Polymyxin Resistance in Clinical Isolates of K. pneumoniae in Brazil: Update on Molecular Mechanisms, Clonal Dissemination and Relationship With KPCProducing Strains

dc.creatorConceição Neto, Orlando C.
dc.creatorCosta, Bianca Santos da
dc.creatorPontes, Leilane da Silva
dc.creatorSilveira, Melise Chaves
dc.creatorSilva, Lívia Helena Justo da
dc.creatorSantos, Ivson Cassiano de Oliveira
dc.creatorTeixeira, Camila Bastos Tavares
dc.creatorOliveira, Thamirys Rachel Tavares e
dc.creatorHermes, Fernanda Stephens
dc.creatorGalvão, Teca Calcagno
dc.creatorAntunes, L. Caetano M.
dc.creatorSouza, Cláudio Marcos Rocha de
dc.creatorCarvalho-Assef, Ana P. D.
dc.date2022-08-11T11:36:56Z
dc.date2022-08-11T11:36:56Z
dc.date2022
dc.date.accessioned2023-09-26T21:34:13Z
dc.date.available2023-09-26T21:34:13Z
dc.identifierCONCEIÇÃO NETO, Orlando C. et al. Polymyxin Resistance in Clinical Isolates of K. pneumoniae in Brazil: Update on Molecular Mechanisms, Clonal Dissemination and Relationship With KPCProducing Strains. Frontiers in Cellular and Infection Microbiology, v. 12, Article 898125, p. 1 - 13, July 2022.
dc.identifier2235-2988
dc.identifierhttps://www.arca.fiocruz.br/handle/icict/54584
dc.identifier10.3389/fcimb.2022.898125
dc.identifier.urihttps://repositorioslatinoamericanos.uchile.cl/handle/2250/8872851
dc.descriptionIn Brazil, the production of KPC-type carbapenemases in Enterobacteriales is endemic, leading to widespread use of polymyxins. In the present study, 502 Klebsiella pneumoniae isolates were evaluated for resistance to polymyxins, their genetic determinants and clonality, in addition to the presence of carbapenem resistance genes and evaluation of antimicrobial resistance. Resistance to colistin (polymyxin E) was evaluated through initial selection on EMB agar containing 4% colistin sulfate, followed by Minimal Inhibitory Concentration (MIC) determination by broth microdilution. The susceptibility to 17 antimicrobials was assessed by disk diffusion. The presence of blaKPC, blaNDM and blaOXA-48-like carbapenemases was investigated by phenotypic methods and conventional PCR. Molecular typing was performed by PFGE and MLST. Allelic variants of the mcr gene were screened by PCR and chromosomal mutations in the pmrA, pmrB, phoP, phoQ and mgrB genes were investigated by sequencing. Our work showed a colistin resistance frequency of 29.5% (n = 148/502) in K. pneumoniae isolates. Colistin MICs from 4 to >128 μg/mL were identified (MIC50 = 64 μg/mL; MIC90 >128 μg/mL). All isolates were considered MDR, with the lowest resistance rates observed for amikacin (34.4%), and 19.6% of the isolates were resistant to all tested antimicrobials. The blaKPC gene was identified in 77% of the isolates, in consonance with the high rate of resistance to polymyxins related to its use as a therapeutic alternative. Through XbaI-PFGE, 51 pulsotypes were identified. MLST showed 21 STs, with ST437, ST258 and ST11 (CC11) being the most prevalent, and two new STs were determined: ST4868 and ST4869. The mcr-1 gene was identified in 3 K. pneumoniae isolates. Missense mutations in chromosomal genes were identified, as well as insertion sequences in mgrB. Furthermore, the identification of chromosomal mutations in K. pneumoniae isolates belonging from CC11 ensures its success as a high-risk epidemic clone in Brazil and worldwide.
dc.formatapplication/pdf
dc.languageeng
dc.publisherFrontiers Media
dc.rightsopen access
dc.subjectResistência à polimixina
dc.subjectKlebsiella pneumoniae
dc.subjectResistência a antibióticos
dc.subjectgene Mcr
dc.subjectPhoPQ and PmrAB
dc.subjectPolymyxin resistance
dc.subjectKlebsiella pneumoniae
dc.subjectAntibiotic resistance
dc.subjectMcr gene
dc.subjectPhoPQ and PmrAB
dc.titlePolymyxin Resistance in Clinical Isolates of K. pneumoniae in Brazil: Update on Molecular Mechanisms, Clonal Dissemination and Relationship With KPCProducing Strains
dc.typeArticle


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