burns 37 (2011) 1202–1207
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Multiple-locus variable number of tandem repeats (VNTR)
fingerprinting (MLVF) and antibacterial resistance profiles of
extended spectrum beta lactamase (ESBL) producing
Pseudomonas aeruginosa among burnt patients in Tehran
Fereshteh Jabalameli a, Akbar Mirsalehian a, Nazli Sotoudeh a, Leila Jabalameli a,
Marzieh Aligholi a, Babak Khoramian a, Morovat Taherikalani b, Mohammad Emaneini a,*
a
b
Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
article info
abstract
Article history:
Extended spectrum b-lactamase (ESBL)-producing trait was present in 48 out of the 112
Accepted 25 May 2011
(42.8%) Pseudomonas aeruginosa isolates collected from burn wound infections during a 12month period. The presence of oxa-10, per-1, veb-1 and ges genes and the multiple-locus
Keywords:
variable number of tandem repeats (VNTR) fingerprinting (MLVF) of 112 P. aeruginosa strains
Pseudomonas aeruginosa
were determined by PCR and multiplex PCR. Disk diffusion methods were used to determine
VNTR
the susceptibility of the isolates to antimicrobial agents as instructed by CLSI. All ESBL
ESBL
isolates were resistant to aztreonam, cefepime, cefotaxime, cefpodoxime, ceftazidime,
Burn
ceftriaxone and ofloxacin. Fewer than 60% of ESBL isolates were resistant to imipenem,
meropenem, and piperacillin-tazobactam but more than 90% were resistant to amikacin,
ciprofloxacin, levofloxacin, ticarcillin and tobramycin. The most prevalent ESBL genes
included oxa-10 (70%) and per-1 (50%) followed by veb-1 (31.3%). The gene encodes GES
enzyme did not detect in any isolates. A total of 100 P. aeruginosa strains were typed by MLVF
typing method. MLVF produced 42 different DNA banding patterns. These data indicate that
different MLVF types infect burn wounds in patients at a hospital in Tehran and also suggest
an alarming rate of ESBL-producing isolates in this test location.
# 2011 Elsevier Ltd and ISBI. All rights reserved.
1.
Background
Pseudomonas aeruginosa is a gram-negative bacterium found in
soil, water, skin flora, and most man-made environments
throughout the world. It is an opportunistic pathogen which
can cause nosocomial infections. Burnt patients are at a high
risk for colonization and serious wound infections of P.
aeruginosa isolates [1,2]. Treatment of these infections is
frequently complicated by antibiotic resistance [3]. The
majority of P. aeruginosa isolates naturally exhibit varying
degrees of resistant to many antibiotics. Acquired resistance is
also reported by the production of mobile genetic elements or
plasmid-mediated b-lactamase [4]. The emergence and dissemination of extended spectrum b-lactamase (ESBL) producing P. aeruginosa is of great global concern. The most common
type of ESBL in P. aeruginosa belongs to Ambler class A. This
class includes enzymes TEM, SHV, PER, VEB, GES and IBC that
confer resistance to several expanded-spectrum cephalosporins [5]. The GES families of enzyme have broad hydrolysis
* Corresponding author at: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, 100 Poursina St.,
Keshavarz Blvd., Tehran, Iran. Tel.: +98 021 8895 5810; fax: +98 021 8895 5810.
E-mail addresses: [email protected], [email protected] (M. Emaneini).
0305-4179/$36.00 # 2011 Elsevier Ltd and ISBI. All rights reserved.
doi:10.1016/j.burns.2011.05.012