Syphilis

Pathogen

  • Treponema pallidum (spirochaete)

Epidemiology

  • Approx 6 million new cases /year (2018)

  • Sexual contact (with sore, rash in second stage), MTCT

  • Higher in FSW/MSM

Clinical

  • Incubation 9-90 days

Primary

  • Local infection, painless ulcer (chancre): heals without treatment 2-6 weeks

Secondary

  • Dissemination, systemic illness (fever, malaise, LN, meningitis...) & rash (trunk, palms, soles, many forms, papules: condylomata lata)

Latent period

  • Early (first 4 years after contact)

  • Late

Tertiary

  • Skin/mucosa/bone: gumma (painless punched out ulcer), periostitis

  • Cardiac: aortic aneurysm, coronary artery stenosis

  • Nervous system: general paresis, tabes dorsalis (spinal cord degeneration)

Diagnosis

  • Visual bacteria: dark field microscopy of fresh tissue fluid

  • Nucleic acid detection

  • Antibody detection/serology: main method

    • Screen for active disease with sensitive non-treponemal test e.g. Rapid Plasma Reagin (RPR) or VDRL

    • Confirm with specific treponemal (T.pallidum antigen) test e.g. THPA, TPPA or FTA (stay positive for life)

Management

  • Penicillin (benzathine)

Pregnancy

  • Penicillin stat dose (also treat infant if >28/40)

Prevention

  • Screen in pregnancy