American Urological Association - Syphilis


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Image A

Image B

  • Agent: Treponema pallidum - "the great mimicker".
  • Appearance: gram-negative spirochete.
  • Clinical: 3 stages:
    • Primary: papule on the penis → ulcerated painless chancre; resolves without treatment in 6-8 weeks (image A).
    • Secondary: maculopapular, annular, or hyperpigmented lesions, especially on palms and soles.
    • Tertiary: granulomas (gummas) that may involve the CNS.
  • Histology:
    • Primary: dark-field microscopy or special stain reveals spirochetes (image B); lymphoplasmacytic vasculitis; antibody test is negative.
    • Secondary: organisms may or may not be seen; lymphoplasmacytic inflammation; antibody test is positive.
    • Tertiary: small compact granulomas that eventually caseate.
  • Treatment: antibiotics.