Abstract
We have noted that, during the last few years, there has been a redistribution of the most common Candida species with an increase in non-C. albicans Candida species, particularly Candida glabrata. In many countries, the high frequency of Candida glabrata shows the highest resistance rates. The main objective of this investigation was to analyze the genotypic variability of invasive C. glabrata isolates recovered over a period of six years and assess their in vitro susceptibility to fluconazole to determine the possible existence of relationships between genotype and susceptibility. We collected 50 invasive C. glabrata isolates (21.4%) from January 2001 to December 2007. The in vitro susceptibility profiles as determined by the E-test method showed that 8.3% of the isolates were resistant to fluconazole. The typing with three microsatellite markers RPM2, MTI and ERG3 demonstrated 12 multilocus genotypes distributed irregularly with a predominance of G1 (38%). A cluster (G9) was found among isolates collected in the same ward, at the same time period, suggesting cross transmission. Eleven of 13 patients who had previously been colonized by C. glabrata, were infected by their colonizing strains. However, we noted after prolonged treatment with fluconazole that there was an increase of the MIC for an isolate from one patient and in another patient, the selection of a more resistant variant. In our study, we didn't find an association between genotype and susceptibility to fluconazole. In conclusion, the predominance of some genotypes could be explained by nosocomial transmission or a selective ecological advantage rather than an emergence of a resistant isolate.
Acknowledgement
This study was financially supported by the Ministry of Higher Education and Scientific Research.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
This paper was first published online on Early Online on 1 July 2010.