Fosfomycin

Question 1

Fosfomycin is produced

Answer 1

synthetically

Question 2

Researchers found that Fosfomycin needs ___added to exhibit full antimicrobial activity

Answer 2

glucose-6-phosphate

Question 3

Fosfomycin structure is

Answer 3

small and easily forms salts

Question 4

Fosfomycin has ___ bioavailability

Answer 4

low

Question 5

Fosfomycin is mostly used for

Answer 5

UTI

Question 6

Fosfomycin MOA

Answer 6

1. enters the cell through 2 active transport systems GLpT and UhpT
2. once inside it reversibly blocks bacterial cell wall synthesis

Question 7

Fosfomycin acts as an analog of

Answer 7

phosphoenolpyruvate (PEP)

Question 8

Fosfomycin inhibits

Answer 8

initial peptidoglycan synthesis step triggered by MurA

Question 9

Fosfomycin is bactericidal/bacteriostatic

Answer 9

bactericidal

Question 10

Fosfomycin oral absorption

Answer 10

sucks

Question 11

Fosfomycin 1/2 life

Answer 11

short

Question 12

Fosfomycin elimination

Answer 12

renal

Question 13

Fosfomycin has ___ protein binding

Answer 13

negligible

Question 14

Fosfomycin is only available as

Answer 14

oral agent

Question 15

Fosfomycin spectrum coverage

Answer 15

dark purple: MSSA, MRSA, e. faecium, e. faecalis

dark red: e.coli, klebsiella, p.mirabilis, enterobacter, citrobacter, serratia

light red: p.aeruginosa

Misc: salmonella, shigella, listeria, aero coccus, h. pylori

Question 16

Fosfomycin is inactive against

Answer 16

stenotrophomonas, burkholderia, s. saprophyticus

Question 17

Fosfomycin mechanism of resistance

Answer 17

mutation at the murA gene cause altered binding

over expression of enopyruvyl transferase circumventing the activity of Fosfomycin

mutations in transport system

modifying enzymes FosA, FosB, FosC

Question 18

Fosfomycin adverse effects

Answer 18

well tolerated
GI: diarrhea, nausea
GU: vaginitis
hypersensitivity is rare

Question 19

Fosfomycin drug interactions

Answer 19

drugs that stimulate motility like metoclopramide, decrease absorption

Question 20

Fosfomycin indications

Answer 20

uncomplicated acute cystitis
complicated cystitis
prophylaxis

Question 21

Fosfomycin dosing for uncomplicated acute cystitis

Answer 21

3g dose (powder to mix with water) x 1 dose

Question 22

Fosfomycin dosing for complicated cystitis

Answer 22

may repeat dose every 48 hours for 3 doses

Question 23

Fosfomycin prophylactic dose

Answer 23

recurrent UTI: 3 g q10days

Question 24

Fosfomycin is ____($$$$$)

Answer 24

expensive!!