Acne Vulgaris

Snapshot

  • A 25-year-old woman presents to her dermatologist’s office for acne. She reports that she had severe acne when she went through puberty. However, this resolved before she graduated from high school. In the past year, as she prepared applications for medical school, she reports that she is getting acne every month around the time of her menstruation. She also reports having worse acne when her stress levels coincide with her menstruation, though this is just speculation. On physical exam, she has no active lesions, but marked post-inflammatory hyperpigmentation consistent with the resolution of previous acne lesions.  She is started on oral contraceptives for management of her acne, along with a topical retinoid.

Introduction

  • Clinical definition
    • common chronic skin condition characterized by inflammatory and non-inflammatory lesions 
  • Epidemiology
    • incidence
      • very common
    • demographics
      • up to 85% of teenagers but can affect adults as well
      • more severe around puberty
    • location
      • face, back, neck, chest, and upper arms
    • risk factors
      • menstrual cycle
      • emotional stress
      • occlusion of skin with greasy products
      • excessive sweating
      • pregnancy
      • milk consumption
  • Etiology
    • multifactorial
      • androgen production
      • medications
        • steroids
  • Pathogenesis
    • blockage or outlet obstruction of pilosebaceous unit, forming comedones from
      • ↑ sebum production
      • abnormal desquamation of keratinocytes and its accumulation
      • colonization of bacteria Propionibacterium acnes
    • inflammatory lesions result from
      • leakage of sebum from comedones into dermis
      • secretion of proinflammatory cells by Propionibacterium acnes
    • ↑ androgen production also play a role in acne formation
  • Associated conditions
    • polycystic ovary syndrome 
    • Cushing syndrome
    • congenital adrenal hyperplasia 
  • Prognosis
    • in many cases, acne will resolve in adulthood
  • however, hormonal acne may persist

Presentation

  • Symptoms
    • nodular or cystic acne may be painful
  • Physical exam
    • inflammatory lesions
      • erythematous papules, pustules, cysts, or nodules 
    • non-inflammatory lesions are comedones, which are dilated hair follicles filled with keratin, sebum, and bacteria
      • open comedones are known as blackheads 
      • closed comedones are known as whiteheads 
    • scarring 
  • pitting and puckered indentation in skin

Studies

  • Making the diagnosis
  • most cases are clinically diagnosed

Differential

  • Hidradenitis suppurativa 
  • Rosacea 
  • Folliculitis

Treatment

  • Management approach
    • multiple factors go into the decision to treat acne, including severity of acne, type of acne, presence or potential for permanent scarring, concern for side effects, and adherence to therapy
  • Medical
    • benzoyl peroxide
      • topical or wash
        • indication
          • for mild comedonal acne
    • antibiotics
      • topical
        • indications
          • for mild non-comedonal acne
          • used in conjunction with benzoyl peroxide or topical retinoid
        • drugs
          • clindamycin
          • erythromycin
      • systemic
        • indications
          • for mild to moderate non-comedal acne
          • should not be used long-term or as monotherapy
        • drugs
          • tetracycline
          • minocycline
          • doxycycline
    • retinoids      
      • topical
        • indications
          • for mild to moderate acne, especially with comedones and inflammatory acne
          • often first-line when combined with an antimicrobial agent (topical or systemic)
        • drugs
          • adapalene
          • tazarotene
          • tretinoin
      • systemic
        • indications
          • for moderate to severe acne, especially cystic acne
          • for patients with existing or potential for permanent scarring
          • contraindicated in pregnancy
        • drugs
          • isotretinoin 
            • adverse effects include teratogenicity, hypertriglyceridemia, idiopathic intracranial hypertension, hepatotoxicity, cheilitis, and photosensitivity  
            • Requires measurement of urine beta-hCG (pregnancy test) before administration due to teratogenicity 
    • hormonal therapy
      • indications
        • for severe acne or acne refractory to other therapy
        • for acne that seem to correspond with menstrual cycle
      • drugs
        • oral contraceptives
  • spironolactone

Complications

  • Permanent acne scarring and cosmetic disfigurement