Pseudomonas aeruginosa

Microbiology

• Oxidase-positive, non-fermenting Gram negative bacillus

Mechanisms of Resistance

• Broad intrinsic and acquired antibiotic resistance
• Membrane impermeability
• MexAB-OprM efflux pump
• Acquired mutations
• Inducible AmpC β-lactamase
• Plasmid sharing

Environment and Infections

• Loves moist and wet environments
• Causes healthcare-associated infections
  • UTI, SSI, bacteremia, HAP, VAP
  • Especially common in cystic fibrosis

Treatment

• See Antipseudomonal antibiotics
• Double coverage (ß-lactam + non-ß-lactam) in cases of severe infection in order to ensure activity against the infection