<prompt> A young man presents to the emergency depament with a maculopapular rash 2 weeks after healing of a painless genital ulcer. The most likely etiological agent isTreponemapallidumTreponemapeunaeChalmydia TrachomatisCalymatobacter granulomatis  <response>: A i.e. Treponema pallidum Development of nonpruritic maculopapular rash secondary syphilis two weeks after heeling of painless genital ulcer primary syphilis suggest Treponema pailidium as an etiological aget. 