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Written by Professor James Ferguson, consultant dermatologist
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What is vitiligo?
This condition is an important cause of depigmentation (loss of
colour) of the skin. It affects all races but is most obvious in people with
darker skins.
It affects approximately 1 person in every 200 of the
population. Around 40 per cent of patients have an affected family member.
What causes vitiligo?
Healthy skin contains melanin, a brown pigment produced from the
amino acid tyrosine by pigment cells (melanocytes) in the skin.
If skin affected by vitiligo is examined under a microscope,
the melanocytes are absent and there are signs of inflammation in the deeper
layer of the skin.
It is not known exactly why some people develop this condition
and others do not. Some experts believe it is an autoimmune disorder (in which
an individual's immune system reacts against part of their own body).
In vitiligo, specific autoantibodies against a patient's
melanocytes are found in the blood, although it is not known whether
autoantibodies are the cause or an effect of the damage seen. There are many
autoimmune disorders and some families are more prone to this group of
conditions as a whole.
Another explanation for vitiligo suggests it is due to a nerve
disorder, because nerve damage has been associated with pigment loss in the
area of skin served by the nerve.
Vitiligo is equally common in men and women. It can appear at
any age but 50 per cent of patients are under 20 when it first appears.
Symptoms involve the physical appearance as well as its psychological
impact.
Physical appearance
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In childhood, vitiligo frequently appears as 'halo
naevi', in which areas of depigmentation surround small, pigmented naevi.
(A naevus is any clearly defined skin abnormality present at birth.)
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The areas of depigmentation are usually seen first on skin
that is exposed to light, particularly the face or back of the
hands.
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Initially the pigment loss is often patchy, with areas of
partial loss close to areas with complete absence of melanin.
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Often it is symmetrical with both halves of the body equally
affected, but occasionally only one segment of skin will be involved (so-called
segmental vitiligo).
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Some sufferers will have the Koebner phenomenon, in which skin
changes occur at the site of skin trauma. In this situation, vitiligo can
develop at the site of abrasions, surgical scars and even
eczema or
psoriasis.
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The hairs in areas of vitiligo either remain pigmented or can
go white (leukotrichia). Occasionally premature greying of hair can occur not
only in vitiligo patients but also in their relatives.
Psychological impact
This varies greatly from person to person, depending on their
condition, their social and occupational situation and their psychological
wellbeing.
Vitiligo is often most obvious in darkly pigmented individuals,
in whom the disease can have profound psychological consequences. These effects
ranges from mild embarrassment to a severe loss of self-confidence and social
anxiety, especially for those who have lesions on exposed skin.
Can vitiligo be a sign of serious disease?
Malignant melanoma (cancer of the melanocyte) can develop
simultaneously with vitiligo. However, the vast majority of patients with
vitiligo do not have this cancer, which tends to occur at a later age.
Patients have an increased chance of developing any of the
autoimmune diseases, which include Addison's disease, thyroid problems
(hyperthyroidism and
hypothyroidism),
diabetes and alopecia
areata (patchy hair loss).
What is the treatment?
Patients need to use strong sunscreens to prevent sunburn of
severely affected skin. Several treatments exist that aim to hide or reverse
depigmentation, or prevent further pigment loss from occurring. None are
universally successful and all have limitations.
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Camouflage: the depigmented areas can be
covered with makeup or topical dyes that are applied to the skin. Specific
advice can be obtained from a camouflage clinic (see 'Support groups and
relevant organisations below).
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Photochemotherapy has been used extensively
for vitiligo. This treatment combines a light-activated drug (psoralen) with
ultraviolet A (UVA) irradiation (hence it is called PUVA). PUVA is rarely
completely successful and often requires many treatments over months, which is
a considerable commitment for the patient. Studies show PUVA offers only a
slight advantage over placebo (dummy treatment).
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Corticosteroids, both topical (applied to the
skin) and systemic (as tablets or by injection) are used for vitiligo. While
there is no doubt that the degree of improvement is greater than one would
expect with placebo therapy, less than 50 per cent of patients respond to this
treatment.
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Skin grafting: in dark-skinned patients, skin
grafting of pigmented skin samples from another body site can stimulate
repigmentation.
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Depigmentation: where depigmentation has been
extensive, a monobenzyl ether of hydroquinone can be used as a cream to remove
remaining areas of pigment. This treatment is usually a last resort, but
occasionally it is the best approach for a patient.
What is the outlook?
Vitiligo usually slowly progresses, often in fits and starts -
ie it will extend rapidly over a short period of months and then show little
change over subsequent years.
Treatment is generally unsatisfactory - long-term PUVA will help
a proportion of patients. Small skin grafts or potent topical steroid
preparations occasionally help cosmetically disabled patients.
Support groups and relevant organisations
British Association of Skin Camouflage, c/o Resources For
Business, South Park Road, Macclesfield, Cheshire SK11 6FP. Telephone: 01625
267880. Website: www.skin-camouflage.net.
Disfigurement Guidance Centre, PO Box 7, Cupar, Fife KY15 4PF.
Telephone: 01337 870281.
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Last updated 01.08.2005
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