Opportunistic Infections Flashcards
Apart from HIV, what is another infection that is severely immunocompromising?
Measles
What technique does Ps. aeruginosa use to form biofilms?
Quorum sensing
What PAMPs does Ps. aeruginosa have?
LPS
Flagellium
What infection is common in diabetes?
Candida
How does Pseudomonas aeruginosa appear on a gram stain?
-ive rods
Why are CF patients more susceptible to Ps. aeruginosa infection?
Abnormal ion transport
Thicker mucus
Impaired mucociliary elevator
Why do you sometimes need bacteriocidals vs. opportunistic infections?
The patients are commonly immunocompromised therefore are unable to kill the pathogen as required (when using a bacteriostatic antibiotic)
What treatment strategy is used to combat Ps. aeruginosa colonisation of CF patients?
Prophylactic treatment from near birth
What are the key aspects of control of Ps. aeruginosa infection?
Reduce risk in susceptible patients
Monitor at risk patients - CF patients
Be alert for infection and treat early
Hand hygiene
Use contact lens and fluid appropriately
Is Ps. aeruginosa catalase positive or negative?
Positive
What type of respiration does Ps. aeruginosa use?
Aerobe or facultative anaerobe
What is a saprophyte?
Any organism that is able to live freely in the environment
What is the pattern of Ps. aeruginosa colonisation?
Transient colonisation of skin, mucous membranes and GIT
What related species of Pseudomonas is one of the most common causes of pneumonia in the NT?
Burkholderia pseudomallei
What is folliculitis?
Infection of hair follicles
Opportunistic infections are often indicative of what?
Another underlying pathology
How does Ps. aeruginosa colonies appear grossly?
Green
Mucoid
Why is Ps. aeruginosa more resistant to antibiotics when in a biofilm?
More capsule
Grows slower
Others
How do the properties of Ps. aeruginosa differ when in a biofilm?
All reduced virulence - less immune stimulation
Less motile
Increased capsule production
Shorter LPS (no O-antigen produced)
Produce DNA to reinforce the biofilm
What conditions does Ps. aeruginosa commonly cause?
Pneumonia
UTI
Sepsis
What is leucopenia?
Deceased number of WBCs
How is keratitis caused by Pseudomonas?
Colonisation of lens fluid
Who was the first to encourage hand hygiene?
Semmelweis
