A patient with a penicillin allergy develops endocarditis due to MRSA. The antibiotic of choice, which inhibits cell wall synthesis by a mechanism distinct from beta-lactams, is:
- A Linezolid
- B Clindamycin
- C Vancomycin ✓
- D Daptomycin
Correct answer: C. Vancomycin
Explanation
Vancomycin inhibits cell wall synthesis by binding to the D-Ala-D-Ala terminus of peptidoglycan precursors, blocking transglycosylation — a mechanism entirely different from beta-lactams which inhibit PBPs. It is bactericidal for MRSA endocarditis, particularly right-sided disease. Linezolid inhibits protein synthesis (30S-50S ribosomal joining); clindamycin inhibits 50S; daptomycin disrupts membrane potential (not cell wall synthesis per se).
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.