Quiz Ref IDVitiligo is a relatively common, acquired pigmentary
disorder characterized by areas of depigmented skin resulting from loss of
epidermal melanocytes. The prevalence of this disease varies from 0.1% to
2% in various global populations. Onset may occur at any age, but the incidence
usually peaks in the second and third decades of life. Patterns of distribution
of the disease include the generalized, acral or acrofacial, localized, and
segmental types. The generalized distribution is the most common pattern and
is characterized by symmetrically distributed areas of depigmentation. Segmental
vitiligo is the least common pattern and occurs in a dermatomal or quasi-dermatomal
distribution, often following the distribution of the trigeminal nerve. The
course of the disease is unpredictable. Vitiliginous skin lesions may remain
stable or slowly progress for years. In some instances, however, patients
undergo rapid, complete depigmentation in 1 or 2 years.