Glen is a 48-year-old IT professional who presents with a two-week history of painless scaly erythematous plaques on the lower back.

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Glen is a 48-year-old IT professional who presents with a two-week history of painless scaly erythematous plaques on the lower back (pictured). He has psoriasis, which has been stable on monthly subcutaneous secukinumab 300mg for several years.

Glen was treated with antivirals for shingles in the same distribution one month ago. The blisters dried and crusted off over 10 days, and two days later, red lesions with white scale developed, overlying the healing zoster lesions. He has no associated neuralgia.