoin Lithium Isoniazid
What is the cause of acne excoriee?
Neurotic excoriation of papules and comedones leaving crusted lesions which may scar
Why might you enquire about menstrual history in acne?
Polycystic Ovary Syndrome
What are some topical treatments for acne?
Topical retinoids
Benzoyl peroxide
Topical abx (clindamycin/erythromycin)
Azelaic acid
What are some oral treatments for acne?
Abx tablets (lymecycline, tetracycline)
Combined oral contraceptive pill in women
Isotretinoin (last resort)
What populations is rosacea most common in?
3rd and 4th decades of life
Fair-skinned
Is there a known pathogenesis of rosacea?
No; in contrast to acne it is not associated with sebhorrhoea
What is increased in rosacea?
Sensitivity to noxious stimuli
What is the mite which is increased in number in rosacea?
Demodex folliculorum
Describe a common presentation of rosacea
Central convex areas of face affected
Episodic flushing with no sweating
Erythema/burning sensation triggered by minor irritants
Persistent tissue thickening due to oedema, fibrosis + glandular hyperplasia
What can be present in more advanced rosacea?
Papules and pustules (NO COMEDONES)
What are some triggers for rosacea?
Stress
Hot drinks
Alcohol
Spices
Give the 2 features of vascular rosacea
Recurrent blush
Telangiectasis (initially in nose)
Give some (4) features of inflammatory rosacea
Small papules/pustules
Absence of comedones
Deeper red colour compared to acne
Soft/solid facial oedema
Describe phymatous rosacea
Overgrowth of sebaceous glands
Skin swollen and smoother; pores more apparent
Lumpy surface gradually develops (nose)
What is the incidence of ocular rosacea?
50% of rosacea patients
What are some possible symptoms of ocular rosacea?
Dryness/tired eyes Oedema Tearing Pain Chalazia Corneal damage
What are the topical treatments for rosacea?
Metronidazole cream/gel (major therapy)
Azelaic acid cream/gel
Ivermectin cream
What are the non-topical treatments for rosacea?
Tetracyclines most common
Avoidance of obvious vasodilators/irritants
Surgery for rhinopymas
