Muriel Gazin

Publications (4) View all

• Article: Culture-based detection of methicillin-resistant Staphylococcus aureus by a network of European laboratories: an external quality assessment study.

  M Gazin, A Lee, L Derde, M Kazma, C Lammens, M Ieven, M Bonten, Y Carmeli, S Harbarth, C Brun-Buisson, H Goossens, S Malhotra-Kumar
  [show abstract] [hide abstract]
  ABSTRACT: Twenty-three hospital laboratories from Europe and Israel participated in an external quality assessment (EQA) of the culture-based detection of methicillin-resistant Staphylococcus aureus (MRSA). Participants also reported the MRSA prevalence in clinical cultures and patient screening specimens, as well as the MRSA screening practices employed at their hospitals. An EQA panel of 18 samples consisting of two MRSA harbouring SCCmec IV and I, and one strain each of methicillin-resistant coagulase-negative S. epidermidis, methicillin-sensitive S. aureus and Escherichia coli as pure strains or in mixtures at 10(7)-1 cfu absolute loads was analysed by the 23 participants. Seventeen (74%) participants identified 17 or more samples correctly. Of these, 15 (88%) utilised a chromogenic medium alone (ChromID, bioMérieux; BBL CHROMagar, BD Diagnostics; MRSA Select, Bio-Rad Laboratories) or combined with a conventional medium and up to three confirmatory tests. Proportions of MRSA among S. aureus isolated from clinical cultures varied widely, even among hospitals within countries, ranging from 11-20% to 61-70%. MRSA carriage rates were less variable (0-20%) between countries. Almost all participants (n=22, 96%) screened patients for MRSA carriage during 2009-2010, of which 15 (68%) screened intensive care unit (ICU) patients alone or combined with other targeted high-risk groups, and 10 (45%) combined nasal screening with another body site.
  European Journal of Clinical Microbiology 12/2011; 31(8):1765-70. · 2.86 Impact Factor
• Article: Evaluation of GeneOhm VanR and Xpert vanA/vanB molecular assays for the rapid detection of vancomycin-resistant enterococci.

  M Gazin, C Lammens, H Goossens, S Malhotra-Kumar
  [show abstract] [hide abstract]
  ABSTRACT: Rapid diagnosis is critical for treating and preventing infections due to vancomycin-resistant enterococci (VRE). We assessed the performance of GeneOhm VanR and Xpert vanA/vanB assays that detect vanA and vanB, the two most important genes encoding vancomycin resistance, utilizing 50 stool samples from renal dialysis patients, as well as well-characterized VRE strains. Stool samples were screened for the presence of VRE by culture followed by polymerase chain reaction (PCR) for the detection of van genes in isolates. Furthermore, the direct detection of vanA/vanB from aerobically and anaerobically pre-enriched stools was performed by in-house PCR sequencing. GeneOhm was less sensitive (43.5% vs. 73.9%) and more specific (100% vs. 92.6%) than Xpert in detecting vanA from stool samples. vanB detection by GeneOhm was more sensitive than Xpert (100% vs. 87.5%), but equally non-specific (20.6% vs. 14.7%). A further estimation on log-serial dilutions of VRE strains showed that Xpert was more sensitive at detecting VRE at low concentrations (10-100 colony forming units [cfu]/ml).
  European Journal of Clinical Microbiology 06/2011; 31(3):273-6. · 2.86 Impact Factor
• Article: Current trends in culture-based and molecular detection of extended-spectrum-β-lactamase-harboring and carbapenem-resistant Enterobacteriaceae.

  Muriel Gazin, Fabienne Paasch, Herman Goossens, Surbhi Malhotra-Kumar
  [show abstract] [hide abstract]
  ABSTRACT: The ever-expanding role of extended-spectrum-β-lactamase (ESBL)-harboring and carbapenem-resistant Enterobacteriaceae in causing serious infections poses a grave public health threat because these organisms also tend to be multidrug resistant, for which very few (if any) antibiotic options remain available. Rapid detection of such panresistant organisms offers one of the best solutions to improve patient screening and hospital infection control practices as well as curb inappropriate antibiotic use. This review discusses and compares primarily the current state-of-the-art culture-based and molecular methods that are commercially available for detection or screening of ESBL-harboring and carbapenem-resistant Enterobacteriaceae.
  Journal of clinical microbiology 01/2012; 50(4):1140-6. · 4.16 Impact Factor
• Article: Characterization of Two New CTX-M-25-Group Extended-Spectrum β-Lactamase Variants Identified in Escherichia coli Isolates from Israel.

  Jascha Vervoort, Anna Baraniak, Muriel Gazin, Julia Sabirova, Christine Lammens, Meital Kazma, Anna Grabowska, Radosław Izdebski, Yehuda Carmeli, Samir Kumar-Singh, Marek Gniadkowski, Herman Goossens, Surbhi Malhotra-Kumar
  [show abstract] [hide abstract]
  ABSTRACT: We characterized two new CTX-M-type extended-spectrum β-lactamase (ESBL) variants in Escherichia coli isolates from stool samples of two elderly patients admitted at the Tel Aviv Sourasky Medical Center, Israel. Both patients underwent treatment with cephalosporins prior to isolation of the E. coli strains. ESBLs were detected by the double-disk synergy test and PCR-sequencing of β-lactamase genes. The bla(CTX-M) genes were cloned into the pCR-BluntII-TOPO vector in E. coli TOP10. The role of amino-acid substitutions V77A and D240G was analyzed by site-directed mutagenesis of the bla(CTX-M-94) and bla(CTX-M-100) genes and comparative characterization of the resulting E. coli recombinants. MICs of β-lactams were determined by Etest. Plasmid profiling, mating experiments, replicon typing and sequencing of bla(CTX-M) flanking regions were performed to identify the genetic background of the new CTX-M variants. The novel CTX-M β-lactamases, CTX-M-94 and -100, belonged to the CTX-M-25-group. Both variants differed from CTX-M-25 by the substitution V77A, and from CTX-M-39 by D240G. CTX-M-94 differed from all CTX-M-25-group enzymes by the substitution F119L. Glycine-240 was associated with reduced susceptibility to ceftazidime and leucine-119 with increased resistance to ceftriaxone. bla(CTX-M-94) and bla(CTX-M-100) were located within ISEcp1 transposition units inserted into ∼93 kb non-conjugative IncFI and ∼130 kb conjugative IncA/C plasmids, respectively. The plasmids carried also different class 1 integrons. This is the first report on CTX-M-94 and -100 ESBLs, novel members of the CTX-M-25-group.
  PLoS ONE 01/2012; 7(9):e46329. · 4.09 Impact Factor