Related Experiment Video
Updated: May 15, 2026

Minimal Erythema Dose (MED) Testing
Published on: May 28, 2013
A 9-year-old boy with a hyper-pigmented patch on the right chest
Benjamin Bohaty1, Sarah L Chamlin
1Department of Dermatology, Northwestern University Feinberg School of Medicine, USA.
Abstract:
CME EDUCATIONAL OBJECTIVES: 1.Understand the clinical presentation of a Becker nevus.2.Describe the differential diagnosis for Becker nevus.3.Be able to discuss the appropriate management for a Becker nevus. A 9-year-old healthy male presented to the dermatology clinic for evaluation of lesions on his chest. The lesions were unilateral and had been present for at least 1 year. No lesion had been previously noted in the affected area. No treatments had been tried prior to presentation. The patient denied pruritus or pain. Review of systems, medical history, and family history were unremarkable.
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