Molecular characterization of carbapenem-resistant Pseudomonas aeruginosa from four hospitals of VenezuelaWe analyzed 17 strains of Pseudomonas aeruginosa resistant to carbapenems isolated in four hospitals in eastern and southern Venezuela collected between 2007 and 2010.Combined disk method showed production of metallo-β-lactamases (MBLs) in all strains.PCR and sequencing of genes encoding IMP, VIM and SPM metallo-β-lactamase families confirmed the presence of VIM-2 MBL in all strains.Pulsed field gel electrophoresis classified the strains into three similarity groups.The largest group, group A included 13 strains with over 83% similarity between them and was found in four hospitals.Two strains of Cumana hospital formed the group B and other two the Group C with similitary of 73% and 65% respectively with Group A. These results confirmed that hospitals in eastern and southern Venezuela, circulating strains of P. aeruginosa producing VIM-2 type MBLs with a common clonal origin.On the other hand, carbapenem-resistant P. aeruginosa circulating in Cumana city hospital had polyclonal origin.