Introduction: Candida dubliniensis and C. albicans are very similar in morphology and phenotypic characteristics.Approximation of this yeast species has caused major problems in identifying these two correctly.Materials and Methods: To distinguish among sixty yeast clinical isolates from patients with cancer, polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) was done.Results: PCR-RFLP of the ITS region showed different patterns between Candida dubliniensis and C. albicans after digestion with enzymes BlnI. All of the Clinical isolates were diagnosed as C.albicans. The results were confirmed by sequencing and RAPD-PCR.Conclusion: PCR-RFLP would be a useful and applicable technique in clinical laboratories for discrimination of C. albicans and C. dubliniensis.

Background and Purpose: Resistance to antifungal drugs is increasing among Candida isolates from patients with vulvovaginal candidiasis (VVC). Lack of correct diagnosis of Candida causing VVC and the experimental use of antifungal drugs are the main causes of this resistance. This study aimed to determine the susceptibility of antifungal drugs against Candida species isolated from VVC in Northeastern Iran. Materials and Methods: Among women suspected of VVC, 189 vaginal discharge specimens were evaluated. Candida isolates detected by polymerase chain reaction-restriction fragment length polymorphism were examined by standard antifungal disk diffusion susceptibility testing method for voriconazole, itraconazole, fluconazole, and ketoconazole. The susceptibility pattern of these antifungals was reported as sensitive, susceptible dose-dependent, and resistant. The results were evaluated by SPSS software and analyzed by Pearson chi-squared test. Results: Among the vaginal specimens, 108 out of 189 Candida isolates were identified as C. albicans, C. glabrata, C. kefyr, C. parapsilosis, and C. tropicalis. The susceptibility rates of Candida isolates to voriconazole, ketoconazole, itraconazole, and fluconazole were 92. 6%, 90. 7%, 68. 5%, and 63. 9%, respectively. Moreover, the resistance rates to fluconazole, itraconazole, ketoconazole, and itraconazole were 15. 7%, 8. 3%, 1. 9%, and 1. 9%, respectively. The C. glabrata and C. albicans isolates were resistant to antifungal discs among 93% and 20% of the specimens, respectively. Conclusion: The C. glabrata and C. albicans species showed the highest resistance to antifungal drugs. Furthermore, Candida isolates showed the highest sensitivity to voriconazole and ketoconazole and the lowest sensitivity to fluconazole.

Background and Purpose: Oropharyngeal candidiasis is the most prevalent opportunistic fungal infection in patients with human immunodeficiency virus (HIV) as well as other immunodeficiency disorders, which is caused by various Candida species, mostly Candida albicans. Studies have shown that Candida isolates differ in their pathogenicity. These variations are attributed to virulence factors, host characteristics, and the target tissue. This study aimed to determine and compare the secretion of hydrolytic enzymes in C. albicans and non-albicans Candida species isolated from HIV+/AIDS patients and healthy individuals. Materials and Methods: Samples were taken from 201 patients with HIV and 118 healthy individuals. The samples were identified by macroscopic, phenotypic, and molecular methods, and virulence factors were subsequently measured. Statistical differences in enzymatic activity of various Candida isolates were calculated (P<0. 0001). Results: In total, 95 samples (47. 20%) from patients and 46 samples (38. 90%) from healthy individuals were positive for the growth of different Candida species. There were 39 (41. 10%) and 36 (78. 30%) C. albicans in patients and healthy individuals, respectively, as well as 56 (58. 90%) and 10 (21. 70%) non-albicans species in patients and healthy subjects, respectively. All the enzymes produced by Candida species enzymes were at low, medium, and high levels. Hemolysin activity in Candida species isolated from patients was significantly higher, compared to healthy individuals. Moreover, the activity of all C. albicans enzymes in patients was significantly higher than other Candida species. Conclusion: The C. albicans isolated from HIV-positive individuals secreted higher amounts of exoenzymes, and can cause oropharyngeal candidiasis and become a source of candidiasis for the host.

Background: Yeasts are increasingly implicated in serious systemic infections. The aim of this study was to identify Candida albicans and C. dubliniensis from isolates of immunocompromised patients and evaluate the in vitro antifungal activities of them against antifungal agents.Methods: One hundred and seventy eight C. albicans were isolated by routine methods from 403 immunocompromised patients. All isolated C. albicans were inoculated on CHROMagar Candida medium. The carbohydrate assimilation patterns of all the isolates were studied, using the API 32C system. To identify C. albicans and C. dubliniensis, PCR was done by specific primers. The susceptibility test for the isolates was performed by a broth microdilution assay, according to the Clinical and Laboratory Standard Institute.Results: Of 178 isolates C. albicans, six were C. dubliniensis with PCR assay, and 7% were resistant to amphotericin B, 4.6% to fluconazole, 7% to itraconazole, 1% to nystatin, 2.3% to voriconazole, and 7% to ketoconazole. None of the C. dubliniensis isolates were resistant to the six anti-fungal agents.Conclusion: It would be convenient to carry out antifungal susceptibility studies in order to establish the in-vitro activities of antifungal agents against local isolates and also to detect shifts toward resistance as early as possible.