Overview
Definition
A chronic, systemic sexually transmitted infection caused by a spirochete.
Epidemiology
Incidence is increasing, particularly among men who have sex with men (MSM).
Etiology & Risk Factors
- Treponema pallidum (a spirochete). Transmitted via direct contact with an infectious lesion during sex, or vertically (congenital syphilis).
Clinical Symptoms
- Primary: Painless chancre (ulcer) at the site of inoculation, often accompanied by non-tender regional lymphadenopathy
- Secondary (Weeks/Months later): Disseminated maculopapular rash (classically involving the PALMS and SOLES), Condylomata lata (highly infectious, wart-like lesions on genitals), patchy alopecia
- Tertiary (Years later): Gummas (granulomatous lesions), Aortitis (ascending aortic aneurysm), Neurosyphilis (Tabes dorsalis, Argyll Robertson pupils - accommodate but do not react to light)
Clinical Approach
Diagnosis
- Nontreponemal tests (Screening): VDRL or RPR (measure antibodies against cardiolipin, can be falsely positive)
- Treponemal tests (Confirmatory): FTA-ABS or TP-PA (detect specific antibodies against T. pallidum, remain positive for life)
Management
- Primary, Secondary, or Early Latent: Single dose of IM Benzathine Penicillin G
- Late Latent or Tertiary: Weekly IM Benzathine Penicillin G for 3 weeks
- Neurosyphilis: IV Aqueous Penicillin G for 10-14 days
- Note: If a pregnant patient has syphilis and a penicillin allergy, she MUST be desensitized and treated with Penicillin.
Complications
- Irreversible neurological damage (Tertiary)
- Cardiovascular collapse (Aortic aneurysm rupture)
- Severe congenital defects if untreated in pregnancy