Clinical and dermoscopic analysis of 32 cases of acquired facial hyperpigmented macules

Background: Acquired facial hyperpigmented macules (AFHM), which appear as non-segmental pigmented macules without a history of obvious localized inflammation, usually occur on the foreheads and temples of young children. Currently, the etiology and pathogenesis of AFHM remain unclear. Objective: To investigate the clinical and dermoscopic features of AFHM. Methods: A retrospective study was conducted on the clinical and dermoscopic features of 32 children with AFHM. Results: The lesions of AFHM are light brown macules ranging in size from millet to peanut, without any symptoms, mainly distributed on the foreheads and temples. Light brown pseudoreticular pigment and linear/branching vessels are the two major dermoscopic features of AFHM. During the follow-up period, which ranged from 31 months to 67 months, the lesions of all patients improved, and 27 of the 28 followed patients (96.4%) showed complete disappearance of the lesions. Conclusion: Acquired facial hyperpigmented macules is a self-limited disease characterized by sudden appearance of irregularly shaped pigmented macules on the foreheads and temples in young children. We propose a hypothesis that ultraviolet radiation may play an important role in the etiology and pathogenesis of AFHM.