acne vulgaris

Last edited 08/2021 and last reviewed 10/2021

Acne vulgaris is a common condition, which affects most people at some point in their lives (1).

Acne vulgaris is a common, chronic, inflammatory disease of the pilosebaceous unit.

This is a polymorphic eruption primarily of the face, which usually occurs in adolescents during puberty. It also occurs on the upper trunk and neck. It is characterised by the obstruction of the pilosabaceous follicle with keratin plugs. This results in comedones (the primary non inflammatory lesions), inflammation and pustules.

  • nearly 90% of teenagers suffer from acne, and half of them will continue to experience symptoms as adults (2)
    • peak incidence is 13-16 years, although it may continue into the 20's, 30's and later
    • females with polycystic ovary syndrome or those with excess cortisol (e.g. steroid use) are prone
  • by age 40 years, 1% of men and 5% of women still have lesions (3)
  • acne has clear detrimental effects on a psychosocial level and can lead to permanent scarring
  • a common presenting complaint in primary care, accounting for more than 3.5 million annual visits to General Practitioners in the UK (4)

The condition may be triggered by an over-responsiveness of the sebaceous glands to the effects of androgenic hormones which results in an increase in sebum production (1). The anaerobic bacterium, Propionobacterium acnes has an uncertain role. It may colonize the comedones, resulting in inflammation (1).

Occurrence before the onset of puberty requires further investigation to exclude underlying adrenal pathology.

Acne vulgaris can be broadly categorized into:

  • mild
  • moderate
  • severe

Click here for an example image of this condition

Differential diagnoses include rosacea, folliculitis, angiofibromas, perioral dermatitis, and keratosis pilaris.

Original contributor: Dr Maryanne Hammon (GP; 24/3/14)