Are you Agata Bilewska?

Claim your profile

Publications (5)0.98 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Serratia marcescens is an important agent in hospital infections. The aim of this paper was to compare the resistance patterns of S. marcescens strains isolated during 1 year from patients of various wards of the Institute of Transplantology. The mechanisms of beta-lactam antibiotic resistance were of especial interest. We investigated the 81 strains of S. marcescens, isolated during 2005 from patients on 3 wards and 1 clinic of the Transplantation Institute. An unusually high resistance to most antibiotics was observed among S. marcescens strains. Extended spectrum beta-lactamases (ESBLs) were probably produced by 63.2% to 84.6% of strains, depending on the ward. Additionally, about 30% of them were probably derepressed AmpC producers. The patterns of resistance indicated that at least 2 resistant clones of S. marcescens spread among the patients. One of the clones demonstrated both ESBL and derepressed AmpC production and was susceptible only to carbapenems. The second, producing ESBL, was susceptible to piperacillin/tazobactam and carbapenems. All investigated strains were resistant to nitrofurantoin. Strains of the second group were rarely susceptible to other antibiotics: aminoglycosides, ciprofloxacin, cotrimoxazole, or fosfomycin.
    Transplantation Proceedings 12/2007; 39(9):2879-82. DOI:10.1016/j.transproceed.2007.08.046 · 0.98 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: For 31 clinical strains of S. aureus the correlation between phenotype and genotype of resistance to macrolides, lincosamides and streptogramins B (MLSB) was established.. Phenotypes were determined on the basis of: susceptibility to erythromycin and clindamycin and the ability to an induction of the resistance (phenotypes S, susceptible; R , constitutive resistant, D, resistant after induction with erythromycin, D+, resistant after induction with erythromycin and with a presence of the small colonies inside inhibition zone between erythromycin and clindamycin discs), and on the basis of the resistance to spectinomycin (spR, resistant, spS, susceptible). Among examined S. aureus strains eight phenotypes of resistance to MLSB were recognized (the corresponding genotypes are given in brackets). Six phenotypes were typical: SspS (lack of MLS-B resistance genes), NEGspS (msrA/B, 1 strain), D+spS (ermCi, 4 strains),. DspR (ermAi, 11 strains and ermAi + msrA/B, 2 strains), RspR (ermAc, 4 strains and ermA + msrA/B,1 strain and ermA + ermC, 1 strain) and RspS (ermCc, 6 strains and ermB, 1 strain). Two rare phenotypes in two single strains were observed: SspR (ermAi, the strain with altered inducibility, inductor other than erythromycin) and DspS (ermAi, presumably mutation or lack of spc in Tn554).
    Medycyna doświadczalna i mikrobiologia 02/2007; 59(1):17-25.
  • [Show abstract] [Hide abstract]
    ABSTRACT: 500 strains of Serratia marcescens isolated in 2003-2005 were examined for drug susceptibility. By using several phenotypic methods it was shown that 67.6% of these strains produced ESBLs. Strains ESBL(-) and ESBL(+) were compared, paying special attention to their susceptibility to various antibiotics. It was revealed that strains ESBL(+) were much more resistant to majority of the investigated drugs. The biggest differences were in the case of amikacin and gentamicin, sensitive about 50% of ESBL(-) and 10% of ESBL(+), ciprofloxacin, sensitive 42% of ESBL(-) and 6.3% of ESBL(+) and trimethoprim/ sulphametoxazole, sensitive 45.8% of ESBL(-) and 9.4% of ESBL(+). Strains ESBL(-) retained a high susceptibility to ceftazidime (68.9%) and cefepime (71%). All strains ESBL(-) as well as ESBL(+) were susceptible to imipenem and meropenem. 78.9% of ESBL(-) and 67.3% of investigated ESBL(+) were susceptible to piperacillin/ tazobactam.
    Medycyna doświadczalna i mikrobiologia 02/2007; 59(1):35-42.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Gram-negative bacilli were examined for ESBL production by using four methods: double-disc synergy diffusion test (DDST), and three tests of combined discs with cefpodoxime, ceftazidime and cefotaxime alone and the same cephalosporins with clavulanic acid. Strains determined as ESBL-negative with all these tests were examined by using fifth method with cefpirome. 47,5% from 178 negative in other methods strains, appeared ESBL-positive in this test. The examined strains belonged to 16 different species. Most of them were Enterobacter cloaceae, Serratia marcescens, Pseudomonas aeruginosa and Acinetobacter baumanii. It seems that the combined discs method with cefpirome may be usefull for phenotypic detection of ESBL producing bacteria also in the case of strains where ESBL production is camouflaged with derepressed chromosomal AmpC beta-lactamases.
    Medycyna doświadczalna i mikrobiologia 02/2006; 58(1):59-65.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The MICs and MBCs of quinupristin/dalfopristin were determined for 22 clinical strains MRSA with inducible type of resistance to MLS-B and for 15 of their derivatives with constitutive resistance to MLS-B. For MRSA strains with inducible resistance to MLS-B the obtained results for quinupristin/ dalfopristin were: MIC50 = 0.25, MIC90 = 0.5, MBC50 = 1.0 and MBC90 = 1.0. Mutants of the same strains characterized with the following values for quinopristin/dalfopristin: MIC50 = 0.5, MIC90 = 1.5, MBC50 = 4.0 and MTC90 = 8.0.
    Medycyna doświadczalna i mikrobiologia 02/2006; 58(3):199-205.