Microbiology/Immunology

Question 1

HAP - causative organisms

Answer 1

Pseudomonas, S. pneumonia, Klebsiella, E. coli, Enterobacter

Question 2

MHC I

Answer 2

Presents antigens from inside cells to T killer (CD8) cells

Question 3

MHC 2

Answer 3

Presents antigens from outside cells to T helper (CD4) cells - stimulates production of antibodies by B cells

Question 4

Neisseria meningitidis

Answer 4

Gram negative diplococcus

Question 5

Cellulitis - causative organisms

Answer 5

S. aureus, S. pyogenes

Question 6

Cellulitis - first-line ABx

Answer 6

Flucloxacillin - beta-lactamase stable

Question 7

E. coli serotype O157

Answer 7

Commonly found in beef, causes bnnloody diarrhoea, may cause haemolytic-uraemic syndrome (esp. in kids)

Question 8

TB treatment

Answer 8

4 drugs for 2 months (isoniazid/rifampicin/ethambutol, pyrazinamide), then 2 drugs for 4 months (isoniazid/rifampicin) - if CNS involvement increase Rx to 12 months

Question 9

Herpes simplex encephalitis is most likely to affect

Answer 9

Temporal lobe

Question 10

1st-line treatment for infective endocarditis

Answer 10

Amoxicillin and gentamicin

Question 11

Measles - infective period

Answer 11

3 days before and 4 days after appearance of rash (so total of 7 days)

Question 12

Membrane attack complex

Answer 12

Formed by C5-C9, needed to fight Neisseria

Question 13

C3 action

Answer 13

Coats encapsulated bacteria - marks for phagocytosis

Question 14

Whooping cough is contagious for

Answer 14

3 weeks after onset of symptoms