infection extra- sepsis Flashcards
Where in the body can N. meningitidis be found as part of the normal flora?
N. Meningitidis can be found normally in the nasopharynx (nose and throat).
It does not cause any problems here, until it overgrows and enters the bloodstream.
Which of these is the most appropriate empiric antibiotic when treating meningicoccal sepsis
Ceftriaxone
because it has good CSF penetration, which is important when treating meningitis.
Which antibiotic is the empiric choice for non-meningococcal suspected sepsis in adults?
Meropenem
it is a broad spectrum antibiotic that acts best on gram positive bacteria.
in adults, sepsis is more commonly caused by gram ? pathogens ?
in adults, sepsis is more commonly caused by gram positive pathogens.
function of CRP?
Opsonin-mediated phagocytosis.
CRP binds to the phosphocoline expressed on the surface of dead/dying cells and some bacteria.
Activates the complement system, promoting phagocytosis by macrophages > clears neurotic and apoptotic cells and bacteria.
why is blood cultures so important in sepsis?
must take blood cultures BEFORE ABX treatment!
fever is caused by?
when patient has infection of throat
Macrophage-derived Interleukin-6 (cytokine) acting on hypothalamus
(see innate immune lecture)
response of monocytes in regard to bacteria in blood?
produce cytokines (IL6, IL1, TNF) > trigger fever
raised neutrophil count is indicative of which infection?
role of neutrophil?
bacterial
neutrophils are main cell that phagocytose (macrophages can also do it)
Streptococcus pneumoniae features?
gram positive coccus
grows in chains
commonly found in pairs
is a type of alpha streptococcus
>agar plate shows partial haemolysis (alpha) - green colour
what is a phagolysosome?
late vesicle when phagosome fuses with lysosome
which test gives the best microbiological answer within 6 hours to help select appropriate ABX?
gram stain