Carbapenemase production among less-common Enterobacterales genera: 10 US sites, 2018

Abstract

Background Historically, United States’ carbapenem-resistant Enterobacterales (CRE) surveillance and mechanism testing focused on three genera: Escherichia, Klebsiella, and Enterobacter (EsKE); however, other genera can harbour mobile carbapenemases associated with CRE spread. Objectives From January through May 2018, we conducted a 10 state evaluation to assess the contribution of less common genera (LCG) to carbapenemase-producing (CP) CRE. Methods State public health laboratories (SPHLs) requested participating clinical laboratories submit all Enterobacterales from all specimen sources during the surveillance period that were resistant to any carbapenem (Morganellaceae required resistance to doripenem, ertapenem, or meropenem) or were CP based on phenotypic or genotypic testing at the clinical laboratory. SPHLs performed species identification, phenotypic carbapenemase production testing, and molecular testing for carbapenemases to identify CP-CRE. Isolates were categorized as CP if they demonstrated phenotypic carbapenemase production and ≥1 carbapenemase gene (blaKPC, blaNDM, blaVIM, blaIMP, or blaOXA-48-like) was detected. Results SPHLs tested 868 CRE isolates, 127 (14.6%) were from eight LCG. Overall, 195 (26.3%) EsKE isolates were CP-CRE, compared with 24 (18.9%) LCG isolates. LCG accounted for 24 (11.0%) of 219 CP-CRE identified. Citrobacter spp. was the most common CP-LCG; the proportion of Citrobacter that were CP (11/42, 26.2%) was similar to the proportion of EsKE that were CP (195/741, 26.3%). Five of 24 (20.8%) CP-LCG had a carbapenemase gene other than blaKPC. Conclusions Participating sites would have missed approximately 1 in 10 CP-CRE if isolate submission had been limited to EsKE genera. Expanding mechanism testing to additional genera could improve detection and prevention efforts.

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

“…Enterobacterales is an order of Gram-negative bacteria, comprising seven families and more than 80 genera. It incorporates pathogens accountable for 30% of HAIs [ 6 ]. The global priority list of pathogens by the World Health Organization (WHO) has categorized CRE, CRPA, and CRA as critical or highest priority [ 7 ].…”

“…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.…”

“…Many researchers have studied various methods of carbapenem resistance detection including carbapenemases. 8 , 11 , 12 Methodologies for the detection of carbapnem resistance range from conventional disc diffusion and minimum inhibitory concentration (MIC) determination methodologies to advanced and rapid detection methods such as automated methods, RAPIDEC ® CARBA NP (Biomeriux Private Limited, South Delhi, India), and genotypic methods using polymerase chain reaction (PCR). Many of these advanced methodologies are not routinely used in peripheral and resource poor settings because of which detection of these resistant organisms is missed or delayed which in turn, leads to therapeutic failure and dissemination of these resistant strains in the hospitals.…”

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

“…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 organismsin 2017. 3,4 The major carbapenemase genes are bla-Klebsiella pneumoniacarbapenemase (blaKPC), bla-oxacillin hydrolyzing enzymes-48 (blaOXA-48), bla-New Delhi metallo-â-lactamase (blaNDM), bla-Verona integron-mediated metallo-â-lactamase (blaVIM), and blaactive on imipenem (blaIMP), which are present globally and cause nosocomial infections. Many researchers have studied various methods of carbapenem resistance detection including carbapenemases.…”