In vitro activities of eravacycline against clinical bacterial isolates: a multicenter study in Guangdong, China

The MIC₅₀ and MIC₉₀ (mg/L) of eravacycline were 0.12 and 1 for S. aureus, 0.06 and 0.12 for <i>E. faecalis</i>, 0.06 and 0.5 for <i>E. faecium</i>, 0.25 and 0.5 for <i>E. coli</i>, 0.5 and 2 for <i>K. pneumoniae</i>, and 0.25 and 2 for <i>A. baumannii</i>. Based on the FDA and EUCAST breakpoints, the susceptibility of eravacycline against <i>S. aureus</i> was 46.03% vs. 83.33%, 56.90% vs. 94.93% against <i>E. faecalis</i>, and 62.07% vs. 79.31% in <i>E. faecium</i>. The susceptibility rates of <i>E. coli</i> and <i>K. pneumoniae</i> were 90.37% and 58.09, respectively. To evaluate the performance between the broth microdilution test (BMD) and ETEST methods, we compared essential agreement (EA), categorical agreement (CA), very major error (VME), and major error (ME). The results demonstrated that compared with BMD, eravacycline measured by ETEST had higher VME and ME referring to FDA breakpoints than EUCAST breakpoints in the Gram-positive isolates. Since there were no intermediate breakpoints for the eravacycline, the MIC values measured by the ETEST method might result in lower CA and higher VME and ME. This study provides MIC values of eravacycline against Gram-positive and Gram-negative pathogens in four hospitals in Guangdong Province, and eravacycline is an effective therapeutic candidate for common bacteria.