Back to Basics: Syphilis

Back to Basics: Syphilis

By: Danielle Kovalsky, MD


Primary Syphilis:

  • Typically presents around 21 days after exposure
  • Presents with a chancre: PAINLESS ulcer with induration that can present on any area of sexual contact (including the oral mucosa).  Typically lasts 3-6 weeks and resolves spontaneously.  Can present with regional lymphadenopathy.  No constitutional symptoms.  Some patients never present with chancre.

Secondary Syphilis:

  • Typically presents 3-6 weeks following the end of the primary stage
  • Classic rash: red-pink, papular, does not spare the palms and the soles
  • Lymphadenopathy
  • Alopecia: described as “moth eaten” due to patchy appearance
  • Non-specific symptoms: fever, sore throat, headache
  • Ocular findings: most common = uveitis

Tertiary Syphilis:

  • Typically presents 3-20 years after initial infection
  • Nervous system manifestations: meningitis, dementia, neuropathy, tabes dorsalis
  • Cardiovascular system manifestations: thoracic aortic aneurysms, aortic valve regurgitation
  • Gummatas: rare, granulomatous lesions that can present anywhere in the body (i.e. skin, bones, internal organs)

There has been a rise in cases of syphilis in the U.S.

  • From 2.1/100,000 in 2001 to 10.8/100,000 in 2018 (CDC)
  • Higher rise in MSM and women

Who should be tested for syphilis?

  • Symptomatic patients
  • Asymptomatic patients with a partner diagnosed with syphilis (treat empirically), sexually active men who have sex with men (MSM), HIV-infected individuals, or any patient with high risk sexual behavior
    • "High risk” behavior includes previous diagnosis of STI, people who exchange sex for money or drugs, indvididuals with multiple partners not using condoms


  • Nontreponemal tests: Venereal Disease Research Laboratory test (VDRL) and Rapid Plasma Reagin (RPR)
    • Detect nonspecific antibodies to cardiolipins that are released as a result of infections
    • Screening tests
    • Can also be used to assess disease activity and response to treatment
    • Will likely not be positive until 1-4 weeks post-chancre
  • Treponemal Antibody test:
    • Fluorescent Treponemal Antibody Absorption Test (FTA-ABS)
    • Specific test
    • Will be reactive for life regardless of disease activity or treatment
    • Typically used as a confirmatory test, however, cheaper costs increasing use as screening test


  • Primary/Secondary Syphilis
    • 2.4 million units IM Penicillin G benzathine in a single dose
    • Penicillin allergy? Doxycycline BID for 2 weeks or ceftriaxone 1-2 g IM/IV 10-14 days
    • Penicillin allergy and pregnant? Require penicillin desensitization
  • Tertiary Syphilis
    • 2.4 million units IM Penicillin G weekly for 3 weeks
    • Repeat testing at 6 and 12 months
  • Jarisch-Herxheimer reaction: acute febrile reaction that presents with myalgias and headache within 24 hours of treatment of syphilis. It is self-limited and can be treated with NSAIDs. Warn your patients!



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