Vitiligo clinical features and treatment
Vitiligo Â is an acquired disorder in whichmelanocytes are lost from the basal layer of the epidermis.It occurs in about 0.4% of the population. A genetic basisis likely, as about 40% have a family history. In the individualsand their families there is an increased frequencyof organ-specific autoimmune diseases, e.g. hypo- andhyperthyroidism. The precise pathogenesis is unknown
.Clinical features Vitiligo has often begun by the age of 20. It is characterizedby sharply defined areas of pigment loss, sometimeswith mild hyperpigmentation of the adjacent normal skin. The texture is normal and there is no scaling. In paleskinnedindividuals their first awareness may be sunburnin the depigmented skin. Any site can be affected andsymmetrical involvement is common. Occasionally vitiligoÂ follows a dermatomal pattern. The face, axillae, groins,backs of hands, knees and elbows, and the genitalia are common sites. The condition is usually progressive, but repigmentation can occur spontaneously.
Diagnosis Diagnosis is usually straightforward. By Wood's light Â pityriasis versicolor (which is scaly) fluoresces yellow,and vitiligo is more strikingly white than the other causes of hypopigmentation. The pale macules of leprosy are hypoanaesthetic.
Treatment No treatment is entirely satisfactory. Cosmetic camouflageis helpful in a few. Sunscreens should be used on exposedareas to prevent burning and chronic sun damage, and inthe pale-skinned this measure can improve the appearance by reducing tanning of the surrounding normal skin. Othermeasures used include psoralens and UVA Â and the short-term applicationof potent topical corticosteroids.
note In the individualsand their families there is an increased frequencyof organ-specific autoimmune diseases, e.g. hypo- andhyperthyroidism. The precise pathogenesis is unknown.