• A chronic, systemic infectious disease caused by the spirochete Treponema pallidum
  • Transmitted sexually by direct contact with an active lesion; also transmitted vertically (maternal–fetal) and via blood transfusions
  • Untreated disease includes four overlapping stages.
    • Primary: single (usually) painless chancre at point of entry; appears in 10 to 90 days; chancre heals without treatment in 3 to 6 weeks.
    • Secondary: appears 2 to 8 weeks after primary chancre; nonpruritic rash on palms or soles of feet, mucous membrane lesions, headache, fever, lymphadenopathy, and alopecia
    • Latent: seroreactive without evidence of disease
      • Early latent: acquired within the last year
      • Late latent: exposure >12 months prior to diagnosis
    • Tertiary (late): Serology may be negative (fluorescent treponemal antibody absorption [FTA-ABS] test typically positive).
      • Gumma, cardiovascular, and late neurosyphilis; may be fatal
    • Neurosyphilis: any type of CNS involvement; can occur at any stage
      • Psychosis, delirium, dementia

Pediatric Considerations
In noncongenital cases, consider child abuse.

Pregnancy Considerations

  • Screen all patients who are pregnant with venereal disease research laboratory (VDRL) test or rapid plasma reagin (RPR) test early in pregnancy, (i.e., first prenatal visit); if high risk, repeat at 28 weeks and at delivery (1)[A].
  • Use the same nontreponemal test for initial screening and for follow-up (1)[A].



  • Syphilis rates decreased through 2000 and have since increased (primarily in men who have sex with men [MSM]) (2).
    • All stages: 53 per 100,000
  • Congenital: 78/100,000 live births (2)


  • Predominant sex for primary and secondary syphilis: male (78%) > female (22%) (2)
  • Highest prevalence in MSM (2)

Etiology and Pathophysiology

T. pallidum enters through intact mucous membranes or breaks in skin. The organism quickly enters the lymphatics to cause systemic disease; highly infectious; exposure to as few as 60 spirochetes is associated with ~50% chance of infection.

Risk Factors

MSM, multiple sexual partners, exposure to infected body fluids, injection drug use, transplacental transmission, adult individuals in custody, high-risk sexual behavior, people living with HIV (PLWH)

General Prevention

Education regarding safe sex; condoms reduce but do not eliminate transmission (1)[A].

Commonly Associated Conditions

HIV infection, hepatitis B, and other sexually transmitted infections (STIs)

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