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Flashcards in M6 Staphylococcus Deck (49):
1

what are some major strains of staphylococcus

s. aureus
s. epidermidis

2

what are some common features of staphylococcus

gram +ve
non motile
irregular shape
aureole and facultative anaerobe
catalase +ve
oxidase -ve
can be coagulase +ve or -ve

3

how common is s. aureus

20% colonisation

4

where is s.aureus common

anterior nares and perineum
nosocomial and community

5

what is MRSA

mainly nasocoimal
elderly and immunosuppressed
ICU

6

what is the colonisation of s.epidermidis

100%

7

where is s.epidermidis found

skin and mucous mems

8

what si a nosocomial infection

assc with forgein devices - catheters

9

what is the common direct contact transmission of staph

hand and skin or mucous

10

what is the common indirect transmission of staph

instruments
bedding
door handles

11

what si the way staph is air bourne

shedding of cocci from infected site into atmosphere
dust or squames

12

what kind of bac is staph

oppputunisit

13

what are staph means of entry

hair follicles and sebaceous glands
damaged or diseased skin
broken skin
catheters
post influenza pneumonia

14

what is the pathogenicity of s. aureus

superififcal lesions - build to abscess
systemic - life threat
toxinoses - toxic shock

15

what sit he carriage of s. aureus

anterior nares
perineum
hands
oral cav - age and pros

16

what is the significance of s. aureus

HAI/nasocomial
oral abscesses
head and neck - ottis media

17

what are the virulence factors of staph

attachement
evasion of host defences
invasion/ tissue penetration

18

what are some virulence factors

capsule
coagulate
fibrinogen bind protein
TSST-1
adhesins
kills leucocytes
shock
rash
desquamation

19

what are adhesins

extracellular matrix molecules are present on epi, endo surfaces as well as a component of blood clots

20

what is imp about fibrinogen binding

fibriiognen cleave from fibrin monomers allows to colonise site

21

wha are some s aureus skin infection

folliculitis
carbuncle - multiolbualr abscess
impetigo
abscess
scalded skin syndrome

22

what are some subs used for evasion of host defences

protein A
proteases
superantigens
lipases
coagulate
capsule

23

what are toxinoses

TSST-1 toxic shock syndrome toxin 1
rapid progression high fever, sore throat, muscle pain

24

what is the bacteria present in food poisoning

staphylococcal enterotoxin

25

what is SSS

scalded skin syndrome
exfoliatin toxins
neonatal
face, axilla, groin

26

what are superanitgens

bind to outside and staalises reaction in 1/10 T cells turning whole immune system on
assc with toxic shock
massive release cytokines

27

what is diagnostic criteria of TSST-1

fever 39
diffuse macular rash - erythroderma- water under skin
hypotension
organ systems failing

28

what does protein A do

bind to Fc region of IgG antibodies
produced by exponential growth

29

what is protein a

coagulase +ve
activation complenent

30

what do pretences do

cleave Ab, defnesins, platelet microbicidal proteins
destroy host tissue

31

hat are lipase, phospholipase and esterase

combat surfactants produced to disrupt bacterial mem
post exponentially expressed scavenging enzymes

32

what is Panton Valentine Leukocidin

PVL bicomponent toxin
sp toxicity for leucocytes
1-2% strains
assc with severe skin infections

33

what are PVL and alpha toxin linked with

CA-MRSA
responsible for necrotising pneumonia and contagious severe kin infections

34

what is necrotising pneumonia

preceding influenza like syndrome
rapid progression
acute resp distress
refractory hypoxamenia young and fit community acquired

35

what si coagulase

plasma
protective allows clot and ashore but also covers assess host proteins such as fibrin

36

wat does coagulase form

staphylothrombin promotes conversion of fibrinogen to fibrin and clotting

37

what is coagulase +ve example

synonymous with pathogenic staphylococci

38

what is an example of coagulase +ve an -Ve

+ve - s.aureus
-ve - s. epidermis

39

what is fnbA

fibronectin adhesin

40

what is cna

colagen ashesin

41

what is sdrE

bone sialo-bindig

42

what is hlg

gamma toxin (leukocidin)

43

what is ica

polysaccharide intracellular adhesin

44

what si themes common HAI strain

t032

45

what is the regulation of pathogenicity factors

transition to exponential protein a,fibronectin binding proteins, surface proteins, coagulase

late expo surface proteins tuned off

stationary has secreted proteins turned on

46

what si most common antibiotic treat

peniccilin

47

what is issue with penicillin

50-80% resistant (beta-lactamase +ve)

48

what is flucloxacillin

beta - lactase resistant use if can't use penicillin

49

if allergy to penicillin what is used

erythromycin