Dissemination of Carbapenem-Resistance among Multidrug Resistant carrying Metallo-Beta-Lactamase Genes, including the Novel Gene in Thailand.

BACKGROUND

is considered as one of the most emerging threats in this century. Serious infections caused by this pathogen are often treated by carbapenems which are the last resource of antibiotics. Metallo-beta-lactamases (MBLs) production is one of the most important carbepenem resistance mechanisms and is usually related with nosocomial infections caused by . This study was aimed to determine the prevalence of MBL genes and distribution pattern of MBLs producing strains in Thailand.

MATERIALS AND METHODS

Specific primers were designed to detect MBL genes including IMP-, VIM-, and NDM-type MBL genes. Multilocus sequence typing method was used to determine the dissemination pattern of carbapenem-resistance among multidrug-resistant (CR-MDR) .

RESULTS

A total of 153 clinical isolates were characterized as CR-MDR. Among those, 31 clinical isolates (20.3%) presented metallo-beta-lactamase genes which could be divided into VIM-type (14 strains) and IMP-type (17 strains). , , , and genes were detected. Moreover, a novel IMP-type MBL, was discovered and it was demonstrated to be the unique group of MBLs in Thailand. It was of interest that ST235 was the major ST type in Thailand followed by ST964 and ST111 and ST235 was detected in both MBL harboring and non-MBL harboring strains.

CONCLUSION

This study reported the dissemination of MBL gene including novel MBL, . This study was also demonstrated major ST of which was ST235, followed by ST964 and ST111. Moreover, it is also the first report on many STs in Thailand: ST273, ST292, ST621, ST1584, and ST1816 which emphasized the dissemination trait difference of MBLs harboring in Thailand.