Medicine & USMLE

Pseudomonas aeruginosa: Disease

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)

Pseudomonas aeruginosa disease 

  • Presentation
    • 4 main groups of people affected
      • Exposure to contaminated water of hot tubs/pools
        • Malignant otitis externa (MOE)
          • Severe infection of outer ear tissue exposed to water
          • Presents with severe pain and drainage
          • Untreated conditions can progress to osteomyelitis of skull
        • Rash (“hot tub folliculitis”)
          • infection of hair follicles exposed to contaminated water
          • Itchy, papulopustular rash over trunk and extremities
      • Cystic Fibrosis
        • Pneumonia 
          • Increased viscosity of airway in CF mucus impairs mucociliary escalator to clear bacteria
          • Recurrent respiratory infections with P. aeruginosa, diarrhea/steatorrhea, and failure to thrive are classic
      • Immunocompromised patients
        • Ecthyma gangrenosum
          • Rapidly progressive necrotic lesion that is manifestation of Pseudomonas bacteremia
          • Exotoxins and invasion of bacteria destroy blood vessels and surrounding tissue, causing necrosis
        • Often seen in patients with low absolute neutrophil count (e.g. cancer post-chemo, bone marrow transplant)
      • Indwelling (Foley) urinary catheter
        • UTIs (urinary tract infection)
    • Osteomyelitis may be seen in IV drug users/diabetic patients
    • Corneal ulcers/keratitis may be seen in contact lens wearers
    • Wound infection may be seen in burn victims
  • Treatment 
    • Piperacillin, ticarcillin
      • Only some extended spectrum penicillins are effective
    • Ceftazidime, cefepime
      • Note: ceftriaxone is NOT effective
    • Fluoroquinolones (e.g. ciprofloxacin, levofloxacin)
    • Carbapenems (e.g. meropenem, imipenem)
    • Aminoglycosides
    • Monobactams
    • Polymyxins (e.g. polymyxin B, colistin)