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Cladophialophora bantiana is an uncommon fungus related to the black yeasts which causes, if untreated, mostly fatal cerebral infections in immunosuppressed and competent patients. We report a case of a patient who survived a recurrent cerebral abscess caused by C. bantiana despite delayed and apparently inappropriate therapy. [ABSTRACT FROM AUTHOR]

The incidence of infections caused by uncommon Chaetomiaceae (Chaetomium and related species) in humans has increased in the recent years. The in vitro activity of eight antifungal drugs (amphotericin B, five azoles, two echinocandins) against 42 morphologically identified Chaetomium strains was determined according to the Clinical and Laboratory Standards Institute (CLSI) guideline. The strains were subsequently identified based on sequences of the internal transcribed spacer 1 and 2 including the intervening 5.8S nrDNA region (ITS) and the partial β tubulin gene (tub2). Chaetomium globosum (n = 24), was the most frequently isolated species, followed by Amesia atrobrunnea (syn. Chaetomium atrobrunnea, n = 6), Dichotomopilus dolichotrichus (syn. Chaetomium dolichotrichum, n = 2) and Acrophialophora jodhpurensis, Chaetomium coarctatum, C. elatum, C. gracile, C. subaffine, C. tarraconense, C. unguicola, Dichotomopilus sp., Dichotomopilus variostiolatus, Ovatospora brasiliensis (all represented by a single strain). The geometric means of the minimum inhibitory concentrations/minimum effective concentrations (MICs/MECs) of the antifungals across all strains were (in increasing order): micafungin 0.12 µg/ml, itraconazole and posaconazole 0.21 µg/ml, amphotericin B 0.25 µg/ml, voriconazole 0.45 µg/ml, isavuconazole 0.54 µg/ml, caspofungin 2.57 µg/ml, and fluconazole 45.25 µg/ml. Micafungin had the lowest geometric mean followed by amphotericin B which had the largest range against tested isolates. All examined C. globosum strains had similar antifungal susceptibility patterns. Fluconazole and caspofungin could not be considered as an option for treatment of infections caused by Chaetomium and chaetomium-like species., Lay Summary: Infections caused by uncommon fungi such as Chaetomium have increased in the recent years. Chaetomium globosum has been reported from onychomycosis and phaeohyphomycosis. This species often induces superficial infections in immunocompetent patients. The taxonomy of Chaetomium spp. has changed dramatically in the last years. Antifungal treatment is a crucial step for managing these kinds of infections. Therefore, the in vitro activity of eight antifungal drugs against Chaetomium strains was determined and β-tubulin (tub2) sequencing was applied to identify the strains. Chaetomium globosum was the most frequent species in our dataset. Based on the results of susceptibility testing, micafungin had the lowest geometric mean followed by amphotericin B. Fluconazole and caspofungin cannot be considered a proper treatment option for infections caused by Chaetomium and chaetomium-like species., (© The Author(s) 2021. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Sporotrichosis is a subcutaneous mycosis caused by traumatic inoculation of pathogenic Sporothrix species. Until recently, Sporothrix globosa was considered as the unique Chinese species causing this disorder. In the present study, 33 clinical Sporothrix strains isolated from Jiangxi, China, were classified and antifungal susceptibility for each strain was determined. Thirteen S. globosa strains and 20 S. schenckii strains were identified by morphology and by multilocus analysis using rDNA ITS, CAL, and EF1α (i.e., internal transcribed spacer, calmodulin and elongation factor-1α). In vitro antifungal susceptibility testing of yeast phases indicated that itraconazole, terbinafine, and posaconazole were most effective against both species, followed by amphotericin B and voriconazole, while fluconazole, 5-fluorocytosine had low efficacy with high MICs. Co-occurrence of S. schenckii and S. globosa in central China may indicate different routes of transmission in this area., (© The Author(s) 2019. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Diutina (Candida) rugosa is emerging as a causative agent of human infections. Recently some close relatives have been described, that is, D. mesorugosa, D. pseudorugosa, and D. neorugosa, some of which have also been implicated in human infection. Phylogenetic relationships of 24 clinical isolates of the D. rugosa complex are reconstructed using multilocus sequence analysis of five housekeeping genes, supplemented with phenotypic studies of CandiSelect™ 4 Agar and nutritional physiology. Diutina mesorugosa could not meaningfully be distinguished from D. rugosa and is regarded as a synonym. Diutina neorugosa and D. pseudorugosa represent separate, distantly related species within the genus Diutina, but have as yet not been encountered in clinical settings.

The importance of fungal infections in both human and animals has increased over the last decades. This article represents an overview of the different categories of fungal infections that can be encountered in animals originating from environmental sources without transmission to humans. In addition, the endemic infections with indirect transmission from the environment, the zoophilic fungal pathogens with near-direct transmission, the zoonotic fungi that can be directly transmitted from animals to humans, mycotoxicoses and antifungal resistance in animals will also be discussed. Opportunistic mycoses are responsible for a wide range of diseases from localized infections to fatal disseminated diseases, such as aspergillosis, mucormycosis, candidiasis, cryptococcosis and infections caused by melanized fungi. The amphibian fungal disease chytridiomycosis and the Bat White-nose syndrome are due to obligatory fungal pathogens. Zoonotic agents are naturally transmitted from vertebrate animals to humans and vice versa. The list of zoonotic fungal agents is limited but some species, like Microsporum canis and Sporothrix brasiliensis from cats, have a strong public health impact. Mycotoxins are defined as the chemicals of fungal origin being toxic for warm-blooded vertebrates. Intoxications by aflatoxins and ochratoxins represent a threat for both human and animal health. Resistance to antifungals can occur in different animal species that receive these drugs, although the true epidemiology of resistance in animals is unknown, and options to treat infections caused by resistant infections are limited.

The description of cryptic species with different pathogenic potentials has changed the perspectives on sporotrichosis. Sporothrix schenckii causes a benign chronic subcutaneous mycosis, Sporothrix brasiliensis is highly virulent, and Sporothrix globosa mainly causes fixed cutaneous lesions. Furthermore, S. brasiliensis is the prevalent species related to cat-transmitted sporotrichosis. Sources of infection, transmission, and distribution patterns also differ between species, and variability differs between species because of different degrees of clonality. The present review article will cover several aspects of the biology of clinically relevant agents of sporotrichosis, including epidemiological aspects of emerging species. Genomic information of Sporothrix spp. is also discussed. The cell wall is an essential structure for cell viability, interaction with the environment, and the host immune cells and contains several macromolecules involved in virulence. Due to its importance, aspects of glycosylation and cell wall polysaccharides are reviewed. Recent genome data and bioinformatics analyses helped to identify specific enzymes of the biosynthetic glycosylation routes, with no homologs in mammalian cells, which can be putative targets for development of antifungal drugs. A diversity of molecular techniques is available for the recognition of the clinically relevant species of Sporothrix. Furthermore, antigens identified as diagnostic markers and putative vaccine candidates are described. Cell-mediated immunity plays a key role in controlling infection, but Sporothrix species differ in their interaction with the host. The adaptive branch of the immune response is essential for appropriate control of infection.

Black yeasts (BY) comprise a group of polyextremotolerant fungi, mainly belonging to the order Chaetothyriales, which are capable of colonizing a wide range of extreme environments. The tolerance to hostile habitats can be explained by their intrinsic ability to survive under acidic, alkaline, and toxic conditions, high temperature, low nutrient availability, and osmotic and mechanical stress. Occasionally, some species can cause human chromoblastomycosis, a chronic subcutaneous infection, as well as disseminated or cerebral phaeohyphomycosis. Three years after the release of the first black yeast genome, the number of projects for sequencing these organisms has significantly increased. Over 37 genomes of important opportunistic and saprobic black yeasts and relatives are now available in different databases. The whole-genome sequencing, as well as the analysis of differentially expressed mRNAs and the determination of protein expression profiles generated an unprecedented amount of data, requiring the development of a curated repository to provide easy accesses to this information. In the present article, we review various aspects of the impact of genomics, transcriptomics, and proteomics on black yeast studies. We discuss recent key findings achieved by the use of these technologies and further directions for medical mycology in this area. An important vehicle is the Working Groups on Black Yeasts and Chromoblastomycosis, under the umbrella of ISHAM, which unite the clinicians and a highly diverse population of fundamental scientists to exchange data for joint publications.

Species of Scedosporium and Lomentospora are considered as emerging opportunists, affecting immunosuppressed and otherwise debilitated patients, although classically they are known from causing trauma-associated infections in healthy individuals. Clinical manifestations range from local infection to pulmonary colonization and severe invasive disease, in which mortality rates may be over 80%. These unacceptably high rates are due to the clinical status of patients, diagnostic difficulties, and to intrinsic antifungal resistance of these fungi. In consequence, several consortia have been founded to increase research efforts on these orphan fungi. The current review presents recent findings and summarizes the most relevant points, including the Scedosporium/Lomentospora taxonomy, environmental distribution, epidemiology, pathology, virulence factors, immunology, diagnostic methods, and therapeutic strategies.

Dermatophyte research has renewed interest because of changing human floras with changing socioeconomic conditions, and because of severe chronic infections in patients with congenital immune disorders. Main taxonomic traits at the generic level have changed considerably, and now fine-tuning at the species level with state-of-the-art technology has become urgent. Research on virulence factors focuses on secreted proteases now has support in genome data. It is speculated that most protease families are used for degrading hard keratin during nitrogen recycling in the environment, while others, such as Sub6 may have emerged as a result of ancestral gene duplication, and are likely to have specific roles during infection. Virulence may differ between mating partners of the same species and concepts of zoo- and anthropophily may require revision in some recently redefined species. Many of these questions benefit from international cooperation and exchange of materials. The aim of the ISHAM Working Group Dermatophytes aims to stimulate and coordinate international networking on these fungi.

Cladophialophora bantiana is a phaeoid fungus that only rarely has been isolated from sources other than the human brain. It has a particular tropism for the central nervous system (CNS). We have integrated and updated large-scale data related to several aspects of C. Bantiana and reviewed all the available reports on its cerebral infections, focusing on their geographical distribution, infection routes, immune status of infected individuals, type and location of infections, clinical manifestations and treatment and outcome, briefly looking over the spectrum of other disease entities associated with C. bantiana, that is, extra-cerebral and animal infections and on the environmental sources of this fungus. Among the agents of phaeohyphomycosis, a term used to describe an infection caused by a dark pigmented fungus, C. bantiana has some significant specific features. A total of 120 case reports were identified with a significantly higher percentage of healthy subjects than immune-debilitated patients (58.3% vs. 41.7%). Infections due to C. bantiana occur worldwide. The main clinical manifestations are brain abscess (97.5%), coinfection of brain tissue and meninges (14.2%) and meningitis alone (2.5%). Among immunocompetent patients, cerebral infection occurred in the absence of pulmonary lesions. The mortality rate is 65.0% regardless of the patient's immune status. The therapeutic options used include surgery or antifungals alone, and the combination of both, in most cases the fatal outcome being rapid after admission. Since the fungus is a true pathogen, laboratory workers should be made aware that BioSafety Level-3 precautions might be necessary., (© The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Human and animal fungal pathogens are a growing threat worldwide leading to emerging infections and creating new risks for established ones. There is a growing need for a rapid and accurate identification of pathogens to enable early diagnosis and targeted antifungal therapy. Morphological and biochemical identification methods are time-consuming and require trained experts. Alternatively, molecular methods, such as DNA barcoding, a powerful and easy tool for rapid monophasic identification, offer a practical approach for species identification and less demanding in terms of taxonomical expertise. However, its wide-spread use is still limited by a lack of quality-controlled reference databases and the evolving recognition and definition of new fungal species/complexes. An international consortium of medical mycology laboratories was formed aiming to establish a quality controlled ITS database under the umbrella of the ISHAM working group on "DNA barcoding of human and animal pathogenic fungi." A new database, containing 2800 ITS sequences representing 421 fungal species, providing the medical community with a freely accessible tool at http://www.isham.org/ and http://its.mycologylab.org/ to rapidly and reliably identify most agents of mycoses, was established. The generated sequences included in the new database were used to evaluate the variation and overall utility of the ITS region for the identification of pathogenic fungi at intra-and interspecies level. The average intraspecies variation ranged from 0 to 2.25%. This highlighted selected pathogenic fungal species, such as the dermatophytes and emerging yeast, for which additional molecular methods/genetic markers are required for their reliable identification from clinical and veterinary specimens., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Sporothrix schenckii sensu lato is a complex of thermally dimorphic species whose natural habitats are soil and plant materials. However, the traumatic implantation of the species into human skin is traditionally thought to be the route leading to the fungal disease sporotrichosis. The complex contains Sporotrhix mexicana, S. globosa, S. brasiliensis, S. luriei, in addition to S. schenckii sensu stricto. In this study we evaluated the differences among these species relative to their frequency in the environment and in human hosts, as well as discuss their remarkable diverse pathogenicity. Today, S. brasiliensis is epidemic in and geographically restricted to Brazil. In contrast, S. mexicana and S. globosa have rarely been reported over the decades. We discovered that the species have been present in collections from clinical cases since 1955 and were able to re-identify six isolates originally classified as S. schenckii as Sporothrix mexicana (three isolates) and Sporothrix globosa (three isolates). Despite their long presence as potential human pathogens they have not shown any increase in frequency as etiologic agents of human infections.

In the framework of a survey on dermatophytoses, 14,619 clinical specimens taken from outpatients with symptoms suggestive of tinea and referred to a Medical Mycology laboratory in Tehran, Iran, were analyzed by direct microscopy and culture. In total, 777 dermatophyte strains recovered in culture were randomly identified by a formerly established RFLP analysis method based on the rDNA ITS regions. For confirmation of species identification, 160 isolates representing the likely entire species spectrum were subjected to ITS-sequencing. Infection was confirmed in 5,175 collected samples (35.4%) by direct microscopy and/or culture. Tinea pedis was the most prevalent type of infection (43.4%), followed by tinea unguium (21.3%), tinea cruris (20.7%), tinea corporis (9.4%), tinea manuum (4.2%), tinea capitis (0.8%) and tinea faciei (0.2%). Trichophyton interdigitale was the most common isolate (40.5%) followed by T. rubrum (34.75%), Epidermophyton floccosum (15.6%), Microsporum canis (3.9%), T. tonsurans (3.5 %) and M. gypseum (0.5%). Other species included M. ferrugineum, T. erinacei, T. violaceum, T. schoenleinii, and a very rare species T. eriotrephon (each one 0.25%). The two strains of T. eriotrephon isolated from tinea manuum and tinea faciei are the second and third reported cases worldwide. Application of DNA-based methods is an important aid in monitoring trends in dermatophytosis in the community.

We report the first case and clinical course of a case of human subcutaneous phaeohyphomycosis caused by Ochroconis tshawytschae, a rare fish pathogen. The diagnosis was based upon histopathological and mycological examinations of clinical samples. Identification of the etiologic agent was assessed on its phenotypic characteristics and subsequently, confirmed by molecular data. In vitro antifungal susceptibility of the isolate was investigated and a comparison was prepared of all of its features to those of its two most relevant related species, O. gallopava and O. humicola.

Black yeasts including Exophiala species are increasingly recognized as agents of human disease. In recent years, progress in molecular phylogeny and taxonomy of the genus Exophiala has led to the description of numerous novel species. The 'classical' but highly variable species Exophiala jeanselmei was split into a number of morphological siblings, which, however, were phylogenetically and clinically remote from each other. E. jeanselmei was restricted to an uncommon species causing subcutaneous infections. Hence only limited information is available on the segregants, among which is E. xenobiotica. We describe a case of an HIV-patient presenting with fungal arthritis and subcutaneous nodules caused by the latter species, which was identified by means of phenotypic and molecular methods.

A novel dermatophyte species is described in the Microsporum cookei clade. It differs significantly from known taxa in the two molecular markers analyzed, i.e., ITS and partial β-tubulin (BT2). Morphologically the species was characterized by smooth- or only slightly rough-walled conidia, but isolates rapidly became pleomorphic with sparse, smooth- and thick-walled macroconidia in addition to microconidia. A teleomorph was found after mating.

A 57-year-old male presented with dermatosis of the dorsum of the foot consisting of tumefaction, deformity and sinus tract formation. The direct examination of exudates as well as the biopsy tissue, demonstrated the presence of black granules. A dematiaceous fungus was isolated from the lesions and was identified by ribosomal DNA sequencing as Cladophialophora bantiana. This is the second report of this fungus as an etiologic agent of eumycetoma in humans. Clinical and mycologic cure was achieved after 20 months of treatment with itraconazole at a starting dose of 300 mg/day that was tapered during the course of therapy. The patient's isolate had an itraconazole MIC of 0.012 microg/ml.