Neoscytalidium dimidiatum as onychomycosis causative agent in an Iranian patient: a case report and literature review.

A 38-year-old healthy male presented to our medical mycology center with whitish opaque discoloration of the right toenail. He reported a history of some sand scratches subsequent to walking barefoot on the beach two years ago and wearing hard safety shoes for a period of two years. On clinical examination, onycholysis, onychodystrophy, and apparent thickening of the ungual bed in the left big toe were found. The microscopic examination of nail clippings using 15% potassium hydroxide (KOH/) revealed the presence of septate pigmented hyphae. The fungus was identified as Neoscytalidium dimidiatum based on the cultural characteristics, the arrangement of arthroconidia on lactophenol cotton blue (LPCB) staining, blocky-brown pigmented hyphae on serum physiology mounts, and sequencing. Susceptibility of the isolated fungi to amphotericin B, itraconazole, voriconazole, and terbinafine was tested using the standard broth microdilution M38-A2 method developed by the Clinical and Laboratory Standards Institute (CLSI). The minimum inhibitory concentrations (MICs) of the four antifungal drugs used in this study were: amphotericin B: 1 mg/L, itraconazole: 2 mg/L, voriconazole: 0.25 mg/L, and terbinafine: 1 mg/L. The patient underwent terbinafine and clobetasol topical treatments for 6 months.

Comparison of in vitro antifungal activity of novel triazoles with available antifungal agents against dermatophyte species caused tinea pedis.

OBJECTIVE: Dermatophytes are a group of keratinophilic fungi that invade and infect the keratinized tissues and cause dermatophytosis. We investigated effectiveness of novel triazole (luliconazole and lanaconazole) in comparison with available antifungal agents against dermatophyte species isolated from patients with tinea pedis. MATERIAL AND METHODS: A total of 60 dermatophytes species were isolated from the patients with tinea pedis. Identification of species was done by DNA sequencing of the ITS1-5.8S rDNA-ITS2 rDNA region. In vitro antifungal susceptibility testing with luliconazole and lanaconazole and available antifungal agent was done in accordance with the Clinical and Laboratory Standards Institute, M38-A2 document. RESULTS: In all investigated isolates, luliconazole had the lowest minimum inhibitory concentration (MIC) (MIC range=0.0005-0.004µg/mL), while fluconazole (MIC range=0.4-64µg/mL) had the highest MICs. Geometric mean MIC was the lowest for luliconazole (0.0008µg/mL), followed by lanoconazole (0.003µg/mL), terbinafine (0.019µg/mL), itraconazole (0.085 µg/mL), ketoconazole (0.089µg/mL), econazole (0.097µg/mL), griseofulvin (0.351 µg/mL), voriconazole (0.583µg/mL) and fluconazole (11.58µg/mL). CONCLUSION: The novel triazoles showed potent activity against dermatophytes and promising candidates for the treatment of tinea pedis caused by Trichophyton and Epidermophyton species. However, further studies are warranted to determine the clinical implications of these investigations.

A systematic review and meta-analysis on the epidemiology, casual agents and demographic characteristics of onychomycosis in Iran.

Onychomycosis or fungal nail infection is one of the most common fungal infections. Nearly 50% of all nail disorders are caused by fungi. This systematic review and meta-analysis was conducted to determine the prevalence of onychomycosis across Iran. We searched English and Persian databases for studies reporting the epidemiologic features of onychomycosis in Iranian people from January 2000 to December 2018. Literature search revealed 307 studies, of which 24 studies met the eligibility criteria. In order to identifying the existence of publication bias among studies, funnel plots were used. The results of the meta-analysis were visualized as a forest plot representing the prevalence estimates of each study. Heterogeneity was also analyzed using the I2, Chi2, and Tau2 statistics. A high level of I2 and Chi2 was obtained among studies, which provides evidence of notable heterogeneity between studies. The results of current study revealed that the highest prevalence of onychomycosis was related to Mazandaran and Tehran provinces, respectively. As in the literature hypothesized shift in etiologic agents from yeasts to dermatophytes or molds could not be confirmed. Females were affected more frequently than males and in both sexes the highest incidence of infection occurrence was at the ages of >50 years. It seems the highest prevalence of onychomycosis in Mazandaran and Tehran provinces is due to the concentration of specialist doctors and research centers in these two provinces compared with others which leads to more detection and more care of the disease. Therefore, further educational strategies in order to accurate diagnosis in other provinces is necessary to reduce the risk of onychomycosis in Iran.

Species identification and in vitro antifungal susceptibility testing of Aspergillus section Nigri strains isolated from otomycosis patients.

INTRODUCTION: Aspergillus niger is the most commonly reported etiology of otomycosis based on morphological characteristics. This fungus is a member of Aspergillus section Nigri, a set of morphologically indistinguishable species that can harbor various antifungal susceptibility patterns. The aim of this study was to accurately identify and determine the susceptibility pattern of a set of black aspergilli isolated from otomycosis patients. METHODS: Forty-three black Aspergillus isolates from otomycosis patients were identified by using the PCR-sequencing of the ß-tubulin gene. Furthermore, the susceptibility of isolates to three antifungal drugs, including fluconazole (FLU), clotrimazole (CLT) and nystatin (NS), were tested according to CLSI M38-A2. The data were analyzed using the SPSS software (version 15). RESULTS: The majority of isolates were identified as A. tubingensis (32/43, 74.42%) followed by A. niger (11/43, 25.58%). The lowest minimum inhibitory concentration (MIC) values were observed for NS with geometric means (GM) of 4.65µg/mL and 4.83µg/mL against A. tubingensis and A. niger isolates, respectively. CLT showed wide MIC ranges and a statistically significant inter-species difference was observed between A. tubingensis and A. niger isolates (P<0.05). FLU was inactive against both species with GMs>64µg/mL. CONCLUSION: Species other than A. niger can be more frequent as observed in our study. In addition, considering the low and variable activity of tested antifungal drugs, empirical treatment can result in treatment failure. Accurate identification and antifungal susceptibility testing of isolates is, however, recommended.

Evaluation of PCR-reverse line blot hybridization assay for simultaneous identification of medically important saprophytic fungi.

BACKGROUND: In immunocompromised patients suffering from invasive fungal infections, rapid identification of fungal species is important since the appropriate treatment is usually related to the responsible species. We describe here, an assay based on combination of PCR and reverse line blot hybridization (PCR/RLB) for differentiation causative agent of fungal infections. MATERIALS AND METHODS: We performed PCR/RLB assay on 10 reference strains, which include Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, and A. clavatus), Mucor circnelloides, Rhizopus oryzae, Alternaria alternata, Cladosporium herbarum, and Fusarium solani. Besides, twenty-two clinical specimens from patients with proven fungal infections were analyzed for the identification of species. The obtained results were then compared with the results of culture and sequence analysis. RESULTS: The fungal species-specific oligonucleotide probes were able to distinguish between all species represented in this study with the exception of cross-reactivity between A. niger and A. fumigatus species. Two specimens, which were represented as mixed fungi in culture, were identified properly by this method. Results of the RLB assay were concordant with the culture and ITS sequencing results. CONCLUSION: Our result demonstrate that the RLB assay potentially is suitable for rapid and simultaneous identification of variety fungal pathogens directly from culture as well as from clinical specimens.

Study of skin and nail Candida species as a normal flora based on age groups in healthy persons in Tehran-Iran.

The skin is the body's largest organ that hosts heterogeneous inhabitants. Until now, the diversity of the cutaneous microbiome was mainly investigated for bacteria and there is a little information about the skin fungal flora. Also, among skin fungal flora, Candida is found as a main member whose distribution is affected by sex, age, climate. In this study, differences in Candida community structure associated with 9 different skin sites of 238 healthy people during 10 months from July to March 2016, are described. These subjects were divided by age into 4 groups: infants, children, adults and geriatrics. The collected samples were examined by culture on Sabouraud Chloramphenicol Agar and CHROM-agar Candida. For precise identification of species ITS1-5. 8S-ITS2 rDNA regions were sequenced where needed. The frequency of Candida species was significantly different between age groups. The most Candida isolations were related to the elderly age group and the fewest in the infants. C. parapsilosis virtually, was the predominant isolated species in all age groups. This study showed no statistically significant effect of the subject's sex on Candida population resident on human skin surface.

Green synthesis of silver nanoparticles: Advantages of the yeast Saccharomyces cerevisiae model.

BACKGROUND AND PURPOSE: Microorganism-based synthesis of nanostructures has recently been noted as a green method for the sustainable development of nanotechnology. Nowadays, there have been numerous studies on the emerging resistant pathogenic bacteria and fungal isolates, the probable inability of bacteria and fungi to develop resistance against silver nanoparticles' (SNPs) antibacterial, antifungal, antiviral and, particularly antibacterial activities. In this study, we aim to use the yeast Saccharomycescerevisiae model for synthesis of SNPs and to investigate its antifungal activity against some isolates of Candidaalbicans. MATERIALS AND METHODS: A standard strain of S.cerevisiae was grown in liquid medium containing mineral salt; then, it was exposed to 2 mM AgNO3. The reduction of Ag+ ions to metal nanoparticles was virtually investigated by tracing the color of the solution, which turned into reddish-brown after 72 hours. Further characterization of synthesized SNPs was performed afterwards. In addition, antifungal activity of synthesized SNPs was evaluated against fluconazole-susceptible and fluconazole-resistant isolates of Candidaalbicans. RESULTS: The UV-vis spectra demonstrated a broad peak centering at 410 nm, which is associated with the particle sizes much less than 70 nm. The results of TEM demonstrated fairly uniform, spherical and small in size particles with almost 83.6% ranging between 5 and 20 nm. The zeta potential of SNPs was negative and equal to -25.0 (minus 25) mv suggesting that there was not much aggregation. Silver nanoparticles synthesized by S.cerevisiae, showed antifungal activity against fluconazole-susceptible and fluconazole-resistant Candida albicans isolates, and exhibited MIC90 values of 2 and 4 µg/ml, respectively. CONCLUSION: The yeast S. cerevisiae model demonstrated the potential for extracellular synthesis of fairly monodisperse silver nanoparticles.