Open AccessMaking Antimicrobial Susceptibility Testing More Physiologically Relevant with Bicarbonate?
Author(s) -
Mariliis Hinnu,
Marta Putrinš,
Karin Kogermann,
Dirk Bumann,
Tanel Tenson
Publication year - 2022
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.02412-21
Subject(s) - bicarbonate , azithromycin , antimicrobial , efflux , drug , antibiotics , microbiology and biotechnology , pharmacology , chemistry , medicine , biology , biochemistry
Azithromycin is a clinically important drug for treating invasive salmonellosis despite poor activity in laboratory assays for MIC. Addition of the main buffer in blood, bicarbonate, has been proposed for more physiologically relevant and more predictive testing conditions. However, we show here that bicarbonate-triggered lowering of azithromycin MIC is entirely due to alkalization of insufficiently buffered media. In addition, bicarbonate is unlikely to be altering efflux pump activity.