Abstract
BackgroundblaVIM-2 harboring Pseudomonas aeruginosa has been reported worldwide and considered as the most prevalent metallo-β-lactamase after NDM which are found horizontally transferable and mostly associated with integron gene cassettes. The present study investigates the genetic background, transmission dynamics as well as stability of blaVIM-2 in clinical isolates of P. aeruginosa harbor blaNDM-1 as well which were collected from October 2012 to September 2013.MethodsTwo P. aeruginosa strains harboring blaVIM-2 along with blaNDM-1 were isolated from Silchar Medical College and Hospital, India. Genetic environment of these resistance determinants was determined and transferability was checked by transformation and conjugation assay which was further confirmed by Southern hybridization. Replicon typing was performed to determine the incompatibility group of the resistant plasmid and their stability was checked by serial passage method. Antimicrobial susceptibility pattern of the isolates was determined and their clonal relatedness was checked by pulsed field gel electrophoresis.ResultsblaVIM-2 was found to be horizontally transferable through an Inc F type plasmid of approximately 30 kb in size. blaVIM-2 was found to be associated with integron gene cassette and was flanked by two different types of cassette arrays. Both the isolates were co-harboring blaNDM-1 which was carried within Inc N type of plasmid with an approximate 24 kb in size and associated with ISAba125 in their upstream region. Reduced susceptibility rate as well as high MIC range was observed in case of wild strains and transformants carrying blaVIM-2 and blaNDM-1.ConclusionsThe detection of this co-existence of multiple carbapenem resistance genes in this part of world is worrisome and further investigation is required in order to trace the source and to initiate proper treatment option.
Highlights
BlaVIM-2 harboring Pseudomonas aeruginosa has been reported worldwide and considered as the most prevalent metallo-β-lactamase after New Delhi metallo-β-lactamase (NDM) which are found horizontally transferable and mostly associated with integron gene cassettes
The present study describes genetic background, transmission dynamics as well as stability of blaVIM-2 and blaNDM-1 in clinical isolates of P. aeruginosa
Molecular characterization of blaVIM and blaNDM gene polymerase chain reaction (PCR) assay was performed for detection of blaVIM as described earlier [8] as well as other metallo-β-lactamase gene [4] and amplified products were further sequenced to confirm the presence of resistant gene
Summary
BlaVIM-2 harboring Pseudomonas aeruginosa has been reported worldwide and considered as the most prevalent metallo-β-lactamase after NDM which are found horizontally transferable and mostly associated with integron gene cassettes. The present study investigates the genetic background, transmission dynamics as well as stability of blaVIM-2 in clinical isolates of P. aeruginosa harbor blaNDM-1 as well which were collected from October 2012 to September 2013. Carbapenems are considered as the last drug of choice for most of the serious infections caused by Gram negative bacteria, but due to the prevalence of multidrug resistant organisms these lifesaving drugs were compromised in treating the patients with severe illness. The present study describes genetic background, transmission dynamics as well as stability of blaVIM-2 and blaNDM-1 in clinical isolates of P. aeruginosa. The presence of mobile element like ISCR in each strain was determined by performing PCR using primers ISCR F (5′RNSBATAGGAADWWNAAHMNV-3′) and ISCR R (5′-BNKDTTNWWHTTCCTATVSNY-3′)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
