Ability of Bicarbonate Supplementation To Sensitize Selected Methicillin-Resistant <i>Staphylococcus aureus</i> Strains to β-Lactam Antibiotics in an <i>Ex Vivo</i> Simulated Endocardial Vegetation Model

Abstract

Supplementation of standard growth media (cation-adjusted Mueller-Hinton Broth [CAMHB]) with bicarbonate (NaHCO 3 ) increases β-lactam susceptibility of selected methicillin-resistant Staphylococcus aureus (MRSA) strains (“NaHCO 3 responsive”). This “sensitization” phenomenon translated to enhanced β-lactam efficacy in a rabbit model of endocarditis.