USMLE

Chlamydia trachomatis

969 views
Bacteria - Gram Negative
  1. Neisseria spp: Overview
  2. Neisseria gonorrhoeae
  3. Neisseria meningitidis
  4. Haemophilus influenzae
  5. Bordetella pertussis
  6. Brucella
  7. Legionella pneumophila
  8. Pseudomonas aeruginosa: Overview
  9. Pseudomonas aeruginosa: Disease
  10. Salmonella Overview
  11. Salmonella typhi
  12. Salmonella enteritidis
  13. Shigella
  14. Yersinia enterocolitica
  15. Escherichia coli: Overview
  16. Enterohemorrhagic E. Coli (EHEC)
  17. Enterotoxigenic E. Coli (ETEC)
  18. Klebsiella pneumoniae
  19. Campylobacter jejuni
  20. Vibrio spp.
  21. Helicobacter pylori
  22. Borrelia burgdorferi (Lyme Disease)
  23. Leptospira interrogans
  24. Treponema pallidum: Overview
  25. Treponema pallidum: Diagnosis
  26. Congenital syphilis
  27. Chlamydia: Overview
  28. Chlamydia trachomatis
  29. Chlamydia pneumoniae vs. psittaci
  30. Rickettsia rickettsii
  31. Rickettsia typhi vs. prowazekii
  32. Anaplasma vs. Ehrlichia
  33. Coxiella burnetii (Q fever)

Chlamydia trachomatis

  • Transmission
    • C trachomatis is sexually transmitted
  • Presentation
    • Trachoma (eye infection)
      • Serotypes A, B, C 
      • May be complicated by blindness
    • Urethritis or cervicitis
      • Serotypes D-K
      • Presents with dysuria and cervical irritation
      • Rarely presents with orchitis in sexually active men
      • Can be complicated by pelvic inflammatory disease (PID)
        • Scarring may lead to ectopic pregnancy and infertility
      • Can pass to neonate via birth canal
        • pneumonia (staccato cough) with eosinophilia
        • conjunctivitis (1-2 weeks after birth)
    • Lymphogranuloma venereum (LGV)
      • Serotypes L1, L2, and L3
      • Painful lymphadenopathy
        • Classic feature of LGV
        • swollen inguinal lymph nodes may ulcerate, creating genital buboes
      • Treat with doxycycline
    • All infections may be complicated by reactive arthritis 
      • Asymmetric joint arthralgias, conjunctivitis, and urethritis
        • “Cant see, can’t pee, can’t climb a tree”
  • Diagnosis
    • Cytoplasmic inclusions seen on microscopy
      • By Giemsa staining or fluorescent antibody-stained smear
    • PCR or nucleic acid amplification test (NAAT) is the gold standard
      • Not frequently tested since it is too obvious
  • Treatment
    • Rule out N. gonorrhoeae or empirically treat for coinfection
    • Macrolide (azithromycin) or doxycycline
      • Topical and oral macrolide (erythromycin) for neonatal chlamydial conjunctivitis