Molecular characterization of multidrug-resistant (MDR) Pseudomonas aeruginosa isolated in a burn center.
OBJECTIVE
The aim of this study was to characterize molecularly multidrug-resistant (MDR) Pseudomonas aeruginosa isolates collected from burn center (BC) patients and environment in a hospital localized in Rio de Janeiro city, RJ, Brazil.


METHODS
Thirty-five P. aeruginosa isolates were studied. The antimicrobial resistance was tested by disk diffusion method as recommended by CLSI. The assessment of virulence (exoS and exoU) and resistance (blaPER-1, blaCTX-M, blaOXA-10, blaGES-1, blaVIM, blaIMP, blaSPM-1, blaKPC, blaNDMand blaSIM) genes were achieved through PCR and biofilm forming capacity was determined using a microtiter plates based-assay, as described previously. Genotyping was performed using Multilocus sequence typing (MLST).


RESULTS
High rate of P. aeruginosa (71.4%; 25/35) were classified as MDR, of them 64% (16/25) were related to clone A, the most prevalent clone found in the BC studied. A total of eight carbapenems resistant isolates were detected; three belonging to clone A and five carrying the exoU virulence gene. In addition, clone A isolates were also biofilm producers. Two new sequence types (ST) were detected in this study: ST2236, grouped in to clone A; and ST2237, classified in the different clones, displaying carbapenem resistance and exoU virulence gene.


CONCLUSIONS
The high prevalence of biofilm producers and multiresistant P. aeruginosa isolates in BC indicates that prevention programs need to be implemented to avoid infection in highly susceptible patients.
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Keila de Cássia Ferreira
KCF
de Almeida Silva
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Mariana Alcântara
MA
Calomino
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Gabriela
G
Deutsch
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Selma Rodrigues
SR
de Castilho
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Geraldo Renato
GR
de Paula
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Luciana Maria Ramires
LMR
Esper
Pharmacy Faculty, Universidade Federal Fluminense, Niterói, RJ, Brazil. Electronic address: tlenise@hotmail.com.
Lenise Arneiro
LA
Teixeira
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins; D018441:Biofilms; D001938:Brazil; D002053:Burn Units; D002056:Burns / Q000382:microbiology*; D015780:Carbapenems; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D016133:Polymerase Chain Reaction; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; C111749:pseudomonas exoprotein A protein, Pseudomonas aeruginosa; C405902:GES-1 beta-lactamase; C425107:beta-lactamase OXA-10; C108863:beta-lactamase PER-1; C476155:beta-lactamase SPM-1, Pseudomonas aeruginosa; D001618:beta-Lactamases
Biofilm; Carbapenem resistant; Multidrug resistant; Pseudomonas aeruginosa; Wound burn