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Sporotrichosis is a global subcutaneous fungal infection caused by the Sporothrix schenckii complex. Sporotrichosis is an uncommon infection in Iran, and there have been no phenotypic, molecular typing or antifungal susceptibility studies of Sporothrix species. This study aimed to identify nine Iranian isolates of the S. schenckii complex to the species level using colony morphology, carbohydrate assimilation tests, and PCRsequencing of the calmodulin gene. The antifungal susceptibilities of these Sporothrix isolates to five antifungal agents (amphotericin B (AMB), voriconazole (VRC), itraconazole (ITC), fluconazole (FLC), and terbinafine (TRB)) were also evaluated according to the M27-A3 and M38-A2 protocols of the Clinical and Laboratory Standards Institute for yeast and mycelial phases, respectively. Five of seven clinical isolates were identified as S. schenckii, and two clinical and two environmental isolates were identified as S. globosa. This is the first report of S. globosa in Iran. There was significant agreement (73%) between the results of the phenotypic and genotypic identification methods. TRB and ITC were the most effective antifungals against the Sporothrix isolates. The minimum inhibitory concentration (MIC) values of TRB for the yeast and mycelial phases of S. schenckii differed significantly. There was also a significant difference in the minimum fungicidal concentration (MFC) values of AMB and TRB for the two phases. Considering the low efficacy of VRC and FLC and the wide MIC ranges of AMB (1–16μg/ml and 1–8μg/ml for yeast and mycelial forms, respectively) observed in the present study, in vitro antifungal susceptibility testing should be performed to determine appropriate therapeutic regimens. [ABSTRACT FROM AUTHOR]

Acquired azole resistance in opportunistic fungi causes severe clinical problems in immunosuppressed individuals. This study investigated the molecular mechanisms of azole resistance in clinical isolates of Candida glabrata. Six unmatched strains were obtained from an epidemiological survey of candidiasis in immunocompromised hosts that included azole and amphotericin B susceptible and azole resistant clinical isolates. Candida glabrata CBS 138 was used as reference strain. Antifungal susceptibility testing of clinical isolates was evaluated using Clinical and Laboratory Standards Institute (CLSI) methods. Complementary DNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) technology, semiquantitative RT-PCR, and sequencing were employed for identification of potential genes involved in azole resistance. Candida glabrata Candida drug resistance 1 (CgCDR1) and Candida glabrata Candida drug resistance 2 (CgCDR2) genes, which encode for multidrug transporters, were found to be upregulated in azole-resistant isolates (≥2-fold). Fatty acid activator 1 (FAA1) gene, belonging to Acyl-CoA synthetases, showed expression in resistant isolates ≥2-fold that of the susceptible isolates and the reference strain. This study revealed overexpression of the CgCDR1, CgCDR2, and FAA1 genes affecting biological pathways, small hydrophobic compounds transport, and lipid metabolism in the resistant clinical C.glabrata isolates. [ABSTRACT FROM AUTHOR]

Background Aspergillus flavus is intensively studied for its role in infecting crop plants and contaminating produce with aflatoxin, but its role as a human pathogen is less well understood. In parts of the Middle East and India, A. flavus surpasses A. fumigatus as a cause of invasive aspergillosis and is a significant cause of cutaneous, sinus, nasal and nail infections. Methods A collection of 45 clinical and 10 environmental A. flavus isolates from Iran were analysed using Variable-Number Tandem-Repeat (VNTR) markers with MICROSAT and goeBURST to determine their genetic diversity and their relatedness to and clinical and environmental A. flavus isolates from Australia. Phylogeny was assessed using partial β-tubulin and calmodulin gene sequencing, and mating type was determined by PCR. Antifungal susceptibility testing was performed on selected isolates using a reference microbroth dilution method. Results There was considerable diversity in the A. flavus collection, with no segregation on goeBURST networks according to source or geographic location. Three Iranian isolates, two from sinus infections and one from a paranasal infection grouped with Aspergillus minisclerotigenes, and all produced B and G aflatoxin. Phylogenic analysis using partial β- tubulin and calmodulin sequencing confirmed two of these as A. minisclerotigenes, while the third could not be differentiated from A. flavus and related species within Aspergillus section flavi. Based on epidemiological cut-off values, the A. minisclerotigens and A. flavus isolates tested were susceptible to commonly used antifungal drugs. Conclusions This is the first report of human infection due to A. minisclerotigenes, and it raises the possiblity that other species within Aspergillus section flavi may also cause clinical disease. Clinical isolates of A. flavus from Iran are not distinct from Australian isolates, indicating local environmental, climatic or host features, rather than fungal features, govern the high incidence of A. flavus infection in this region. The results of this study have important implications for biological control strategies that aim to reduce aflatoxin by the introduction of non-toxigenic strains, as potentially any strain of A. flavus, and closely related species like A. minisclerotigenes, might be capable of human infection. [ABSTRACT FROM AUTHOR]

Due to the epidemiological alteration in distribution of Candida species as well as significant increasing trend of either intrinsic or acquired in resistance of some of these fungi, the precise identification of Candida species is necessary for effective antifungal therapy and also for prevention of nosocomial infections. PCR-RFLP method is indicated to be a reliable, rapid and simple technique which is able to differentiate the Candida species. In the present study, we applied this method to evaluate the distribution of Candida species in patients affected with cutaneous candidiasis in the Guilan province. 896 clinical cutaneous samples were collected from different parts of skin and nail of suspected patients referred to clinical centers all over the Guilan province during 24 months. Samples were examined directly with 15% KOH and cultured on fungal specific media. Genomic DNA was extracted and the restriction enzyme Msp1 was applied for polymorphism analysis. Totally, 47 yeast strains were successfully isolated from different clinical samples and identified by conventional as well as PCR-RFLP methods. The results indicated that Candida albicans (36.17%) was the most frequent species followed by C. parapsilosis (25.53%), C. tropicalis (19.14%), C. guilliermondii (14.89%), C. famata (2.12%) and C. krusei (2.12%). Female finger nails were the most common location to be affected by Candida species. In conclusion, PCR-RFLP method was successfully used for recognition of clinical Candida species within the Guilan province and obtained results revealed C. albicans as the predominant causative agent of cutaneous candidiasis. However, distribution of other Candida species did not completely consist with the reported distribution of Candida species in other parts of Iran with different climate to the Guilan province. [ABSTRACT FROM AUTHOR]

Presently appearance of resistance to antifungal agents among Aspergillus species is dramatically increasing. The objective of this study was to look at the in vitro activities of antifungal drugs against Iranian clinical (from nail, bronchoalveolar lavage, paranasal sinus) isolated A. flavus strains. The susceptibility of 45 aflatoxigenic and non-aflatoxigenic Aspergillus flavus strains were evaluated to six antifungal agents (caspofungin, itraconazole, amphotericin B, ketoconazole, fluconazole, nystatin) using CLSI M38-A2 broth microdilution method. The results indicated that 57.1%, 28.6% of aflatoxigenic and 25.8%, 6.5% of nonaflatoxigenic isolates were susceptible to caspofungin, amphotericin B respectively. All isolates but one aflatoxigenic strain were sensitive to ketoconazole. All 45 strains showed to be resistant to nystatin. Also 64.28%, 92.9% of aflatoxigenic and 64.51%, 100% of non-aflatoxigenic isolates were resistant to fluconazole and itraconazole in ranking order. There was no statistically significant difference between the susceptibilities of aflatoxigenic and non-aflatoxigenic strains of A. flavus to tested antifungal agents. [ABSTRACT FROM AUTHOR]

Background: Different studies have shown that despite the expanding number of antifungal agents, death rate caused by Aspergillus species has been increased during the recent decades due to drug-resistance occurrence, increased minimum inhibitory concentration (MIC) and cross-resistance among the isolated species. Regarding the lack of effective response to conventional treatments and antifungal susceptibility patterns of the most common isolated Aspergillus species, this study was undertaken to draw a clearer picture in the Iranian setting. Methods: During 13 months from September 2009 to October 2010, 50 clinically isolated Aspergillus cases were identified based on the method described by Klich (2002) and their morphological features. Subsequently, their susceptibility test was carried out according to NCCLS- M38A broth microdilution method. Results: We found that 7.5% of the isolated A. flavus with an MIC>2 μg/ml to amphotericin B were probably clinically resistant types, and 25% of them with an MIC<8 μg/ml to itraconazole were less sensitive isolated species. The isolates were less sensitive to voriconazole too. The MIC range of 9 strains of A. niger and the MIC of one strain of A. fumigatus had increased to all the three medications in comparison with similar foreign studies. Conclusion: In this study we found that the MICs of most isolates were in the range of the reference strains and the MICs of some isolates were in the range of similar foreign studies. In some significant cases, the MICs were beyond the known ranges showing the lower sensitivity of Iranian isolates and their increased MIC patterns. [ABSTRACT FROM AUTHOR]

Background: Infections caused by opportunistic yeasts such as Candida species, Trichosporon, Rhodotorula and Saccharomyces have increased in immunocompromised patients and their identification is crucial as intrinsic and acquired resistance of some yeast species to antifungal agents are on the rise. The aim of this study was to identify the organisms to the species level in order to suggest accurate and effective antifungal therapies. Methods: In this study that carried out in Tehran, Iran in 2009, 200 patients with yeast infection were medically examined and clinical specimens were prepared for direct examination and culture on Sabouraud dextrose agar. Subsequently, the isolated yeast colonies were identified using various tests including culture on Corn Meal agar with Tween 80, CHROMagar Candida and casein agar. For the definite identification of organisms some biochemical tests were done based on carbohydrate assimilation by RapID Yeast Plus System kit, and, finally, a molecular method, PCR-RFLP, using Hpa II enzyme, was performed for the remaining unknown yeast species. Results: A total of 211 yeast isolates were identified in 200 patients with yeast infections. The most frequent isolated yeasts were Candida albicans, 124 (58.77%), followed by Candida parapsilosis, 36 (17.06%), Candida tropicalis, 17 (8.06%), Candida glabrata, 13 (6.16%), Candida krusei, 8 (3.79%), Candida guilliermondii, 2 (0.96%), Trichosporon, 3 (1.14%), Rhodotorula, 1 (0.47%), Saccaromyces cerevisiae, 1 (0.47%) and other yeast species, 6 (2.84%). Conclusion: Nail candidiasis was the most prevalent type of yeast infection in the patients and Candida albicans was the most frequent isolated species from all clinical specimens. [ABSTRACT FROM AUTHOR]

Introduction: Candiduria is common in the hospitalized patients. This study aimed to quantify interleukin (IL)-17 and IL-22 levels in urine of candiduric patients.Materials and Methods: A case-control study was conducted on inpatients at Hashemi Nejad Kidney Center. Thirty-four patients were identified with Candida species in their urine samples (> 103 colony-forming units per milliliter and presence of Candida species only). Urine samples with concomitant infections were excluded. Thirty-four patients with negative direct examination and culture were included as the control patients. Interleulin-17 and IL-22 levels were measured in the lyophilized and nonlyophilized urine. The relevant cytokine titers of the two groups were compared, and the association of cytokine elevation and candiduria was investigated.Results: The majority of the candiduric patients were from the intensive care and urology units of women. Only 4 patients (11.7%) manifested fever and dysuria. Massive leukocyturia was observed in 4 patients. Candida glabrata was the most commonly isolated species (44%). Levels of the urine IL-17 and IL-22 were significantly elevated in the candiduric patients, when compared to the noncandiduric controls. While an increased IL-17 level was significantly associated with candiduria (odds ratio, 1.09; 95% confidence interval, 1.003 to 1.17; P = .04), an increased IL-22 level was not. The results showed that lyophilized urine samples maximized the detection power of urinary cytokines.Conclusions: Our results indicated that direct examination, fungal urine culture, and investigation of urine IL-17 and IL-22 levels are useful tools for diagnosis of Candida urinary tract infection. [ABSTRACT FROM AUTHOR]

Background: Candida parapsilosis is an emergent agent of invasive fungal infections. This yeast is one of the five most widespread yeasts concerned in invasive candidiasis. C. parapsilosis stands out as the second most common yeast species isolated from patients with bloodstream infections especially in neonates with catheter. Recently several reports suggested that its reduced susceptibility to azoles and polyene might become a cause for clinical concern, although C. parapsilosis is not believed to be intensely prone to the development of antifungal resistance., Methods: In the present report, One hundred and twenty clinical isolates of C. parapsilosis complex were identified and differentiated by using PCR-RFLP analysis. The isolates were then analyzed to determine their susceptibility profile to fluconazole (FLU), itraconazole (ITC) and amphotericin B. The minimum inhibitory concentration (MIC) results were analyzed according to the standard CLSI guide., Results: All of isolates were identified as C. parapsilosis. No C. metapsilosis and C. orthopsilosis strains were found. Evaluation of the antifungal susceptibility profile showed that only three (2.5%) C. parapsilosis were resistant to fluconazole, three (2.5%) C. parapsilosis were resistant to itraconazole and two (1.7%) C. parapsilosis were amphotericin B resistant., Conclusion: Profiles in clinical isolates of C. parapsilosis can provide important information for the control of antifungal resistance as well as distribution and susceptibility profiles in populations.

Background: The aim of this study was to detect fungi in atherosclerotic plaques and investigate their possible role in atherosclerosis., Methods: Coronary atherosclerotic plaques specimen were obtained from patients with atherosclerosis. Direct examination, culture, histopathology study, PCR and sequencing were performed to detect/identify the mycotic elements in the plaques. Age, sex, smoking, obesity, hypertension, hyperlipidemia, family history of heart diseases and diabetes were considered and data were analyzed using Chi Square test by SPSS version 15., Results: A total of 41 specimens were analyzed. Direct examination for fungal elements was negative in all cases but in culture only one specimen grew as a mold colony. The presence of fungal elements were confirmed in 6 and 2 tissue sections stained by Gomori methenamine silver and Hematoxylin and Eosin methods, respectively. Using PCR, 11 cases were positive for fungi. The DNA sequence analysis of six positive specimens which were randomly selected revealed fungi as Candida albicans (n=3), Candida guilliermondii (n=2) and Monilia sp. (n=1)., Conclusion: A significant association between the presence of fungi in atherosclerotic plaques and severity of atherogenesis and atherosclerotic disease was not found. This could be due to limited numbers of patients included in our study. However, the presence of fungal elements in 26.8% of our specimens is considerable and the results does not exclude the correlation between the presence of fungi with atherosclerosis and coronary artery disease.