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Flashcards in RT5 Deck (42)
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1

major contributors to pathogenesis of influenza virus

T cell response, interferon induction, desquamation of mucus secreting and ciliated cells

2

what is antigenic shift

sudden rearrangement of the 8 genetic subunits which results in major changes of HA and NA genes and is responsible for pandemics/epidemics

3

what is antigenic drift

gradual accumulation of point mutations in genes encoding HA and NA leading to gradual loss of stereospecificity of the Ag-Ab bond (most impo in HA because effect of neutralizing Ab is lost)

4

antigenic shift and drift is seen in which influenza

antigenic drift is seen in all 3 (with C being less frequent)

antigenic shift is only seen in A

5

how do you diagnose influenza

clinical diagnosis based on symptoms and laboratory diagnosis

6

anti flu drugs

amantadine, rimantadine, zanamivir, oseltamvir (tamiflu)

7

how does amantadine and rimantadine work

by inhibiting the uncoating of type A only since its target is the M2 protein

B and C do not have the M2 protein

8

how does zanamivir and oseltamvir work

inhibits neuraminidase -- hence forcing virus to bind to its own sialic acid and form useless clump

essentially virus will not be released from the cell in Type A and B only since C does not have NA

9

what happens with constant use of antimicrobials to treat the flu

we start to build drug resistance

10

do we build acquired immunity to the flu and is it effective

we do but it is weak because the antigen changes constantly

11

which influenza has an animal reservoir

just A

12

another name for subacute LRT infection

walking pneumonia, atypical pneumonia

13

prokaryotes for subacute LRT infection

mycoplasma spp, chlamydia spp, legionella sp, miscellaneous viruses

14

eukaryotes for subacute LRT infection

usually fungi: histoplasma sp, blastomyces sp, coccoididiodes sp, candida sp

15

findings in primary atypical pneumonia

low grade lung infection that resolves around 18 days, a little fever but it only lasts a few days

16

common cause of walking pneumonia/atypical pneumonia/subacute LRT infection

mycoplasma

17

walking pneumonia with mycoplasma is common in what population

children greater than 5 years old - young adults

18

clinical syndrome of streptococcus pneumonia

pneumonia, sinusitis, and otitis media

19

describe strep pneumonia on a blood agar

-sensitive to optochin (P disk)
-does alpha hemolysis which involves a change in the redox potential of RBCs making it less red which is not as transparent as s. pyogenes that does beta hemolysis

20

commonest cause of community acquired pneumonia

strep pneumonia

21

what type of infection is strep pneumonia

it is both exogenous and endogenous
endogenous - it is within us to start with already
exogenous - if we pass ours to another human it becomes exogenous

22

pathogenesis of strep pneumonia

capsule, IgA protease, pneumolysin, autolysin, transformation

TAPIC

23

properties of pneumolysin

inhibits ciliated epithelial cell activity, cytotoxic for alveolar and endothelial cells, causes inflammation, decreases PMN effectiveness

24

prevention of strep pneumonia

polyvalent capsular polysaccharide vaccine , 7-valent conjugated vaccine

25

clinical syndrome of klebsiella pneumonia

bronchopneumonia and lung abscesses

26

general features of klebsiella pneumonia

-non motile, gram neg bacillus with a large capsule that has smooth/mucoid appearance
-part of normal flora
-uses aerobactin and enterochelin to uptake iron from host

27

pathogenesis of klebsiella pneumonia

it is gram neg so --> release of endotoxin --> necrotizing of lung tissue

28

diagnosis of klebsiella pneumonia

sputum will have red currant jelly appearance

29

clinical syndrome of legionella pneumophila and transmission

legionnaires disease (pneumonia)
pontiac fever

inhalation of contaminated aerosols (Rare)

30

general features of legionella pneumophila

gram neg, motile, non spore forming, facultative intracellular (alveolar macs)