Activities of fluconazole in combination with terbinafine against non-albicans Candida species isolated from the patients with recurrent vulvovaginal candidiasis in comparison with ciclopirox olamine

Introduction: Recent epidemiological studies show that episodes due to non-albicans species of Candida (C) such as Candida tropicalis, C. glabrata, C, krusei, C. parapsilosis appear to be increasing in recurrent vulvovaginal candidiasis (RVVC). Increased use of the current antifungal drugs cause drug resistance among Candida species. In order to gain suitable antifungal therapy for this disease, we investigated the activity of synergism of fluconazole and terbinafine comparing with cyclopirox olamine, against non-albicans Candida species isolated from recurrent candidal vaginitis. Methods: This study was carried out on 44 strains of non-albicans Candida species that were isolated from patients with recurrent vulvovaginal candidiasis. Antifungal susceptibility testing of fluconazole and terbinafine alone and combination of these drugs on non- albicans species were determined by Clinical and Laboratory Standard Institute (CLSI) microdilution method (document M27-A2). Results: The mean of MICs of fluconazole, terbinafine and cyclopirox olamine was 93.8, 104.7 and 18 µg/ml, respectively, after 48 hours of incubation. FICs of fluconazole in combination with terbinafine were shown ineffective and additive in 42 isolates (95.5%), synergism and relative-synergism were obtained in two isolates (4.5%). Additionally, the mean of cyclopirox olamine MFCs (32 g/ml) had the most effective and the mean of terbinafine MFCs (177 g/ml) showed the lowest effectiveness on non-albicans isolates (P>0.05). Conclusion: Most of isolates were resistant against fluconazole and terbinafine, and combination of these drugs did not affect clinical isolates. But cyclopirox olamine with the lowest mean of MICs and MFCs showed the highest activity in non-albicans isolates.