What is ACNE VULGARIS?
Dr Ang Por
Associate Consultant
NATIONAL SKIN CENTRE
Acne vulgaris is a common skin disorder of the pilosebaceous unit (sebaceous gland and adjoining hair follicle, characterised by increased oil production and development of comedones such as blackheads, whiteheads) and inflammatory lesions. These occur predominantly on the face, chest and back.
What causes acne?
It is due to an end-organ hyper-responsiveness to androgens. Four factors are important for the pathogenesis of acne:
Increased sebum production
Blockage of pilosebaceous duct
Propionibacterium acnes
Inflammation
There is an increase in sebum production by the sebaceous gland in response to the male hormone testosterone. This explains why acne usually starts around puberty and why certain females with abnormally high male hormones have more severe acne. Most acne patients are normal and healthy. However, if the patient has features of hirsutism or irregular menstruation, an endocrinopathy should be looked for eg: polycystic ovarian disease.
Besides seborrhoea, there is also ductual hypercornification ie proliferation of the keratinocytes around the pilosebaceous duct, causing blockage of the duct. When this happens, comedones are formed. Bacterial inflammation also plays an important role in the pathogenesis of acne. The bacterium Propionibacterium acnes (P.acnes) act on the sebum in the hair follicle and break it down to fatty acids which are released into the surrounding skin. This causes the inflammatory lesions of papules, pustules, nodules and cysts. Scars may result from the inflammatory lesions; there may be atrophic scars (pits), hypertrophic scars or keloids
Closed Comedones and Open Comedones
Who gets acne?
The onset of acne is usually at or just beyond puberty. The acne life span ranges from 6-14 years and sometimes longer. Women can develop acne in their late twenties or thirties (acne tarda). Very rarelt infantile acne can occur; this clears in 2-4 years. It is also important to remember that some environmental factors can cause acne such as:
Drugs eg topical or systemic steroids, anti-epileptic or anti-tuberculous drugs
Occupational factors eg oils, tars
These may appear monomorphic or distributed over the areas of contact.
How to advise acne patients?
Acne is treatable
Acne is a slow responding disorder. Systemic antibiotics are given for at least 6 months, and intermittent courses may be required. Topical treatment is likely for the whole of the acne life span. 40% improvement is anticipated at 2 months, 60% at 4 months and 80% or more at 6 months or treatment. Compliance is important and must be emphasized
Acne will resolve one day but scars are permanent and difficult to treat
Others: There is no evidence that dietary restriction helps acne. Cosmetics should be water-based and oil free and kept to a minimum. Facials are not harmful unless there is excessive squeezing of lesions which may result in scars. Excessive face washing will not cause more oil production.
How to treat acne?
For mild acne, ie mainly comedones and a few papules or pustules, topical treatment may suffice. First line therapy include bacteriostatic agents like acne cream (suphur, resorcinol) and benzoyl peroxide. Retinoids are comedolytic and are helpful for comedonal acne. These include tretinoin (eg Retin A, Retacnyl, Stieva A), isotretinoin (Isotrex) and adapalene (Differin) a retinoid-like substance with less irritation. For inflammatory lesions, antibiotics like clindamycin (eg Dalacin), erythromycin (eg T Stat, Eryderm, Eryacne) are prescribed. An antibacterial face wash (eg triclosan, benzoyl peroxide) is helpful. Some degree of exfoliation is useful especially for comedones and this can be achieved with over-the-counter alpha hydroxy acid products (AHA solution for oily and acne prone skin) or chemical peels done by doctors.
Moderate acne i.e. many papules and pustules should be treated with a course of antibiotics. These include doxycycline 100 mg bd, tetracycline 500 mg bd, erythromycin 500 mg bd, cotrimoxazole-trimethoprim (Bactrim) 2 tablets bd and minocycline 100 mg bd. If there is no response by 6 weeks, the antibiotics should be changed after non compliance has been excluded. When the acne is controlled, the dosage of the antibiotics is tapered down before stopping. The effectiveness of oral contraceptives is reduced with antibiotics so precautions should be taken eg additional barrier method If the patient is sexually active and desires contraception, Diane-35, a contraceptive, given for 18 months, is useful.
Sever acne ie nodulo-cystic ane should be treated early with isotretinoin (Roaccutane) to prevent scarring. This is given at a dose of 0.5 mg/kg/day up to a cumulative and minimum dosage of 100-120 mg/kg to minimise relapse. The side effects eg dryness, cheilitis and complications eg teratogenicity hepatitis, hyperlipidaemia must be explained before treatment. Fasting lipids and liver function tests are indicated before treatment. Pregnancy must be avoided during the duration of isotretinoin therapy until one menstrual cycle after stopping the drug.
Acne Scars Severe Acne
Adjunctive treatment for acne
Intralesional triamcinolone acetonide injections of acute inflammed cysts will aid resolution. Persistent macromedones can be removed with expression or light electrocautery.
How to apply topicals?
The cream, gel, or solution should be applied to the whole area prone to acne and not just individual lesions. All acne products cause a certain degree of peeling and dryness. If the dermatitis is excessive, the treatment can be stopped and then restarted over a small area first. If no problems occur, the topical can be increased to bigger areas. A moisturising cream may help the dryness. If the dermatitis persists, a change in product may be indicated.
How to take tablets?
Tetracycline and erythromycin are taken twice daily 30 minutes before food with water, not milk. If the patient forgets, he should quickly take it as soon as he remembers. Doxycycline, moinocycline and trimethoprim are taken at the end of a meal.
How to treat pregnant ladies with acne?
Topical treatment with erythromycin or benzoyl peroxide or systemic erythromycin.
How to treat scars?
It is imperative that the patient does not squeeze, pick or scratch the acne lesions. Some patients especially females, have a compulsive tendency to do this (acne excoriee). Scars are not treated by topicals or antibiotics. There are two types of scars:
1) Pitted / atrophic scars
Superficial scars will improve with time or with chemical peels. Deep scars are treated by excision, laser resurfacing, dermabrasion, collagen injection or a combination of the above
2) Hypertrophic scars or keloids
These often occur over the jawline, neck, chest and back. These are treated with monthly intralesional triamcinolone acetonide injections (Kenacort) 10mg/DL until complete flattening. There is no good way or eradicating scars once they are formed. Prevention is still the best.
Good Skincare Hygiene and Habits
Besides using the medications prescribed by the doctor to treat your acne problems, you should also exercise good skincare hygiene and habits to avoid worsening the condition. These are some measures you can take to prevent your acne problems from worsening:
Clean your skin gently with a suitable cleanser twice a day. Preferably use a product that contains antiseptic like AHA Facial Wash for Oily and Acne-Prone Skin. Do not scrub your skin excessively using strong detergent soaps as this could worsen your acne problems
Avoid frequent rubbing or touching of acne prone skin, as this could introduce and encourage the growth of bacteria within the pores and hair follicles of the skin.
Do not squeeze, pick, scratch, or rub your skin. Scars may form if you squeeze pimples. Wash your hands more frequently and avoid putting your fingers and hands to your face unnecessarily. Do not rest your face on your hands while you read, study, or watch TV.
Avoid Suntanning. Although a suntan or sunburn that reddens the skin can make blemishes less visible and make the skin feel drier for a little while, the benefits, however, are only temporary. The sun can seriously damage skin, promote premature aging of skin, and may cause skin cancer. Furthermore, many of the mediacations used to treat acne also make a person more prone to sunburn.
People being treated for acne often need to change some of the cosmetics they use. All cosmetics, such as foundation, blush, eye shadow and moisturizers, should be oil free or water-based. It is also advisable not to use cosmetics too heavily or too often.
Avoid Stress.
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