Combination of Farnesol with Common Antifungal Drugs: Inhibitory Effect against Candida Species Isolated from Women with RVVC

Background and Objectives: Vulvovaginal candidiasis (VVC) is a mucous membrane infection, with an increased rate of antifungal resistance of Candida species. In this study, the in vitro efficacy of farnesol alone or in combination with traditional antifungals was assessed against resistant Candida strains recovered from women with VVC. Materials and Methods: Eighty Candida isolates were identified by multiplex polymerase chain reaction (PCR), and the antifungal susceptibility to amphotericin B (AMB), fluconazole (FLU), itraconazole (ITZ), voriconazole (VOR), clotrimazole (CTZ), and farnesol was tested by the standard microdilution method. The combinations of farnesol with each antifungal were calculated based on the fractional inhibitory concentration index (FICI). Result: Candida glabrata was the predominant species (48.75%) isolated from vaginal discharges, followed by C. albicans (43.75%), C. parapsilosis (3.75%), a mixed infection of C. albicans and C. glabrata (2.5%) and C. albicans and C. parapsilosis (1%). C. albicans and C. glabrata isolates had lower susceptibility to FLU (31.4% and 23.0%, respectively) and CTZ (37.1% and 33.3%, respectively). Importantly, there was "synergism" between farnesol-FLU and farnesol-ITZ against C. albicans and C. parapsilosis (FICI = 0.5 and 0.35, respectively), reverting the original azole-resistant profile. Conclusion: These findings indicate that farnesol can revert the resistance profile of azole by enhancing the activity of FLU and ITZ in resistant Candida isolates, which is a clinically promising result.

Port implantation-related bloodstream infection caused by Wickerhamomyces myanmarensis: A case report

Background and Purpose

Wickerhamomyces myanmarensis is a new opportunistic yeast previously named Pichai myanmarensis, which belongs to the order Saccharomycetales. Since its discovery, one environmental isolate of W. myanmarensis has been reported from Myanmar, and one clinical sample from Iran.

Case Report

We report a case of bloodstream infection related to an implantable venous access port. W. myanmarensis was isolated from patient's blood after chemotherapy, which was meant to control and heal T-cell lymphoblastic lymphoma. Broth dilution minimum inhibitory concentrations were performed according to the CLSI M27-A3 document. The patient recovered with intravenous voriconazole and was discharged with the recommended prescription of oral voriconazole as a maintenance drug.

Conclusion

So far, only one case of W. myanmarensis fungemia has been reported in the world in 2019. This is the second case of bloodstream infection with this yeast from a patient undergoing chemotherapy in Iran.

Species distribution and susceptibility profiles of oral candidiasis in hematological malignancy and solid tumor patients

Oral colonization and infection by Candida species are common in cancer patients receiving chemoradiotherapy, which has significantly increased in recent years. This study aimed to evaluate the frequency, distribution, and antifungal susceptibility profiles of Candida species isolates in patients with hematological malignancy and solid tumors. This study was conducted on a total of 45 cancer patients undergoing treatment with concurrent chemoradiotherapy within 2019-2020. The identification of Candida species was accomplished based on conventional examination and molecular assays. The minimum inhibitory concentrations were determined based on the guidelines of Clinical and Laboratory Standards Institute. The highest prevalence rates of oral candidiasis were observed in patients with chronic lymphoid leukemia (24.4%) and lymphoma (20%). The majority of the patients had oral candidiasis caused by non-albicans Candida species (64.4%). The results of the multiplex PCR for the identification of Candida glabrata, Candida nivariensis, Candida bracarensis, and species-specific Candida parapsilosis complex showed that all isolate amplification products at 397 bp and 171 bp were related to C. glabrata and C. parapsilosis, respectively. There was a significant difference in the Candida species distribution between the hematological malignancies and solid tumors patients. The results of MIC showed that clotrimazole, voriconazole, and caspofungin were the most effective antifungal drugs against oral non-Candida albicans isolates. An understanding of the epidemiology of oral candidiasis among hematological malignancies and solid tumors patients is currently imperative to guide optimal empirical treatment strategies for affected patients.

Black aspergilli as causes of otomycosis in the era of molecular diagnostics, a mini-review

Otomycosis refers to the fungal infection of the external auditory canal, and less commonly the middle ear. A wide range of fungi can cause this disease, however, the most common etiologies are species of Aspergillus and Candida. Until recent years, Aspergillus niger was thought to be the prevailing species of the genus Aspergillus that causes otomycosis. Using molecular methods, now, it is known that Aspergillus section Nigri comprises several morphologically similar species and all black Aspergillus isolates are not necessarily equivalent to Aspergillus niger. In this review, we focus on the species within the Aspergillus section Nigri and their role as the causative agents of otomycosis.

Use of cell surface protein typing for genotyping of azole-resistant and -susceptible Aspergillus fumigatus isolates in Iran

Aspergillus fumigatus is the leading cause of mortality in severely immunocompromised individuals. Understanding pathogen dispersion and relatedness is essential for determining the epidemiology of nosocomial infections. Therefore, the aim of this study was to investigate the diversity and putative origins of clinical and environmental azole-susceptible and -resistant A. fumigatus isolates from Iran. In all, 79 isolates, including 64 azole-susceptible and 15 -resistant isolates, were genotyped using the cell surface protein (CSP) gene. Seven distinct repeat types (r01, r02, r03, r04, r05, r06 and r07) and 11 different CSP variants (t01, t02, t03, t04A, t06A, t06B, t08, t10, t18A, t18B and t22) were observed. Interestingly, t06B, t18A and t18B were exclusively present in azole-resistant isolates. The Simpson's index of diversity (D) was calculated at 0.78. Resistant isolates were genetically less diverse than azole-susceptible isolates. However, azole-resistant A. fumigatus without TR₃₄ /L98H were more diverse than with TR₃₄ /L98H. The limited CSP type diversity of the TR₃₄ /L98H isolates versus azole-susceptible isolates suggests that repeated independent emergence of the TR₃₄ /L98H mechanism is unlikely. It has been suggested that CSP types might have a common ancestor that developed locally and subsequently migrated worldwide.

Cryptococcal meningitis due to Cryptococcus neoformans genotype AFLP1/VNI in Iran: a review of the literature

Cryptococcal meningitis is the most important opportunistic fungal infection with a high mortality in HIV-patients in less developed regions. Here, we report a case of cryptococcal meningitis in a 49-year-old HIV-positive female due to Cryptococcus neoformans (serotype A, mating-type alpha, genotype AFLP1/VNI) in Sari, Iran. In vitro antifungal susceptibility tests showed MICs of isavuconazole (0.016 μg ml(-1) ), voriconazole (0.031 μg ml(-1) ), posaconazole (0.031 μg ml(-1) ), itraconazole (0.063 μg ml(-1) ), amphotericin B (0.125 μg ml(-1) ) and fluconazole (8 μg ml(-1) ). Despite immediate antifungal therapy, the patient died 4 days later due to respiratory failure. Cryptococcal infections have been infrequently reported from Iran and therefore we analysed all published cases of cryptococcosis in Iran since the first reported case from 1969.