A23. Acne and its treatment

• Common acne = Acne vulgaris
• (comedo/comedones = plugged hair follicle (pore))
• Risk factors
  • Genetic predisposition
  • Hormonal changes
    • Puberty
    • Menstrual cycle
  • Certain foods
  • Smoking
  • Skin products that block pores
• Pathomechanism
  • Hyperactivity of sebaceous glands
  • Hyperkeratosis of follicular keratinocytes
  • Bacterial hypercolonization
    • Propionibacterium acnes (= cutibacterium acnes)
  • Inflammation
• Clinical features
  • On face, shoulders, upper chest, back
  • Primary lesions
    • Non-inflammatory acne – comedonal acne
      • Closed comedones = whiteheads
        • Small papules that contain whitish material
        • The whitish material is keratin and sebum
      • Open comedones = blackheads
        • Small papules with black material
        • The black material is oxidized keratin and sebum
    • Inflammatory acne
      • Papular acne
      • Pustular acne
      • Nodular acne (> 5 mm)
  • Secondary lesions
    • Erythema
    • Hyperpigmentation
    • Scarring
      • Hypertrophic scars
      • Depressed scars
      • Pitted scars
• Special types of acne
  • Acne inversa = hidradenitis suppurativa
    • Inflammation of hair follicles due to physical blockage by skin folds, etc
  • Acne fulminans
    • Sudden onset, very severe acne
    • In teenage boys
• Diagnosis
  • Anamnesis
  • Clinical examination
  • Laboratory examinations
    • Exclude hyperandrogenism, like PCOS, CAH, androgen-producing tumors
• Treatment
  • Options
    • Topical benzoyl peroxide
      • Comedolytic
      • Bactericidal
    • Retinoids
      • Oral or topical
      • Tretinoin, isotretinoin, adapalene
      • Normalize keratinocyte differentiation
      • Decrease sebum production
      • Highly teratogenic
        • Females must produce negative pregnancy test and use at least one, optimally two methods of contraception
      • Hepatotoxic
        • Liver enzymes, cholesterol must be monitored
    • Antibiotics
      • Oral (doxycycline, minocycline)
      • Topical (erythromycin, clindamycin)
      • Bactericidal
      • Decrease inflammation
    • Oral contraceptives
      • In females
      • Can be added in treatment failure
    • Topical combination therapy
      • Benzoyl peroxide + topical retinoid
      • Benzoyl peroxide + topical antibiotic
      • Benzoyl peroxide + topical retinoid + topical antibiotic
  • Treatment algorithm
    • Mild cases
      • Topical benzoyl peroxide
      • Topical retinoid
      • Topical combination therapy
    • Moderate cases
      • Topical combination therapy
      • Oral antibiotic + topical combination therapy
    • Severe cases
      • Oral retinoid