Evaluation of the usefulness of selected methods for the detection of carbapenemases in Klebsiella strains

Abstract

<jats:p> <jats:bold>Introduction.</jats:bold> <jats:italic> <jats:named-content content-type="genus"> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://doi.org/10.1601/nm.3202" xlink:type="simple">Klebsiella</jats:ext-link> </jats:named-content> </jats:italic> rods, belonging to the family <jats:italic> <jats:named-content content-type="family"> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://doi.org/10.1601/nm.3091" xlink:type="simple">Enterobacteriaceae</jats:ext-link> </jats:named-content> </jats:italic>, are generally opportunistic pathogens commonly associated with nosocomial infections, especially in intensive care units. Interestingly, strains of this genus also show multi-drug resistance. In recent years, multiple studies have indicated that the prevalence of carbapenem resistance has increased rapidly among <jats:italic> <jats:named-content content-type="genus"> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://doi.org/10.1601/nm.3202" xlink:type="simple">Klebsiella</jats:ext-link> </jats:named-content> </jats:italic> representatives.</jats:p> <jats:p> <jats:bold>Aim.</jats:bold> The aim of this study was to assess the usefulness of selected phenotypic and genotypic methods for the detection of the most important carbapenemases in <jats:italic> <jats:named-content content-type="genus"> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://doi.org/10.1601/nm.3202" xlink:type="simple">Klebsiella</jats:ext-link> </jats:named-content> </jats:italic> strains.</jats:p> <jats:p> <jats:bold>Methodology.</jats:bold> The study involved 51 <jats:italic> <jats:named-content content-type="genus"> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://doi.org/10.1601/nm.3202" xlink:type="simple">Klebsiella</jats:ext-link> </jats:named-content> </jats:italic> strains. The ability to produce carbapenemases was determined by phenotypic methods (double disc synergy test, test with four discs and three inhibitors, CarbaNP test, culture on chromogenic medium, panels of automatic method – Phoenix, CIM test and modified Hodge test). The potential for carbapenemase synthesis was also evaluated using real-time PCR, detecting <jats:italic>bla</jats:italic> <jats:sub>VIM/IMP</jats:sub>, <jats:italic>bla</jats:italic> <jats:sub>KPC</jats:sub>, <jats:italic>bla</jats:italic> <jats:sub>NDM</jats:sub> and <jats:italic>bla</jats:italic> <jats:sub>OXA-48</jats:sub> genes.</jats:p> <jats:p> <jats:bold>Results.</jats:bold> Using the phenotypic methods, positive results were obtained for all of the analysed strains. Using PCR, carbapenemase synthesis potential was confirmed on the molecular level; the <jats:italic>bla</jats:italic> <jats:sub>VIM</jats:sub> gene was detected in 23 strains, the <jats:italic>bla</jats:italic> <jats:sub>NDM</jats:sub> gene in 26 strains and the <jats:italic>bla</jats:italic> <jats:sub>OXA-48</jats:sub> gene in two strains.</jats:p> <jats:p> <jats:bold>Conclusion.</jats:bold> There was complete agreement between the carbapenemases detected by the genetic method and the results obtained with phenotypic methods.</jats:p>

Characteristics of Carbapenem-Resistant Gram-Negative Bacilli in Patients with Ventilator-Associated Pneumonia

“…None of the isolates contained bla IMP gene [ 32 ]. Sękowska et al confirmed that bla NDM and bla VIM genes are the main antibiotic-resistance genes that induce resistance patterns to carbapenems among VAP patients in Poland [ 9 ]. Another study in Thailand reported that bla NDM was the most common carbapenen-resistant gene, present in 65% isolates [ 3 ].…”

“…Moreover, these MGEs often carry further genes that provide resistance to non-β-lactam antibiotics, further limiting treatment options for CR-GNB infections. It is therefore logical that carbapenem use would lead to the emergence of resistance [ 6 , 9 , 10 , 11 ].…”

Phenotypic and genotypic detection of carbapenemase production among gram negative bacteria isolated from hospital acquired infections

“…Among these, the most important and difficult mechanism is the production of the carbapenemase enzyme, because it is present on mobile genetic elements, which are easily transferable from one bacterium to another bacterium such as Pseudomonas spp., Acinetobacter spp., Escherichia coli )E. coli(, and Klebsiella spp., which the World Health Organization )WHO( has designated as high priority organisms in 2017. [7][8][9][10] The major carbapenemase genes are bla-Klebsiella pneumonia carbapenemase )blaKPC(, bla-oxacillin hydrolyzing enzymes-48 )blaOXA-48(, bla-New Delhi metallo-β-lactamase )blaNDM(, bla-Verona integron-mediated metallo-β-lactamase )blaVIM(, and bla-active on imipenem )blaIMP(, which are present globally and cause nosocomial infections. Many researchers have studied various methods of carbapenem resistance detection including carbapenemases.…”

Detection of Carbapenemase Genes by Molecular Method among Gram-Negative Bacilli Isolates from Tertiary Care Hospital in Dhaka, Bangladesh

“…Many researchers have studied various methods of carbapenem resistance detection including carbapenemases. 2,5,6 In this current study, we want to detect carbapenem genes which are caused imipenem resistant among Gram negative bacilli in hospital in our country.…”