Ultraviolet light-induced leukoderma of the scalp associated with androgenetic alopecia: senescent actinic depigmentation of the scalp.

BACKGROUND

Human scalp skin is normally protected from sunlight and ultraviolet radiation by the presence of hair. When hair loss occurs, for example, in androgenetic alopecia, this protective factor declines.

OBJECTIVE

We report a series of 10 type IV and V skin patients with a male predominance (60-85 years). All patients suffered from androgenetic alopecia starting from the age of around 40 to 45 years. They all noticed asymptomatic, well-defined, depigmented macules, which were seen only in areas that have been afflicted by androgenetic alopecia. The depigmented macules remain within the confines of the hair margin. There has been no depigmented lesion elsewhere on the body. The patients did not report any association with any drug that they may have started taking. There is no history of vitiligo in these patients or their families. Biopsy samples taken from three of the patients showed solar elastosis.

CONCLUSIONS

The entity of ultraviolet-induced scalp leukoderma and androgenetic alopecia has not been acknowledged in dermatology textbooks but needs consideration for its importance in differential diagnoses. The term senescent actinic depigmentation of the scalp is suggested.