M27 Infective Endocarditis Flashcards Preview

Microbiology 2 > M27 Infective Endocarditis > Flashcards

Flashcards in M27 Infective Endocarditis Deck (43):
1

what is IE caused by

micro organisms settling on heart valves (bac/fungi)

2

is IE fatal

yes without treatment

3

how does IE come about

predisposing lesion on valve
attracts layer of platelets/fibrin
sticky surface
bac attch
VEGETATION
infection develops

4

how do pathogens causing IE get into the bloodstream

diff routes
injury
oral cav
catheter

5

how to pathogens rapidly adhere

platelet fibrin deposition

6

what do some sp do

obtain intracellular access

7

what does embolisation or heamatogenous spread lead to

range of complications
- stroke
- meningeal infections

8

what are some clinical effects of IE

bacteraemia
damage to valve form vegetative growth
emboli
immune complex effects

9

what is bacteraemia diagnosis linked to

positive blood culture

10

how can a valve be damaged by vegetative growth

valve rupture
mitral/atrial

11

how do emboli effect the body

bits flake off and lodge into small vessels
stroke etc

12

where ca remote embolic effects be seen

often found on extremities or mucous mems

13

what is palatal petechiae assc with

IE
Leukemia
STD
Viral infection - infectious mononucleosis

14

what are th two sources of bacteriamia

spontaneous and induced

15

what is the spontaneous source of bacteriaemai

oral flora
gut flora

16

what is induced cause of bacterimia

gum margin manipulation - extraction
IVDU

17

what are the types of organisms assc with IE

staphylococci -25%
streptococci - 50-70%
enterococci - 10%
Candida
culture negative

18

what are the specifics of the staphylococci involved in IE

coagulase - ve - epidermis
causing rapid valave degeneration

19

does candida and colifrms usually seen to cause IE

uncommon

20

what are the assc culture negative bacteria in iE

HACEK
haemophilia
aggregatibacter
eikenella

21

what si he percentage of IE cases oral origin

20%

22

what are some key concepts when thinking of virulence in IE

entry/circ blood
adherence - platelet/fibrin
biofilm form
host cell invasion
aggressive damage
sec toxins
intracellular persistence

23

what re some surface adhesins assc with streptococcus gordonii

PadA
Hsa

fro platelet adhesion and aggregation

24

what are pt most at risk of IE

individuals with damage heart valves
history
IVDU
prothetic valves
cardiac surgery

25

what are some symptoms of subacute

malaise
headache
night sweats
rigors
heart murmur
embolic manifestations
immune complex disease

26

what are some symptoms of a high index of suspicion

fever and unknown cause
murmur
heart lesion
bacteriamia
malaise
positive blood culture

27

what are some other ways of identifying IE

echocardiography
C relative protein (marker of inflam)
serology

28

what is the principle of treatment

empiric therapy
- tidal
- large dose
- long time

29

when is Ab started for IE

after blood cultures
for acute infection s aureus targeted

30

what bac is targeted particularly with beta lactam

gm +ve cocci

31

what are the Ab used in therapy

beta lactase
gentamicin
vancomycin
rifampicin

32

what are some beta lactams

amoxicillin
benzyl penicillin
flucloaxacillin

33

what does gentamicin do

coliforms and synergy with beta lactamsfor strept

34

what does vancomycin do

ag MRSA/ s epidermidis
less active used with something

35

what does rifampicin do

penetrates well and synergy with vancomycin not alone or get resist

36

what is used for native valve acute/sever

flucloxacillin

37

what is used for native valve subacute

amoxicillin and gentamicin

38

what is used for prosthetic valve

vancomycin
gentamicin
rifampicin

39

what is sued for MRSA

vancomycin
gentamicin
rifmpiicin

40

is suspected s aureus causing what is sued

high dose flucloxacillin

41

is suspected enterococci is the cause use

high does amoxicillin and gentamicin

42

is suspected Viridans Group Streptococci

high dos penicillin
4 weeks

43

when is prophylactic prescribing considered

medical status
immunological status
preceding infection at site
invasiveness of procedure