Carbapenemase-producing Pseudomonas aeruginosa in Spain: interregional dissemination of the high risk-clones ST175 and ST244 carrying blaVIM-2, blaVIM-1, blaIMP-8, blaVIM-20 and blaKPC-2

Abstract Carbapenemase-producing (CP) Pseudomonas aeruginosa has been rare in comparison with mutation-driven carbapenem-resistance, but this situation may be changing; we characterized a collection of CP P. aeruginosa isolates. In 2016, 232 unduplicated carbapenem-resistant P. aeruginosa isolates were submitted to the Spanish antibiotic reference laboratory of which 71 (30.6%) carried carbapenemases genes and were further analysed by whole genome sequencing (WGS). Of the 71 CP P. aeruginosa, 39 (54.9%) carried blaVIM-2, 14 (19.7%) blaVIM-1, 8 (11.3%) blaIMP-8, 6 (8.5%) blaVIM-20, 2 (2.8%) blaVIM-2 plus blaKPC-2, one (1.4%) blaIMP-13 and one (1.4%) blaVIM-1 plus blaIMP-18. Four STs (ST175, ST244, ST815 and ST155) encompassed 83.1% of the 71 CP P. aeruginosa; ST175 was detected in hospitals from seven provinces. Using cgMLST, 4 clusters were detected: Clusters 1 included nine ST815/VIM-2 isolates; Cluster 2 included five ST175/VIM-2 isolates; Cluster 3 included seven ST244 isolates (five VIM-2 and two VIM-2 plus KPC-2); and Cluster 4 included 11 ST175 isolates (seven VIM-2 and four IMP-8). The average number of acquired resistance genes was significantly higher in the blaVIM-1-carying isolates (7.1 ± 0.94) than in the blaVIM-2-carrying isolates (average of 4.5± 0.20). CP P. aeruginosa isolates are spreading in Spain mainly due to the dissemination of high risk clones such as ST175 and ST244 producing VIM and IMP carbapenemases. Emergence of CP P. aeruginosa is a cause of clinical and epidemiological concern.