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Flashcards in ID 17 Deck (59):
1

Cephalosporins as a class..

beta lactase that are less susceptible to penicillinases.

2

organisms not covered by 1st-4th generation cephalosporins? exception?

LAME
Listeria
Atypicals (chlamydia, mycoplasma)
MRSA
Enterococci
Exception: ceftaroline (5th generation cephalosporin, which covers MRSA)

3

1st gen cephalosporins?

Cefazolin
Cephalexin

4

1st gen cephalosporin use?

Proteus
E coli
klebsiella

5

other use for cefazolin?

prior to surgery to prevent s aureus wound infections

6

2nd gen cephalosporins?

Cefaclor
Cefoxitin
Cefuroxime

7

2nd gen cephalosporin use?

H influenza
Enterobacter aerogenes
Neisseria
Serratia
Proteus
E coli
Klebsiella

8

3rd gen cephalosporins?

Ceftriaxone
Cefotaxime
Ceftazidime

9

ceftazidime uses..

pseudomonas

10

ceftriaxone uses..

meningitis
gonorrhea
disseminated lyme disease

11

4th generation cephalosporins...

cefepime

12

cefepime uses...

gram negatives with increased activity against pseudomonas
gram positives

13

cephalosporin AE's

1) hypersensitivity reactions
2) AIHA
3) disulfiram-like reaction
4) vitamin K deficiency
5) cross-reactivity with penicillins
6) increase nephrotoxicity of aminoglycosides

14

carbapenems

imipenem
meropenem
ertapenem
doripenem

15

imipenem as a drug and caveat

1) broad spectrum, b-lactamase resistant.
2) always administered with cilastatin

16

what is cilastatin? why do you give it with imipenem?

1) inhibitor of renal dehydropeptidase I
2) decreases inactivation of drug in renal tubules.

17

meropenem benefits

1) Decreased seizure risk
2) stable to dehydropeptidase I

18

carbapenem uses

Gram positive cocci
gram negative rods
anaerobes

19

Carbapenem AE's

1) CNS toxicity, seizure
2) skin rash
3) GI distress

20

benefits of aztreonam

1) less susceptible to beta-lactamases
2) no cross-allergenicity with penicllins

21

aztreonam mechanism

Prevents peptidoglycan cross-linking by binding to penicillin-binding protein 3.

22

aztreonam has activity against

only gram negative rods

23

aztreonam uses?

penicillin-allergic patients and those with renal insufficiency who can't tolerate ahminoglycosides.

24

vancomycin characteristics

1) bactericidal against most bacteria, except c diff
2) not susceptible to beta-lactamses

25

vancomycin uses..

*only gram positives--serious multidrug-resistant organisms like enterococcus, MRSA, C diff, S epidermidis

26

vanco AE's

1) nephrotoxic
2) ototoxic
3) thrombophlebitis
4) diffuse flushing/red man syndrome

27

how do you prevent red man syndrome?

Pretreat with antihistamines + slow infusion rate.

28

vanco resistance mechanism

amino acid modification of D-ala D-ala to D-ala D-lac

29

bactericidal protein synthesis inhibitor?

ahminoglycosides, linezolid is variable

30

peptidyl transferase function

Forms peptide bonds between adjacent amino acids using tRNAs during translation.

31

amino glycoside mechanism

1) irreversible inhibition of initiation complex through 30s binding
2) can cause misreading of mRNA
3) also block translocation

32

antibiotic used for bowel surgery?

neomycin

33

amino glycoside use?

severe gram negative rods. synergistic with beta-lactams

34

other aminoglycoside AE?

neuromuscular blockade

35

main concern for ototoxicity with ahminoglycosides?

when combined with loop diuretics

36

amino glycoside mechanism of resistance?

acetylation, phosphorylation, or adenylation

37

other things that interact with tetracyclines?

iron-containing preparations

38

tetracycline for use in renal failure?

doxycycline (fecally eliminated)

39

tetracyclines and CNS penetration?

limited

40

why are tetracyclines good at treating rickettsia and chlamydia?

can accumulate intracellularly

41

MOA of resistance to tetracyclines?

Decreased uptake or increased efflux out of bacterial cells by *plasmid encoded transport pumps.

42

chloramphenicol mechanism?

Blocks peptidyltransferase at 50S ribosomal subunit.

43

chloramphenicol uses

RMSF
Meningitis

44

Why are premies at increased risk of chloramphenicol induced aplastic anemia?

they lack UDP-glucoronyl transferase.

45

chloramphenicol MOA of resistance

*Plasmid-encoded* acetyltransferase inactivates the drug.

46

clindamycin MOA

blocks peptide transfer (*translocation) at 50S ribosomal subunit.

47

other clindamycin use...

invasive group A strep infection

48

clindamycin vs. metronidazole uses

clindamycin for anaerobes above the diaphragm, metro for below diaphragm

49

linezolid drug class

oxazolidinones

50

linezolid MOA

Inhibit protein synthesis by binding to 50s subunit and preventing formation of the initiation complex.

51

linezolid AE's

1) bone marrow suppression (especially thrombocytopenia)
2) peripheral neuropathy
3) serotonin syndrome

52

Linezolid MOA of resistance

point mutation of ribosomal RNA

53

where do macrolides bind to?

23S rRNA of 50S ribosomal subunit

54

CYP450 inhibitor macrolides?

clarithromycin and erythromycin

55

macrolide MOA of resistance?

methylation of 23s rRNA binding site prevents drug binding.

56

macrolides AE's

gastrointestinal motility issues
arrhythmia/QT prolongation
acute cholestatic hepatitis
rash
eosinophilia

57

migratory thrombophlebitis?

Vein inflammation related to recurrent thrombus formation in different locations.

58

How does migratory thrombophlebitis present?

Redness and tenderness on palpation of extremities.

59

phlebitis

vein inflammation