Clonal diversity of Enterobacter cloacae complex of clinical and colonizing isolates harboring NDM-type carbapenemase genes in Cuba

Objectives Carbapenem-resistant Enterobacter cloacae complex (CR-ECC) is an emerging cause of nosocomial infections in Cuba. This study aimed to investigate the types of carbapenemase genes and clonal diversity of CR-ECC from clinical specimens and carriers. Methods We collected 176 clinical isolates of ECC from medical facilities in the whole country of Cuba for a six-year period (2018-2023) and 9 colonizing isolates of CR-ECC in a tertiary care hospital in Havana. Genotype was determined by the multilocus sequence typing (MLST) scheme, and beta-lactamase genes were identified by PCR and sequencing. Results Carbapenem resistance was detected in 32% of clinical isolates of ECC. bla NDM-1 was the predominant carbapenemase gene in most clinical and colonizing CR-ECC isolates, while one isolate from a carrier harbored bla NDM-5 . Among CR-ECC, ST171, ST182, ST231, and ST1833 were the most common types (4 isolates each), being assigned to E. hormaechei , and clonal complex (CC)-74 and CC114 were also dominant clonal groups. In contrast, only a few CR-ECC were detected among E. asburiae, E. kobei , and E. cloacae . Conclusions In Cuba, bla NDM-1 was the dominant carbapenemase gene in ECC and distributed to diverse lineages mostly in E. hormaechei .