Contact leukoderma of the scalp or an unusual variant of vitiligo?

Contact leukoderma due to hair dyes is strongly suspected in patients presenting with depigmented patches sharply localized to the scalp. We describe three patients with a striking pattern of depigmentation, which stopped abruptly at the hair margins. However, no definite correlation with the use of hair dyes could be made in any of them. Our cases represent an unusual pattern of vitiligo of the scalp, which seems to have been previously attributed mainly to hair colorants. Careful examination of the lesions on the scalp may reveal more cases with this pattern.