625. Genomic Epidemiology of Carbapenem-Resistant Enterobacteriaceae from Colombia: A Prospective Multicenter Study

Abstract

Abstract Background Carbapenem-resistant Enterobacteriaceae (CRE) is a serious public health threat. A major epidemic of carbapenemase-producing Klebsiella pneumoniae has occurred in Colombia through complex mechanisms of blaKPC dissemination. In the framework of a prospective, observational cohort study (CRACKLE-2), we aimed to characterize the genomic epidemiology of CRE circulating in Colombia. Methods We performed whole-genome sequencing of 52 isolates collected from the same number of patients (July 2017–April 2018) in 5 Colombian hospitals. Species confirmation and sequence type were determined using Strain Seeker and MLST database. Resistance genes were detected using ResFinder and CARD databases. Phylogenetic reconstruction included additional 108 isolates of carbapenem-resistant K. pneumoniae from a previous study. Results K. pneumoniae (36%), Escherichia coli (17%), and Enterobacter cloacae complex(17%) were the most frequent species. Genes conferring resistance to carbapenems were detected in 93% of isolates. blaKPC-2/3,blaNDM-1 andblaVIM-2/24 were identified in 81%, 15%, and 5% of isolates, respectively. Phylogenetic reconstructions of K. pneumoniae showed that clonal group 258 (CG258) were the predominant genetic lineage (Figure 1). Among CG258, ST11 was the most common comprising ca. 26% of isolates. Of note, ST11 had been extremely rare in previous surveillance studies in Colombia. The non-CG258 were from 9 different STs and exhibited high genomic diversity. Among E. coli isolates 33% belonged to the high-risk clone ST131 harboring blaKPC-2 and we detected both blaKPC-2 and blaVIM-24 in 1 E. coli ST131 isolate. ST510 E. cloacae complex harboring blaKPC-2 was the most common (44%) lineage. Conclusion K. pneumoniae and E. coli are the most frequent CRE isolated from patients in Colombian hospitals. Dissemination of blaKPC through horizontal gene transfer to several species of Enterobacteriaceae continues to be a common mechanism of spread. Although KPC continues to be the most common carbapenemase, a rise in high-risk clonal lineages harboring metallo-carbapenemases, in particular NDM-1 is worrisome. Our results indicate emergence of virulent genetic lineages of K. pneumoniae ST11 and E. coli ST131 carrying carbapenemases in Colombia. Disclosures All authors: No reported disclosures.