Syphilitic Leukoplakia

A 28-year-old male was referred by his primary care physician for workup of possible oral candidiasis. He had been diagnosed with asymptomatic HIV-infection 18 months earlier and had undetectable viral load under antiretroviral treatment. The patient reported a history of multiple unprotected sexual encounters over the preceding 3 months. Physical examination showed painless and confluent whitish mucous patches (about 2 cm long) with erythematous border on the left soft palate which did not scrape off with a tongue depressor (Panel A). A biopsy specimen from the damaged mucosa was obtained and revealed hyperplasia of the epithelium and a dense inflammatory infiltrate in the corion, composed mainly by plasma cells (Panel B and C). Immunohistochemistry highlights numerous treponemal spirochetes, brown chromogen (Panel D and E). Treponemal tests (EIA and TPPA) were reactive and Rapid Plasma Reagin test (RPR) was positive (titer, 1:32). A diagnosis of syphilis was made. The patient was initially treated with intramuscular penicillin G benzathine. At 3-month follow-up he had complete resolution of palate lesion.