Flashcards in Infection Deck (188)
How does phagocytosis occur?
PRR recognises PAMP
Pseudopods engulph and ingest microbe forming phagosome
Phagosome fuses with lysosome
Microbe digested leaving residual body
Waste discharged from cell
How do phagocytes kill the microbes..
Lysozymes, lactoferrin, proteolytic enzymes
What chemical pathways are involved in second line innate immunity?
How is complement activated?
Classical pathway - antibody antigen complex
Alternative pathway - cell surface on microbes (e.g. LPS)
Mannose binding lectin - MBL binds to mannose on pathogen
What are the active components of compliment? What do they do?
C3a and C5a - chemotaxis
C3b and C4b - opsinisation
C5-C9 - membrane attack complexes
What are the effects of macrophage derived chemical in second line innate immunity?
Increase vascular permiability
Increase body temperature
What chemicials do macrophages release?
In what conditions are second line defences of innate immunity compromised?
Decreased neutrophils (leukaemia, chemotherapy)
Decreased neutrophil function
Define a healthcare related infection
An infection arising from a consequence of healthcare both within and out of hospital
How are hospital acquired infections differentiated form normal infections?
An infection that was neither present nor incubating at the time of admission (onset of symptoms >48 hrs after admission
What are the most common categories of healthcare related infections? What is the in hospital prevalence..
Gi and utis
What can we do to reduced healthcare related infections regarding patient factors?
Optimise physical health
Appropriate choice of medications (e.g. Decreased cephalosporins)
What can we do to reduced healthcare related infections regarding place factors?
Bed layout with siderooms for high risk patients
Pressure isolation rooms
Sink and toilets accessible and individual in high risk
Sterilisation and decontamination
What can we do to reduced healthcare related infections regarding practice factors?
Hospital policies (eg. No relative sitting on beds)
Leadership up to government level - incentives work
Healthcare worker vaccinations
What are the subdivisions of streptococcus?
Alpha haemolytic - pneumoniae and viridans
Beta haemolytic - pyrogenes
Non haemolytic - enterococcus
Diseases from strep viridans
Diseases from strep pyogenes
Diseases from strep pneumoniae
Diseases from staphylococcus
Treatment options for staphylococcus infection
Treatments for necrotising fasciitis
Initial broad spectrum like tazocin (pipperacillin and tazobactam)
Once id as strep pyogenes swich to ben pen
Large dose immunoglobulins to neutralise toxins
Antiprotein abx like clindamycin to decrease toxins
Debridment and amputation
Why is travel history important?
Different strains (resistance change and change in detecting)
What do you need to know about in a travel hx
Specific risks (sex, animals, swimming)
Preventative measures taken (prophylaxis, vaccinations, bite prevention)
What should you do with a suspected travel related infection?
Isolate until you know what it is!
Flag as high risk for lab
What are the causes of malaria?
What is the characteristic fever of malaria? Which subtype differs?
3 day cycling, malariae is 4 day cycling
Symptoms of malaria
Fever 3 day cycling
What is the usual incubation period for malaria?
What are the methods of transmission of malaria?
Vector - anaphalies mosquito in endemic region
Cryptic - mosi on a plane arriving at non endemic airport
Iatrogenic - infected equipment