Author: Dr Amanda Oakley, Dermatologist, Hamilton, New Zealand, July 2014.

What is acne?

Acne is a common chronic disorder affecting the hair follicle and sebaceous gland, in which there is expansion and blockage of the follicle and inflammation. There are several variants.

Who gets acne?

Acne affects males and females of all races and ethnicities. It is prevalent in adolescents and young adults, with 85% of 16-18 year olds affected. However, it may sometimes occur in children and adults of all ages.

What causes acne?

Acne is due to a combination of factors. The exact mechanisms are not fully understood.

Flares of acne can be provoked by:

What are the clinical features of acne?

Acne is often confined to the face but it may involve neck, chest and back.

It is characterised by:

Severity is classified as mild, moderate or severe.

What tests are necessary in acne?

In most cases, tests are unnecessary. If features are atypical consider:

See more images of acne ...

What is the treatment for acne?

Mild acne

Moderate acne

Severe acne

What is the outlook for acne?

Treatment with isotretinoin can lead to long-term remission in many patients.

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