Decreased susceptibility to glycopeptides in methicillin-resistant Staphylococcus aureus: a 20 year study in a large French teaching hospital, 1983-2002.
OBJECTIVE
To assess the evolution of glycopeptide susceptibility in methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in a large French teaching hospital from 1983 to 2002.


METHODS
Determination of glycopeptide MICs by using the Etest method in Mueller-Hinton agar on a sample of randomly selected MRSA strains.


RESULTS
A total of 1445 MRSA strains were tested, and one vancomycin-intermediate MRSA (VISA) and 31 teicoplanin-intermediate MRSA (TISA) strains were detected. The first strains were detected in 1985, and all strains were gentamicin resistant (GR). None of the gentamicin-susceptible strains had a glycopeptide MIC > 3 mg/L. In addition, there was a significant increase in glycopeptide MIC geometric means over the years, and this increase was higher for teicoplanin than for vancomycin.


CONCLUSIONS
The higher increase in teicoplanin MICs, and the good correlation between vancomycin and teicoplanin MICs, suggests systematic determination of teicoplanin MIC to screen for abnormal glycopeptide susceptibility among GR-MRSA.
Robert
Jérôme
J
Université Pierre et Marie Curie-Paris6, AP-HP, Hôpital Pitié-Salpêtrière, Laboratoire de Bactériologie-Hygiène, Paris, F75013, France. jrobert@chups.jussieu.fr
Bismuth
Roland
R
Jarlier
Vincent
V
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D005602:France / Q000453:epidemiology; D006020:Glycopeptides / Q000494:pharmacology*; D006761:Hospitals; D006801:Humans; D016106:Methicillin Resistance; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D013997:Time Factors
D000900:Anti-Bacterial Agents; D006020:Glycopeptides