2017 Volume 66 Issue 6 Pages 649-655
Drug-resistant gram-negative bacilli have recently emerged as a major problem worldwide. The production of extended-spectrum β-lactamases (ESBLs) is an important resistance mechanism of pathogenic bacteria, which impedes the treatment of infections caused by gram-negative bacilli with drugs. Therefore, there is a compelling need to develop rapid detection methods for ESBL-producing bacteria. Herein, we evaluated the performance of a drug-susceptibility measurement instrument, DPS192iX (Eiken Chemical Co., Ltd.) for the rapid detection of ESBL-producing bacteria using various β-lactamase-producing Enterobacteriaceae strains. Seventy-one β-lactamase-producing strains were used for the analysis. The concordance between detection rates (within +/−1 difference in each tube) was >94% for all test agents compared with those obtained by the conventional method. The detection rates of 28 ESBL-producing strains were high: 96% for CTX, 68% for CAZ, 93% for CPR, and 96% for CPDX at 18 hours and 75% for CTX and 96% for CPDX at 5 hours. At 18 hours, all the ESBL-producing strains were detected using at least one of the agents. The results obtained should, however, be carefully examined because they depend on the genotypes of the ESBL-producing strains. Nevertheless, the drug susceptibilities of various β-lactamase-producing Enterobacteriaceae strains can be determined with high accuracy by using DPS192iX in routine tests. In addition, the ESBL-producing strains can be rapidly detected by using DPS192iX. In conclusion, the findings of this study demonstrate that the use of DPS192iX could ensure the proper use of antibiotics and thus contribute to the development of control measures against hospital infections caused by drug-resistant bacteria.