Micro

Question 1

High risk for endocarditis and undergoing

surgical or dental procedures

Answer 1

Amoxicillin

Question 2

Exposure to gonorrhea

Answer 2

Ceftriaxone

Question 3

Prophylaxis of strep pharyngitis in child with prior rheumatic fever

Answer 3

Benzathine penicillin G or oral penicillin V

Question 4

Exposure to syphilis

Answer 4

Benzathine penicillin G

Question 5

Prevention of postsurgical infection due to S aureus

Cefazolin

Answer 5

Cefazolin

Question 6

Prevention of gonococcal conjunctivitis in

newborn

Answer 6

Erythromycin ointment on eyes

Question 7

Pregnant woman carrying group B strep

Answer 7

Intrapartum penicillin G or ampicillin

Question 8

History of recurrent UTIs

Answer 8

TMP-SMX

Question 9

Exposure to meningococcal infection

Answer 9

Ceftriaxone, ciprofloxacin, or rifampin

Question 10

MRSA:

Answer 10

vancomycin, daptomycin, linezolid, tigecycline, ceftaroline.

Question 11

VRE:

Answer 11

linezolid and streptogramins (quinupristin, dalfopristin).

Question 12

Multidrug-resistant P aeruginosa, multidrug-resistant Acinetobacter baumannii:

Answer 12

polymyxins B and

E (colistin)

Question 13

Autoclave

Answer 13

Pressurized steam at > 120°C. May be sporicidal.

Question 14

Alcohols

Answer 14

Denature proteins and disrupt cell membranes. Not sporicidal.

Question 15

Chlorhexidine

Answer 15

Denatures proteins and disrupts cell membranes. Not sporicidal.

Question 16

Iodine and iodophors

Answer 16

Halogenation of DNA, RNA, and proteins. May be sporicidal

Question 17

Hydrogen peroxide

Answer 17

Free radical oxidation. Sporicidal.

Question 18

Mechanism of Resistance:
production of beta lactamases, which cleave the beta lactic ring structure; change in penicillin binding proteins; change in porins

Answer 18

penicillins and cephalosporins

Question 19

Mechanism of Resistance:

formation of enzymes that inactivate drugs via conjugation reactions that transfer acetyl, phosphoric or adenylyl groups

Answer 19

aminoglycosides (gentamicin; streptomycin; amikacin, etc.)

Question 20

Mechanism of Resistance:
formation of methyltransferases that alter drug binding sites on the 50s ribosomal subunit

Active transport out of cells

Answer 20

macrolides (erythromycin, azithromycin, clarithromycin, etc.) and clindamycin

Question 21

Mechanism of Resistance:

increased anti its of transport systems that “pump” drugs out of the cell

Answer 21

tetracyclines

Question 22

Mechanism of Resistance:

changes in sensitivity to inhibition of target enzyme; increased formation of PABA; use of exogenous folic acid

Answer 22

sulfonamides

Question 23

Mechanism of Resistance:

change in sensitivity to inhibition of target enzymes; increased activity of transport systems that promote drug efflux

Answer 23

fluoroquinolones

Question 24

Mechanism of Resistance:

formation of inactivating acetyltransferases

Answer 24

chloramphenicol

Question 25

Penicillins have enhanced activity when used in combination with beta lactase inhibitors such as

Answer 25

clavulanic acid or sulbactam

• these are suicide inhibitors

Question 26

Naficillin and oxacillin are excreted largely in the _______. And ampicillin undergoes extrahepatic cycling but excreted via the ______.

Answer 26

biles; kidney

Question 27

macrocyclic antibiotic (related to macrolides) that inhibits the sigma subunit of RNA polymerase, leading to protein synthesis impairment and cell death ( it is bactericidal against C. difficle)

Answer 27

fidamoxicin

Question 28

Binds to ergosterol

Answer 28

amphotericin B and nystatin

Question 29

Inhibition of squalene epoxidase

Answer 29

terbinafine

Question 30

blocks beta-D gluten synthesis

Answer 30

capsofungin

* works on main component of cell walls (candida and aspergillus)

Question 31

Prevents mitosis by binding tubulin

Answer 31

griseofulvin

Question 32

inhibits fungal protein synthesis

Answer 32

flucytosine

Question 33

Empirically used to treat skin and soft tissue infections ( folliculitis and abscesses) for which Staph aureus is the usual cause?

Answer 33

nafcillin