Molecular characterization of carbapenem-resistant Klebsiella pneumoniae isolates from a university hospital in Brazil

Abstract

Introduction: The emergence of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kpn) isolates is attracting significant attention in nosocomial infection settings. K. pneumoniae is the main pathogen that harbours blaKPC genes. Methodology: This study evaluated 54 K. pneumoniae carbapenem-resistant isolates from patients hospitalized at the University Hospital of Londrina, between July 2009 and July 2010. The isolates were phenotypically screened for carbapenemase production and submitted for genotypic confirmation by polymerase chain reaction (PCR) for KPC, metallo-β-lactamases, OXA-48, and extended-spectrum beta-lactamase genes. The absence of outer membrane proteins (OMP) was investigated by SDS-PAGE. The susceptibility profile was determined by broth microdilution, according to Clinical and Laboratory Standards Institute protocol. Results: All isolates were phenotypically positive for class A carbapenemase production, but negative for metallo-β-lactamase activity. PCR analysis demonstrated that all isolates carried blaKPC genes and sequencing showed that all strains belonged to KPC-2 subtype. Four strains did not show porin expression, and all isolates were resistant to ertapenem, meropenem, and imipenem. Susceptibility rates reached 35.2% for gentamicin, 85.2% for polymixyn B, 87% for colistin, and 98.1% for both tigecycline and fosfomycin. Pulsed-field gel electrophoresis showed six clones, and three of them predominated among the isolates. Conclusions: KPC-2-producing K. pneumoniae is becoming predominant among carbapenem-resistant K. pneumoniae isolates at the hospital. The association of the enzyme KPC with other resistance determinants, such as loss of porins, may increase the severity of the situation of nosocomial infections. There is an urgent need to develop strategies for infection control and prevention.

Analysis of diverse β-lactamases presenting high-level resistance in association with OmpK35 and OmpK36 porins in ESBL-producing Klebsiella pneumoniae

“…The MIC 50 and MIC 90 showed several bacterial strains that were highly resistant to the different groups of drugs. The lowest resistance rates were observed against colistin and tigecycline, agreeing with a prior study from Brazil ( Vivan et al, 2017 ). However, emerging colistin resistance has been reported from China ( Liu et al, 2021 ).…”

Phenotypic Detection of Carbapenem Resistance in Clinical Isolate of Klebsiella Pneumoniae in Tertiary Care Hospital

“…It is implicated in various infections like pneumonia, blood stream infection, urinary tract infection and hepatic abscess. 33 In the current study majority of K. pneumoniae were isolated from urine cultures (29.7%) ( 36 who reported maximum isolation of K. Pneumoniae from urine samples. K. pneumoniae is the second most common cause of UTI after E. coli.…”

Molecular Detection of Carbapenem Resistance in Clinical Isolates of Klebsiella pneumoniae in Tertiary Care Hospital

“…In their study, among the carbapenemases coexpression of bla NDM and bla OXA48 -like was observed in 28%, bla NDM in 19%, bla OXA48 -like in 13% and bla KPC was not found. In the study of Vivan et al, 32 the isolates that were phenotypically screened for carbapenemase production were subjected for genotypic confirmation by PCR (PCR) for KPC, metallo-b-lactamases, OXA-48, and extendedspectrum beta-lactamase genes. PCR analysis demonstrated that all isolates carried bla KPC genes and sequencing showed that all strains belonged to KPC-2 subtype.…”