Microbiology

Question 1

define colonisation

Answer 1

this is the establishment of a microorganism on or within a host

Question 2

what are enterobacteriaceae?

Answer 2

gram-ve facultative anaerobes

Question 3

four ways enterobacteriaeceae cause disease

Answer 3

1. motility (flagella)
2. colonisation (fimbriae)
3. endotoxin (cell wall component)
4. exotoxin (shiga toxin)

Question 4

which enterobacteriaeceae are not mobile?

Answer 4

shigella and klebsiella

Question 5

function of MALDI-TOF mass spectrometry

Answer 5

analyse protein composition of the bacteria cell wall (discriminates against those with similar 16s rRNA)

Question 6

c. diff gram stain

Answer 6

gram +ve bacillus

Question 7

what is a common cause of healthcare-associated diarrhoea

Answer 7

c. diff

Question 8

what allows c. diff to grow

Answer 8

part of the normal flora and when broad-spectrum antibiotics are prescribed it kills off competitive bowel flora allowing c. diff to grow and produce spores

Question 9

standard infection control procedures

Answer 9

• isolation
• cohort nursing
• cleaning
• PPE
• 48hours off work following no further symptoms

Question 10

bacillus cereus gram stain

Answer 10

gram +ve bacillus

Question 11

what causes a bacillus cereus infection?

Answer 11

reheated rice

Question 12

staph aureus gram stain

Answer 12

gram +ve coccus

Question 13

which foods causes a staph aureus infection

Answer 13

milk, meat and fish (food kept at room temperature- preformed toxin)

Question 14

shigella gram stain

Answer 14

gram -ve bacillus

Question 15

how does shigella cause infection

Answer 15

binds to receptors on renal cells, RBCs, etc inhibiting protein synthesis causing cell death

Question 16

E.coli 0157 gram stain

Answer 16

gram -ve bacillus

Question 17

which foods cause an infection with E. coli 0157

Answer 17

beef and raw milk

Question 18

what can a infection with E. coli 0157 progress to?

Answer 18

haemorrhage colitis and haemolytic uremic syndrome (HUS)

Question 19

what is ELISA used for

Answer 19

it can identify toxins (DNA)

Question 20

campylobacter gram stain

Answer 20

gram -ve bacillus

Question 21

foods that cause an infection with campylobacter

Answer 21

poultry and raw milk

Question 22

management of campylobacter

Answer 22

macrolide

Question 23

salmonella gram stain

Answer 23

gram -ve bacillus

Question 24

what food cause an infection with salmonella

Answer 24

poultry, meat, raw egg and animals (bacteraemia from reptiles)

Question 25

which bacteria has an O-antigen

Answer 25

salmonella

Question 26

listeria monocytogenes gram stain

Answer 26

gram +ve bacillus

Question 27

presentation for listeria monocytogenes

Answer 27

fever
muscle aches
diarrhoea

Question 28

what is listeria monocytogenes infection caused by?

Answer 28

unpasteurised milk products and deli counter

Question 29

gram stain of H. pylori?

Answer 29

gram -ve spirlleum