you may need to know about
Acne
A rash, usually on the face, due to blockage and inflammation
of glands in the skin.
There are various types of acne. The most common form is
acne vulgaris, which is the familiar rash that affects many
teenagers. Acne vulgaris is more common and tends to be more
severe in males. The condition is triggered by hormonal changes
at puberty and may appear as early as the age of 10. The rash
usually subsides after adolescence but may persist after the
age of 30. Acne can cause great psychological distress, and
teenagers may feel especially self-conscious about their appearance.
More unusual forms of acne include occupational acne, which
results from exposure to certain types of industrial oil,
and drug-induced acne, which is caused by some prescribed
drugs, such as corticosteroids.
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Formation of acne lesions
Acne develops when excess sebum, and in some cases the
protein keratin, blocks hair follicles. Bacteria multiply
in the trapped sebum, infecting the surrounding tissues
and causing various types of lesion.
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What are the causes?
Acne vulgaris is caused by the overproduction of sebum, an
oily substance secreted by the sebaceous glands in the skin.
Normally, the sebum drains into hair follicles and flows out
through the follicle openings on the skin's surface, thereby
keeping the skin lubricated and supple. However, when the
glands produce excess sebum, the follicles become blocked.
If the sebum remains clogged in the follicle openings, it
hardens and becomes dark, forming plugs called blackheads.
In some cases, follicles are sealed by an excess of keratin,
the tough, fibrous protein produced by the skin cells. When
this happens, the trapped sebum hardens into white lumps,
called whiteheads, under the surface of the skin. In both
types of blockage, bacteria multiply in the sebum, causing
inflammation of the surrounding tissues.
Acne starting at puberty is thought to result from increased
sensitivity to androgens (male sex hormones), which are present
in both boys and girls and levels of which are raised during
puberty. Androgens cause the sebaceous glands to increase
their output of sebum. There may be a genetic factor since
acne can run in families. The use of anabolic steroids to
improve performance in sports may also raise androgen levels.
Other causes of acne vulgaris include hormonal disorders such
as Cushing's syndrome, which is due to an excess of corticosteroid
hormones.
Acne may become worse in times of stress. In girls, outbreaks
may be affected by the hormonal fluctuations that occur during
the menstrual cycle. The condition may also be exacerbated
by the use of oil-based cosmetics.
Poor hygiene does not cause acne, although a build-up of
oil and dead cells on the skin surface may increase the risk
of blocked follicles and allow bacteria to multiply. There
is no evidence that fatty foods, sweets, or chocolate either
cause or aggravate acne.
Occupational acne is usually caused by long-term contact
between the skin and oily clothes. The reasons for drug-induced
acne are not known.
What are the symptoms?
Acne vulgaris occurs in areas of skin that have a high density
of sebaceous glands. At puberty, the hair, face, and upper
trunk normally become greasy due to increased production of
sebum. However, in people with acne, oiliness is excessive.
Acne tends to appear on the face, but other areas such as
the upper back, centre of the chest, shoulders, and neck are
also commonly affected. The disorder is usually more severe
in winter and tends to improve in summer with increased exposure
to sunlight. Lesions that are caused by occupational acne
may appear on parts of the body that come into close contact
with oily clothes, such as the thighs. All forms of acne may
produce some or all of the following types of lesion:
Tiny blackheads.
Small, firm whiteheads.
Red pimples, often with yellow pus-filled tips.
Painful, large, firm, red lumps.
Tender lumps beneath the skin without obvious heads (cysts).
All of the types of lesion listed above may develop at any
one time, but the severity of acne varies greatly from person
to person. Deep-seated lesions may leave scars after they
have healed.
What is the treatment?
Self-help measures may help to clear up mild acne and prevent
recurrence. Your doctor may also recommend a topical drug
treatment, such as benzoyl peroxide or retinoid cream to loosen
keratin that is sealing the hair follicles. The doctor may
also prescribe topical antibiotics. Moderate acne is often
successfully treated with a low-dose oral antibiotic, such
as tetracycline or erythromycin.
If these treatments fail, you may be referred to a dermatologist.
He or she may prescribe isotretinoin, an oral retinoid that
acts to loosen keratin and reduce sebum secretion. However,
the use of isotretinoin during pregnancy is known to result
in fetal abnormalities. For this reason, sexually active women
should take the drug only if they are using a reliable contraceptive.
Some women may be prescribed the combined pill, which may
relieve acne by counteracting the action of androgens.
There is no immediate cure for acne. However, scarring may
be prevented if treatment is started at an early stage. Individual
acne cysts may be treated with corticosteroid injections.
If acne has already left noticeable scars, you may wish to
consult a cosmetic surgeon and discuss techniques such as
dermabrasion. In this procedure, the top layer of skin is
removed under a general anaesthetic. The raw areas then heal
to leave a more even layer of skin.
Self-help: controlling acne
Following these simple self-help measures may help clear
up acne and prevent further episodes:
Wash your skin twice a day with warm, but not hot, water
and a mild cleanser. Do not scrub your skin too vigorously.
Do not pick at pimples because this may make the condition
worse and result in scarring.
Apply a benzoyl peroxide cream daily to the affected areas.
If you have occupational acne, keep work clothes clean to
avoid prolonged contact with oils.
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