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Flashcards in Antibiotics Deck (82):
1

Beta Lactam Goups

Penicillins, Cephalosporins, Monobactams, Carbapenems

2

General Beta Lactam MOA

Inhibits transpeptidation

activates autolysin in cell wall

3

Beta Lactam Resistance

Beta-lactamases

Lack PBP (transpeptidase)

Autolysin mutations

4

Beta-Lactam side effects

Allergy (pen>ceph>mono)
Toxicity

5

How to most effectively use beta lactams?

Use with beta lactamase inhibitors

 

Clavulanic acid

Sulbactam

Tazobactam

6

Penicillin method of delivery

Injection

7

Acid resistant penicillins best against ______

Gram +

8

Acid resistant penicillins

Amoxicillin

PenV

Oxacillin

9

Expanded spectrum penicillins

Ampicillin

Piperacillin

Mezlocillin

Ticarcillin

10

These penicillins are resistant to beta lactamase but have _____ activity

These have lower activity

 

Nafcillin

Oxacillin

Cloxacillin

11

Common pairs for penicillin

Augmentin (Amox + CA)

Ampicillin + Sulbactam

Zosyn, Tazomed (Piperacillin + tazobactam

12

1st gen Cephs (Properties and Rx)

G +, Prophylaxis only

 

Cephalexin, Cephalothin, Cefazolin

13

2nd gen cephs (use and Rx)

Gram + and -

Used for bacterioides and not pseudomonas

Cefalcor, cefuroxime, cefoxitin

14

3rd gen ceph (use and Rx)

Gram + and -

Use for pseudomonas -- **Penetrates CNS (avoid overuse)

Ceftazidine, Cefotaxime, Ceftriaxone

15

4th gen ceph (use and Rx)

Expanded spectrum

Cefepime

16

5th gen ceph (use and Rx)

MRSA and drug-resistant Staph Pneumoniae

Cephtaroline

17

Monobactams are resistant to ______

beta lactamases

18

Monobactams used for _____

Gram (-) only

 

*no anaerobes

19

Monobactam Rx

Aztreonem

20

Carbapenems use and Rx

Broad spec for Gram + and -

Imipenem, Meropenem

21

Monobactam structure

monocyclic beta lactam ring

22

Bacitracin MOA and use

Blocks dephosphorylation of bactoprenol

 

Use synergistically for Gram +

23

Bacitracin side effects

Poor absorption

Renal toxicity

24

Glycopeptides MOA

Blocks transglycosylation and transpeptidation

 

*binds to terminal amino acid

25

Glycopeptides use

Used for Staphylococci and Enterococci

 

Not for Gram -

26

Glycopeptide resistance

Ala-Lactate at the end instead of Ala-Ala on pentapeptide

*Chromosomal genes for VanB, Plasmid genes for VanA

27

Glycopeptide Rx

Vancomycin, Telavancin

28

Cycloserine MOA

D-Ala analog

inhibits ALA Racemase

29

Cycloserine use

UTI

2nd line Tx for TB

30

Cycloserine side effects

Neurotoxic (seizures)

31

Isoniazid & Ethionamide use and MOA

Used for Mycobacterium

Inhibits pyridoxine step in myoclic acid synthesis

32

Isoniazid & Ethionamide taken with _______? Why?

Pyridoxine

Inhibits host B6

33

Ethambutol use and MOA

Used for Mycobacterium

Inhibits arabinosyl transferase (stops synth of arabinogalactan)

34

Ethambutol resistance

Rapid!

Use synergistically

35

Pyrazinamide Use and MOA

Used for Mycobacterium

Activated by Pyrazinamase from MB, Inhibits trans-translation

36

Drugs to use for confirmed Mycobacterium infection

Pyrazinamide, Ethambutol, Isoniazid & Ethionamide

+ Rifampin

37

Polymyxins MOA

Dissolve phosphatidylethanolamine in Gram - membrane

 

**also in host!

38

Polymyxins Sides

Renal toxicity

(use topically or as a last resort)

39

Polymyxins are synergistic with ______ and _______?

Bacitracin + Neosporin

40

Daptomycin structure and MOA

Cyclic lipopeptide

Dissolves in membrane to disrupt membrane potential

41

Daptomycin use and Rx

USed for Gram + cocci, MRSA

 

Cubicin

42

Daptomycin delivery

It's synergistic with _____

Given intravenously

Synergistic with Beta Lactams

43

Sulfonamides MOA and use

Inhibits PABA --> DHF -> THF -> Pyrimidines

Used for Nocardia (still susceptible)

44

SxT synergistic for ______

UTI, Salmonella, Shigellla

45

Sulfonamides Resistance

PABA overproduction

(altered enzymes)

46

Fluoroquinolones MOA and Rx

Inhibit DNA gyrase

Ciprofloxacin, Moxifloxacin

47

Fluoroquinolones Resistance

Mutated DNA gyrase

Drug exclusion

48

Fluoroquinolones solublility? How do we deal with this?

It is NOT very soluble, so it is fluorinated for UTI treatment

 

49

Fluoroquinolones use

Gram - or +

Mycobacterium (2nd line)

Pseudomonas

50

Fidaxomycin MOA and properties

Targets "switch region" of RNA Polymerase (no DNA)

 

Minimally absorbed, Narrow Spectrum

51

Fidaxomycins Rx

Dificid

52

Fidaxomycins use

Alternative to Vancomycin for VanR  C.diff

53

Rifamycin MOA

Blocks RNA polymerase elongation subunit

54

Rifamycin use and Rx

Blocks Poxvirus assembly

Used for Meningitis b/c it enters CNS

Used for Mycobacterium

Rifampin

55

Rifamycin resistance

Mutation in Beta subunit of RNApol

56

Rifamycin sides

Excreted in sweat and urine (orange)

57

Rifamycin used with _____ to do what?

Isoniazid

to delay resistance in mycobacterium

58

Metronidazole structure and MOA

Partially reduced complex with ferredoxin

breaks DNA (free radical)

59

Metronidazole use

Used against anaerobic bacteria (bacterioides, clostridium)

Antiprotozoal (Giardia)

60

Aminoglycosides MOA and Rx

Binds 30S subunit (blocks initiation-- no tRNA-fMet)

streptomycin, neomycin, gentamycin,
tobramycin, amikacin

61

Aminoglycosides resistance

Altered P12 ribosomal protein

Aminoglycosidases

Altered permeability of drug

62

Aminoglycosides uses

Synergistic with _______

Used for G- enterics

Synergistic with Cephalosporins or Penicillins

63

Tetracycline MOA and Rx

Inhibits binding of aa-tRNA to A-site of ribosome (30S subunit)

 

Doxycycline, Tigecycline

64

Tetracycline resistance

Efflux pumps

65

Tetracycline sides

Toxicity

Dizziness

Tinnitus

Fluorescent teeth

Newborn bone damage

 replace flora

66

Tetracycline uses

Rickettsia

Chlamydia

Mycoplasmas

67

Chloramphenicol MOA

Inhibits peptidyl-transferase reaction

(50S)

68

Chloramphenicol resistance

Chloramphenicol Acetyl-Transferase

(CAT)

69

Chloramphenicol uses

No longer a drug of choice because of resistance and toxicity

70

Macrolides MOA and Rx

Binds to rRNA and inhibits translocation (50S)

Clarithromyicn, Erythromycin, Azythromycin

71

Macrolide resistance

Methylation of rRNA

72

Macrolide use

Used for Gram + and some Gram -

73

Lincosamides MOA and Rx

Binds to rRNA and inhibits translocation

Clindomycin

74

Lincosamides resistance

Long term use carries risk for C. diff colonization

75

Lincosamides use

Used for anaerobes (bacterioides)

Anti-malarial

NOT to CNS

76

Nitrofurantoin MOA and use

Inhibits 30S

Use for UTI (concentrates in urine)

77

Mupirosin MOA

**Inhibits ISOLEUCINE-tRNA synthase

 

(important?)

78

Mupirosin use

Topical use for Gram+

MRSA

79

Streptogramins MOA and use

Inhibits 50S

Use for VRE and VRSA

80

Streptogramin combo

quinupristin + dalfopristin

81

Oxazolidinones MOA, use and Rx

Inhibit 50S

Use for VRE and VRSA

Linezolid

82

Methenamine MOA and use

Releases formaldehyde in acidified urine for UTI

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