Investigation of ERG11 Gene Mutations in Fluconazole Resistant Candida albicans Isolated from a Number of Rasht Hospitals

Azole antifungal drugs have been a treatment option for Candida albicans infections. However, azole resistance can occur through different mechanisms such as alterations in ERG11 (lanosterol 14α-demethylase). This study assesses ERG11 gene mutations in Candida albicans strains isolated from patients with Candidia volvovaginitis in a number of Rasht hospitals between 2012-2014 by direct PCR and sequencing.
We identified the yeast strains by standard identification methods, such as germ tubes. Drug sensitivity was determined as MIC 90 values by the macrodilution broth method based on the CLSI protocol. We screened the resistant strains prior to DNA extraction and ERG11 gene mutations were confirmed by PCR sequencing.
From 40 strains, 4 showed high levels of resistance to fluconazole. Of these, two species had a MIC 90 of 512μg/ml and the other two species had a MIC 90 of 1024 μg/ml. Three strains had D116E and V456G polymorphisms.
The most fluconazole resistant Candida albicans strains worldwide were reported. Our results suggested a correlation between the polymorphism and fluconazole resistance in the Candida albicans strains.