Fluconazole was used to test the susceptibility of Candida albicans isolated from different clinical samples, and to detect mutations in ERG11 gene, and their relationship to fluconazole resistance. Forty-eight isolates of Candida albicans were tested for susceptibility using the disc diffusion method (M-44). ERG11 genes of six isolates were amplified (four resistant, two susceptible) and sequenced. The sequenced genes were analyzed to detect the mutations. Out of 48 isolates of Candida albicans, 4 (8%) were resistant to fluconazole. Sixteen-point mutations were detected included 13 silent mutations, and three missense mutations. The mutations of A945C (E266D) and G1609A (V488I) were found only in susceptible Candida albicans isolates, while the mutation of G1456A (V437I) was detected only in resistant Candida albicans isolates. Candida albicans had a high susceptibility against fluconazole. The amino acid substitutions of E266D and V488I have no role in fluconazole resistance, while the substitution of V437I may have a role in developing resistance against fluconazole. Multiple point mutations in ERG11 gene may develop resistance to fluconazole.
