Lower respiratory tract infections Flashcards
cause of CAP
strep pneumo
types of acute pneumonia
CAP
nosicomial
types of subacute/chronic pneumonia
tuberculosis
fungal
lung abscesses
major diseases caused by strep pneumo
pneumonia meningitis sinusitis otitis media bacteremia
less frequent diseases caused by strep pneumo
endocardiits
spetic arthritis
peritonitis
strep pneumo identifier
gram positive cocci in pairs or chains alpha hemolytic catalase negative optochin sensitive
main mech of strep pneuma pathogenicity
immune evasion
doesn’t release toxins
mechanisms of immune evasion for strep pneumo
capsule prevents phagocytosis
induces inflammation which activates complement and attracts neutrophils
what stimulates strep pneumo cytokine production
peptidoglycan
teichoic acid
virulence factors of strep pneumo
adhesive cell surface components neuramidase and hyaluronidase capsule autolysin pneumolysin
adhesive cell surface components of strep pneumo
teichoic acid
choline binding proteins
protein A
neuramidase and hyluronidase do what
change ECM
capsule
prevents phagocytosis
autolysin
lyses cells which releases peptidoglycan and pneumolysin
pneumolysin
inhibits cillia and neutrophils
promotes inflammation
activates complement system
how is a capsule stained
antibody in Quelling rxn
anti capsule antibodies
appear 5-8 days post infection- marker of immunity
1/3 of adults make them, rest do not
capsular based strep pen vaccine
stimulates IgM and IgG production via capsular polysaccharides from 23 strains
protein conjugated strep pneumo vaccine
capsular polysaccharide conjugated to a protein (tetanus or diphtheria)
induces T cell memory
what vaccine do you give to
protein conjugated
what vaccine do you give to >4
capsular based
pathogenesis of strep pneumo
bacteria grow into alveolar spaces which activates complement and vasoactive factors
bacteria accumulate
exudate and WBC migrate into alveolar spaces