The common type of acne is called acne vulgaris. It mainly affects adolescents but may persist or even become more severe in adulthood.
What are the clinical features of acne vulgaris?
Acne is easy to recognise because it is so common; nearly all of us have it at some time or another. It most often affects the face, but it may spread to involve the neck, chest, back and sometimes even more extensively.
Individual lesions are centred on the pilosebaceous unit, ie the hair follicle and its associated oil gland. Several types of acne spots occur, often at the same time.
- Open and closed comedones (blackheads and whiteheads)
- Papules (small, tender red bumps)
- Pustules (white or yellow ‘squeezable’ spots)
- Nodules (large painful red lumps)
- Pseudocysts. These are cyst-like fluctuant swellings
- Excoriations (picked or scratched spots)
- Erythematous macules (red marks from recently healed spots, best seen in in fair skin)
- Pigmented macules (dark marks from old spots, mostly affecting those with dark skin)
- Scars or various types
Individual acne lesions usually last less than two weeks but the deeper papules and nodules may persist for months. Many acne patients also have oily skin (seborrhoea).
More images of acne ...
Acne may be classified as mild, moderate or severe1. Comedones and inflammatory lesions are usually considered separately.
- <20 comedones
- <15 inflammatory lesions
- Or, total lesion count <30
- 20-100 comedones
- 15-50 inflammatory lesions
- Or, total lesion count 30-125
- >5 pseudocysts
- Total comedo count >100
- Total inflammatory count >50
- Or total lesion count >125
Many dermatologists assess the severity of a patient's acne more precisely by using a grading scale, such as the one developed by the Leeds' group. The inflammatory lesions are compared with a set of standard photographs to determine the grade, which may be 1 (very mild) to 12 (exceptionally severe).
In clinical trials evaluating acne treatment, the numbers of uninflamed and inflamed lesions are carefully counted at regular intervals. It is remarkably difficult to count consistently.
What is the treatment for acne vulgaris?
Which treatment is best for acne vulgaris depends on the patient's age and sex, the extent and the severity of the acne, how long it has been present, and response to previous treatments.
- Treatment for mild acne includes topical anti-acne preparations, lasers and lights
- Treatment for moderate acne adds acne antibiotics such as tetracyclines and/or antiandrogens such as birth control pill
- Treatment for severe acne may require a course of oral isotretinoin.
- Lehmann HL, Robinson KA, Andrews JS, Holloway V, Goddman SN. Acne therapy: a methodological review. J. Am. Acad. Dermatol. 47, 231-240 (2002)
On DermNet NZ:
On other websites:
- Acne Vulgaris – Medscape Reference
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