Infectious disease · USMLE Step 1 and Step 2

Vancomycin song

Vancomycin - Mechanism & Toxicity, as a song. Hear the short teaser here. The full song is on YouTube and Spotify.

Vancomycin

Full song on YouTube ↗Spotify ↗

Key points in this song10

Vancomycin is a glycopeptide antibiotic that inhibits cell wall synthesis by binding to the D-Ala–D-Ala terminus of peptidoglycan precursors, preventing transglycosylation and transpeptidation.
It is the drug of choice for MRSA infections, including bacteremia, endocarditis, pneumonia, and skin/soft tissue infections caused by methicillin-resistant Staphylococcus aureus.
Vancomycin is first-line for Clostridioides difficile colitis when given orally, as oral administration produces high intraluminal concentrations with negligible systemic absorption.
"Red Man Syndrome" is a rate-related infusion reaction—not a true allergy—characterized by flushing, erythema, and pruritus of the face, neck, and upper torso, prevented by slowing the infusion rate and pre-medicating with antihistamines.
Major adverse effects include nephrotoxicity and ototoxicity (both vestibular and auditory), especially when combined with aminoglycosides, which have synergistic toxicity.
Vancomycin resistance in enterococci (VRE) occurs via substitution of D-Ala–D-Ala with D-Ala–D-Lac (VanA/VanB), reducing vancomycin binding affinity by 1,000-fold.
Therapeutic drug monitoring targets an AUC/MIC ratio of 400–600 mg·h/L for serious MRSA infections; trough-only monitoring is no longer recommended per updated ASHP/IDSA guidelines.
Vancomycin covers gram-positive organisms only—including MRSA, MRSE, and Enterococcus—and has no gram-negative activity due to inability to penetrate the outer membrane.
It is used for surgical prophylaxis in beta-lactam–allergic patients or in institutions with high MRSA prevalence, particularly for cardiac, orthopedic, and neurosurgical procedures.
Linezolid or daptomycin are alternatives when vancomycin fails or VRE is present; daptomycin is contraindicated in pneumonia because it is inactivated by pulmonary surfactant.