Organism Characteristics:
*Bacteria Form: Gram-Negative rod Family:
This is an opportunistic pathogen and requires a susceptible host. it likes disruptions of physical barriers (iv, catheter, ET tubes), immune dysfunction, and broad spectrum antibiotics (disrupts normal microbiome)
Virulence mechanisms:
- has biofilms (bad in CF) and capsules
- Made of Alginate and polysaccharide (EPS)
- Allows for Immune evasion
- Allows for Antimicrobial resistance
- motility (unipolar flangella)
- chemotaxis can occur (moves to sugars in the respiratory mucous (Bad in CF))
- Adhesins
- lets them stick to surfaces in biofilms
- Invasins
- break apart barriers which allows further spread
- Affect host rewsponse
- lleukocidins
- proteases
- catalase
- Toxins
- LPS (automatically recognises)
- Exotoxin A (stops protein synthesis)
- Pyocyanin (makes pus blue-green)
Resistances:
It usually lives in soil and so has a great number of resistances
- multidrug resistant (it lives in soil so has lots of experience with naturally invented antimicrobials)
- multiple drug resistance machanisms
- efflux pumps
- Porins
- ß-lactamases
- can rapidly acquire resistance
- very plastic genome
- gene transfer
- makes biofilms
Infection
Areas colonised in the body (Microbiomes):
3-5% of people are colonised (Skin and gut) but 20% of hospital inpatients are colonised.
Hospital acquired illnesses?
Yes with significant mortality
Clinical
Associated illnesses:
A long list (thanks McBurney):
- LRTI
- sepsis
- bone and joint infections
- UTI
- Eye and Ear infections
- Wound infection (burns)
- Folliculitis
Testing and identifications:
Pyocyanin makes pus blue-green
Treatment and therapy:
Antipseudomonal penicillin + aminoglycoside Antipseudomonal penicillin + ß-lactamase inhibitor or broad spectrum drugs
- carbapenems
- colistin