Antibacterial Agents IV

Question 1

What three fluoroquinolones do we need to know for class?

Answer 1

Levofloxacin, ciprofloxacin, and moxifloxacin

Question 2

What combination of DNA precursor methylation is bactericidal?

Answer 2

Trimethoprim-sulfomethoxazole, because they inhibit sequential steps of the pathway

Question 3

Lower UTIs are called cystitis and require __________; upper UTIs (pyelonephritis) require _________.

Answer 3

nitrofurantoin or trimethoprim-sulfamethoxazole; fluoroquinolones (or AGs, or ceftriaxone if resistance is suspected)

Question 4

Antacids will decrease the bioavailability of ____________.

Answer 4

fluoroquinolones and penicillins

Question 5

The big resistance mechanism for fluoroquinolones is _________.

Answer 5

changing the target (DNA gyrase)

Question 6

Fluoroquinolones have ________ absorption and distribution.

Answer 6

good (very minimal protein binding)

Question 7

The two fluoroquinolones that are impacted by renal dysfunction are ___________.

Answer 7

ciprofloxacin and levofloxacin, but not for moxifloxacin

Question 8

The only fluoroquinolones that can kill anaerobic bacteria and atypical bacteria are _________.

Answer 8

moxifloxacin and gemifloxacin

Question 9

Levofloxacin and moxifloxacin can kill __________.

Answer 9

Gram positive cocci

Question 10

Levofloxacin is unique among the fluoroquinolones for its ability to kill _________.

Answer 10

Gram negative cocci

Question 11

Only _________ can kill Gram positive rods (within the fluoroquinolone group).

Answer 11

ciprofloxacin

Question 12

Levofloxacin and ciprofloxacin can kill _______.

Answer 12

Gram negative rods

Question 13

Overall, fluoroquinolones are ________ tolerated.

Answer 13

well (slight increase in risk of tendon rupture)

Question 14

Nitrofurantoin is toxic in those with _________.

Answer 14

renal insufficiency

Question 15

Nitrofurantoins only kill ________.

Answer 15

Gram negative bacilli (not Neisseria)

Question 16

Because they are so quickly excreted, nitrofurantoins have adverse side effects like ___________.

Answer 16

GI upset, anorexia, nephropathy with chronic use, vomiting, and diarrhea

Question 17

Metronidazole treats __________.

Answer 17

protozoa and anaerobic bacteria

Question 18

Metronidazole’s side effects include ___________.

Answer 18

nausea, headache, metallic taste, exacerbation of candidiasis infections (furry tongue), and Antabuse-like effect

Question 19

Which drug inhibits dihydrofolate reductase?

Answer 19

Trimethoprim

Question 20

Do not use sulfonamides in _________.

Answer 20

babies or pregnant women, because it raises the risk of kernicterus

Question 21

What enzyme does sulfonamide target?

Answer 21

Dihydropteroate synthetase

Question 22

The only two fluoroquinolones that can treat Pseudomonas aeruginosa are ________.

Answer 22

ciprofloxacin and levofloxacin

Question 23

Which antibiotic colors the urine brown?

Answer 23

Nitrofurantoin

Question 24

Where does metronidazole distribute to?

Answer 24

Everywhere, including CSF and bone

Question 25

What is the trade name for TMP-SMX?

Answer 25

Bactrim (trimethoprim-sulfamethoxazole)

Question 26

TMP-SMX kills ___________.

Answer 26

Gram-positive, Gram-negative, atypical, and anaerobic bacteria (including MRSA and Pseudo, except systemically)

Question 27

List the two drug interactions and the one absorption factor relevant to fluoroquinolones.

Answer 27

Theophylline/caffeine; antacids

Question 28

Can clindamycin kill Gram-negative bacteria?

Answer 28

No!