Acne vulgaris is a self-limiting disease of the pilosebaceous unit.
The cause is multifactorial.
Clinical lesions range from non-inflammatory
comedones to inflammatory papules, pustules, nodules and cysts.
Incidence of Acne vulgaris
Acne vulgaris occurs worldwide, affecting 90% of
the people at sometimes in their life.
The age of onset is at puberty.
Contrary to popular belief, acne is not confined to
teenagers. It may continue into 3rd and 4th decades
of life.
Acne is commoner and more severe in male than in
female, relating to its androgen activity.
Heredity also plays a role. If patient’s mother and
father had bad acne, the patients may too.
Sudden and profuse lesions erupting at a later age
call for investigations of the pituitary, adrenal cortex
and gonads.
Types of acne vulgaris
A. Noninflammatory lesions (comedones ):
1. Closed comedone ( whitehead ) :
when a trapped sebum and bacteria stay
below the skin surface, a whitehead is formed.
2. Open comedone ( blackhead ) :
when a trapped sebum and bacteria open to the
surface and turn black due to oxidation of melanin.
B. Inflammatory lesions:
1. Papules
2. Pustules
3. Nodules and
4. Cysts
Principle of treatment of acne vulgaris
1.To reduce the bacterial population of the hair follicles to cut down the hydrolysis of lipids (antimicrobial agents ).
2.To encourage the shedding of the follicular horny plugs to free the obstruction (comedolytic agents ).
3.To reduce the rate of sebum production, by
inhibiting the effects of androgens on the
sebaceous glands ( anti-androgens ).
4.To reduce the damaging effects of inflammation
on the skin (anti-inflammatory agents).
THERAPY OF ACNE
TOPICAL
@Benzoyl peroxide 5% gel daily
@Retinoids
Retin -A cream
Adapalene cream
@Antibiotics
Erythromycin 2% solution daily
Clindamycin 1% lotion daily
SYSTEMIC
Antibiotics:
Tetracycline: 500 mg BID
Erythromycin: 500 mg BID
Doxycicline: 50 mg daily
Azithromycin: 500 mg daily for three consecutive days in a week for 12 weeks.
Isotretinoin:
1 mg/ kg daily for 20 weeks
Hormonal therapy:
Oral contraceptive pills (Estrogen dominant).
Antiandrogens: (ciproterone acetate, spironolactone).
Note comedones, papules and pustules
Post adolescent female acne.
Papules and pustules occur, particularly on the chin, cheeks and jaw, which may be deep and painful and worse premenstrually.
Infantile acne ( milk spots ).
Transplacental maternal adrenal androgens stimulate the infantile sebaceous glands and produce acne. It disappears spontaneously within 3 to 6 months.
