13.03.07 Dermatology teaching - Acne

Classification

• • Vulgaris

    • Standard

  • Excoriee

    • Scratched

  • Conglobata

  • Fulmigans

    • Scarring

    • Secondary infection

    • Death

  • Infantile

Comedones

• • Open

    • Sebum oxidation => Blackhead

  • Closed

    • Accumulation => Inflammation

    • Infection (Propionibacterium acnes)

Treatments

• • Topical

    • Retionoids - Good for comodomal acne

      • Adapalene

      • Retinoic acid

    • Azelaic acid

    • Antimicrobials - Good for inflammatory acne

      • Benzoyl peroxide (cf bleaching)

      • Antibiotics

        • Clindamycin

        • Erythromycin

    • Combination creams

      • Duac

      • Benzamycin

      • Isotrexin

      • Epiduo

      • Acnisal

  • Oral antibiotics

    • Combine with topical retinoid

    • Tetracyclins

      • Lymecycline

      • Oxytetracycline

      • Doxycycline

      • Minocycline

    • Erythromycin

  • Hormones

    • Dianette

      • Cyproterone acetate (anti-androgen/progestogen) and ethinylestradiol

      • As effective as COCP, but never used just for contraception

    • COCP

  • Isotretinoin (Roacutane)

    • Only dermatologists can prescribe

    • Give 120 mg/kg total dose, over 4 months

    • Side effects

      • Pregnancy category X

      • Dry skin (everywhere)

      • Photosensitivity

      • Joint pain

      • Nosebleeds

      • Can make acne worse initially

        • => Acne fulmigans

        • Cover with low-dose pred.

      • ? Depression (no evidence but be careful)

Triggers

• • Diet

    • Generally no

    • ? Low glycaemic index may help

    • ? Milk / Fatty foods

  • Stress

    • Doesn't trigger new eruptions

  • Facial hygiene

    • Wash OD, non-oily

    • No more required

  • Smoking

    • No link established

  • Sweating

    • Exacerbates

  • Premenstrual

    • Exacerbates in 70% of women

Indications for patch testing

• • Contact dermatitis

  • Eczema not improving

  • Hand/foot eczema

  • Eczema unusual site

Notes

• • Androgens

    • Testosterone

    • DHT

    • Dehydroepiandrosterone sulfate (DHEAS)

      • Suphate ester of DHEA - Major circulating form

      • Made in Adrenals / Brain

      • cf pre-pubertal acne

  • Pilosebaceous

    • Epidermal invagination

    • Hair follicle, sebaceous gland, arrector pili muscle

  • All treatments take a couple of months to work

  • No COCP if migraines (thrombosis association)

  • Check for causes of raised androgens

    • PCOS - Any 2 of:

      • Oligoovulation and/or anovulation

      • Excess androgen activity

      • Polycystic ovaries (by gynecologic ultrasound)

  • Acne rosacea

    • Not real acne

    • Eryhthema

    • Papular/Pustular rash

    • No comidones (doesn't involve PSU)

  • Perioral dermatitis

    • From topical steroids

  • Chronic idiopathic urticaria

    • Appear to be allergic to everything

  • Patch testing (Type IV) vs serum IgE testing (Type I)

  • Garlic allergy