Glycopeptides Flashcards
Glycopeptide drugs
vancomycin and teicoplanin
Vancomycin administration
IV and oral for C.diff
Teicoplanin administration
not available in US
Vancomycin structure
tricyclic glycopeptide; seven membered peptide chain forming tricyclic structure and an attached disaccharide
Vancomycin MOA
inhibits cell wall synthesis by binding with cell wall precursor D-alanine-D-alanine
Vancomycin is bactericidal/bacteriostatic
slow bactericidal
Vancomycin spectrum coverage
GRAM + ONLY
dark purple: streptococcus, s. pneumoniae, viridans, MSSA, MRSA, E. faecalis
light purple: E. faecium, C. difficil (PO only)
anaerobes: only gram +
Misc: listeria monocytogenes
Vancomycin oral absorption
negligible
Vancomycin 1/2 life
4-6 hours so pretty long
Vancomycin elimination
renal
Vancomycin PO for C. difficil
is not appreciably absorbed from the GI tract
Vancomycin CSF penetration
minimal, better in inflamed
Vancomycin lung penetration
5-41%
Vancomycin adverse effects
nephrotoxicity ototoxicity red-man syndrome rash thrombophlebitis chills fever neutropenia
Red Man Syndrome + symptoms
histamine like reaction; macular rash that involves the face, neck, upper trunk, back, and arms
flushing, tingling, pruritus, tachycardia, erythema, angiodema
Red Man Syndrome begins
15-45 min after initiation of infusion
Red Man Syndrome resolves
10-60 min after termination
Red Man Syndrome is caused by
rapid IV administration
Red Man Syndrome prevention
co-administer vancomycin with anti-histamine
Vancomycin drug interactions
not really
Vancomycin resistance
enterococcus: Van A gene (d-ala-d-ala changed to d-ala-d-lactate or serine)
s. aureus: Van A gene and strains carry plasmids from VRE (d-ala-d-ala changed to d-ala-d-lactate); also VRSA
Vancomycin indications
skin and soft tissue infections bacteremia endocarditis meningitis osteomyelitis pneumonia
For which of the following infections is IV vancomycin indicated?
a. UTI from e. coli
b. infectious diarrhea from c. difficil
c. lower extremity foot ulcer from methicillin-resistant s. aureus
d. bacteremia from vancomycin resistant e. faecium
c because only gram + and c.diff is PO and VRE
Presence of Van A gene alters the peptidoglycan precursors in the bacterial cell wall in vancomycin resistant staphylococcus aureus from d-ala-dala to:
a. d-ala-d-serine
b. d-ala-d-lactate
c. d-ala-d-lys
d. d-ala-glu
b
Infusion rate for vancomycin
< 10mg/min (or close) or at least over 60 min
