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Syphilis Basics - The Great Mimic

  • Agent: Treponema pallidum, a thin, motile spirochete.
  • Visualized: Dark-field microscopy, silver stains (e.g., Warthin-Starry). Cannot be cultured in vitro.
  • Transmission: Sexual contact, transplacental (congenital syphilis).
  • "The Great Mimic": Diverse clinical manifestations across stages. Treponema pallidum morphology and structure

T. pallidum possesses endoflagella (axial filaments) located in the periplasmic space, causing its characteristic corkscrew motility and facilitating tissue invasion.

Clinical Stages - Spirochete's Journey

  • Incubation: 9-90 days (average 21 days).
  • Spirochete dissemination occurs early.
  • Primary (1°):
    • Chancre: Painless, indurated ulcer at entry site.
    • Regional lymphadenopathy: Rubbery, non-tender.
    • Heals spontaneously: 3-6 weeks. Syphilis stages and pathology overview
  • Secondary (2°):
    • 2-8 weeks post-chancre (can overlap).
    • Systemic: Fever, malaise, generalized lymphadenopathy.
    • Rash: Maculopapular, non-pruritic; palms & soles characteristic.
    • Condylomata lata: Moist, flat papules in intertriginous areas.
    • Mucous patches; Moth-eaten alopecia.

    ⭐ Highly infectious stage; spirochetemia.

  • Latent:
    • Asymptomatic, seropositive.
    • Early latent: <1 year duration (potentially infectious).
    • Late latent: ≥1 year or unknown (less infectious).
  • Tertiary (3°):
    • Develops 1-30 years after infection. Non-infectious.
    • Gummatous syphilis: Gummas (destructive granulomas) in skin, bone, viscera.
    • Cardiovascular syphilis: Aortitis, aortic aneurysm.
    • Neurosyphilis: Tabes dorsalis, GPI. (Can occur at any stage).

Neuro & Cardio Syphilis - Late-Stage Havoc

  • Neurosyphilis: Manifests years after infection.
    • Meningovascular: Stroke-like symptoms, cranial nerve palsies.
    • Parenchymatous:
      • Tabes Dorsalis: Sensory ataxia, Argyll Robertson pupil (ARP), lancinating pains, Charcot joints. 📌 ARP: Accommodates but does not React.
      • General Paresis of Insane (GPI): Dementia, personality changes, delusions.
    • CSF: VDRL reactive, ↑protein, pleocytosis.
  • Cardiovascular Syphilis:
    • Aortitis (esp. ascending aorta), aortic aneurysm, aortic regurgitation.
    • "Tree bark" intimal appearance.

    ⭐ Tabes dorsalis features loss of proprioception and vibratory sense. oka

Congenital Syphilis - Inherited Woes

  • Transmission: Transplacental, typically after 4th month.
  • Early (≤2 years): Snuffles (rhinitis), maculopapular rash (palms/soles), hepatosplenomegaly, osteochondritis (pseudoparalysis of Parrot), anemia, thrombocytopenia.
    • Congenital Syphilis Symptoms Diagram
  • Late (>2 years): Hutchinson's triad (interstitial keratitis, Hutchinson's teeth, 8th nerve deafness), saber shins, Clutton's joints, mulberry molars, saddle nose, frontal bossing.

    ⭐ Hutchinson's teeth: Centrally notched, widely spaced, peg-shaped upper incisors.

Diagnosis Decoded - Finding Treponema

  • Direct: Dark Field Microscopy (DFM) identifies motile spirochetes from primary/secondary lesions (chancre, condyloma lata).
  • Serology (Antibody Detection):
    • Non-Treponemal Tests (NTT):
      • VDRL, RPR (Rapid Plasma Reagin).
      • Screening; monitor treatment response (titers ↓ with therapy).
      • 📌 False Positives (VDRL): Viral, Drugs, Rheumatic fever, Lupus, Leprosy, Pregnancy.
    • Treponemal Tests (TT):
      • FTA-ABS, TP-PA, TPHA, specific EIAs/CIAs.
      • Confirmatory; detect specific anti-treponemal antibodies. Usually lifelong positive.

⭐ VDRL is the standard serological test for CSF examination to diagnose neurosyphilis.

Treatment & Prevention - Penicillin Power

  • DOC: Penicillin G.
    • Early Syphilis: Benzathine Penicillin G (BPG) 2.4 MU IM, single dose.
    • Late Syphilis (non-neuro): BPG 2.4 MU IM weekly x 3.
    • Neuro/Ocular: Aqueous Penicillin G 18-24 MU/day IV, 10-14 days.
  • Allergy: Doxycycline (avoid in neuro/pregnancy).
  • JHR: Acute febrile reaction post-treatment.
  • Follow-up: VDRL/RPR titres.
  • Prevention: Partner tracing, safe sex.

⭐ Penicillin G: sole Rx for neurosyphilis & syphilis in pregnancy.

High‑Yield Points - ⚡ Biggest Takeaways

  • Treponema pallidum causes syphilis; primary: painless chancre (use dark-field microscopy).
  • Secondary: maculopapular rash (palms/soles), condylomata lata, lymphadenopathy.
  • Tertiary: gummas, cardiovascular syphilis (aortitis), neurosyphilis (tabes dorsalis, Argyll Robertson pupil).
  • Congenital: early (snuffles); late (Hutchinson's triad: teeth, keratitis, deafness).
  • Serology: VDRL/RPR (non-treponemal for screening/monitoring); FTA-ABS/TPHA (treponemal for confirmation).
  • Treatment: Benzathine Penicillin G. Beware Jarisch-Herxheimer reaction (post-treatment fever).

Practice Questions: Syphilis

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A patient presents with suspected primary syphilis. Which sequence of tests provides the most cost-effective screening approach?

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Flashcards: Syphilis

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_____ syphilis can present with aortitis, particularly of the ascending thoracic aorta

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_____ syphilis can present with aortitis, particularly of the ascending thoracic aorta

Tertiary

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