Board Review: Syphilis

Case 1: A 35-year-old man with no past medical history presents with a painless ulcer in his right groin following a reported unprotected sexual encounter one week prior with a new partner. The patient reported a history of treated syphilis five years ago. FTA Ab is positive, and RPR is negative. What is your diagnostic approach?

Case 2: A 20-year-old man with past medical history HIV, well controlled on B/F/TAF, presents with a rash on palms and soles of hands and feet, fevers, and generalized fatigue for three days. RPR is negative. FTA ab is positive. The patient denies any known history of syphilis. What is your diagnostic approach?

Case 3: A 28-year-old woman who is 13 weeks pregnant, asymptomatic, presents with positive FTA-Ab, RPR 1:2. She is penicillin allergic. She reports that the penicillin reaction was hives ten years ago. She had a history of syphilis five years ago and was treated with 14 days of doxycycline. RPR initial titer was 1:64, and her last known titer was 1:1 three years ago. What is your next diagnostic approach?

Case 4: An 85-year-old woman with past medical history of diabetes, hypertension, coronary artery disease is referred to you after workup for acute worsening mental status over the past year. Laboratory testing reveals positive FTA-Ab and RPR 1:1. She does not recall ever being treated for syphilis in the past, but she is confused and unable to provide an adequate history. What is your diagnostic approach?

Case 4, Part 2: Lumbar puncture shows 2 WBCs, normal glucose, protein 68, and negative CSF VDRL negative. What is the next diagnostic step?

Case 5: A 28-year-old man with past medical history of newly diagnosed HIV, recently started on DTG/TDF/FTC, presents with secondary syphilis and RPR titer of 1:32. He is treated with one dose of Benzathine PCN 2.4 million units. Six months later, he comes for a follow-up, and the RPR titer is now 1:128. The patient is adamant that he was not reexposed and has not had any sexual encounters since he was last treated for syphilis. His only complaint at the follow-up visit was a headache. Denies any fevers, rash, hearing, or visual changes. What is your diagnostic approach?

Case 6: A 45-year-old man with past medical history of newly diagnosed HIV, recently started on B/F/TAF five weeks ago, presents to the office with fevers, rash, headache, and intermittent blurry vision with associated floaters in his left eye for the past two days. His baseline RPR was negative one month ago. He has been compliant with his ARV. His CD4 count is 458, and his HIV viral load is now undetectable. Physical exam is notable for temperature of 100.8, diffuse maculopapular rash on the palms of his hands and the soles of his feet. He has reduced visual acuity in the L eye. His alkaline phosphatase is elevated at 350. FTA-Ab is positive and RPR is 1:256. Ophthalmology is consulted and left-sided posterior uveitis is reported. Lumbar puncture shows 4 WBCs, protein is normal, and CSF VDRL is negative. How do you approach treatment in this patient?