Vitiligo
is a
pigmentation disorder in the human
skin. The human skin contains special skin cells (melanocytes) that
produce the pigment melanin which colors the skin.
In Vitiligo, the special skin cells (melanocytes)
as well as the tissues (mucous membranes) that line the inside of the
mouth, nose, genital and rectal areas, and the retina of the eyes are
destroyed. As a result, white patches of skin appear on different parts
of the body. The hair may also turn white that grows in areas affected
by vitiligo. What causes vitiligo?
There are several theories regarding the cause of
vitiligo but the actual cause is not fully known. According to one
theory, people with vitiligo develop antibodies that, turn upon them
and destroy their own melanocytes instead of protecting them. There is
another theory according to which the melanocytes somehow attack and
destroy themselves. Finally, some people with vitiligo have reported
that a single event such as severe sunburn or an episode of emotional
distress is the main cause of this order. Scientifically, events of
this nature have not been accepted as the main cause of vitiligo. These
are merely coincidences.
Who is affected
by vitiligo?
The number of people affected by vitiligo
(http://www.antivitiligo.com/vitiligo.html ) disorder ranges from 40-50
million. It forms about 1 to 2% of people in the world. 2 to 5 million
people have the disorder in the United States alone.
Vitiligo affects all races and both sexes equally
and ninety-five percent of its victims are below the age of 40.
What is the
association of vitiligo with autoimmune disease?
In Autoimmune diseases, a person's immune system
reacts against the body's own organs or tissues. Vitiligo is found to
be more common in people with certain autoimmune diseases.
Autoimmune diseases that are associated with
vitiligo include: hyperthyroidism (over activity of the thyroid gland),
adrenocortical insufficiency (the adrenal gland does not produce enough
of the hormone corticosteroid), alopecia areata (patches of baldness),
and pernicious anemia (a low level of red blood cells caused by the
failure of the body to absorb vitamin B12).
Is vitiligo
inherited?
Vitiligo may be hereditary in some cases. Children
of vitiligo affected parents are more likely to develop vitiligo
disorder. However, most children will not get vitiligo even if a parent
has it. Also most people with vitiligo do not have a family history of
the disorder.
Large number of inherited disorders are associated
with vitiligo. They include: albinism of the ocular type, autoimmune
polyendocrinopathy syndrome, congenital deafness with vitiligo and
achalasia, dyschromatosis symmetrica hereditaria, ermine phenotype,
familial histiocyctic reticulosis, kabuki syndrome, and the syndrome of
spastic paraparesis, vitiligo, premature graying and characteristic
facies.
The abundance of genetic diseases associated with
vitiligo clearly proves that there are a number of genes which normally
govern the development and wellbeing of the melanocytes.
What are the
symptoms of vitiligo?
White patches (depigmentation) on the skin are the
foremost symbol of vitiligo. These patches are more common in
sun-exposed areas, including the hands, feet, arms, face, and lips.
Other common areas are the armpits and groin, and around the mouth,
eyes, nostrils, navel, and genitals.
Vitiligo generally appears in one of three
patterns: focal pattern, segmental pattern and generalized pattern. In
focal pattern, the depigmentation is limited to one or only a few
areas. In segmental pattern, depigmented patches are developed on only
one side of the body. But in the generalized pattern, depigmentation
occurs on different parts of the body.