Acne and rosacea


Acne goes with adolescence, a term derived from the Greek “acme” or prime of life.

The young girl who is desperately aware of the smallest comedo and the young man, with his face or back a battlefield of acne cysts and scars, are familiar to us all.

Both need treatment and help in coming to terms with their condition.

What is acne?

Acne lesions develop from the sebaceous glands associated with hair follicles on the face, external auditory meatus, back, chest, and anogenital area. (Sebaceous glands are also found on the eyelids and mucosa, prepuce and cervix, where they are not associated with hair follicles.)
The sebaceous gland contains holocrine cells that secrete triglycerides, fatty acids, wax esters, and sterols as “sebum”.

The main changes in acne are:

(1) an increase in sebum secretion;

(2) thickening of the keratin lining of the sebaceous duct, to produce blackheads or comedones the colour of blackheads is due to melanin, not dirt;

(3) an increase in Propionibacterium acnes bacteria in the duct;

(4) an increase in free fatty acids;

(5) inflammation around the sebaceous gland, probably as a result of the release of bacterial enzymes.

Underlying causes

There are various underlying causes of these changes.

Hormones

Androgenic hormones increase the size of sebaceous glands and the amount of sebum in both male and female adolescents.

Oestrogens have the opposite effect in prepubertal boys and eunuchs.

In some women with acne there is lowering of the concentration of sex hormone binding globulin and a consequent increase in free testosterone concentrations.

There is probably also a variable increase in androgen sensitivity.

Oral contraceptives containing more than 50 micrograms ethinyloestradiol can make acne worse and the combined type may lower sex hormone binding globulin concentrations, leading to increased free testosterone.

Infantile acne occurs in the first few months of life and may last some years.

Apart from rare causes, such as adrenal hyperplasia or virilising tumours, transplacental stimulation of the adrenal gland is thought to result in the release of adrenal androgens but this does not explain why the lesions persist.

It is more common in boys.

Fluid retention

The premenstrual exacerbation of acne is thought to be due to fluid retention leading to increased hydration of and swelling of the duct.

Sweating also makes acne worse, possibly by the same mechanism.

Diet

In some patients acne is made worse by chocolate, nuts, and coffee or fizzy drinks.

Seasons

Acne often improves with natural sunlight and is worse in winter.

The effect of artificial ultraviolet light is unpredictable.

External factors

Oils, whether vegetable oils in the case of cooks in hot kitchens or mineral oils in engineering, can cause “oil folliculitis”, leading to acne-like lesions.

Other acnegenic substances include coal tar, dicophane (DDT), cutting oils, and halogenated hydrocarbons (polychlorinated biphenols and related chemicals).

Cosmetic acne is seen in adult women who have used cosmetics containing comedogenic oils over many years.

Iatrogenic factors

Corticosteroids, both topical and systemic, can cause increased keratinisation of the pilosebaceous duct.

Androgens, gonadotrophins, and corticotrophin can induce acne in adolescence.

Oral contraceptives of the combined type can induce acne, and antiepileptic drugs are reputed to cause acne.

Types of acne

Acne vulgaris

Acne vulgaris, the common type of acne, occurs during puberty and affects the comedogenic areas of the face, back, and chest.

There may be a familial tendency to acne.

Acne vulgaris is slightly more common in boys, 30–40% of whom have acne between the ages of 18 and 19. In girls the peak incidence is between 16 and 18 years.

Adult acne is a variant affecting 1% of men and 5% of women aged 40.

Acne keloidalis is a type of scarring acne seen on the neck in men.

Patients with acne often complain of excessive greasiness of the skin, with “blackheads”, “pimples”, or “plukes” developing.

These may be associated with inflammatory papules and pustules developing into larger cysts and nodules. Resolving lesions leave inflammatory macules and scarring.

Scars may be atrophic, sometimes with “ice pick” lesions or keloid formation.

Keloids consist of hypertrophic scar tissue and occur predominantly on the neck, upper back, and shoulders and over the sternum.

Acne excoreé

The changes of acne are often minimal but the patient, often a young girl, picks at the skin producing disfiguring erosions.

It is often very difficult to help the patient break this habit.

Infantile acne

Localised acne lesions occur on the face in the first few months of life.

They clear spontaneously but may last for some years.

There is said to be an associated increased tendency to severe adolescent acne.

Acne conglobata

This is a severe form of acne, more common in boys and in tropical climates.

It is extensive, affecting the trunk, face, and limbs.

In “acne fulminans” there is associated systemic illness with malaise, fever, and joint pains.

It appears to be associated with a hypersensitivity to P. acnes.

Another variant is pyoderma faciale, which produces erythematous and necrotic lesions and occurs mainly in adult women.

Gram negative folliculitis occurs with a proliferation of organisms such as klebsiella, proteus, pseudomonas, and Escherichia coli.

Occupational

Acne-like lesions occur as a result of long term contact with oils or tar as mentioned above.

This usually results from lubricating, cutting, or crude oil soaking through clothing.

In chloracne there are prominent comedones on the face and neck.

It is caused by exposure to polychlortriphenyl and related compounds and also to weedkiller and dicophane.

Treatment of acne

In most adolescents acne clears spontaneously with minimal scarring.

Reassurance and explanation along the following lines helps greatly:

(1) The lesions can be expected to clear in time.

(2) It is not infectious.

(3) The less patients are self conscious and worry about their appearance the less other people will take any notice of their acne.

It helps to give a simple regimen to follow, enabling patients to take some positive steps to clear their skin and also an alternative to picking their spots.

Patients with acne should be advised to hold a hot wet flannel on the face (a much simpler alternative to the commercial “Facial saunas”), followed by gentle rubbing in of a plain soap.

Savlon solution, diluted 10 times with water, is an excellent alternative for controlling greasy skin.

There are many proprietary preparations, most of which act as keratolytics, dissolving the keratin plug of the comedone.

They can also cause considerable dryness and scaling of the skin.

Benzoyl peroxide in concentrations of 1–10% is available as lotions, creams, gels, and washes.
Resorcinol, sulphur, and salicylic acid preparations are also available.

Vitamin A acid as a cream or gel is helpful in some patients.

A topical tretinoin gel has recently been introduced.

Ultraviolet light therapy is less effective than natural sunlight but is helpful for extensive acne.

It is a helpful additional treatment in the winter months.

Oral treatment. The mainstay of treatment is oxytetracycline, which should be given for a week at 1 g daily then 500 mg (250 mg twice daily) on an empty stomach.

Minocycline or doxycycline are alternatives that can be taken with food. Perseverance with treatment is important, and it may take some months to produce an appreciable improvement.

Erythromycin is an alternative to tetracycline, and co-trimoxazole can be used for Gram negative folliculitis.

Tetracycline might theoretically interfere with the absorption of progesterone types of birth control pill and should not be given in pregnancy.

Topical antibiotics. Erythromycin, the tetracyclines, and clindamycin have been used topically.

There is the risk of producing colonies of resistant organisms.

Antiandrogens. Cyproterone acetate combined with ethinyloestradiol is effective in some women; it is also a contraceptive.

Synthetic retinoids. For severe cases resistant to other treatments these drugs, which can be prescribed only in hospital, are very effective and clear most cases in a few months.

13-cis-Retinoic acid (isotretinoin) is usually used for acne.

They are teratogenic, so there must be no question of pregnancy, and can cause liver changes with raised serum lipid values.

Regular blood tests are therefore essential.

A three month course of treatment usually gives a long remission.

Recently topical isotretinoin gel has been introduced.

Residual lesions, keloid scars, cysts, and persistent nodules can be treated by injection with triamcinolone or freezing with liquid nitrogen.

For severe scarring dermabrasion can produce good cosmetic results.

This is usually carried out in a plastic surgery unit.

Rosacea

Rosacea is a persistent eruption occurring on the forehead and cheeks.

It is more common in women than men.

There is erythema with prominent blood vessels. Pustules, papules, and oedema occur.

Rhinophyma, with thickened erythematous skin of the nose and enlarged follicles, is a variant.

Conjunctivitis and blepharitis may be associated.

It is usually made worse by sunlight.

Rosacea should be distinguished from:

• Acne, in which there are blackheads, a wider distribution, and improvement with sunlight.

Acne, however, may coexist with rosacea hence the older term “acne rosacea”.

• Seborrhoeic eczema, in which there are no pustules and eczematous changes are present.

• Lupus erythematosus, which shows light sensitivity, erythema, and scarring but no pustules.
• Perioral dermatitis, which occurs in women with pustules and erythema around the mouth and on the chin.

There is usually a premenstrual exacerbation. Treatment is with oral tetracyclines.

Treatment

The treatment of rosacea is with long term courses of oxytetracycline, which may need to be repeated. Topical treatment along the lines of that for acne is also helpful.

Topical steroids should not be used as they have minimal effect and cause a severe rebound erythema, which is difficult to clear.

Avoiding hot and spicy foods may help.

Recent reports indicate that synthetic retinoids are also effective.





This article comes from Medical Encyclopedia

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