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Flashcards in ID 18 Deck (57):
1

Sulfonamides

Sulfamethoxazole
Sulfisoxazole
Sulfadiazine

2

Dihydropteroate synthase action

PABA + Pteridine --> Dihydropteroic acid

3

dihyrofolate reductase action

Dihydrofolic acid --> tetrahydrofolic acid

4

sulfonamide MOA

Inhibit dihyropteroate synthase

5

sulfonamide uses

nocardia
chlmaydia

6

nephrotoxic mechanism of sulfonamides

tubulointerstitial nephritis

7

sulfonamide MOA of resistance

1) Altered enzyme (bacterial dihydropteroate synthase)
2) decrease uptake
3) Increase PABA synthesis

8

Dapsone mechanism

similar to sulfonamides but structurally distinct; inhibits dihydropteroate synthase

9

trimethoprim MOA

Inhibits bacterial dihydrofolate reductase.

10

trimethoprim uses

1) UTIs
2) shigella
3) salmonella
4) pneumocystis jirovecii
5) pneumonia treatment and prophylaxis
6) toxoplasmosis prophylaxis

11

TMP AE's

1) megaloblastic anemia
2) leukopenia
3) granulocytopenia

12

fluoroquinolone mechanism

inhibit topo II and IV

13

topo II

DNA gyrase

14

fluoroquinolones AE's

1) GI upset
2) superinfection
3) skin rashes
4) headache
5) dizziness
6) leg cramps and myalgia
7) QT prolongation

15

fluoroquinolone contraindications

pregnant or nursing
kids under 18
patients taking prednisone
tendonitis or tendon rupture in people over 60

16

fluoroquinolone resistance AE

1) *chromosome encoded mutation in DNA gyrate
2) plasmid-mediated resistance
3) efflux pumps

17

daptomycin mechanism/structure

lipopeptide that disrupts cell membrane

18

daptomycin use

S aureus skin infections (especially MRSA)
bacteremia
endocarditis
VRE

19

caveat about daptomycin

can't use it for pneumonia because it binds to and is inactivated by surfactant.

20

disulfiram-like reaction presentation

severe flushing
tachycardia
hypotension

21

metronidazole uses

Guardia
Entamoeba
Trichomonas
Gardnerella vaginalis
Anaerobes (bactericides, C diff)

22

other drug that can be used as prophylaxis for m avium

rifabutin

23

m avium treatment

azithromycin or clarithromycin + ethambutol. Can add rifabutin or ciprofloxacin

24

Structure of mycobacterial cell

FA 179

25

Rifamycins

Rifampin
Rifabutin

26

rifampin/rifabutin MOA

inhibit DNA-dependent RNA polymerase

27

Why is rifampin used for leprosy?

Delays resistance to dapsone

28

Why is rifabutin used in patients with HIV infection rather than rifampin?

less CYP-450 stimulation

29

MOA of resistance to rifampin?

Mutations reduce drug binding to RNA polymerase.

30

enzyme required to activate isoniazid...

catalase peroxidase (encoded by KatG)

31

acetylation point with isoniazid

different INH half-lives in fast vs slow acetylators

32

treatment for latent TB?

INH can be used as monotherapy

33

isoniazid MOA of resistance

mutations leading to under expression of KatG

34

pyrazinamide caveats

1) prodrug (active compound = pyrazinoic acid)
2) works best at acidic pH (eg, in host phagolysosomes)

35

2nd line for TB?

streptomycin

36

streptomycin AE's

Tinnitus
Vertigo
Ataxia
Nephrotoxicity

37

strep viridan's prophylaxis

amoxicillin

38

Prophylaxis of strep pharyngitis in child with prior rheumatic fever

Benzathine penicillin G or oral penicillin V

39

Drugs covering MRSA

Vancomycin
Daptomycin
Linezolid
Tigecycline
Ceftaroline

40

Drugs covering VRE

Linezolid
streptogramins (quinupristin, dalfopristin)

41

Drugs for multidrug-resistant P aeruginosa or acinetobacter baumannii?

polymyxins B and E (colistin)

42

Squalene epoxidase action

squalene --> squalene epoxide

43

14 alpha-demethylase action

lanosterol --> ergosterol

44

caveat about administering amphotericin

Need to supplement K and Mg because of altered renal tubule permeability.

45

amphotericin AE's

1) fever/chills
2) hypotension
3) nephrotoxicity
4) arrhythmias
5) anemia
6) IV phlebitis

46

How do you decrease toxicity of amphotericin?

Hydration
Liposomal amphotericin

47

nystatin caveat

can only be used topically since too toxic

48

flucytosine MOA

Inhibits DNA and RNA biosynthesis by conversion to 5-FU by cytosine deaminase.

49

azole mechanism

Inhibit ergosterol synthesis by inhibiting CYP450 enzyme that converts lanoserol to ergosterol.

50

Fluconazole use..

Chronic suppression of cryptococcal meningitis in AIDS patients and candidal infections.

51

Azoles for use in topical fungal infections?

Clotrimazole
Miconazole

52

azoles and CYP450?

Inhibit

53

terbinafine AE's

GI upset
headaches
hepatotoxic
taste disturbance

54

echinocandins AE's

GI upset + flushing (histamine release)

55

colistin

Polymyxin E

56

polymyxins

o Coded character: Polly Nichols, as a DJ having a dance party in her kitchen: she’s pouring laundry detergent over everyone/MOA: bind to gram-negative bacterial cell membrane phospholipids and destroy the membrane by acting like a detergent. Monsterous green Ozed/used to treat severe gram-negative infections that are resistant to less toxic antimicrobials, such as multi-drug resistant pseudomonas meningitis. Her arms and legs are ice cubes + giraffe in the corner + she has stag antlers on her head (nystagmus code) + motorcycle goggles on/toxicity = numbness of the extremities + nephrotoxicity + nystagmus + blurred vision. J. Cole rapping to the left of Polly/colistin is polymixin E. Huge Giorgio armanii in left corner/also use for multidrug-resistant Acinetobacter baumannii.
o Location: Nichol’s kitchen

57

pyrimethamine MOA and usage

1) t gondii
2) inhibits dihydrofolate reductase