Genetic Diversity of KPC-ProducingEscherichia coli, Klebsiella oxytoca, Serratia marcescens, andCitrobacter freundiiIsolates from Argentina

Abstract

The predominance of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae was caused by the spread of ST258 clone. In Latin America, KPC was reported in 2006, with the isolation of genetically unrelated K. pneumoniae in Colombia. Since then, the expansion of bla in either K. pneumoniae ST258 or other Enterobacteriaceae (ETB) species was increasingly reported. In this study, we characterized 89 KPC-producing Escherichia coli, Klebsiella oxytoca, Serratia marcescens, and Citrobacter freundii that were received between 2010 and 2014. The results revealed that all isolates harbored bla. Moreover, the dissemination of KPC by non-K. pneumoniae was mainly caused by the dispersion of ETB mostly genetically unrelated. E. coli is a community pathogen that may serve as the vehicle for the spread of KPC into community settings. Recently, KPC was detected in E. coli ST131, an international epidemic and multidrug-resistant clone. We found that 5/29 KPC-producing E. coli belonged to ST131 and four were bla producers. The detection of bla in ST131 should be closely monitored to prevent further dissemination. The bla is generally located within Tn4401 transposon capable of mobilization through transposition found in plasmids in ST258. Less is known about the diversity of bla genetic elements that disseminate horizontally among other species of ETB. We found that 16/29 E. coli and 2/18 S. marcescens harbored bla in Tn4401a. In 71 isolates, bla was located amidst diverse Tn3-derived genetic elements bearing non-Tn4401 structure. Further studies on the plasmids that encode bla in these clinical isolates may provide additional insight into its transmission mechanisms.

Plasmidic resistance to colistin mediated by mcr-1 gene in Escherichia coli clinical isolates in Argentina: A retrospective study, 2012–2018

“…In Argentina, bla KPC-2 is the main carbapenemase among Enterobacterales; however, during recent years, an increase in detection of bla NDM-1 has been observed, especially in Providencia spp. (14,18,24,27). In the present collection, 5 carbapenemase-producing mcr-1-positive E. coli isolates were detected, yielding an extensively drug-resistance phenotype for which the unique therapeutic option was tigecycline.…”

“…A degenerated primer, MCR-1.5-F, with a mismatch at the third base from the 3´extreme was designed to increase the PCR specificity ( Table 1). The genetic relatedness between the isolates was evaluated by XbaI-digested pulsed-field gel electrophoresis (PFGE) using a Chef-DR ® III System (Bio-Rad TM , Hercules, CA, United States) as previously reported (24). DNA fragments were resolved in 1% agarose gel applying a switch time of 2.4 to 54.2 seconds during 20 hr at 14°C.…”

Characterization of Carbapenemase-Producing Klebsiella oxytoca in Spain, 2016–2017

“…In the three isolates producing class D carbapenemases, bla OXA-48 was carried on IncL plasmids, one of ϳ63 kb (two isolates) almost identical to plasmid pOXA-48 (GenBank accession number NZ_CP018342.1; average identity, Ͼ95%; average coverage percentage, 99.8%) ( Fig. S3) and another of ϳ48 kb (one isolate) highly similar to the plasmid with GenBank accession number NZ_CP018694.1 (average identity, Ͼ95%; average coverage percentage, 94.3%), reconstructed with a low number of contigs (8,7, and 3 respectively) ( Table 2). In all three isolates, bla OXA-48 was flanked by IS1999 sequences.…”

“…Klebsiella oxytoca has been recognized as an opportunistic pathogen causing health care-associated infections, such as urinary and respiratory tract infections and sepsis, primarily in immunocompromised and debilitated patients admitted to intensive care units. However, little information about carbapenemase-producing (CP) K. oxytoca is available, since only a few individual cases or nosocomial outbreaks have been reported (6)(7)(8)(9).…”

Comparative analysis of >i<Klebsiella pneumoniae>/i< belonging to the endemic high-risk clonal group CG258

“…pneumoniae (CUZON;NORDMANN, 2011;CHERUVANKY et al, 2017), other studies have increasingly demonstrated the frequency of the non-Tn4401 (NTEKPC), also associated with the dispersion of this resistance gene , ARAÚJO et al, 2018a, DE BELDER et al, 2018MANAGEIRO et al, 2018;. These elements were first described in 2006 in China (SHEN et al, 2009), and were thereafter reported in South America (Brazil and Argentina) (GOMEZ et al, 2011.…”