You are correct. The lesions are typical of annular secondary syphilis (annular, arcuate, or gyrate patterns w/ delicate, slightly raised, infiltrated, or scaling ridges), and a positive rapid plasma reagin test confirmed it. During the course of untreated secondary syphilis, annular lesions may appear and disappear; when they reappear, the lesions are usually larger, darker, and more discrete. A generalized nonpruritic maculopapular rash is more common than an annular rash in secondary syphilis. Pt was treated w/ IM penicillin G benzathine, and the lesions resolved after 3wk, w/ only slight hyperpigmentation visible.

BMJ 2019;367:l5512