Pathogens, Vol. 12, Pages 479: Emergence of Hyper-Epidemic Clones of Enterobacterales Clinical Isolates Co-Producing KPC and Metallo-Beta-Lactamases during the COVID-19 Pandemic

Pathogens, Vol. 12, Pages 479: Emergence of Hyper-Epidemic Clones of Enterobacterales Clinical Isolates Co-Producing KPC and Metallo-Beta-Lactamases during the COVID-19 Pandemic

Pathogens doi: 10.3390/pathogens12030479

Authors: Diego Faccone Sonia A. Gomez Juan Manuel de Mendieta María Belén Sanz Mariano Echegorry Ezequiel Albornoz Celeste Lucero Paola Ceriana Alejandra Menocal Florencia Martino Denise De Belder Alejandra Corso Fernando Pasterán

Background. The global spread of carbapenemase-producing Enterobacterales has become an epidemiological risk for healthcare systems by limiting available antimicrobial treatments. The COVID-19 pandemic worsened this scenario, prompting the emergence of extremely resistant microorganisms. Methods. Between March 2020 and September 2021, the NRL confirmed 82 clinical Enterobacterales isolates harboring a combination of blaKPC and MBL genes. Molecular typing was analyzed by PFGE and MLST. Modified double-disk synergy (MDDS) tests were used for phenotypic studies. Results. Isolates were submitted from 28 hospitals located in seven provinces and Buenos Aires City, including 77 K. pneumoniae, 2 K. oxytoca, 2 C. freundii, and 1 E. coli. Almost half of K. pneumoniae isolates (n = 38; 49.4%), detected in 15 hospitals, belong to the CC307 clone. CC11 was the second clone, including 29 (37.7%) isolates (22, ST11 and 7, ST258) from five cities and 12 hospitals. Three isolates belonging to CC45 were also detected. The carbapenemase combinations observed were as follows: 55% blaKPC-2 plus blaNDM-5; 32.5% blaKPC-2 plus blaNDM-1; 5% blaKPC-3 plus blaNDM-1; 5% blaKPC-2 plus blaIMP-8; and 2.5% strain with blaKPC-2 plus blaNDM-5 plus blaOXA-163. Aztreonam/avibactam and aztreonam/relebactam were the most active combinations (100% and 91% susceptible, respectively), followed by fosfomycin (89%) and tigecycline (84%). Conclusions. The MDDS tests using ceftazidime-avibactam/EDTA and aztreonam/boronic acid disks improved phenotypic classification as dual producers. The successful high-risk clones of K. pneumoniae, such as hyper-epidemic CC307 and CC11 clones, drove the dissemination of double carbapenemase-producing isolates during the COVID-19 pandemic.