Objective. Candida krusei causes approximately 1% of vulvovaginal candidiasis (VVC) cases and is naturally resistant to fluconazole. Antifungal testing may be required if C. krusei vaginitis fails to respond to non-fluconazole therapy, particularly in patients with recurrent infections. Design. We investigated the clinical characteristics and antifungal susceptibility profile of vaginal C. krusei isolates. Between 2009 and 2012, we identified 560 unrelated Candida spp.-positive vaginal cultures, of which 28 (5.0%) were C. krusei. These isolates were analyzed according to host factors and the clinical forms of VVC, and their in vitro susceptibility to 10 antifungal agents was tested using a reference microdilution method. Results. We observed that perineal laceration and increased age (>50 years) were significant predictors of C. krusei in vaginal samples ( ). All isolates were susceptible to amphotericin B, caspofungin, ketoconazole, and miconazole. Additionally, susceptible dose-dependent and resistant rates were found for fluconazole as 42.9% and 57.1%, respectively. Remarkably, only 42.9% and 67.9% of the isolates were susceptible to itraconazole and voriconazole, respectively. Conclusions. Understanding local susceptibility patterns, especially those of non-C. albicans Candida species, can significantly aid in the selection of an effective antifungal agent. The in vivo response of C. krusei vaginitis to various antifungal therapeutics remains unknown and requires further research. 1. Introduction Vulvovaginal candidiasis (VVC) is a common illness attributed to an overgrowth of Candida species, and it is estimated that 75% of all women will experience an episode of VVC in their lifetimes. C. albicans accounts for 80–95% of all episodes of VVC worldwide [1, 2]. The prevalence of VVC due to non-C. albicans Candida species previously ranged from 5 to 20%; however, the number of reported cases has increased sharply over the last two decades, particularly for cases of C. glabrata [3, 4]. Therefore, the possibility of antifungal resistant strains of non-C. albicans Candida species in Candida vaginitis should be considered in clinics. The emergence of resistance may be attributed to the following factors (i) the widespread use of over-the-counter (OTC) medications; (ii) long-term use of suppressive azoles; and (iii) the frequent use of courses of antifungal medications [1, 3] or (iv) the increase use of vaginal cultures for reliable diagnoses [2, 5]. There is no evidence to suggest the followings: (i) certain women may be more susceptible to infection by
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