Resistance to carbapenems among Pseudomonas aeruginosa isolated from patients of transplant wards.
BACKGROUND
The aim of the study was to estimate the carbapenems resistance and occurrence of metallo-beta-lactamase (MBL) production among Pseudomonas aeruginosa isolated from patients during the last 2 years.


METHODS
We investigated all P aeruginosa strains derived from Transplantation Institute patients, hospitalized from January 2007 to December 2008. E-tests as well as the three-discs method with imipenem, ceftazidime were used for MBL detection. For the chosen strains, a PCR method was applied for detection of genes determining VIM, IMP, and SMP.


RESULTS
Among 311 isolated strains from 228 patients only one strain was used for each patient. We showed increased resistance to carbapenems among P aeruginosa in 2008 compared with 2007: from 14% to 22%. About 60% of resistant strains displayed the MBL phenotype. Upon PCR analysis, the VIM-type metallo-beta-lactamase was detected in 70% of them.


CONCLUSIONS
Despite similar numbers of P aeruginosa-infected patients in 2007 and 2008, the percentage of MBL-producing strains increased from 7% to 15%. Most MBLs belonged to the VIM type.
Mlynarczyk
G
G
Department of Medical Microbiology, Transplantology and Internal Diseases of Transplantation Institute, The Medical University of Warsaw, Chalubinskiego 5 02-004 Warsaw, Poland. grazyna.mlynarczyk@wum.edu.pl
Sawicka-Grzelak
A
A
Szymanek
K
K
Buczkowska
T
T
Pazik
J
J
Durlik
M
M
Pacholczyk
M
M
Lagiewska
B
B
Chmura
A
A
Paczek
L
L
Mlynarczyk
A
A
D015780:Carbapenems / Q000494:pharmacology* / Q000627:therapeutic use; D017931:DNA Primers; D024881:Drug Resistance, Bacterial; D006801:Humans; D016133:Polymerase Chain Reaction; D011552:Pseudomonas Infections / Q000188:drug therapy*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D014180:Transplantation / Q000009:adverse effects*; D001618:beta-Lactamases / Q000235:genetics*
D015780:Carbapenems; D017931:DNA Primers; D001618:beta-Lactamases