Biett Sign as an Indicator of Secondary Syphilis
A man in his early 70s presented with a 5-day history of palmoplantar rashes. He reported no constitutional symptoms but a history of unprotected intercourse 3 months prior. Upon examination, there were multiple erythematous macules with annular collarettes of scales on the palms (Figure A) and soles (Figure B), consistent with Biett sign. Laboratory assessments revealed positive rapid plasma reagin and Treponema pallidum particle agglutination tests with titers of 1:256 and 1:1280, respectively, leading to a diagnosis of secondary syphilis.