Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil

Autor(es)

Eloiza Helena Campana ^[1] ; Danilo Elias Xavier ^[2] ; Fernanda Villas-Boas Petrolini ^[3] ; Jhonatha Rodrigo Cordeiro-Moura ^[4] ; Maria Rita Elmor de Araujo ^[5] ; Ana Cristina Gales ^[6]

Afiliação do(s) autor(es)

^[1] Universidade Federal de São Paulo. Laboratório ALERTA. Disciplina de Infectologia - Brasil

^[2] Universidade Federal de São Paulo. Laboratório ALERTA. Disciplina de Infectologia - Brasil

^[3] Universidade Federal de São Paulo. Laboratório ALERTA. Disciplina de Infectologia - Brasil

^[4] Universidade Federal de São Paulo. Laboratório ALERTA. Disciplina de Infectologia - Brasil

^[5] Hospital Benemérita Sociedade Portuguesa de Beneficência - Brasil

^[6] Universidade Federal de São Paulo. Laboratório ALERTA. Disciplina de Infectologia - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Infectious Diseases; v. 21, n. 1, p. 57-62, 2017-02-00.

Resumo

Abstract The mechanisms involved in the uncommon resistance phenotype, carbapenem resistance and broad-spectrum cephalosporin susceptibility, were investigated in 25 Pseudomonas aeruginosa clinical isolates that exhibited this phenotype, which were recovered from three different hospitals located in São Paulo, Brazil. The antimicrobial susceptibility profile was determined by CLSI broth microdilution. β-lactamase-encoding genes were investigated by PCR followed by DNA sequencing. Carbapenem hydrolysis activity was investigated by spectrophotometer and MALDI-TOF assays. The mRNA transcription level of oprD was assessed by qRT-PCR and the outer membrane proteins profile was evaluated by SDS-PAGE. Genetic relationship among P. aeruginosa isolates was assessed by PFGE. Carbapenems hydrolysis was not detected by carbapenemase assay in the carbapenem-resistant and cephalosporin-susceptible P. aueruginosa clinical isolates. OprD decreased expression was observed in all P. aeruginosa isolates by qRT-PCR. The outer membrane protein profile by SDS-PAGE suggested a change in the expression of the 46 kDa porin that could correspond to OprD porin. The isolates were clustered into 17 genotypes without predominance of a specific PFGE pattern. These results emphasize the involvement of multiple chromosomal mechanisms in carbapenem-resistance among clinical isolates of P. aeruginosa, alert for adaptation of P. aeruginosa clinical isolates under antimicrobial selective pressure and make aware of the emergence of an uncommon phenotype among P. aeruginosa clinical isolates. (AU)

• Processo FAPESP: 10/12891-9 - Estudo dos transcriptomas de Pseudomonas aeruginosa, Acinetobacter baumannii e Klebsiella pneumoniae na elucidação dos seus mecanismos de resistência às polimixinas
• Beneficiário: Ana Cristina Gales
• Modalidade de apoio: Auxílio à Pesquisa - Regular