The Pharmacist’s Role in Treating Extended-Spectrum Beta-Lactamase Infections

Document Type


Publication Date



Reproduction in whole or in part without permission is prohibited. The production of a beta-lactamase—a type of bacterial enzyme—is the most common mechanism of resistance to beta-lactam antibiotics among gram-negative bacteria. Extended-spectrum beta-lactamases (ESBLs) hydrolyze most penicillins, extended-spectrum cephalosporins, and aztreonam. Infections due to ESBL-producing organisms are associated with increased mortality. Once an ESBL is detected, appropriate treatment is important in order to ensure optimal patient outcomes. Infections caused by ESBLs are challenging to treat for various reasons, including difficulty in detecting ESBL-producing organisms as well as mixed data on how to best treat these infections. The increasing worldwide prevalence of infections caused by ESBL-producing organisms highlights the importance of antimicrobial-stewardship programs to promote appropriate use of antibiotics and lessen the risk of subsequent development of resistance.