this is an oxidative organism, GNB, which produces 2 pigments, pyocyanin and pyoverdin. On NA, the colonies have a characteristic greenish colour. It also produces a distinct smell. Open the plate and pass it quickly past your nostrils. Dont inhale too eagerly and dont leave the plate open for long.
the identification rests on:
colonial morphology on agar plates
characteristic colour and smell
reactions in OF/Hugh Leifson medium acid in open and closed tube, oxidative reaction
oxidase reaction positive
this organism is very fond of damp/moist areas so it colonises readily anything that has "standing" water. It has a strong unhealthy relationship with cystic fibrosis patients. These patients produce the alginate gene. This gene is activated to produce alginate which surrounds the cell wall of the organism and therefore protects it against phagocytosis.
Now picture this:
the organism produces many toxins/enzymes that destroy elastin, collagen, lipase which all allow the organism to spread the infection
the pigment pyocyanin stops other bacteria from causing an infection at then same time
the organism destroys the RBC and produces toxic effects in the patient
the organism is resistant to most of the antibiotics used for GNB infections. So any antibiotic used will produce serious side effects in the patient
What a nasty little buggar??
And to top it all, it is capable of growing at room temp, body temp and at 42 degrees. So a fever in the patient wont kill this little horror!!!
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