Multidrug-resistant Klebsiella pneumoniae harboring extended spectrum β-lactamase encoding genes isolated from human septicemias

• DOI: 10.1371/journal.pone.0250525
• Publication Date: 2021-05-04T19:39:45Z
• Authors: Isabel Carvalho; Nadia Safia Chenouf; José António Carv...; Ana Paula Castro; Vanessa Silva; Rosa Capita; Carlos Alonso-Cal...; Maria de Lurdes N...; Gilberto Igrejas; Carmen Torres; Patrícia Poeta
• Keywords: Multilocus sequence typing

Klebsiella pneumoniae is a major pathogen implicated in nosocomial infections. Extended-spectrum β-lactamase (ESBL)-producing K . isolates are public health concern. We aim to characterize the type of β-lactamases and associated resistance mechanisms ESBL-producing obtained from blood cultures Portuguese hospital, as well determine circulating clones. Twenty-two cefotaxime/ceftazidime-resistant (CTX/CAZ R ) were included study. Identification was performed by MALDI-TOF MS antimicrobial susceptibility testing disk-diffusion. The screening test for ESBL-production ESBL-producer further characterized. presence different beta-lactamase genes ( bla CTX-M , SHV TEM KPC NDM, VIM, OXA-48, CMY-2 DHA-1, FOX, MOX, ACC analyzed PCR/sequencing isolates, other aac(6’)-Ib-cr tet A/B, dfrA qnr A/B/S, sul 1/2/3) or integron-related int 1/2/3). Multilocus-sequence-typing (MLST) selected isolates. ESBL activity detected 12 22 CTX/CAZ 11 them carried CTX-M-15 gene (together with remaining isolate SHV-106 gene. All harboring also contained SHV-1 SHV-11 SHV-27 variants). Both correspond ESBL-variants. Two producing carbapenemase KPC2/3 OXA-48 showed imipenem resistance. majority 1 gene, sulphonamide-resistance 2 and/or 3); tetA all eight tetracycline-resistant Three genetic lineages found isolates: ST348 (one CTX-M-15/TEM/SHV-27/KPC-2/3-producer isolate), ST11 (two CTX-M-15/TEM/SHV-1- CTX-M-15-TEM-SHV-11-OXA-48-producer isolates) ST15 SHV-106/TEM-producer isolate). enzymes SHV-type among some cases association carbapenemases type.