Key points

• Acne is caused by hair follicles becoming clogged up:

  • Blocked are known as comedones:
  • Closed = whitehead
  • Open = blackheads
  • These are non-inflamed lesions
  • Inflammatory lesions = papules, pustule, nodules and cysts
• Pathogenesis:

  •Follicular hyperkeratinization: skin cells (keratinocytes) inside follicles shed abnormally and clump together

  •Increased sebum production: sebaceous glands within follicles produce too much sebum (secondary to androgens which is why acne often occurs around puberty) – the excess sebum mixes with the dead skin cells further plugging the follicle

  •Proliferation of bacteria (e.g. cutibacterium acnes)- this bacteria thrives in these conditions:

  1. The sebum is an energy source for it
  2. The blocked pore creates an oxygen free (anaerobic environment) that it flourishes in 
• Urgent same day referral:

  • Acne fulminans:
  • Very severe form of acne conglobata associated with systemic symptoms
  • Nearly always affects adolescent males
• Acne fulminans:

  • Abrupt onset
  • Inflammatory and ulcerated nodular acne on chest and back
  • Very painful
  • Bleeding crusts over the ulcers on upper trunk
  • Fluctuating fever
  • Painful joints
  • Malaise
  • Hepatosplenomegaly
• Refer to dermatology:

  • Diagnostic uncertainty
  • Nodulo-cystic acne
  • Acne conglobate
• Consider referral to dermatology:

  • Mild to moderate acne that has not responded to 2 treatments
  • Moderate to severe acne that has not responded to treatment including oral antibiotics
  • Acne with scarring
  • Acne with persistent pigmentary changes
  • Acne of any severity that is causing or contributing to psychological distress
• •Nodulocystic acne- severe form of acne characterised by nodules and cysts that typically resolve with scarring

  •Conglobate acne: A rare and severe variant of nodulocystic acne. Most often occurs in men. Presents with extensive inflammatory papules, suppurative nodules which may coalesce to form sinuses, and cysts