title: Risk factors for KPC-producing Klebsiella pneumoniae: watch out for surgery.
abstract: This study describes the molecular characteristics and risk factors associated with carbapenem-resistant Klebsiella pneumoniae strains. Risk factors associated with KPC-producing K. pneumoniae strains were investigated in this case-control study from May 2011 to May 2013. Bacterial identification was performed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined by broth microdilution. Carbapenemase production was assessed by both modified Hodge test (MHT) and ertapenem hydrolysis using MALDI-TOF MS. The presence of β-lactamase-encoding genes was evaluated by PCR and DNA sequencing. Alterations in genes encoding K. pneumoniae outer membrane proteins were analysed by PCR and DNA sequencing as well as SDS-PAGE. Genetic relatedness among strains was determined by pulsed-field gel electrophoresis. This study included 94 patients. Longer hospitalisation, mechanical ventilation, catheters, and previous surgery were associated with KPC-producing K. pneumoniae. Sixty-eight strains showed resistance to carbapenems. Carbapenemase production was detected by MHT in 67 K. pneumoniae strains and by MALDI-TOF MS in 57. The presence of the blaKPC-2 gene was identified in 57 strains. The blaKPC-2 gene was not found in 11 carbapenem-resistant K. pneumoniae; instead, the blaCTX-M-1-like, blaCTX-M-2-like, blaCTX-M-8 like, blaCTX-M-14-like and blaSHV- like genes associated with OmpK35 and OmpK36 alterations were observed. Thirty-three KPC-producing K. pneumoniae strains were clonally related, and patients infected with these strains had a higher mortality rate (78.78 %). Our results show that KPC-producing K. pneumoniae was associated with several healthcare-related risk factors, including recent surgery.
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Kesia Esther
authors.initials: KE
authors.lastname: da Silva
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Wirlaine Glauce
authors.initials: WG
authors.lastname: Maciel
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.|Hospital Universitário de Dourados, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Flávia Patussi Correia
authors.initials: FPC
authors.lastname: Sacchi
authors.affiliation: Laboratório ALERTA, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
authors.forename: Cecilia Godoy
authors.initials: CG
authors.lastname: Carvalhaes
authors.affiliation: Laboratório ALERTA, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Rodrigues-Costa
authors.affiliation: Laboratório ALERTA, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
authors.forename: Ana Carolina Ramos
authors.initials: ACR
authors.lastname: da Silva
authors.affiliation: Hospital Universitário de Dourados, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Mariana Garcia
authors.initials: MG
authors.lastname: Croda
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Fábio Juliano
authors.initials: FJ
authors.lastname: Negrão
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.|Laboratório ALERTA, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.|Fundação Osvaldo Cruz, Campo Grande, Mato Grasso do Sul, Brazil.
authors.forename: Julio
authors.initials: J
authors.lastname: Croda
authors.affiliation: Hospital Universitário de Dourados, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Gales
authors.affiliation: Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande Dourados - UFGD, Dourados, Mato Grasso do Sul, Brazil.
authors.forename: Simone
authors.initials: S
authors.lastname: Simionatto
mesh_terms: D016022:Case-Control Studies; D024881:Drug Resistance, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000382:microbiology*; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases; C547585:beta-lactamase KPC-2, Klebsiella pneumoniae