Carbapenemase Producing Enterobacterales in Romania: Investigating the Origins

Carbapenemase-producing Enterobacterales (CPE) have emerged and spread in Romania since 2010. According to the reports of the EuSPACE (European survey of carbapenemase-producing Enterobacteriaceae) the epidemio-logical stage of the CPE expansion in Romania has shifted from sporadic occurrence in 2013 directly to inter-regional spread in 2014-2015. In this study we aimed to provide data from the timeframe when the dissemination of the carbapenemase genes in Romania began, by retrospectively analyzing CPE strains in a tertiary care university hospital. During the period of November 2012 – October 2013 we found 107 CPE (8.78%) out of 1219 non-duplicate Enterobacterales strains. 26 isolates of various Enterobacterales species carried bla_NDM-1, 83 Klebsiella pneumoniae strains were positive for bla_OXA-48-like and 2 of these co-harboured bla_NDM-1. The increased incidence of OXA-48 producing K. pneumoniae was linked to a two-peaked hospital outbreak during February and May 2013. The percentage of 24.3% of NDM-1 producers was alarming due to the diversity of involved species and the higher resistance levels to carbapenems compared with blaOXA-48-like gene carriers. Plasmid replicon typing revealed a great diversity of plasmids in NDM-1-positive strains, belonging to incompatibility groups A/C, FII, FIIk, HI2, L and M. The strong connection between certain plasmid groups and host species suggests that the transfer of broad host-range plasmids through conjugation does not play the main role in the successful spread of bla_NDM-1 among Enterobacterales species.