Current knowledge of Trichosporon spp. and Trichosporonosis

Whole-Genome Sequencing and Comparative Genomic Analysis of Three Clinical Bloodstream Infection Isolates of Trichosporon austroamericanum

Trichosporon austroamericanum is a recently described yeast species related to Trichosporon inkin and exclusively isolated from clinical specimens. However, its genomic features and pathogenic potential remain poorly understood. In this study, we performed whole-genome sequencing on three blood-derived isolates from patients with invasive fungal infections and comparative analyses with 13 related Trichosporon species. The three isolates yielded high-quality assemblies of 9-10 scaffolds (~21 Mb), facilitating reliable comparisons. While most species had comparable genome sizes, Trichosporon ovoides, Trichosporon coremiiforme, and Cutaneotrichosporon mucoides displayed large, fragmented genomes, suggestive of polyploidy. ANI analysis and phylogenetic trees based on ANI and single-copy orthologs supported the classification of T. austroamericanum as a distinct clade with moderate intraspecific divergence. Using the Galleria mellonella, a model for fungal pathogenicity, all T. austroamericanum strains reduced larval survival, and NIIDF 0077300 exhibited virulence comparable to T. asahii and greater than T. inkin. To explore the gene-level differences associated with pathogenicity, we performed ortholog analysis based on single-copy genes. This revealed a unique Zn(II)2Cys6-type transcription factor gene (OG0010545) present only in NIIDF 0077300 and T. asahii. These findings highlight the genomic diversity and infection-associated traits of T. austroamericanum, providing a framework for future functional studies.

Transcriptomics Uncovers Key Genes for Photodynamic Killing on Trichosporon asahii Biofilms

BACKGROUND

The escalating threat of antifungal resistance stemming from Trichosporon asahii (T. asahii) biofilms necessitates the pursuit of innovative therapeutic strategies. Among these approaches, 5-aminolevulinic acid (ALA) photodynamic therapy (PDT), an emerging therapeutic modality, has exhibited promising potential in eradicating T. asahii biofilms.

METHODS

The inhibitory activity was evaluated by confocal laser scanning microscopy. To delve deeper into the efficacy of ALA-PDT in eliminating T. asahii biofilms, we conducted a comprehensive transcriptional analysis utilizing transcriptome sequencing.

RESULTS

ALA-PDT demonstrated a profound inhibitory effect on the viability of T. asahii biofilms. Our investigation unveiled 2720 differentially expressed genes following exposure to ALA-PDT. Subsequent meticulous scrutiny allowed for the annotation of genes with a ≥ twofold change in transcription, focusing on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways. Particularly noteworthy were the upregulated genes associated with oxidation-reduction processes, oxidoreductase activity, and catalytic activity. Conversely, the downregulated genes were linked to ATP binding, protein phosphorylation, and protein kinase activity. Additionally, we observed a surge in the transcription of genes that may be involved in oxidative stress (e.g., A1Q1_05494) as well as genes that may be involved in morphogenesis and biofilm formation (e.g., A1Q1_04029, A1Q1_01345, A1Q1_08069, and A1Q1_01456) following ALA-PDT treatment.

CONCLUSIONS

Our findings underscore the substantial impact of ALA-PDT on the transcriptional regulation of genes related to oxidative stress, morphogenesis, and biofilm formation, paving the way for novel therapeutic avenues in combating T. asahii biofilms.

In vitro activity of isavuconazole, ravuconazole, and comparison of the Sensititre YeastOne and CLSI broth microdilution methods against clinical isolates of Trichosporon species

This study aimed to evaluate the in vitro activity of isavuconazole and ravuconazole against clinical Trichosporon isolates. Additionally, we assessed the performance of the Sensititre YeastOne (SYO) assay compared to the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) method for antifungal susceptibility testing. A total of 267 Trichosporon clinical isolates were collected from multiple centers in Taiwan between 2008 and 2020. The MIC values for amphotericin B, fluconazole, itraconazole, posaconazole, and voriconazole obtained using the CLSI BMD were compared to those determined using SYO. Among the seven antifungal agents tested using the CLSI BMD method, T. asahii isolates (n = 224) exhibited significantly higher MICs for fluconazole, voriconazole, isavuconazole, and ravuconazole compared to non-T. asahii isolates (n = 43) (p < 0.05). Across all isolates, voriconazole demonstrated the lowest geometric mean (GM) MIC (0.06 mg/L). For T. asahii, the MIC₅₀, MIC₉₀, and GM MICs for posaconazole, isavuconazole, and ravuconazole were within ±1 twofold dilution, while mode MICs showed slightly greater variation (MIC₅₀, MIC₉₀, mode, and GM MICs were 0.25, 0.5, 0.5, and 0.28 mg/L; 0.12, 0.5, 0.12, and 0.17 mg/L; and 0.25, 0.5, 0.25, and 0.21 mg/L, respectively). The consistency of the MIC measurements between the SYO and CLSI BMD methods was assessed for amphotericin B, fluconazole, itraconazole, posaconazole, and voriconazole. The highest agreement within ±1 twofold dilution for T. asahii isolates was observed for posaconazole (94.2%). The essential agreement within ±2 twofold dilutions between both methods for all drugs was >97%. In conclusion, isavuconazole and ravuconazole demonstrated favorable in vitro activity against clinical Trichosporon isolates, while the SYO assay showed good concordance with the CLSI BMD method.IMPORTANCEInvasive infections caused by Trichosporon species pose significant therapeutic challenges, primarily due to their intrinsic resistance to echinocandins and the limited availability of effective treatment options. This study provides essential data on the in vitro activity of newer azoles and comprehensively evaluates the performance and concordance of the Sensititre YeastOne (SYO) and CLSI broth microdilution (BMD) methods. The current study analyzed 267 Trichosporon clinical isolates collected from multicenter settings in Taiwan. Our results demonstrate that both isavuconazole and ravuconazole exhibit favorable in vitro activities against Trichosporon species. For T. asahii, the essential agreement between the SYO and CLSI BMD methods exceeded 97% for all tested antifungal agents, indicating that the SYO method exhibits good concordance for most Trichosporon species. Further investigations are warranted to validate these findings and to assess their clinical implications.

Detection and Identification of Food-Borne Yeasts: An Overview of the Relevant Methods and Their Evolution

The presence of yeasts in food is not unexpected, as they are part of the microbiota of raw materials, employed as starter cultures in numerous fermentation processes, and also play a role in spontaneous fermentation. Nevertheless, they have the potential to induce spoilage, which can lead to significant quality issues, and certain yeasts have the ability to cause infections in humans and animals, posing a food safety risk. The detection of yeasts in food, determination of their cell number, as well as identification and typing, are therefore often tasks during the examination of certain food categories. The methods employed to achieve these objectives are diverse, encompassing both conventional culture-based techniques and more recent, genome-based studies. The objective of this study is to provide a summary article that presents the methods suitable for testing food-derived yeasts. The article will highlight the advantages, disadvantages, and potential difficulties of their applicability. Moreover, a comprehensive review of nucleic acid-based, culture-dependent and culture-independent molecular yeast identification techniques was conducted, encompassing scientific articles from the past five years (2020-2024). The search was based on the Science Direct database using the keywords "yeast and molecular identification and food".

Tenosynovitis caused by Trichosporon asahii in an immunocompetent patient

BACKGROUND

Fungal infections have become a public health problem owingdute to their progressive increase in recent decades and high morbidity rates. Fungal bone and joint infections result from direct inoculation, contiguous infection spread, or hematogenous seeding of organisms. Trichosporon spp. are yeast-like basidiomycetes, with Trichosporon asahii being the most common pathogenic species. This article describes a rare case of tenosynovitis caused by Trichosporon asahii in an immunocompetent patient. Treatment with voriconazole resulted in an excellent clinical response.

Trichosporon species bloodstream infections in a tertiary care hospital in the western region of Saudi Arabia: A 7-year retrospective chart review from 2016 to 2022

Despite advances in medical mycology, invasive Trichosporon spp. infections continue to be associated with high mortality rates. Limited data exist on the risk factors and outcomes of Trichosporon fungemia, particularly in our region. Therefore, this study aims to describe the risk factors, patient characteristics, antifungal susceptibility, and outcome of Trichosporon bloodstream infections at a tertiary care hospital in Saudi Arabia. This was a single-center retrospective chart review that included adult patients ≥ 16 years with positive blood cultures for Trichosporon spp. from January 2016 to December 2022. Descriptive statistics are presented using the mean for continuous variables and the number (percentage) for categorical variables. Ten patients with Trichosporon spp. isolated from blood cultures were eligible for inclusion in this study. The mean age was 58.1 years (range 17-83), with 70% male patients. Additionally, 40% had diabetes mellitus, and 40% had underlying malignancy. Trichosporon asahii was the predominant species in 90% of isolates. All patients had recent broad-spectrum antibiotic use, 80% were exposed to corticosteroids, and all had central venous catheters. One kidney transplant had an early recurrence of Trichosporon spp. fungemia. Four patients were cured of the infection, two were treated with voriconazole monotherapy, and two were treated with a combination of liposomal amphotericin B plus Voriconazole. Thirty-day all-cause mortality was 60%, with three deaths occurring before identification of the isolates. In conclusion, our study reported a predominance of Trichosporon asahii and a mortality rate of 60% in patients with Trichosporon fungemia. Challenges include delayed diagnosis, high mortality, and antifungal resistance, underscoring the need for further research to enhance treatment strategies and patient outcomes.

Inhibition of calcineurin as a strategy for biofilm control: Trichosporon spp. as a case study

Among the opportunistic species related to Invasive Fungal Infections (IFIs), Trichosporon spp. are particularly noteworthy, being responsible for infections with high mortality rates in patients with hematological cancers. Trichosporon spp. are intrinsically resistant to echinocandins and their biofilms are tolerant to polyenes and triazoles. This study investigated the effect of calcineurin inhibition on the development and antifungal tolerance of Trichosporon biofilms. Mature biofilms of T. inkin and T. asahii were treated with Ciclosporin A (CsA) and analyzed for biomass reduction and viability, ultrastructure, and tolerance tolerance to antifungals. Molecular docking studies were performed to understand the attachment of CsA to the calcineurin of T. asahii. CsA was able to significantly reduce both the biomass and metabolic activity of biofilms. Mature biofilms formed in the presence of CsA showed greater susceptibility to antifungals, compared to biofilm growth control. CsA caused structural changes in biofilms. Molecular modeling suggested that CsA can block the active site of the calcineurin A subunit of T. asahii. Calcineurin inhibition seems to be a promising strategy for controlling antifungal-resistant fungal biofilms.

Analyses of hyphal diversity in Trichosporonales yeasts based on fluorescent microscopic observations

In dimorphic yeasts, hyphal growth is primarily associated with infection and mycosis progression, with Trichosporon asahii causing deep-seated mycosis and summer-type hypersensitivity pneumonitis. Magnesium accelerates hyphal growth in T. asahii, leading to multi-septation, vacuolar expansion, and decreased lipid droplet size. However, the commonality of these phenotypes has not been studied in Trichosporonales yeasts. Therefore, to explore whether similar magnesium-induced phenotypes occur across Trichosporonales yeasts, we examined hyphal growth, multi-septation, vacuolar extension, and lipid droplet size and number in 30 species. Cell length increased with magnesium treatment in 13 yeasts: 5 Trichosporon (T. asahii, Trichosporon aquatile, Trichosporon asteroides, Trichosporon coremiiforme, and Trichosporon ovoides), three Apiotrichum (Apiotrichum brassicae, Apiotrichum montevideense, and Apiotrichum veenhuisii), three Cutaneotrichosporon (Cutaneotrichosporon cavernicola, Cutaneotrichosporon cutaneum, and Cutaneotrichosporon dermatis), Pascua guehoae, and Takashimella koratensis. C. dermatis also underwent pseudo-hyphal growth. Multi-septation increased in seven dimorphic yeasts, including five Trichosporon spp., Trichosporon faecale, and C. dermatis. The vacuolar area was significantly extended in T. asahii, T. aquatile, T. ovoides, and C. dermatis. Lipid droplet size increased only in Trichosporon inkin; however, it decreased in T. asahii, T. coremiiforme, and T. faecale. Additionally, lipid droplet number was preferentially altered in Apiotrichum and Cutaneotrichosporon. These results suggested that magnesium-induced multi-septation and vacuolar area expansion phenotypically distinguish Trichosporon hyphae from Apiotrichum and Cutaneotrichosporon hyphae and distinguish C. dermatis pseudo-hyphae from Cutaneotrichosporon spp. Moreover, differences in lipid droplet size can discriminate species within Trichosporon. Our results suggest that phenotypic alteration via magnesium treatment can contribute to the characterization of Trichosporonales yeasts. These findings provide insights into fungal pathogenesis and may support new treatment strategies.IMPORTANCEMagnesium sulfate considerably affects hyphal growth and cellular organization in Trichosporon asahii. To examine the commonality of this phenotype in Trichosporonales, we treated 30 Trichosporonales yeasts with magnesium sulfate and observed genus-level phenotypic alterations. Using cell length measurement, lipid droplet staining, septum staining, and vacuole staining, considerable hyphal diversity was observed among Trichosporonales. Notably, differences in the multi-septation phenotype and vacuolar size distinguished Trichosporon hyphae from Apiotrichum and Cutaneotrichosporon hyphae and distinguished Cutaneotrichosporon dermatis from other Cutaneotrichosporon spp. Moreover, differences in lipid droplet phenotype divided Trichosporon hyphae into two groups. Our study revealed the relationship between hyphal morphology and phylogenetic systematics in Trichosporonales.

Characterization of Virulence Factors, Cellular Stress Response, and Antifungal Susceptibility Testing of Trichosporon spp. Isolated from Northeast Brazilian Patients

Trichosporon spp. are emerging pathogens that may cause high mortality rates, specifically among immunocompromised individuals. The objectives of this study were to perform a phylogenetic analysis of Trichosporon spp. clinical isolates. We also evaluated the expression of different virulence factors in vitro. In addition, the isolates were grown in the presence of cell-wall and membrane stressors. The antifungal susceptibility profiling was determined. The most prevalent strains belonged to the recently described species T. austroamericanum, with 17 isolates. The other strains were identified as follows: T. asahii (n = 4), T. faecale (n = 2), and T. asteroides (n = 2). All the isolates of T. asahii, T. faecale, and T. asteroides were strong biofilm producers. Statistical analysis revealed that T. asahii strains produced more biofilm than T. austroamericanum. Higher cell surface hydrophobicity was also found for T. asahii isolates compared to T. austroamericanum counterparts. T. austroamericanum seems to be more susceptible to Congo Red, Calcofluor White, and SDS than T. asahii. It is possible to conclude that Trichosporon spp. may present peculiarities in terms of the expression of different virulence factors in vitro, besides displaying a variable susceptibility to different cellular stressors. T. faecale isolates may present high MICs to the azoles, while T. asahii against amphotericin B.

Clinical significance of nosocomial Trichosporon asahii in urine: A retrospective cohort study

OBJECTIVES

To describe the clinical characteristics and outcomes of patients with urine cultures positive for Trichosporon sp with nosocomial acquisition.

METHODS

Retrospective cohort study between 2019 and 2023 that included all patients with urinary isolates of Trichosporon sp; their clinical data and outcomes were drawn from medical records.

RESULTS

Twenty-six patients had urinary Trichosporon asahii. Length of hospital stay before urinary culture with T. asahii averaged 25 days. Seventy percent stayed in the intensive care unit. All patients had an additional bacterial infection and were receiving antibiotic therapy. During the first 30 days, only 57 % were alive. There were no factors significantly associated with mortality.

CONCLUSIONS

The isolation of T. asahii in urine cultures of patients with extended hospital stay does not suggest invasive disease. T. asahii in urine may be a marker of critically ill patients with a high risk of mortality.

Voriconazole successfully treats intracranial Trichosporon asahii infection in an immunocompetent patient: a rare case report and literature review

Trichosporon asahii (T. asahii) has been increasingly recognized as the causative pathogen of invasive fungal infection, whereas intracranial infection caused by T. asahii are extremely scarce. Here, we report a rare case of intracranial T. asahii infection in an immunocompetent woman from China. She was hospitalized for obstructive hydrocephalus and experienced two brain surgeries. One week after the second surgery, the patient developed fever, vomiting, and elevated infection-related indicators. Cerebrospinal fluid (CSF) cultures yielded T. asahii and its morphology was demonstrated by Gram staining. The patient initially received empiric antifungal therapy with voriconazole (VCZ), and the subsequent drug sensitivity results supported the continuation of this therapy. Finally, 15 days of VCZ administration successfully achieved satisfactory therapeutic effects. This case highlights that T. asahii has emerged as an infectious cause of intracranial fungal infection in immunocompetent people. Early recognition and adequate antifungal treatment are paramount to ensure a favorable prognosis.

Fungal Nomenclature: One Fungus, One Name?

Fungal nomenclature has been subject to change for many years and will probably continue to evolve and change in the future. One Fungus One Name principle guided the mycologists to reach a consensus on a single name. The change is inevitable in science; however, it comes with several challenges particularly in routine mycology laboratory practice and patient care, creating further difficulties and resistance to change. To overcome these challenges, the reason for change should be clear and made available on a publicly accessible source. Here, the changes of names in medically important fungi and the rationale behind are summarized.

Candida albicans in the oral cavities of pets: biofilm formation, putative virulence, antifungal resistance profiles and classification of the isolates

The study aimed to investigate Candida albicans presence, antifungal resistance, biofilm formation, putative virulence genes, and molecular characterization in oral samples of dogs and cats. A total of 239 oral samples were collected from cats and dogs of various breeds and ages at Erciyes University, Faculty of Veterinary Medicine Clinics, between May 2017 and April 2018. Among 216 isolates obtained, 15 (6.95%) were identified as C. albicans, while 8 (3.7%) were non-albicans Candida species. Antifungal susceptibility testing revealed sensitivities to caspofungin, fluconazole, and flucytosine in varying proportions. Molecular analysis indicated the presence of fluconazole and caspofungin resistance genes in all C. albicans isolates. Additionally, virulence genes ALS1, HWP1, and HSP90 showed variable presence. Biofilm formation varied among isolates, with 46.7% strong, 33.3% moderate, and 20% weak producers. PCA analysis categorized isolates into two main clusters, with some dog isolates grouped separately. The findings underscore the significance of oral care and protective measures in pets due to C. albicans prevalence, biofilm formation, virulence factors, and antifungal resistance in their oral cavity, thereby aiding clinical diagnosis and treatment in veterinary medicine.

Trichosporon asahii: emerging challenges in pathogenesis and drug resistance

Trichosporon asahii (T. asahii) is an opportunistic pathogenic fungus that often causes severe infections in immunosuppressed patients. Among Trichosporon species, T. asahii is the most pathogenic and lethal species. Current research faces challenges related to unknown pathogenic mechanisms, complex resistance mechanisms, insufficiently rapid and accurate diagnostic methods, and insufficient research on susceptibility to infection. These issues need to be explored in depth. This review summarizes research progress on the origin and classification of T. asahii, its virulence factors and pathogenic mechanisms, epidemiological characteristics, infection modes, diagnostic methods, drug treatment options, and drug resistance mechanisms. Traditional culture combined with molecular biology techniques, such as polymerase chain reaction and gene sequencing, has improved the accuracy and speed of detection. Treatment relies mainly on azole antifungal drugs and amphotericin B; however, patients are facing the problem of drug resistance. New techniques, such as gene knockout and gene sequencing, have identified resistance mechanisms, thus supporting the development of novel antifungal drugs. In summary, an in-depth study of T. asahii will aid in developing more effective diagnostic and therapeutic methods and improve patient prognosis.

Trichosporon asahii: A Potential Growth Promoter for C. gallinacea? Implications for Chlamydial Infections and Cell Culture

The cultivation of Chlamydia gallinacea, a recently identified species, is challenging due to the lack of an optimized protocol. In this study, several infection protocols were tested, including different cell lines, incubation temperatures, centrifugation methods and culture media. However, none were successful in field samples. The only exception was a chance co-culture with Trichosporon asahii, a microorganism commonly found in the chicken gut. This suggests that current in vitro methods may not be optimized for this species and that host-associated microorganisms may influence the in vivo growth of C. gallinacea, which is typically found in the chicken gut. These findings raise new questions and highlight the need for further investigation of microbial interactions within the host, particularly to understand their role in the proliferation of chlamydial species.

First Identification of Emerging Pathogenic Yeast in Clogmia albipunctata (Diptera: Psychodidae) at a Brazilian Hospital

Psychodinae (Diptera: Psychodidae), commonly known as "drain flies", are a subfamily of insects adapted to environments modified by humans. While often regarded as harmless, it has been reported that they may carry pathogenic microorganisms, contributing to hospital environmental contamination and potentially playing a role in healthcare-associated infections. This study aimed to investigate drain flies in a hospital setting to assess their role in carrying microbial pathogens. Twenty-six drain flies were collected from a tertiary hospital using sterile tubes and processed within two hours. The insects were identified as Clogmia albipunctata (Williston, 1893). Whole-body macerates were cultured on EMB media, and fungal isolates were identified using MALDI-TOF MS and ITS region sequencing. The emergent pathogen Trichosporon asahii was isolated, highlighting the potential role of C. albipunctata as a mechanical vector of fungal pathogens associated with HAIs. These findings underscore the importance of monitoring drain flies as part of infection prevention and control strategies in healthcare settings.

Comparative Genomic Analysis of an Apiotrichum cacaoliposimilis Strain Isolated from a Patient with Urinary Tract Infection

Opportunistic infections caused by fungi, particularly those occurring in immunocompromised patients, are considered challenging worldwide. Therefore, a comprehensive understanding of pathogenic fungi is necessary. The present study reports the isolation of a strain of Apiotrichum cacaoliposimilis, which is difficult to detect using conventional clinical assays, from the sterile urine samples of a patient with a urinary tract infection. Sanger sequencing of the internal transcribed spacer regions confirmed the genus of the microbe, while whole-genome sequencing yielded the initial genome assembly of A. cacaoliposimilis. A total of 7,161 predicted proteincoding genes were mapped using multiple databases, including Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, non-redundant protein database, Pathogen-Host Interactions Database, and Comprehensive Antibiotic Resistance Database. The phenotypic data, biochemical reactions, and antimicrobial susceptibility analyses were conducted to reveal the metabolic properties, virulence, and drug resistance profile of the isolated A. cacaoliposimilis. The rank-sum test revealed the differences in the intergeneric distribution of the highly virulent genes UgeB and Pem2. In addition, other genes exhibited significant overlap in terms of virulence factors with the clinical isolate Apiotrichum mycotoxinivorans GMU1709. Fortunately, similar to most fungi belonging to the Apiotrichum genus, the isolate investigated in the present study was also sensitive to the drug voriconazole (MIC = 0.06 μg/ml). In summary, the phylogenetic placement, potential pathogenic genes, drug sensitivity patterns, and morphological characteristics of the isolated A. cacaoliposimilis were determined precisely in the present study.

A unique presentation of subcutaneous Cutaneotrichosporon debeurmannianum infection: A case report of a diagnostic challenge

Introduction

Cutaneotrichosporon debeurmannianum is a yeast-like anamorphic rare fungus commonly found in tropical areas. This case report is the first one located in South America.

Case report

A 67-year-old patient presented with a 5-year history of right foot pain attributed to foot trauma while at sea 5 years prior. During surgical exploration, an impressive whitish cerebriform-like cyst was encountered. Genetic analysis using the genes ITS1, ITS4, LSU-R, and LSU-F was performed, and a phylogenetic tree identified C. debeurmannianum.

Conclusion

A complete characterization of this fungus which causes human disease has not yet been achieved and more research is needed.

Trichosporon infection in chronic kidney disease patients from a tertiary care hospital - a case series or an outbreak? An unanswered question but a well-managed problem

While the majority of Trichosporon spp. isolated in clinical laboratories are typically associated with episodes of colonization or superficial infections, this fungal species has gained recognition as an opportunistic pathogen, leading to invasive infections worldwide. In this article, we present a case series of Trichosporon spp. identified through conventional methods, complemented by MALDI-TOF analysis from a reference institute for a single sample. The reported cases occurred within a confined time frame, and the construction of an epidemic curve suggested a common source with intermittent exposure. Despite the absence of identified breaches in infection prevention and control (IPC) in units with common exposure, this case series underscores the significance of considering Trichosporonosis in the differential diagnoses for post-transplant and chronic kidney disease patients, particularly those undergoing hemodialysis or utilizing Foley's catheter. Notably, research gaps were identified, emphasizing the need for further exploration of factors such as the role of magnesium and prolonged antibiotic usage in the development of invasive Trichosporon infections and newer treatment modalities against biofilm producing yeast like fungi.

Mid-term results of a case series on branched xenopericardial roll graft replacement to treat aortic arch/arch graft infection

OBJECTIVES

We conducted this case series to evaluate the feasibility and mid-term outcomes of orthotopic aortic arch reconstruction using xenopericardial grafts to treat native aortic arch/arch graft infection.

METHODS

Between 2010 and 2023, adopting a multidisciplinary approach, we treated consecutive patients with aortic arch/arch graft infection by orthotopic branched xenopericardial roll graft replacement and tissue filling. The end points of the study were the graft reinfection and graft-related complications such as pseudoaneurysm formation, thromboembolism, graft stenosis, graft calcification and death.

RESULTS

The subjects were 11 patients (8 men and 3 women) with a median age of 66 [51-79, (interquartile range) 59.0, 70.5] years. Of the 11 patients, 7 underwent preoperative mediastinal irrigation/negative-pressure wound treatment. The 30-day mortality was 0% (0/11 patients), and 1 patient died in the hospital after 8 months. Aorta-related death occurred in 18.2% (2/11 patients), with both cases developing local recurrence of fungal infection. The remaining 9 patients (81.8%) remained free of reinfection. The estimated 1-, 3-, 5- and 7-year risk-adjusted survival rates were 91 ± 9%, 81 ± 12%, 58 ± 16% and 58 ± 16%, respectively. The estimated 1-, 3-, 5- and 7-year cumulative aorta-related mortality rates were 9 ± 9%, 19 ± 12%, 19 ± 12% and 19 ± 12%, respectively. Graft-related complications included branch kinking in 1 patient and graft rupture in 1 patient. There were no cases of graft-related thromboembolism or graft calcification. The median follow-up period was 45 [8-101, (interquartile range) 36.5, 70.9] months. The longest follow-up period until date of the currently surviving patients is 101 months.

CONCLUSIONS

Although the xenopericardium appeared to be vulnerable to fungal infection, based on the favourable results obtained, we consider that branched xenopericardial roll graft replacement using a multidisciplinary, staged approach may serve as a useful treatment option for aortic arch/arch graft infection.

Chemical composition, antifungal activity, antibiofilm and citotoxicity of the essential oil of Citrus deliciosa tenore

The leaves of Citrus deliciosa Tenore were collected in southern Brazil, dried, and subjected to the hydrodistillation process to obtain the essential oil. The extraction of essential oil yielded 0.97% ± 0.04. The chromatographic profile of this compound revealed 11 substances, being methyl N-methyl-anthranilate (75.1%), γ-terpinene (13.8%), and Limonene (7%) as major substances. The essential oil shows antifungal action against all tested yeasts, with promising action against Cryptococcus neoformans, Cryptococcus gattii, and Trichosporon asahii. This compound was also able to inhibit the biofilm production of Candida albicans, Candida glabrata, Candida parapsilosis, and T. asahii. The essential oil of tangerine showed weak antioxidant action. It did not show cytotoxicity in human mononuclear cells. It is hoped that these results may guide future studies for the production of formulations that can be used in the treatment of biofilms caused by yeasts, as well as in candidiasis, cryptococcosis, and/or trichosporonosis.

Analysis of fungal diversity in the feces of Arborophila rufipectus

Background

Intestinal fungal composition plays a crucial role in modulating host health, and thus is of great significance in the conservation of endangered bird species. However, research on gut fungal composition in birds is limited. Therefore, in this study, we aimed to examine gut fungal community and potential fecal pathogen composition in wild Arborophila rufipectus.

Methods

Fecal samples were collected from the habitats of wild A. rufipectus and Lophura nycthemera (a widely distributed species belonging to the same family as A. rufipectus) in summer and autumn. Thereafter, RNA was collected and the internal transcribed spacer rRNA gene was sequenced via high-throughput sequencing to investigate seasonal variations in intestinal core fungi, microbial fungi, and potential pathogenic fungi.

Results

The gut microbiota of A. rufipectus and L. nycthemera were highly similar and mainly consisted of three phyla, Ascomycota (58.46%), Basidiomycota (28.80%), and Zygomycota (3.56%), which accounted for 90.82% of the fungal community in all the samples. Further, the predominant genera were Ascomycota_unclassified (12.24%), Fungi_unclassified (8.37%), Davidiella (5.18%), Helotiales_unclassified (2.76%), Wickerhamomyces (1.84%), and Pleosporales_unclassified (1.14%), and the potential fecal pathogens identified included Candida, Cryptococcus, Trichosporon, and Malassezia.

Conclusion

Our results provide evidence that the diversity of intestinal fungi in the endangered species, A. rufipectus, is similar to that in the common species, L. nycthemera, and may serve as a basis for monitoring the status of A. rufipectus and for developing conservation measures.

Emerging Fungal Infections of the Central Nervous System in the Past Decade: A Literature Review

INTRODUCTION

Invasive fungal infections affecting the central nervous system (CNS) are a major health concern worldwide associated with high mortality rates. Their increased incidence is largely due to an increase in the vulnerable immunocompromised population, changing environmental factors, and development of more accurate diagnostic methods. The aim of this article is to identify fungal causes of CNS infections that are recently emerging or have the potential to become emerging pathogens in the near future, as well as their clinical characteristics, including: Candida auris, Trichosporon spp., Blastomyces spp., Sporothrix spp., Talaromyces marneffei, Lomentospora prolificans, and Scedosporium spp.

METHODS

A review of the literature in PubMed in the last ten years was conducted to identify central nervous system infections caused by each of these fungi.

RESULTS

The review identified 10 cases caused by C. auris, 5 cases by Trichosporon spp., 82 cases by Blastomyces spp., 36 cases by Sporothrix spp., 21 cases by T. marneffei, 22 cases by Lomentospora prolificans, and 42 cases by Scedosporium spp.

DISCUSSION

The exact burden of these diseases remains difficult to ascertain, but their apparent rise underscores the urgent need for improved diagnostic, treatment, and management strategies against CNS fungal pathogens to improve outcomes against these life-threatening infections.

Photodynamic therapy combined with voriconazole of extensive ulcer caused by Trichosporon asahii

Trichosporon species are part of the normal microbiota of humans which can cause both superficial and invasive infections, primarily affecting immunocompetent and immunocompromised hosts, respectively. Giant ulcer caused by Trichosporon asahii is relatively uncommon in immunocompetent hosts. Increased drug resistance and biofilm-associated virulence makes the treatment of infectious ulcers challenging. Herein, we present a case of a massive ulcer caused by T. asahii which resulted in completed healing when treated with photodynamic therapy (PDT) and voriconazole. It provided the feasibility for PDT combined with antifungal drugs to treat similar refractory cases.

Isolation of fungi from the Trichosporonaceae family in urine samples from COVID-19 patients: Should we worry about it?

BACKGROUND

Trichosporon genus encompasses emergent fungal pathogens with an increased incidence that concerns potential multi-drug resistance and mortality, especially in immunocompromised patients. COVID-19 is a disease of pandemic proportions with complications related to cytokine storm and lymphopenia.

AIMS

To study the isolation of fungi within the Trichosporanaceae family in patients infected with SARS-CoV-2.

METHODS

In this work we recovered 35 fungal isolates belonging to the Trichosporonaceae family from urine samples of 32 patients hospitalized due to COVID-19 complications. We evaluated their mycological characteristics, as well as the patient's clinical aspects.

RESULTS

Trichosporon asahii was the main species identified, followed by Cutaneotrichosporon jirovecii and Trichosporon inkin, respectively. The blood cultures of 20 of these patients were all negative for fungi. Isolation of Trichosporonaceae fungi in urine was associated with high COVID-19 severity. The antifungal susceptibility test showed low MIC values for voriconazole, an antifungal in the first-line treatment of trichosporonosis. In contrast, high MIC values were found in the case of amphotericin B and 5-fluorocytosine in all the species, except for C. jirovecii. Since invasive trichosporonosis was not confirmed, none of the patients were given an antifungal treatment, without affecting the outcome of the patients.

CONCLUSIONS

Our results suggest that the isolation in urine of fungi from the Trichosporonaceae family may be associated to more severe forms of the disease COVID-19, but not with an increase in death rate. However, these isolates do not seem to be linked to urinary infections, therefore no antifungal therapy is mandatory in these cases.

Identification of Trichosporon yeast isolates from superficial infections in male patients from Central Brazil: an approach to the diversity of infections caused by this basidiomycete fungus

The genus Trichosporon are currently recognized as opportunistic pathogens capable of causing superficial "white piedra" infections and potentially fatal invasive diseases (Trichosporonosis). In this work, determine the agent Trichosporon spp. isolated from the skin and appendages of a male population group in the Central-West region of Brazil. The isolates were analyzed by phenotypic, biochemical and molecular methods. Twenty-five strains of Trichosporon were isolated: T. asahii (18; 72%), followed by T. inkin (4; 16%) and T. faecale (3; 12%). Skin infections were the most affected (16; 64%) and the genitocrural region (13; 52%) was the most affected. The highest rate of isolation occurred between the ages of 21 and 30 years (9; 36%), with black men (African descent) (13; 52%) being the most affected by this type of superficial infection. After the advent of molecular techniques, more than 50 subspecies and about 16 different strains have been reported to cause human disease. In this series, three species of the genus Trichosporon of medical importance were highlighted, colonizing the genital and perigenital region of the studied population. For the identifications, classical phenotypic methods associated with genotypic identification were carried out, using molecular techniques based on the study of DNA; using sequence analysis of the DNA intergenic spacer region 1 (IGS1).

Microbial landscape of cooked meat products: evaluating quality and safety in vacuum-packaged sausages using culture-dependent and culture-independent methods over 1 year in a sustainable food chain

Over the last few decades, advancements in process safety and quality methods have been significantly improved, yet new challenges continue to emerge in the sustainable food supply chain. This study aimed to investigate some physicochemical and microbiological parameters impacting meat products, particularly cooked sausages, within a sustainable supply chain, focusing on quality, spoilage populations, and syneresis formation under vacuum conditions. A comprehensive analysis was conducted on 355 samples collected over four seasons using high-throughput sequencing (16S/ITS) and microbiological and physicochemical [pH and water activity (aw)] assessments. The microbial growth predictor MicroLab_ShelfLife was employed, and multiple factor analysis (MFA) and agglomerative hierarchical clustering (AHC) were utilized to understand how these variables influence the microbiome resilience of these products. Lactic and acetic acids were correlated with the microbiome of the sausages and the liquid coating covering them using metagenomic analyses. The study highlighted that 52% of the evaluated meat industries in southeastern Brazil are implementing effective protocols for sustainable chain production. The results indicated that the durability of vacuum-packaged cooked sausages was primarily influenced by storage temperature (RV coefficient of 0.906), initial microbial load (0.755), and aw (0.624). Average microbial counts were 4.30 log cfu/g (initial), 4.61 (7°C/4 days), 4.90 (7°C/8 days), 6.06 (36°C/4 days), and 6.79 (36°C/8 days). Seasonal durability analysis revealed that winter had the highest average durability of 45.58 days, while summer had the lowest at 26.33 days. Yeast populations, including Trichosporon sp. and Candida sp., were identified as key genera influencing spoilage dynamics. In addition, Bacillus species emerged as dominant spoilage microorganisms, highlighting the need for new critical controls. This study demonstrates the impact of metagenomic approaches, including ITS and 16S amplicon sequencing, in revealing microbial community dynamics, storage temperature, and aw, which are essential for developing targeted interventions to enhance food safety and quality sustainably.

Meningitis Due to Apiotrichum mycotoxinivorans: A Rare Case Report

A young adult male presented as a case of meningitis in the background of a ventriculoperitoneal shunt in situ, uncontrolled type 1 diabetes and a history of treated abdominal tuberculosis. The patient presented with complaints of high-grade fever, non-projectile vomiting, headache and drowsiness. He was eventually diagnosed as a case of fungal meningitis. The patient's cerebrospinal fluid analysis (CSF) analysis revealed budding yeast cells and the culture revealed Apiotrichum mycotoxinivorans. This is a yeast-like fungus that is known to cause opportunistic infections in an immunocompromised host. This is a rare cause of fungal meningitis and very few cases have been reported worldwide. This is the first case of Apiotrichum mycotoxinivorans-associated meningitis reported from India.

What are the 100 most cited fungal genera?

The global diversity of fungi has been estimated between 2 to 11 million species, of which only about 155 000 have been named. Most fungi are invisible to the unaided eye, but they represent a major component of biodiversity on our planet, and play essential ecological roles, supporting life as we know it. Although approximately 20 000 fungal genera are presently recognised, the ecology of most remains undetermined. Despite all this diversity, the mycological community actively researches some fungal genera more commonly than others. This poses an interesting question: why have some fungal genera impacted mycology and related fields more than others? To address this issue, we conducted a bibliometric analysis to identify the top 100 most cited fungal genera. A thorough database search of the Web of Science, Google Scholar, and PubMed was performed to establish which genera are most cited. The most cited 10 genera are Saccharomyces, Candida, Aspergillus, Fusarium, Penicillium, Trichoderma, Botrytis, Pichia, Cryptococcus and Alternaria. Case studies are presented for the 100 most cited genera with general background, notes on their ecology and economic significance and important research advances. This paper provides a historic overview of scientific research of these genera and the prospect for further research. Citation: Bhunjun CS, Chen YJ, Phukhamsakda C, Boekhout T, Groenewald JZ, McKenzie EHC, Francisco EC, Frisvad JC, Groenewald M, Hurdeal VG, Luangsa-ard J, Perrone G, Visagie CM, Bai FY, Błaszkowski J, Braun U, de Souza FA, de Queiroz MB, Dutta AK, Gonkhom D, Goto BT, Guarnaccia V, Hagen F, Houbraken J, Lachance MA, Li JJ, Luo KY, Magurno F, Mongkolsamrit S, Robert V, Roy N, Tibpromma S, Wanasinghe DN, Wang DQ, Wei DP, Zhao CL, Aiphuk W, Ajayi-Oyetunde O, Arantes TD, Araujo JC, Begerow D, Bakhshi M, Barbosa RN, Behrens FH, Bensch K, Bezerra JDP, Bilański P, Bradley CA, Bubner B, Burgess TI, Buyck B, Čadež N, Cai L, Calaça FJS, Campbell LJ, Chaverri P, Chen YY, Chethana KWT, Coetzee B, Costa MM, Chen Q, Custódio FA, Dai YC, Damm U, de Azevedo Santiago ALCM, De Miccolis Angelini RM, Dijksterhuis J, Dissanayake AJ, Doilom M, Dong W, Alvarez-Duarte E, Fischer M, Gajanayake AJ, Gené J, Gomdola D, Gomes AAM, Hausner G, He MQ, Hou L, Iturrieta-González I, Jami F, Jankowiak R, Jayawardena RS, Kandemir H, Kiss L, Kobmoo N, Kowalski T, Landi L, Lin CG, Liu JK, Liu XB, Loizides M, Luangharn T, Maharachchikumbura SSN, Makhathini Mkhwanazi GJ, Manawasinghe IS, Marin-Felix Y, McTaggart AR, Moreau PA, Morozova OV, Mostert L, Osiewacz HD, Pem D, Phookamsak R, Pollastro S, Pordel A, Poyntner C, Phillips AJL, Phonemany M, Promputtha I, Rathnayaka AR, Rodrigues AM, Romanazzi G, Rothmann L, Salgado-Salazar C, Sandoval-Denis M, Saupe SJ, Scholler M, Scott P, Shivas RG, Silar P, Souza-Motta CM, Silva-Filho AGS, Spies CFJ, Stchigel AM, Sterflinger K, Summerbell RC, Svetasheva TY, Takamatsu S, Theelen B, Theodoro RC, Thines M, Thongklang N, Torres R, Turchetti B, van den Brule T, Wang XW, Wartchow F, Welti S, Wijesinghe SN, Wu F, Xu R, Yang ZL, Yilmaz N, Yurkov A, Zhao L, Zhao RL, Zhou N, Hyde KD, Crous PW (2024). What are the 100 most cited fungal genera? Studies in Mycology 108: 1-411. doi: 10.3114/sim.2024.108.01.

Invasive fungal infection caused by Blastobotrys mokoenaii in an immunocompromised patient with acute myeloid leukemia: A case report

Blastobotrys is a genus of rare yeast that is increasingly recognized as a cause of fungal infections in humans. However, there have been no reports of fungal infections in humans caused by Blastobotrys mokoenaii. We describe a case of invasive fungal infection (IFI) caused by B. mokoenaii in an immunocompromised patient with acute myeloid leukemia (AML). A 46-year-old man with relapsed/refractory AML underwent a second allogeneic peripheral blood hematopoietic stem cell transplantation (allo-PBSCT) during remission. The patient had prolonged neutropenia and received systemic steroid therapy for graft-versus-host disease before the second allo-PBSCT. Uncommon yeast was isolated from the blood cultures obtained on day 4. We initially suspected that the uncommon yeast was Trichosporon spp. based on its morphology. However, unlike Trichosporon spp., in vitro antifungal susceptibility tests showed that this yeast isolate was resistant to micafungin, caspofungin, voriconazole, itraconazole, and fluconazole. We performed DNA sequencing and identified it as B. mokoenaii. B. mokoenaii was persistently isolated from blood cultures taken during combination therapy with liposomal amphotericin B and voriconazole. The patient died of multiorgan failure on day 24. B. mokoenaii can cause severe IFI in immunocompromised patients; however, it may not be correctly identified by routine clinical microbiology testing in a hospital laboratory and DNA sequencing is useful for diagnosis.

Adhesion and biofilm formation by two clinical isolates of Trichosporon Cutaneum in various environmental conditions

Trichosporon spp. is an emerging opportunistic pathogen and a common cause of both superficial and invasive infections. Although Trichosporon asahii is the most frequently isolated species, Trichosporon cutaneum is also widely observed, as it is the predominant agent in cases of white Piedra and onychomycosis. Trichosporon spp. is a known to produce biofilms, which serve as one of its virulence mechanisms, however, there is limited data available on biofilms formed by T. cutaneum. Thus, the aim of this study was to assess the adhesion and biofilm formation of two clinical isolates of T. cutaneum under various environmental conditions (including temperature, nutrient availability, and carbon source), as well as their tolerance to fluconazole. Adhesion was tested on common abiotic substrates (such as silicone, glass, and stainless steel), revealing that T. cutaneum readily adhered to all surfaces tested. CV staining was applied for the evaluation of the environment influence on biofilm efficiency and it was proved that the nutrient availability has a major impact. Additionaly, fluorescent staining was employed to visualize the morphology of T. cutaneum biofilm and its survival in the presence of fluconazole. Hyphae production was shown to play a role in elevated biofilm production in minimal medium and increased tolerance to fluconazole.

Unveiling Trichosporon austroamericanum sp. nov.: A Novel Emerging Opportunistic Basidiomycetous Yeast Species

During an epidemiological survey, a potential novel species within the basidiomycetous yeast genus Trichosporon was observed. The clinical strain was obtained from a urine sample taken from a Brazilian kidney transplant recipient. The strain was molecularly identified using the intergenic spacer (IGS1) ribosomal DNA locus and a subsequent phylogenetic analysis showed that multiple strains that were previously reported by other studies shared an identical IGS1-genotype most closely related to that of Trichosporon inkin. However, none of these studies provided an in-depth characterization of the involved strains to describe it as a new taxon. Here, we present the novel clinically relevant yeast for which we propose the name Trichosporon austroamericanum sp. nov. (holotype CBS H-24937). T. austroamericanum can be distinguished from other siblings in the genus Trichosporon using morphological, physiological, and phylogenetic characters.

Trichosporon asahii co-infection with Pneumocystis jiroveci in a renal transplant patient

Trichosporon asahii is considered an opportunistic pathogen, capable of causing superficial infections in humans and invasive deep-seated infections in immunocompromised hosts. Pneumocystis jirovecii can cause life-threatening pneumonia in immunosuppressed patients. Both Trichosporon and Pneumocystis jirovecii are highly lethal in immunocompromised individuals. Here we present a case of invasive Trichosporon asahii co-infection with Pneumocystis jiroveci in a renal transplant patient.

Photodynamic therapy successfully treats refractory onychomycosis caused by Trichosporon asahii: a case report

Onychomycosis, a fungal infection affecting the nail, is characterized by discoloration and thickening of the nail plate and is the most prevalent nail infection globally. We present a case of onychomycosis caused by Trichosporon asahii, a less common etiology. Notably, the patient was successfully treated with a non-traditional antibacterial approach, photodynamic therapy, which has been infrequently documented in the literature for such infections.

Erythematous ulcero-proliferative exophytic lesion in an oral squamous cell carcinoma patient- An unusual case of Trichosporonosis

ABSTRACT

The emergence of non-Candida yeast infections in humans has been increasingly recognized over the last decades. Trichosporon is the third most isolated non-candidal yeast in patients with an impaired immune system. We report a rare case of Trichosporon asahii causing erythematous oral lesion in a patient with squamous cell carcinoma. Our case highlights the occurrence of unusual yeast pathogens in patients with cancer with typical clinical presentations and warrants suspicion of fungal etiology to prevent misdiagnosis of trichosporonosis.

Thielaviopsis paradoxa and cultivable mycobiota associated with carapace of Rhynchophorus palmarum L. (Coleoptera: Curculionidae) in the state of Alagoas, Brazil

Rhynchophorus palmarum (Coleoptera: Curculionidae) is a significant agricultural pest in palm plantations across tropical America, playing a critical role as a vector of the fungus Thielaviopsis paradoxa, which is the causative agent of stem bleeding disease in coconut palms. This disease has raised concerns due to its rapid spread and subsequent reduction in coconut production in northeastern Brazil. Additionally, this insect can establish mutualistic interactions with various fungi, including saprophytic, phytopathogenic, and entomopathogenic fungi, underscoring the importance of identifying its external mycobiota. The aim of this study was to assess the presence of T. paradoxa in the digestive tract and identify the cultivable mycobiota associated with the carapace of R. palmarum. To achieve this, a mycological study was conducted by culturing the external surface and digestive tract of field-caught adult insects (10 males and 10 females) on potato dextrose agar (PDA) in Maceió, Alagoas, Brazil. Fungal identification was performed by correlating microscopic features with the macroscopic characteristics of the obtained colonies. The results showed that T. paradoxa was detected in 15.0% of carapace isolates but was not found in the insects' intestinal tract. Additionally, nine fungal genera frequently associated with saprophytic or phytopathogenic behaviors were identified on the carapace. Eight of these genera belong to the Ascomycota phylum, while one is classified in the Basidiomycota phylum. The ubiquitous presence of Paecilomyces spp. and the occurrence of Trichosporon spp. in 95% of the assessed insects stand out. Furthermore, other potentially phytopathogenic fungi such as Penicillium spp., Fusarium spp., and Aspergillus spp., as well as fungi with entomopathogenic potential like Paecilomyces spp., Trichoderma spp., Metarhizium spp., and Beauveria bassiana, were detected. These findings enhance the understanding of the complex interactions between R. palmarum and its fungal hosts, providing insights for integrated pest management strategies.

Genome-Wide Identification and Characterization of the Medium-Chain Dehydrogenase/Reductase Superfamily of Trichosporon asahii and Its Involvement in the Regulation of Fluconazole Resistance

The medium-chain dehydrogenase/reductase (MDR) superfamily contains many members that are widely present in organisms and play important roles in growth, metabolism, and stress resistance but have not been studied in Trichosporon asahii. In this study, bioinformatics and RNA sequencing methods were used to analyze the MDR superfamily of T. asahii and its regulatory effect on fluconazole resistance. A phylogenetic tree was constructed using Saccharomyces cerevisiae, Candida albicans, Cryptococcus neoformans, and T. asahii, and 73 MDRs were identified, all of which contained NADPH-binding motifs. T. asahii contained 20 MDRs that were unevenly distributed across six chromosomes. T. asahii MDRs (TaMDRs) had similar 3D structures but varied greatly in their genetic evolution at different phylum levels. RNA-seq and gene expression analyses revealed that the fluconazole-resistant T. asahii strain upregulates xylitol dehydrogenase, and downregulated alcohol dehydrogenase and sorbitol dehydrogenase concluded that the fluconazole-resistant T. asahii strain was less selective toward carbon sources and had higher adaptability to the environment. Overall, our study contributes to our understanding of TaMDRs, providing a basis for further analysis of the genes associated with drug resistance in T. asahii.

High-throughput sequencing and characterization of potentially pathogenic fungi from the vaginal mycobiome of giant panda (Ailuropoda melanoleuca) in estrus and non-estrus

Introduction

The giant panda (Ailuropoda melanoleuca) reproduction is of worldwide attention, and the vaginal microbiome is one of the most important factors affecting the reproductive rate of giant pandas. The aim of this study is to investigate the diversity of vaginal mycobiota structure, and potential pathogenic fungi in female giant pandas during estrus and non-estrus.

Methods

This study combined with high-throughput sequencing and laboratory testing to compare the diversity of the vaginal mycobiota in giant pandas during estrus and non-estrus, and to investigate the presence of potentially pathogenic fungi. Potentially pathogenic fungi were studied in mice to explore their pathogenicity.

Results and discussion

The results revealed that during estrus, the vaginal secretions of giant pandas play a crucial role in fungal colonization. Moreover, the diversity of the vaginal mycobiota is reduced and specificity is enhanced. The abundance of Trichosporon and Cutaneotrichosporon in the vaginal mycobiota of giant pandas during estrus was significantly higher than that during non-estrus periods. Apiotrichum and Cutaneotrichosporon were considered the most important genera, and they primarily originate from the environment owing to marking behavior exhibited during the estrous period of giant pandas. Trichosporon is considered a resident mycobiota of the vagina and is an important pathogen that causes infection when immune system is suppressed. Potentially pathogenic fungi were further isolated and identified from the vaginal secretions of giant pandas during estrus, and seven strains of Apiotrichum (A. brassicae), one strain of Cutaneotrichosporon (C. moniliiforme), and nine strains of Trichosporon (two strains of T. asteroides, one strain of T. inkin, one strain of T. insectorum, and five strains of T. japonicum) were identified. Pathogenicity results showed that T. asteroides was the most pathogenic strain, as it is associated with extensive connective tissue replacement and inflammatory cell infiltration in both liver and kidney tissues. The results of this study improve our understanding of the diversity of the vaginal fungi present in giant pandas and will significantly contribute to improving the reproductive health of giant pandas in the future.

Review Article White Piedra: Review of 131 cases

This study analyzes the clinical characteristics of patients diagnosed with White Piedra through a systematic review of cases in the literature. A sample of 131 subjects was considered, of which 91.6% were female and most were 18 years of age or younger. Most studies were conducted in Brazil, followed by India, and Mexico. The most common etiologic agent found was Trichosporon spp (34.3%). Most affected patients were asymptomatic (94.6%) and predisposing factors included long hair, use of a hair band or hair accessories, and wet hair. The most common clinical feature was the presence of nodules. The evaluation of treatment effectiveness was hindered by the scarcity of follow-up information in the majority of the studies. It is concluded that White Piedra infection is more common in young women and is associated with hair-related factors.

Changes in fungal taxonomy: mycological rationale and clinical implications

Numerous fungal species of medical importance have been recently subjected to and will likely continue to undergo nomenclatural changes as a result of the application of molecular approaches to fungal classification together with abandonment of dual nomenclature. Here, we summarize those changes affecting key groups of fungi of medical importance, explaining the mycological (taxonomic) rationale that underpinned the changes and the clinical relevance/importance (where such exists) of the key nomenclatural revisions. Potential mechanisms to mitigate unnecessary taxonomic instability are suggested, together with approaches to raise awareness of important changes to minimize potential clinical confusion.

Soil microbiome indicators can predict crop growth response to large-scale inoculation with arbuscular mycorrhizal fungi

Alternative solutions to mineral fertilizers and pesticides that reduce the environmental impact of agriculture are urgently needed. Arbuscular mycorrhizal fungi (AMF) can enhance plant nutrient uptake and reduce plant stress; yet, large-scale field inoculation trials with AMF are missing, and so far, results remain unpredictable. We conducted on-farm experiments in 54 fields in Switzerland and quantified the effects on maize growth. Growth response to AMF inoculation was highly variable, ranging from -12% to +40%. With few soil parameters and mainly soil microbiome indicators, we could successfully predict 86% of the variation in plant growth response to inoculation. The abundance of pathogenic fungi, rather than nutrient availability, best predicted (33%) AMF inoculation success. Our results indicate that soil microbiome indicators offer a sustainable biotechnological perspective to predict inoculation success at the beginning of the growing season. This predictability increases the profitability of microbiome engineering as a tool for sustainable agricultural management.

A novel report on the emerging and zoonotic neurotropic fungus Trichosporon japonicum in the brain tissue of the endangered Brazilian guitarfish (Pseudobatos horkelii) off the southeastern coast of Brazil

Yeast infections have gained significant attention in the field of marine biology in recent years. Among the broad diversity of marine organisms affected by these infections, elasmobranchs (sharks and rays) have emerged as highly susceptible, due to climate change effects, such as increasing water temperatures and pollution, which can alter the composition and abundance of fungal communities. Additionally, injuries, or compromised immune systems resulting from pollution or disease may increase the likelihood of fungal infections in elasmobranchs. Studies are, however, still lacking for this taxonomic group. In this context, this study aimed to screen yeast species in cell cultures obtained from the brain of artisanally captured Pseudobatos horkelii, a cartilaginous fish that, although endangered, is highly captured and consumed worldwide. Fungi were isolated during an attempt to establish primary cultures of elasmobranch neural cells. Culture flasks were swabbed and investigated using morphological, phenotypic, and molecular techniques. Two isolates of the emerging opportunistic pathogen Trichosporon japonicum were identified, with high scores (1.80 and 1.85, respectively) by the MALDI-ToF technique. This is the first report of the basidiomycetous yeast T. japonicum in Pseudobatos horkelii in Brazil. This finding highlights the need for further research to determine the potential impact on elasmobranch health, ecology, as well as on commercial fisheries.

Differences of clinical characteristics and outcome in proven invasive Trichosporon infections caused by asahii and non-asahii species

BACKGROUND

Trichosporon is an emerging yeast that causes invasive infections in immunocompromised patients experiencing prolonged hospitalisation, indwelling venous catheters and neutropenia.

METHODS

This retrospective observational cohort study analysed invasive Trichosporon infections (ITIs) occurring between January 2005 and December 2022 at three tertiary hospitals and compared the clinical characteristics and prognostic factors of ITIs caused by Trichosporon asahii and non-T. asahii spp. After evaluating 1067 clinical isolates, we identified 46 patients with proven ITIs, defined as cases in which Trichosporon was isolated from blood, cerebrospinal fluid, or sterile tissues.

RESULTS

The patients were separated into T. asahii and non-T. asahii groups containing 25 and 21 patients, respectively, all of which except one were immunocompromised. During this period, both the number of clinical isolates and patients with ITIs (mainly T. asahii) increased; whereas, cases involving non-T. asahii spp. decreased. Compared with the non-T. asahii group, the T. asahii group had more patients with multiple catheters (84% vs. 33%, p = .001) and those receiving renal replacement therapy (48% vs. 14%, p = .005). The all-cause 28-day mortality rate after ITI in the T. asahii group (44%) was significantly higher than in the non-T. asahii group (10%, Log-rank p = .014). The multivariate Cox regression model revealed that T. asahii (reference, non-T. asahii spp.; aHR = 4.3; 95% CI = 1.2-15.2, p = .024) and neutropenia for 5 days or more (aHR = 2.2, 95% CI = 1.5-3.6, p = .035) were independent factors in the 28-day mortality after ITI.

CONCLUSION

The proven ITIs due to T. asahii produced more unfavourable outcomes compared with ITIs caused by non-T. asahii spp.

Genetic analysis of emerging fungal pathogens: Trichosporon asahii

Trichosporon asahii is an emerging opportunistic fungus that mainly causes fatal disseminated trichosporonosis, especially in immunocompromised patients. T. asahii infection has been reported in Thailand, but few studies of this fungus have been published. Therefore, this study investigated the genetic diversity of 51 clinical strains of T. asahii from urine samples in Thailand. We sequenced and characterized the beta-1-tubulin (TUB1), copper-exporting ATPase (ATP), phosphate carrier protein (PHCP), and topoisomerase-1 (TOP1) genes. In addition, intergenic spacer 1 (IGS1) sequences from our previous studies were investigated. The numbers of haplotypes were 3, 3, 2, 2, and 2 for IGS1, TUB1, ATP, PHCP, and TOP1, respectively. The results suggested a relatively low level of genetic diversity among the strains. The findings illustrated that IGS1, TUB1, ATP, PHCP, and TOP1 can be collectively used as an alternative molecular typing tool for investigating the population diversity and structure of T. asahii.

Case report: Diagnostic and therapeutic challenges of fungal endocarditis by Trichosporon asahii in a child with congenital heart defects

Background

patients with congenital cardiopathies are the main group at risk for infective endocarditis (IE) in the pediatric population. Fungal etiology is responsible for 2%-4% of all IEs, and the Trichosporon genus is an increasingly prevalent cause of infections in human beings.

Case presentation

We describe a 9-year-old male with multiple surgical procedures to correct congenital cardiopathy defects, including insertion of RV-PA conduit, who was admitted due to suspicion of pneumonia and needed a surgical approach after being diagnosed with a mycotic pseudoaneurysm in the right ventricle's outflow tract, with dilation of the RV-PA conduit. The conduit was removed and antifungal treatment was started with Voriconazole after the agent was identified (T. asahii), with satisfactory therapeutic response. Approximately 4 years later, the patient was readmitted, presenting with intermittent fever, associated with nocturnal diaphoresis, dry cough, anxiety and chest pain. Vegetations consistent with T. asahii were evidenced in the RV-PA conduit, and a surgical approach was once again necessary.

Discussion

diagnostic methods and treatment of T. asahii endocarditis aren't yet standardized, and recurrent surgical approaches are needed due to the inefficacy of antifungal treatment.

Nasal trichosporonosis in 2 mixed-breed ewes

Two adult mixed-breed ewes were presented with a 2-wk history of upper respiratory disease. Both animals were depressed, with bilateral serosanguineous nasal discharge and harsh bronchovesicular sounds accompanied by crackles and wheezes on auscultation. One animal was recumbent and was euthanized at presentation. The other animal with similar signs, as well as exophthalmos, was euthanized because of a mass in the nasal passages. On autopsy, severe pyogranulomatous and necrotizing ethmoidal rhinitis with focal pyogranulomatous pneumonia was diagnosed in both animals. An intralesional fungal organism was identified in the nares and lungs of both animals. The organism could not be isolated via fungal culture but was identified as Trichosporon sp. by a PCR assay. Trichosporon spp. are rarely associated with disease in veterinary medicine. This ubiquitous fungus might cause disease following trauma to the nasal passages or secondary to immunocompromise.