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Objectives: To investigate the occurrence of Trichosporon asahii fungemia among critically ill COVID-19 patients., Methods: From 1 July to 30 September 2020, cases of T asahii fungemia (TAF) in a Brazilian COVID-19 referral centre were investigated. The epidemiology and clinical courses were detailed, along with a mycological investigation that included molecular species identification, haplotype diversity analysis and antifungal susceptibility testing., Results: Five critically ill COVID-19 patients developed TAF in the period. All five patients had common risk conditions for TAF: central venous catheter at fungemia, previous exposure to broad-spectrum antibiotics, prior echinocandin therapy and previous prolonged corticosteroid therapy. The average time of intensive care unit hospitalisation previous to the TAF episode was 23 days. All but one patient had voriconazole therapy, and TAF 30-day mortality was 80%. The five T asahii strains from the COVID-19 patients belonged to 4 different haplotypes, mitigating the possibility of skin origin and cross-transmission linking the 5 reported episodes. The antifungal susceptibility testing revealed low minimal inhibitory concentrations for azole derivatives., Conclusions: Judicious prescription of antibiotics, corticosteroids and antifungals needs to be discussed in critically ill COVID-19 patients to prevent infections by hard-to-treat fungi like T asahii., (© 2021 Wiley-VCH GmbH.)

Background: Trichosporonosis is an emerging fungal infection caused by Trichosporon species, a genus of yeast-like fungi, which are frequently encountered in human infections ranging from mild cutaneous lesions to fungemia in immunocompromised patients. The incidence of trichosporonosis has increased in recent years, owing to higher numbers of individuals at risk for this infection. Although amphotericin B, posaconazole and isavuconazole are generally effective against Trichosporon species, some isolates may have variable susceptibility to these antifungals., Objectives: Herein, we evaluated the species distribution, genetic diversity and antifungal susceptibility profiles of Trichosporon isolates in Iran., Methods: The yeasts were identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Phylogenetic analysis was performed based on amplified fragment length polymorphism (AFLP). The in vitro susceptibilities of eight antifungal agents were analysed using the Clinical and Laboratory Standards Institute broth microdilution methods., Results: The isolates belonged to the species T asahii (n = 20), T japonicum (n = 4) and T faecale (n = 3). A dendrogram of the AFLP analysis demonstrated that T asahii and non-asahii Trichosporon strains (T japonicum and T faecale) are phylogenetically distinct. While voriconazole was the most active agent (GM MIC = 0.075 μg/ml), high fluconazole MICs (8 μg/ml) were observed for a quarter of Trichosporon isolates. The GM MIC value of amphotericin B for T asahii and non-asahii Trichosporon species was 0.9 μg/ml., Conclusions: The distribution and antifungal susceptibility patterns of the identified Trichosporon species could inform therapeutic choices for treating these emerging life-threatening fungi., (© 2021 Wiley-VCH GmbH.)

Background: Trichosporonosis is a rare invasive infection in humans mainly due to Trichosporon asahii, and especially recovered from patients having haematological malignancy. Since 2012, IGS1 region sequencing is used as a genotyping method to distinguish isolates, with high frequency of one haplotype worldwide and a geographic specificity for some haplotypes., Objectives: We compared the IGS1 genotyping method and whole genome sequencing (WGS) to study the relationship between clinical isolates involved in two grouped cases in France., Methods: IGS1 sequencing and antifungal susceptibility testing were performed for 54 clinical isolates. Clinical data for 28 isolates included in surveillance programs were analysed. Whole genome was sequenced for 32 clinical isolates and the type strain., Results: All isolates were intrinsically resistant to flucytosine, while voriconazole had the most potent in vitro activity. The majority of the isolates was recovered from patients with haematological malignancies (42.86%), with a high proportion of children (<15 yrs-old, 32.14%) and a high mortality rate at three months (46.15%). Based on the WGS analysis, isolates exhibiting IGS1 haplotype 1, 3 and 7 belonged to different clades. Five isolates recovered during the first grouped cases had the same IGS1 haplotype and shared 99% of SNPs similarity. For the second grouped cases, four isolates had 98.7% of SNPs similarity while the isolate recovered 4 years earlier was totally unlinked., Conclusions: We confirmed the usefulness of IGS1 sequencing for grouped cases infection of T. asahii. We underlined its limitation for the study of population structure and the utility of WGS analysis for the study of epidemiologically unrelated isolates., (© 2020 Blackwell Verlag GmbH.)

Trichosporon is a yeast-like basidiomycete, a conditional pathogenic fungus that is rare in the clinic but often causes fatal infections in immunocompromised individuals. Trichosporon asahii is the most common pathogenic fungus in this genus and the occurrence of infections has dramatically increased in recent years. Here, we report a systematic literature review detailing 140 cases of T. asahii infection reported during the past 23 years. Statistical analysis shows that T. asahii infections were most frequently reported within immunodeficient or immunocompromised patients commonly with blood diseases. Antibiotic use, invasive medical equipment and chemotherapy were the leading risk factors for acquiring infection. In vitro susceptibility, clinical information and prognosis analysis showed that voriconazole is the primary drug of choice in the treatment of T. asahii infection. Combination treatment with voriconazole and amphotericin B did not show superiority over either drug alone. Finally, we found that the types of infections prevalent in China are significantly different from those in other countries. These results provide detailed information and relevant clinical treatment strategies for the diagnosis and treatment of T. asahii infection.

Trichosporon species are some of the most common pathogenic yeasts in Asia, and many are resistant to echinocandin antifungal drugs. Effective treatment of fungal infections requires the selection of appropriate antifungals and the accurate identification of the causal organism. However, in histopathological specimens Trichosporon spp. are often misidentified as Candida species due to morphological similarities. In situ hybridization (ISH) is a useful technique for identifying fungal species in formalin-fixed and paraffin-embedded (FFPE) tissue sections. Although many novel probes for ISH are available, the practical use of ISH for identification of fungi remains limited, in part due to the lack of adequate verifications. We conducted a two-center retrospective observational study in which the ISH technique was used to differentiate Trichosporon spp. and C. albicans in FFPE tissue from autopsy specimens. The study included 88 cases with blood stream yeast infection without Cryptococci extracted from 459 autopsy files of cases with proven invasive fungal infection (IFI). Positive signals for the Trichosporon spp. protein nucleic acid (PNA) probe and C. albicans PNA probe were seen for 7 and 35 cases, respectively, whereas the remaining 46 were negative for both. For the Trichosporon spp.- positive specimens, 5/7 were reported as candidiasis in autopsy records. Our results suggested that accurate histological identification of fungal infections remains challenging, but ISH may be a suitable approach to support histological findings. In addition, this retrospective study suggested that trichosporonosis may have high prevalence among cases of bloodstream yeast infections in Japan., (© The Author(s) 2019. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Recently, Trichosporon taxonomy has been reevaluated and new genera of the Trichosporonaceae family have been described. Here, 26 clinical isolates were submitted for identification via sequencing of the intergenic space 1 (IGS1) region, genotyping, and investigation of virulence factors. Antifungal susceptibility was determined using the CLSI broth microdilution method for fluconazole (FLC), itraconazole (ITC), and amphotericin B (AMB). Of these, 24 isolates were identified, including 12 T. asahii, 4 T. inkin, 3 T. faecale, 1 T. coremiiforme, 1 T. japonicum, 2 Cutaneotrichosporon dermatis (formerly T. dermatis), and 1 Apiotrichum mycotoxinivorans (formerly T. mycotoxinivorans). Species-level identification of 2 isolates was not successful; they were described as Trichosporon sp. We observed optimal colonial development at 35-40 °C. Lipase was the major extracellular enzyme produced (100%); caseinase was not produced (0%). Biofilms were produced by all isolates (classified as low). High AMB minimum inhibitory concentration (MIC) was observed, with all strains resistant. Fluconazole was the most active drug among the antifungals tested. However, high MICs for FLC were observed in C. dermatis and A. mycotoxinivorans species, which also showed resistance to ITC and AMB. This study, conducted in the Northern region of Brazil, identified 5 Trichosporon species along with C. dermatis and A. mycotoxinivorans and demonstrated their pathogenic potential through their ability to produce important virulence factors. This may contribute to our understanding of the epidemiology and factors related to the pathogeneses of species in the Trichosporonaceae family.

Introduction: Over the past four decades, there has been an increase in the number of fatal opportunistic invasive trichosporonosis cases especially in immunocompromised hosts., Objective: The objective of the study is to evaluate the epidemiological, clinical details and antifungal susceptibility pattern of the patients with Trichosporon infections., Materials and Methods: Twenty-four clinical isolates of Trichosporon species isolated from blood, samples, pleural fluid and nail were included in this study, over a period of 12 years (2005-2016) in a tertiary hospital in North India. The isolates were characterised phenotypically and few representative isolates were sequenced also. The minimum inhibitory concentration (MIC) was determined as per Clinical and Laboratory Standards Institute, 2012., Results: Trichosporon spp. from blood culture (57.78%), nail (37.5%) and pleural fluid (4.17%). On phenotypic tests, 79.16% of the isolates were Trichosporon asahii, followed by Trichosporon dermatis (8.33%), Trichosporon japonicum (4.17%), Trichosporon ovoides (4.17%) and Trichosporon mucoides (4.17%). The MIC range of Trichosporon species from invasive infections were fluconazole (0.06-256 μg/ml), amphotericin B (0.125-16 μg/ml), voriconazole (0.0616-8 μg/ml), posaconazole (0.0616-32 μg/ml) and caspofungin (8-32 μg/ml). The isolates from superficial infection were resistant to fluconazole (0.06-256 μg/ml) and itraconazole (0.125-32 μg/ml), all were susceptible to ketoconazole and while only two were resistant to voriconazole (0.25-4 μg/ml)., Conclusion: T. asahii was the most common isolate. Disseminated trichosporonosis is being increasingly reported worldwide including India and represents a challenge for both diagnosis and species identification. Prognosis is limited, and antifungal regimens containing triazoles appear to be the best therapeutic approach. In addition, accurate identification, removal of central venous lines and voriconazole-based treatment along with control of underlying conditions were associated with favourable outcomes., Competing Interests: None

Aim: Trichosporon species are the major emerging opportunistic pathogen in immunocompromised patients. Its diverse refractoriness to conventional antifungal drugs and association with high mortality rate is worrisome. The present study aims to determine the risk factors, treatment outcome and antifungal susceptibility pattern of Trichosporon species in blood stream infections., Material and Methods: All patients with blood culture positive for Trichosporon species from January 2012 to August 2016 at PD Hinduja National Hospital and research centre were evaluated retrospectively. Species identification and antifungal susceptibility by broth microdilution method for various drugs was determined using Vitek2 compact automated system., Results: 12 patients were found to have Trichosporon blood stream infection. 9 isolates that were speciated all were T. asahii. All patients had central venous catheter and received prior antibiotics. Overall mortality rate was 50%., Conclusion: Higher mortality was associated with central venous catheter and voriconazole should be used as drug of choice for treatment. Identification of Trichosporon species along with its sensitivity and proper treatment of patients is of utmost importance., (© Journal of the Association of Physicians of India 2011.)

A total of 133 clinical Trichosporon isolates were collected in the National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) program in 2009 to 2016. Accurate identification was performed by sequencing of the intergenic spacer 1 (IGS1) region. Among these isolates, Trichosporon asahii (108 isolates [81.2%]) was the leading species, followed by Trichosporon dermatis (7 isolates [5.3%]), Trichosporon asteroides (5 isolates [3.8%]), Trichosporon inkin (5 isolates [3.8%]), Trichosporon dohaense (3 isolates [2.3%]), and 1 isolate (0.7%) each of Trichosporon faecale , Trichosporon jirovecii , Trichosporon mucoides , Trichosporon coremiiforme , and Trichosporon montevideense Both the Vitek mass spectrometry (MS) (bioMérieux, Marcy l'Etoile, France) and Bruker Biotyper MS (Bruker Daltonics GmbH, Germany) platforms gave high levels (>97.5%) of correct identification when the species were present in the database. The geometric mean (GM) of amphotericin B MICs for T. asahii was 2-fold higher than that for non- asahii Trichosporon High fluconazole MICs (≥8 μg/ml) were observed for 25% of T. asahii isolates (27/108 isolates) and 16% of non- asahii Trichosporon (4/25 isolates) isolates. Itraconazole MICs were ≤0.5 μg/ml for 89.5% of the isolates. Voriconazole was the most potent antifungal agent in vitro , with a GM of 0.09 μg/ml. Genotyping of the isolates using IGS1 sequence alignment revealed that genotype 1 was most common (41.7%), followed by genotype 4 (31.5%), genotype 3 (23.1%), genotype 5 (0.9%), genotype 6 (0.9%), and genotype 7 (1.8%). Our data on species distribution, genotypes, and antifungal susceptibilities may contribute to a better understanding of the epidemiology of invasive Trichosporon infections throughout China., (Copyright © 2019 American Society for Microbiology.)

We report the first two cases of Trichosporon mycotoxinivorans infections in Latin America. We also conducted a literature review and a microbiological investigation, including that of clinical and environmental isolates. A 30-year-old man with chronic renal failure had disseminated infection after dialysis and a 15-year-old boy with cystic fibrosis (CF) had pulmonary exacerbations with positive respiratory samples. A review of the relevant literature revealed that deep-seated infections were related to immunosuppression or invasive devices, while most of the CF patients showed a decline in lung function after positive cultures. Phylogenetic analyses revealed three distinct circulating genotypes. MALDI-TOF mass spectrometry analysis showed similar spectral profiles and correctly identified all strains/isolates. Biofilm production was documented in a bloodstream isolate and biofilm-producing cells showed high minimum inhibitory concentrations against antifungals.

In Asian countries, Trichosporon infection is a well-known disease in Japan. In India, the infection is increasingly recognised. The study was conducted to characterise the clinical Trichosporon isolates from India by phenotypic and molecular techniques. A total of 31 Trichosporon clinical isolates, recovered from patients of 14 hospitals across India were sequenced (ITS and IGS1 regions of rDNA). In vitro drug susceptibility testing of the isolates was performed against amphotericin-B, fluconazole, itraconazole, voriconazole and posaconazole. IGS1, rather than ITS sequences, correctly identified the isolates: Trichosporon asahii, 20; Trichosporon ovoides, 3; Trichosporon inkin, 2; Trichosporon asteroides, 1; Trichosporon mucoides, 1; Trichosporon loubieri, 1; Trichosporon debeurmannianum, 1; and Trichosporon dermatis, 1. Trichosporon asahii genotype III was the most common type, followed by genotype I and VII. Both these targets did not help to identify one Trichosporon to the species level. Trichosporon debeurmannianum, T. dermatis and T. asteroides were isolated for the first time from a human disease in India. The minimum inhibitory concentrations for voriconazole and posaconazole were within effective range. The study highlights the presence of wide range of Trichosporon species causing infection in India. Voriconazole or posaconazole may be the better drugs to treat such patients., (© 2016 Blackwell Verlag GmbH.)

Summer-type hypersensitivity pneumonitis (SHP) is the most common form of pneumonitis in Japan; it accounts for 74% of all cases. It has been reported that 19.5-23.8% of SHP cases occur in families who live in the same house. We present our SHP cases and review 50 familial cases in 23 families that were reported in Japan (including our own) and 48 cases that were previously described in 22 articles published between January 1982 and October 2011. To the best of the authors' knowledge, this is the first review article in English to document the familial occurrence of SHP in Japan.

Objective: To evaluate the incidence of urinary tract infections due to Trichosporon spp. in an intensive care unit., Methods: This descriptive observational study was conducted in an intensive care unit between 2007 and 2009. All consecutive patients admitted to the intensive care unit with a confirmed diagnosis were evaluated., Results: Twenty patients presented with urinary tract infections due to Trichosporon spp. The prevalence was higher among men (65%) and among individuals > 70 years of age (55%). The mortality rate was 20%. The average intensive care unit stay was 19.8 days. The onset of infection was associated with prior use of antibiotics and was more frequent in the fall and winter., Conclusion: Infection due to Trichosporon spp. was more common in men and among those > 70 years of age and was associated with the use of an indwelling urinary catheter for more than 20 days and with the use of broadspectrum antibiotics for more than 14 days. In addition, patients with urinary infection due to Trichosporon spp. were most often hospitalized in intensive care units in the fall and winter periods.

Trichosporon asahii has been recognized as an emerging opportunistic agent for invasive infections, mainly in immunocompromised patients. Urinary tract infections by this pathogen may also occur, especially in patients with urinary obstruction or those undergoing vesical catheterization and antibiotic treatment. Many outbreaks of Trichosporon spp. have been detected after urinary catheter manipulations. We report the molecular-epidemiological characterization of T. asahii in our institution using the DiversiLab system for the molecular strain typing and compare three different methods for susceptibility testing. Our results present T. asahii as an emergent pathogen in elderly patients with urinary drainage devices that can be adequately treated with triazoles, with voriconazole being the most active. Broth dilution and Vitek 2 had good concordance, while Etest showed more discrepancies. In addition, the DiversiLab system for clonal strain typing may be a useful tool for fast and accurate management of nosocomial outbreaks.

Among 32 Trichosporon asahii isolates collected in four rounds of the Taiwan Surveillance of Antimicrobial Resistance of Yeasts (TSARY) studies, conducted in 1999, 2002, 2006, and 2010, five different intergenic spacer 1 (IGS1) genotypes were detected. Genotype 1 was the most common (43.8%), followed by genotypes 3 (28.1%), 7 (12.5%), 5 (9.4%), and 4 (6.3%). Interestingly, genotype 7 was more prevalent in Taiwan than in other areas (P = 0.01); while we did not find a significant association between IGS1 genotype and susceptibility to antifungal drugs, we did note that the majority of isolates of T. asahii were susceptible to both fluconazole and voriconazole, consistent with previous reports. A higher proportion of isolates (P = 0.05) collected in 2010 (4/12, 33.3%) had high amphotericin B MICs (≥ 2 mg/l) than those collected in the previous three TSARYs (1/21, 5%). Hence, the new data of genotypes and drug susceptibilities in the present study may contribute to the epidemiology of T. asahii.

Trichosporon species cause systemic, mucosa associated and superficial infections which include white piedra. Disseminated fungal infections due to Trichosporon species have increased in the recent years. Hematologic malignancy, cytotoxic chemotherapy, and organ transplantation are the main risk factors for disseminated Trichosporon infections. Two most common species that cause the disseminated Trichosporon infections are Trichosporon asahii and Trichosporon mucoides. Diagnosis and treatment of Trichosporon infections are difficult. Invasive trichosporonosis caused by T.asahii has a high mortality rate and a very poor prognosis. Fungicidal activity of amphotericin B against T.asahii isolates is inadequate. For echinocandin group of drugs, high minimum inhibitory concentration (MIC, µg/ml) values are obtained. Currently, triazole antifungal agents are the preferred drugs for the treatment of Trichosporon infections. In this review article general characteristics of T.asahii and its infections were summarized.

The presence of Candida in urine presents a therapeutic challenge for the physician as it is often asymptomatic, and management guidelines have not been clearly laid down on this issue. The presence of Candida in urine may represent contamination of clinical sample, actual colonization of the lower urinary tract or may be a true indicator of invasive infection of lower and/or upper urinary tract. In a clinical setting like the ICU, multiple risk factors for Candida colonization may be present in the same patient, thereby increasing the chances of candiduria, manifold. In the present study on 80 patients in ICU, high rate of Candida colonization (57.5%) was found in urine samples of ICU patients with C. tropicalis (57.3%) being the predominant species. We also isolated 8 strains of Trichosporon species, all of these presented as a mixed infection along with Candida species. Among the various risk factors studied, urinary catheterization and previous antibiotic therapy were identified as statistically significant (P value <0.05). The minimum inhibitory concentration of the isolates was determined for amphotericin B, fluconazole and itraconazole by E-test. Most of the isolates were susceptible to amphotericin B. The C. parapsilosis strains did not show any drug resistance; however, resistance to fluconazole was observed 18.6, 27.27, 50 and 25% in C. tropicalis, C. albicans, C. glabrata and Trichosporon species, respectively.