Infectious Diseases: Antimicrobials Flashcards Preview

Small Animal Internal Medicine > Infectious Diseases: Antimicrobials > Flashcards

Flashcards in Infectious Diseases: Antimicrobials Deck (49):
1

What is the MOA of sulfonamides?

Synergistic inhibition of folate metabolism, resulting in inhibition of purine (DNA/RNA) synthesis

2

What does Trimethoprim inhibit?

Dihydrofolate reductase

3

What are sulfonamides a competitive inhibitor of?

Pteridin synthase

4

What is the spectrum of sulfonamides?

Broad spectrum (Gram + and - especially Nocardia)

5

In which tissue do sulfonamides have great penetration?

Prostate

6

What are the adverse effects of sulfonamides? (5)

1. Immune-mediated thrombocytopenia

2. Hepatotoxicity

3. Bone marrow suppression

4. KCS

5. Polyarthritis

7

What is TMS?

Trimethroprim-sulfonamide

8

Is TMS bacteriostatic or bactericidal?

Bactericidal

9

What 3 tests would you use to monitor adverse effects associated with sulfonamides?

1. Shirmer tear test

2. Liver panel

3. CBC

10

Name 4 aminoglycosides...

1. Neomycin

2. Tobramycin

3. Amikacin

4. Gentamicin

11

What is the MOA of aminoglycosides?

Inhibit protein synthesis by binding to 30S ribosomal subunit

12

Against which class of bacteria do aminoglycosides have excellent activity?

Gram -

13

Which class of bacteria have intrinsic resistance to aminoglycosides?

Anaerobes

14

Because aminoglycosides have poor oral absorption, how can you administer them?

SQ, IM, IV

15

What are the adverse effects of aminoglycosides?

1. Ototoxicity

2. Nephrotoxicity

16

What is the MOA of chloramphenicol?

Inhibition of protein synthesis by binding 50S ribosomal subunit

17

What is the spectrum of chloramphenicol?

Broad (+/-) and anaerobes

18

What are the 3 adverse effects associated with chloramphenicol?

1. Irreversible aplastic anemia

2. Reversible bone marrow suppression

3. GI effects

19

Name 3 tetracyclines....

1. Doxycycline

2. Tetracycline

3. Minocycline

20

What is the MOA of the tetracycline?

Inhibition of protein synthesis by binding the 30S ribosomal subunit

21

What is the spectrum of tetras?

1. Gram +

2. Some gram -

3. Intracellular bacteria

22

What are the adverse effects associated with tetras?

1. Teeth discoloration (tetracycline specifically)

2. Hepatotoxicity

3. Vomiting

4. Esophageal strictures

23

Name a lincosamide...

Clindamycin

24

Name a macrolide...

1. Azithromycin

2. Clarithromycin

3. Tylosin

25

What is the MOA of the Lincosamides and Macrolides?

Inhibit protein synthesis by binding to 50S ribosomal subunit

26

Where do Lincosamides achieve high concentrations?

Leukocytes

27

Where do Macrolides achieve high concentrations?

Tissues

28

What is the spectrum of lincosamides?

1. Gm +

2. Anaerobes

3. Protozoa

29

What are the AE associated with lincosamides?

Esophagitis in cats

30

What is the spectrum of macrolides?

1. Gm +

2. Some gm -

3. Mycobacterium

31

What is the AE associated with macrolides?

Antibiotic-responsive diarrhea

32

What is the MOA of the azoles?

Interfere with ergosterol synthesis inhibition of 14a-demethylase

33

Are the azoles fungistatic or fungicidal?

Fungistatic

34

Name 2 classes of azoles...

1. Imidazoles

2. Triazoles

35

Name 3 imidazoles...

1. Ketoconazole

2. Clotrimazole

3. Enilconazole

36

Name 4 triazoles...

1. Itraconazole

2. Fluconazole

3. Voriconazole

4. Posaconazole

37

Which has good bioavailability, the imidazoles or the triazoles?

Triazoles (the imidazoles have poor bioavailability and should only be used topically)

38

What are the 4 adverse effects associated with azoles?

1. Hepatitis

2. Inhibition of mammalian p450

3. Teratogenic

4. Ulcerative lesions in dogs with itraconazole

39

Which azole is the most hepatotoxic?

Ketoconazole

40

What are the 2 MOA of amphotericin B?

1. Causes pores in the cell membrane by binding to sterols

2. Macrophage activation

41

Is amphotericin B fungistatic or fungicidal?

Fungistatic at low doses

Fungicidal at high doses

42

What are the adverse effects associated with amphotericin B?

Nephrotoxicity

43

What is the MOA of 5-flucytosine?

Interferes with DNA replication

44

What is 5-flucytosine?

A fluorinated pyrimidine

45

What organisms is 5-flucytosine effective against?

1. Cryptococcus

2. Candida

46

What are the adverse effects associated with 5-flucytosine?

1. Cutaneous drug eruption in dogs

2. Myelosuppression

3. Resistance

47

How can you prevent resistance to 5-flucytosine?

NEVER USE ALONE: Always combine with another anti-fungal drug.

48

What is the MOA of terbinafine?

Inhibition of squalene epoxidase --> intracellular accumulation of squalene --> cell lysis

49

What is the adverse effect associated with terbinafine in the cat?

Facial pruritis