In vitiligo, what notable appearance do the lesions exhibit under Wood's lamp examination?

In vitiligo, the lesions exhibit a milk-white fluorescence under Wood's lamp examination. This phenomenon occurs because the skin affected by vitiligo lacks melanin, which is the pigment responsible for normal skin coloration. When illuminated by the Wood's lamp, the absence of melanin in the lesions causes them to appear bright white, effectively highlighting the contrasts between the affected and unaffected skin.

The milk-white fluorescence is indicative of the condition and helps dermatologists differentiate vitiligo from other similar skin disorders that may not show the same intensity or coloration under this light. This examination tool is invaluable in clinical practice for accurately assessing the extent of depigmentation in vitiligo patients.