Background 2

Question 1

in sensitivity testing after how many hours will the lawn of bacteria be visible

Answer 1

24 hours

Question 2

if an organism is sensitive to an anitibiotic there will be what around the disc?

Answer 2

a zone of clearing

Question 3

if the organsm is resistant to the antibiotic it will

Answer 3

grow close to the disc

Question 4

the size of the zone is dependent on the size of the antibiotic molecule and how far it can

Answer 4

diffuse in the agar

Question 5

what is meningitis

Answer 5

the inflammation of the meninges caused by bac, fungi or viruses

Question 6

which bacteria has become a less common cause of meningitis due to vaccination

Answer 6

haemophilus influenzae type b

Question 7

how is meningitis diagnosed

Answer 7

CSF taken by lumbar puncture

Question 8

a sample of CSF is examined for the presence of

Answer 8

red and white cells

Question 9

why is CSF gram stained

Answer 9

to look for the presence of possible organisms as CSF is usually sterile

Question 10

what is done on day 1 of receiving the csf sample

Answer 10

cell count, centrifuged films are made to differentiate white cells and a gram stain is performed, sample plated out to blood and choc agar + sensitivity test

Question 11

what is done on day 2 of receiving the csf sample

Answer 11

plates read, gram stained again, simple biochemistry performed, confirmatory tests set up

Question 12

what is done on day 3 of receiving a csf sample

Answer 12

further tests interpreated, result issues to ward

Question 13

is neisseria meningitidis gram negative or gram positive

Answer 13

gram negative

Question 14

what does neisseria meningitidis appear like

Answer 14

intracellular diplococci

Question 15

is neisseria meningitidis oxidase positive or oxidase negative

Answer 15

positive

Question 16

what else can neisseria meningitidis cause

Answer 16

septicaemia

Question 17

septicaemia is most common in the young by neisseria meningitidis and meningitis is common in

Answer 17

adolescents

Question 18

what is available against some strains of neisseria meningitidis

Answer 18

a vaccine

Question 19

haemophilus influenzae type b is gram negative or gram positive

Answer 19

gram negative

Question 20

describe the morphology of haemophilus influenzae type b

Answer 20

rod

Question 21

where does haemophilus influenzae type b grow

Answer 21

on chocolate agar but not on blood agar

Question 22

haemophilus influenzae type b is dependent on what when tested on a factors plate?

Answer 22

x and v dependent

Question 23

does haemophilus influenzae type b have a vaccine

Answer 23

yes

Question 24

is Streptococcus pneumoniae gram positive or gram negative

Answer 24

gram positive

Question 25

describe the morphology of Streptococcus pneumoniae

Answer 25

diplococci

Question 26

what is Streptococcus pneumoniae sensitive to

Answer 26

optochin

Question 27

Streptococcus pneumoniae strains causing meningitis often have what

Answer 27

a capsule

Question 28

meningitis caused by Streptococcus pneumoniae is most common in the

Answer 28

very young and elderly

Question 29

what is a capsulated yeast which can cause meningitis in patients with HIV

Answer 29

cryptococcus neoformans

Question 30

which staining allows cryptococcus neoformans to be seen in CSF

Answer 30

india ink staining highlights the capsule

Question 31

which agar does cryptococcus neoformans grow on

Answer 31

sabarauds agar

Question 32

how may hours before sufficient bacterial growth is seen with blood cultures

Answer 32

at least 4 hours can be up to 3 or 4 days

Question 33

when there is a positive signal from the machine regarding blood cultures what happens

Answer 33

a sample is taken from the bottle and gram stained

Question 34

once a sample is gram stained from a blood culture what happens

Answer 34

sample plated onto blood culture and other plates as relevant and a sensitivity test prepared

Question 35

what happens on day 2 of blood culture labs

Answer 35

plates from day 1 are read, gram stained again, biochemistry is performed, sensitivity results analysed