Glycopeptides

Question 1

Drugs

Answer 1

Vancomycin (use with MRSA and PRSP)
Teicoplanin
Dalbavancin
Telavancin
Oritavancin

Question 2

Vanco MoA

Answer 2

Inhibits cell wall synthesis (different site than B-lactams)

Binds to D-alanyl-D-alanine portion of cell wall to prevent cross-linking

Time-dependent bactericidal activity; slowly kills bacteria (static against entero)

Question 3

Vanco MoR

Answer 3

Resistance in VRE and VRSA from modification of D-alanyl-D-alanine binding site of peptidoglycan

VanA, vanB, vanC phenotypes

VISA (vanco intermediate s. aureus) has thickened cell wall, intermediate susceptibility

Question 4

Vanco Pharmacology

Answer 4

Time-dependent bactericidal activity

Oral is no good (except for colitis), must use IV therapy for systemic infections

Widely distributed into body tissues, variable penetration into CSF (even with inflamed meninges)

TAKES 1 HR to distribute from plasma into tissue compartment

Eliminated unchanged by kidney, NOT removed by hemodialysis

Question 5

Vanco Adverse Effects

Answer 5

Red-Man Syndrome: flushing, pruritis, erythematous rash from high RATE of IV infusion, resolves spontaneously after discontinuation

Nephrotoxicity and Ototoxicity

Rash, neutropenia/thrombocytopenia, thrombophlebitis, interstitial nephritis

Question 6

Dalbavancin

Answer 6

2nd generation glycopeptide
Good for MRSA, VISA, VRE (vanB and vanC), MRSE, strepto, bacillus, listeria, corynebacter

Similar MoA to vanco, but more potent and cidal

Once/week dosing, IV only

Anaphylaxis, skin rxn, red man infusion, increased ALT, hematologic, head aches

Question 7

Telavancin

Answer 7

MRSA and gram+s

Complicated SSSI, hospital acquired pneumonia, ventilatorAP (s.aureus)

AE: nausea/vomiting/constipation, headache, more renal toxicity than vanco

Be careful with pregnant women

Question 8

Oritavancin

Answer 8

Semisynthetic glycopeptide for gram+s

MSSA, MRSA, entercoccus, strep, B.antracis

Disrupts cell membrane