Glycopeptides

Question 1

What are the 4 glycopeptides that are clinically in use?

Answer 1

• Vancomycin
• Telavancin
• Dalbavancin
• Oritavancin

Question 2

(T/F) - Vancomycin has activity against all gram (+) organisms

Answer 2

TRUE

Question 3

(T/F) - Vancomycin has become resistant to many enterococci especially E. faecium

Answer 3

TRUE

Question 4

What is another name of vancomycin resistant to enterococci?

Answer 4

Vancomycin-resistant enterococci (VRE)

Question 5

(T/F) - Streptococci has learned to become resistant to vancomycin

Answer 5

FALSE - not streptococci but staphylococci has but is rare

Question 6

Which glycopeptides are long-acting glycopeptides that can be taken once IV for a 2-week course but is very expensive?

Answer 6

• Dalbavancin

- Oritavancin

Question 7

What is the MOA of glycopeptides?

Answer 7

• Inhibits cell wall synthesis binding to the D-alanine-D-alanine residues of peptide cell wall precursors
• Bactericidal against nearly all gram (+) bacteria

Question 8

Vancomycin should be used in combination with which other medication against enterococci?

Answer 8

Aminoglycosides because of its bacteriostatic effect

Question 9

What is the mechanism of resistance of glycopeptides?

Answer 9

Mutation of D-alanine-D-alanine binding site such that vancomycin cannot bind to the cell wall precursors

Question 10

Which glycopeptide can be given IV and PO?

Answer 10

Vancomycin

Question 11

Glycopeptides have a good spectrum in which bacteria?

Answer 11

• MRSA
• MSSA
• Streptococci
• C. difficile

Question 12

Which glycopeptide can only be given for C. difficile?

Answer 12

Vancomycin PO

Question 13

What adverse events can occur with vancomycin?

Answer 13

• Ototoxicity
• Nephrotoxicity
• Red man syndrome

Question 14

How can nephrotoxicity occur with vancomycin?

Answer 14

By giving the patient high doses

Question 15

What are symptoms of red man syndrome with the use of vancomycin?

Answer 15

• Warmth
• Flushed
• Hypotensive may occur

Question 16

How can red man syndrome be prevented with the use of vancomycin?

Answer 16

• Slow the infusion rate AND/OR

- Antihistamine given prior to infusion

Question 17

(T/F) - Red man syndrome is a true allergy

Answer 17

FALSE - it’s not

Question 18

What adverse events can occur with telavancin?

Answer 18

• Nephrotoxicity
• Foamy urine
• Taste disturbance
• Red man syndrome
• QT prolongation

Question 19

Telavancin is contraindicated in which patients?

Answer 19

Pregnant patients

Question 20

What adverse events can occur with dalbavancin?

Answer 20

• Infusion reactions
• AST elevations
• nausea, HA, diarrhea

Question 21

What adverse events can occur with oritavancin?

Answer 21

• Infusion reactions
• HA
• N/V/D
• Limb and SQ abscesses

Question 22

What drug can interact with oritavancin?

Answer 22

Warfarin; warfarin can increase by oritavancin falsely prolonging aPTT for up to 48 hours and PT/INR for up 24 hrs

Question 23

How can you determine that glycopeptides are not being eliminated too quickly?

Answer 23

By checking trough levels

Question 24

(T/F) - IV vancomycin can also be used for C. difficile but it’s best to use PO vancomycin

Answer 24

FALSE - only PO vancomycin is used for C. difficile; IV vancomycin cannot reach the colon

Question 25

(T/F) - Vancomycin can kill MSSA infections as quickly as beta-lactams

Answer 25

FALSE - Vancomycin cannot kill MSSA infections as quickly as beta-lactams; use nafcillin/oxacillin or cefazolin for MSSA infections

Question 26

What is the DOC for vancomycin?

Answer 26

- MRSA infections | - Empiric use of MRSA infections (such as nosocomial infections)

Question 27

Vancomycin is also utilized for what other indications?

Answer 27

- Gram (+) infections when a patient has a severe beta-lactam allergy

Question 28

What is telavancin FDA-approved of?

Answer 28

- Complicated skin/skin structure infections | - Hospital acquired pneumonia

Question 29

What is dalbavancin and oritavancin mainly utilized for?

Answer 29

- Acute bacterial skin/skin structure infections

Question 30

(T/F) - These drugs are active against VRE

Answer 30

FALSE - they are not active against VRE

Question 31

What should you always make sure when monitoring vancomycin?

Answer 31

That the trough concentration was drawn correctly