Microbiology

Question 1

Which bugs are lactose fermenters?

Answer 1

1. Klebsiella
2. Enterobacter
3. Serratia
4. E. coli

Question 2

Which is motile? (Enterobacter/ Serratia/ Klebsiella)

Answer 2

Enterobacter and Serratia

Question 3

which has a polysaccharides capsule? (Enterobacter/ Serratia/ Klebsiella/ E. coli)

Answer 3

Klebsiella and E. coli

Question 4

Which causes pneumonia with ‘currant jelly sputum’? (Enterobacter/ Serratia/ Klebsiella/ E. coli)

Answer 4

Klebsiella

Question 5

Which is catalase (+) ?

Enterobacter/ Serratia/ Klebsiella/ E. coli

Answer 5

E. coli are cat (+)

Enterobacter, Serratia, Klebsiella are cat (-)

Question 6

Which has fimbrae to attach to uroepithelial cells to cause UTI?
(Enterobacter/ Serratia/ Klebsiella/ E. coli)

Answer 6

E. coli

Question 7

The fimbrae used by E. coli to attach to uroepithelial cells is called virulence factor ___

Answer 7

Factor P, type 1

Question 8

Which can cause hemorrhagic pneumonia in alcoholic men? (Enterobacter/ Serratia/ Klebsiella/ E. coli)

Answer 8

Klebsiella

3A’s: alcoholics, aspirations, abscesses

Question 9

Which can cause endocarditis in heroin users? (Enterobacter/ Serratia/ Klebsiella/ E. coli)

Answer 9

Serratia

Question 10

What bug is the most common cause of gram (-) sepsis?

Answer 10

E. coli

Question 11

Which has K antigen on it’s capsule, seen in meningitis?

Enterobacter/ Serratia/ Klebsiella/ E. coli

Answer 11

E. coli

Question 12

which causes hemolytic uremic syndrome?

Enterobacter/ Serratia/ Klebsiella/ E. coli

Answer 12

E. coli O157:H7

Question 13

Which has ‘swarming motility’ when plated? (Proteus/Providencia/Morganella)

Answer 13

Proteus

Question 14

Proteus/Providencia/Morganella cause UTI’s with struvite stones using their _______ virulence factor

Answer 14

urease, creates alkaline environment

Question 15

Which is gram (+) (enterobacter/ enterococcus)

Answer 15

Enterococcus is (+)
Enterobacter is (-)

Question 16

What type of cell is most responsible for acute graft rejection?

Answer 16

CD 8+ T-cells against donor MHC

Question 17

What is the mechanism for hyperacute transplant rejection e.g. missmatched blood transfusion

Answer 17

Pre-existing antibodies, a type II HSR

Question 18

What type of cell is most responsible for chronic transplant rejection?

Answer 18

CD 4+ T cells responding to APC that have collected donor antigen

Question 19

To avoid transplant rejection drugs daclizumab and basiliximab target the _________ receptor on activated T cells

Answer 19

IL-2 receptor

Question 20

Belatacept prevents transplant rejection by blocks co-stimulation of T-cells by binding ________

Answer 20

B7

Question 21

FK506 and cyclosporine inhibit T-cell signaling pathways, prevent IL-2 secretion by inhibiting __________

Answer 21

Calcineurin, a t cell activator

Question 22

Under what circumstances would a bone marrow transplant resulting in GVHD be a good thing?

Answer 22

Leukemia, graft-vs-host disease would help kill the residual tumor

Question 23

When pre-formed antibodies react with transplanted tissue it is (acute/ hyper-acute/ chronic) rejection

Answer 23

hyper-acute

Question 24

What is an ‘alloantibody’?

Answer 24

An antibody directed against transplanted tissue

Question 25

How does Azathioprine, the mycophenolic acid derivative prevent transplant rejection?

Answer 25

It is cytotoxic to rapidly proliferating (B and T) cells

Question 26

What classes of drugs are used for the induction of immunosuppression during transplantation?

Answer 26

1. Anti-lymphocytic globulins

2. Monoclonal antibodies (to CD 52, or IL-2)

Question 27

What 3 classes of drugs are used for maintenance of immune suppression for a transplant recipient?

Answer 27

1. corticosteriods, e.g. prednisone
2. Cytotoxic drugs, mycophenolic acid derivatives
3. calcinurin inhibitors, FK 506 and cyclosporine