Thursday, November 24, 2016

Acne Vulgaris - Brief Discussion

Introduction: Acne vulgaris is a common skin disorder which usually occurs in adolescence. It typically affects the face, neck and upper trunk and is characterised by the obstruction of the pilosebaceous follicle with keratin plugs which results in comedones, inflammation and pustules.

Epidemiology: affects around 80-90% of teenagers, 60% of whom seek medical advice. Acne may also persist beyond adolescence;

Etiology And Pathophysiology : is multifactorial

  • Follicular epidermal hyperproliferation resulting in the formation of a keratin plug.
  • This in turn causes obstruction of the pilosebaceous follicle. 
  • Activity of sebaceous glands may be controlled by androgen, although levels are often normal in patients with acne
  • Colonisation by the anaerobic bacterium Propionibacterium acnes
  • Inflammation
Clinical Features: Acne is a disease of the pilosebaceous unit. 
Several different types of acne lesions are usually seen in each patient

Comedones are due to a dilated sebaceous follicle
  • if the top is closed a whitehead is seen
  • if the top opens a blackhead forms
Inflammatory lesions form when the follicle bursts releasing irritants
  • papules
  • pustules
An excessive inflammatory response may result in:
  • nodules
  • cysts
This sequence of events can ultimately cause scarring
  • icepick scars
  • hypertrophic scars
In contrast, drug nduced acne is often monomorphic (e.g. pustules are characteristically seen in steroid use)
Acne fulminans is very severe acne associated with systemic upset (e.g. fever). Hospital admission is often required and the condition usually responds to oral steroids.

Classification Of Acne Based On Severity Of Symptoms: Acne may be classified into:
1. Mild: open and closed comedones with or without sparse inflammatory lesions
2. Moderate acne: widespread noninflammatory lesions and numerous papules and pustules
3.Severe acne: extensive inflammatory lesions, which may include nodules, pitting, and scarring.

Management: A simple management scheme often used in the treatment of acne is as follows:
  • single topical therapy (topical retinoids, benzyl peroxide)
  • topical combination therapy (topical antibiotic, benzoyl peroxide, topical retinoid)
  • oral antibiotics: e.g. Oxytetracycline, doxycycline. Improvement may not be seen for 34 months. Minocycline is now considered less appropriate due to the possibility of irreversible pigmentation. Gram negative folliculitis may occur as a complication of longterm antibiotic use high dose - oral trimethoprim is effective if this occurs
  • oral isotretinoin: only under specialist supervision
  • There is no role for dietary modification in patients with acne.
You may find the following article interesting and useful as well:

No comments:

Post a Comment