Pseudomonas

Pseudomonas receives its own section to reflect the morbidity associated with poor management of infection.

  • Appreciation of P aeruginosa as being the primary human pathogen

  • Role of moist environments within hospitals as being a potent source of pathogen

  • Basis of infection as being via cytotoxins and damaging proteases

  • Clinical features of infection: eye; ear; skin; bone; CNS; risk of septicaemia

  • Basis of diagnosis via culture

  • Principles of treatment: appreciation of high resistance to antibiotics

  • Implications of pseudomonas infections within the hospital setting

#curriculum #microbiology

damp hospitals and taps
Etiology obligate aerobe, Gram -ve, motile. Not a commensal.
Epidemiology opportunistic infections - immunocompromised - Granulocyte deficiency; hospital; cystic fibrosis, burns...

direct and indirect contact spread
Clinical presentation Gram negative sepsis; contact lens keratitis; otitis externa...
Pathogenesis Virulence factors:
- pili and adherence proteins that bind to epithelial cells and lung mucin
- mucoid exopolysaccharide (alginate) → biofilm

Pathogenesis:
endotoxin
exotoxin A (inhibits protein synthesis), proteases
toxic iron-containing compounds → vascular injury
Diagnostic investigations
Management Tazocin, gentamicin