vitiligo is an acquired depigmenting disorder in which melanocytes are destroyed, resulting in irregularly shaped white patches on the skin
may also affect hair (patches of grey hair leukotrichia) and the retina
affects 0.5-1% of population and all races
pigment loss begins before 20yrs age in 50%
new-onset vitiligo sometimes follows physical injury to the skin, such as sunburn, or emotional stress
20% have a family history
some have underlying
immunoglobulin deficiency with associated auto-immune disorders and risk of recurrent infections or allergies
white patches may be more readily seen with a Wood's lamp
vitiliginous skin is at high risk of UV damage and thus needs to be protected from the sun