Syphilis

• Sometimes called lues
• Treponema pallidum
• Risk factors
  • Men who have sex with men
  • Promiscuity
  • Unprotected sex
• Incubation period 10 – 90 days (average 21)
• Has 4 characteristic stages
  • Primary syphilis
    • Characterised by a special lesion called a chancre
    • Chancres occur at the site where the bacterium enters the body
    • It’s a painless, firm ulcer with indurated borders and a smooth base
    • Chancres resolve spontaneously without scarring after 3 – 6 weeks
  • Secondary syphilis
    • Known as the “great imitator” as its skin symptoms resemble those of many other skin diseases
    • Both systemic and mucocutaneous lesions
    • Begins 8 – 12 weeks after primary infection
    • Lasts 2 – 6 weeks
    • Disseminated, symmetric rash
      • Polymorphic, i.e. can take on many appearances
      • Typically nonpruritic macular or papular rash
      • Reddish-brown
      • Roseola syphilitica = macules on trunk and flexor aspects of the extremities
      • Corona veneris
        • Maculopapular lesions
        • On forehead or back of neck
      • Clavus syphiliticus = maculopapular lesions on palms and soles
    • Mucous patches
      • White patches on mucous membranes
    • Condyloma lata
      • Broad-based, wart-like papular erosions
      • In anogenital region, intertriginous folds, oral mucosa
    • Patchy alopecia
    • Leucoderma syphiliticum
      • Hypopigmentation
      • Necklace of Venus = hypopigmentation around the neck
      • Differential diagnosis: pityriasis versicolor
    • Non-cutaneous and non-mucosal symptoms
      • Pharyngitis
      • Iritis
      • Hepatitis
      • Generalized nontender lymphadenopathy
      • Meningitis
  • Latent syphilis
    • The patient is seropositive but there are no symptoms
    • Can last months, years or the rest of the patient’s life
    • There are four outcomes
      • The disease resolves and the patient becomes healthy
      • The disease reactivates as secondary syphilis
      • The disease progresses into tertiary syphilis
      • The patient dies before any of these outcomes occur
  • Tertiary syphilis
    • Occur in approx. 30% of untreated patients in the latent stage
    • Late benign syphilis
      • Gummas
        • Destructive and ulcerative granulomatous lesions with necrotic centre
        • Can occur anywhere on or in the body, even on organs and bones
      • Nodules
      • Psoriasiform granulomatous lesions
    • Cardiovascular syphilis
      • Aortitis with resulting aneurysm of the aorta
      • Dilated aortic root
    • Neurosyphilis
      • Early neurosyphilis
        • Meningitis
        • Stroke
      • Late neurosyphilis
        • Tabes dorsalis
          • Demyelination of the dorsal column and dorsal root ganglia
          • Causes a broad-based ataxia
        • Dysesthesia
        • General paresis
        • Widespread cerebellar atrophy
        • Dementia
        • Argyll Robertson pupil (Bilateral miosis, pupils don’t react to light)
  • Diagnosis
    • Direct visualization of treponema
      • In the primary stage, when the serological tests below can be negative
      • Darkfield microscopy
      • Specimen from a lesion
    • Nontreponemal tests – for screening
      • RPR
      • VDRL
      • Sensitive, not specific
    • Treponemal test – for confirming the diagnosis
      • TPPA
      • FTA-ABS
      • Specific, not sensitive
  • Treatment
    • For prevention, primary, secondary and early latent syphilis
      • 2,4 million units of benzathine penicillin G intramuscularly – single dose
    • For tertiary (except neurosyphilis) and late latent syphilis
      • 2,4 million units of benzathine penicillin G IM – once weekly for three weeks
    • For neurosyphilis
      • IV penicillin G for 10 to 14 days
    • Jarisch-Herxheimer reaction may occur
      • Systemic reaction to bacterial endotoxins
      • Is usually self-limiting
    • In case of penicillin allergy
      • Doxycycline
      • Desensitization to penicillin, then use penicillin as normal