¡¡1. Diagnosis
The diagnosis of vitiligo is not difficult. There is no
significant difference in the incidence of the disease
in men and women, and it may occur in newborns or in old
persons. However, persons in the age of 6-25 years have
the highest incidence. The disease starts as one or several
hypopigmented spots or patches. Because of incomplete
loss of melanin initially, the color of the lesions are
pale white and the margins are not clear-cut between the
lesion and the normal surrounding skin. As the lesions
gradually develop, there is complete loss of melanin and
the demarcation with the normal skin becomes clear and
the color of the lesions are ivory or porcelain white.
The lesions may be of different shapes such as round,
oval or geographical. The number of lesions varies, from
single to multiple, and the sizes may vary. Any part of
the body can be involved. The site of predilection in
descending order is: the face, neck, head, abdomen, hips,
hands and feet, four limbs, chest and back, external genitalia,
peri-anal area, peri-oral area, the glans and prepuce,
and mucous membrane.
2. Differential diagnosis
(1) Tinea versicolor: Tinea versicolor is a hypopigmentary
skin disease caused by fungus. The site of predilection
is the back, chest, neck, and upper limbs. The margins
of the skin lesions are blurred and scales can be seen
with gentle scratching. This disease may be confused
with early stage vitiligo when there is incomplete loss
of pigment. The key points for differentiation are that
there are no scales in vitiligo and upon pressure the
margin of the lesion becomes clear in vitiligo but unclear
in tinea versicolor.
(2) Senile leukoderma: The disease is seen in middle-aged
individuals and most common in older people. They are
round, grain to bean-sized white spots with slight central
depression. They are scattered over the surface of the
body and do not coalesce to form large patches. The
lesions commonly occur on the chest, back and four limbs
but not on the face. It is not seen in children and
adolescents.
(3) Nevus anemicus: The main characteristic of the disease
is that it is present at birth. There are hypopigmented
rather than depigmented patches and margins are blurred.
The lesions are pale white patches mostly restricted
to certain areas of the body without dissemination or
extension in the majority of the patients. But as the
body develops the lesions may be increased in size.
Clinically about 15 % of the patients with nevus anemicus
may be complicated with vitiligo in other parts of the
body with the possibility of further progression. Therefore,
the disease should also be treated.
(4) Pityriasis alba: This disease is commonly seen in
children with hypopigmented patches on the face. The
color of the patch is pale white, and the surface is
dry with fine grayish-white scales. The margin of the
lesion is poorly circumscribed. The white patches of
vitiligo are sharply demarcated and no scales are found.
(5) Piebaldism: This is a congenital skin disease. The
most characteristic feature is a triangular or diamond-shaped
white macule in the midline of the forehead, usually
with a white forelock. Piebaldism is usually seen with
other changes such as heterochromic irides, deafness,
mental retardation, harelip, ear and tooth malformations.
(6) Albinism: It is a congenital disease, with positive
family history often for generations. It is caused by
the decrease or absence of pigment in the skin hair
and the eyes. Hair in such patients are pure white,
silvery white, pale white, yellow white, blond, and
even red. The hair is thin and glossy. Vitiligo is an
acquired disorder, the white patches of white are usually
surrounded by a hyperpigmented border. The number of
the patches may change or disappear in the course of
the disease.
3. Clinical classification
of vitiligo
There are different classifications for vitiligo in
different parts of the world. Based on the 1994 classification
(draft) by the Pigmentary Skin Disease Group of the
Chinese Association of Combined Traditional Chinese
and Western Medicines, vitiligo is classified as 2 types,
2 kinds and 2 stages.
(1) Two types: Common and segmental types
1) The common type is subdivided into localized, scattered,
disseminated and acral types.
¢Ù Localized type: a single or a small group of white
patches of different sizes, mainly restricted to a particular
part of the body;
¢Ú Generalized type: multiple white patches scattered
over large areas of the body, but the total area of
vitiligo is less than 50 % of the body surface area;
¢Û Universal type: the involvement is larger than 50
% of the total body surface area, mainly as a result
of prolonged illness;
¢Ü Acral type: the white patches are mainly found on
the hands and feet as well as the fingers and on the
scalp and face.
2) Segmental type: the white patches are dermatomal
or quasi-dermatomal in
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