Host Infection Interactions Flashcards
What are some defences present in the conducting airways?
Mucociliary escalator (e.g cough) Cellular and humeral immunity
Does intubation increase the risk of infection?
Yes
What causes impaired gas exchange in pneumonia?
Fluid and cellular build up in the alveoli
What is the most common cause of community acquired pneumonia?
Strep pneumoniae
What does cystic fibrosis cause?
Abnormally viscous mucous = repeated chest infections and chronic colonisation
What are some bacteria associated with cystic fibrosis?
Burkholderia cepacia, pseudomonas aeruginosa, staph aureus
How do varicella zoster and herpesviridae viruses evade the immune system?
Hide in neuronal and non-neuronal cells = emerge in pathogenic form when host has lowered resistance
What kind of bacteria is burkholderia pseudomallei?
Gram negative bacilli = causes TB-like illness up to 60 years after initial infection
How does leishmania avoid the immune system?
Interferes with IL-12 transcription
What CD4+ count would indicate high level of immunosuppression?
CD4+ <200
At what CD4+ level does TB infection commonly occur?
CD4+ of 200-500
What is oral candidiasis a sign of in HIV patients?
Severe immunosuppression = CD4+ <100
What are some sources of infection in a person presenting <1 month after transplant?
Hospital acquired, previous colonisation before transplant or due to donor infection
What is the risk of invasive aspergillosis in transplant patients?
4-40% depending on the type of transplant
What are some factors that increase risk of infective aspergillosis?
High level of net state immunosuppression
Previous infection with CMV
