Molecular epidemiology and antimicrobial susceptibility of Enterococci recovered from Brazilian intensive care units.
We studied the antimicrobial resistance and the molecular epidemiology of 99 enterococcal surveillance isolates from two hospitals of Brasilia, Brazil. Conventional biochemical tests were used to identify the enterococcal species and the disk diffusion method was used to determine their resistance profiles. Enterococcus faecalis (76%) and E. faecium (9%) were the most prevalent species. No enterococci showed the vanA or vanB vancomycin resistance phenotypes or genotypes. Only the intrinsically resistant species E. gallinarum (n=2) and E. casseliflavus (n=3) harbored the vancomycin-resistance genes vanC1 and vanC2/3, respectively. We found E. faecalis isolates with high-level resistance to gentamicin (22%) and streptomycin (8%) and both E. faecalis and E. faecium isolates with resistance to more than two antimicrobials (84% and 67%, respectively). Nine E. faecalis isolates (12%) were resistant to ampicillin; the minimal inhibitory concentration (MIC) values were 16 microg/mL (n=6) and 32 microg/mL (n=3). Among these ampicillin-resistant E. faecalis, seven were also resistant to gentamicin, ciprofloxacin, rifampin, penicillin, chloramphenicol, tetracycline and erythromycin. Pulsed-field gel electrophoresis classified those isolates in three different genotypes, suggesting dissemination of genetically related ampicillin-resistant E. faecalis strains among different patients.
Titze-de-Almeida
Ricardo
R
Molecular Microbiology and Biotechnology Laboratory-MMB, University Hospital of Brasília, Brasília, DF, Brazil. titze@unb.br
Rollo Filho
Maurício
M
Nogueira
Celeste A
CA
Rodrigues
Isabela P
IP
Eudes Filho
João
J
Nascimento
Rejane S do
RS
Ferreira
Renato F
RF
Moraes
Lídia M P
LM
Boelens
Hélène
H
Van Belkum
Alex
A
Felipe
Maria Sueli Soares
MS
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001938:Brazil / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D004352:Drug Resistance, Microbial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology
D000900:Anti-Bacterial Agents