Ecology of Scedosporium Species: Present Knowledge and Future Research

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

A systemic infection involved in lung, brain and spine caused by Scedosporium apiospermum species complex after near-drowning: a case report and literature review

Scedosporium apiospermum species complex are widely distributed fungi that can be found in a variety of polluted environments, including soil, sewage, and decaying vegetation. Those opportunistic pathogens with strong potential of invasion commonly affect immunosuppressed populations However, few cases of scedosporiosis are reported in immunocompetent individuals, who might be misdiagnosed, leading to a high mortality rate. Here, we reported an immunocompetent case of systemtic infection involved in lung, brain and spine, caused by S. apiospermum species complex (S. apiospermum and S. boydii). The patient was an elderly male with persistent fever and systemtic infection after near-drowning. In the two tertiary hospitals he visited, definite diagnosis was extremely difficult. After being admitted to our hospital, he was misdiagnosed as tuberculosis infection, before diagnosis of S. apiospermum species complex infection by the metagenomic next-generation sequencing. His symptoms were alleviated after voriconazole treatment. In the present case, the details associated with its course were reported and published studies on Scedosporium spp. infection were also reviewed, for a better understanding of this disease and reducing the misdiagnosis rate.

Asynchronous application of modified biochar and exogenous fungus Scedosporium sp. ZYY for enhanced degradation of oil-contaminated intertidal mudflat sediment

Intertidal mudflats are susceptible to oil pollution due to their proximity to discharges from industries, accidental spills from marine shipping activities, oil drilling, pipeline seepages, and river outflows. The experimental study was divided into two periods. In the first period, microcosm trials were carried out to examine the effect of chemically modified biochar on biological hydrocarbon removal from sediments. The modified biochar's surface area increased from 2.544 to 25.378 m2/g, followed by a corresponding increase in the hydrogen-carbon and oxygen-carbon ratio, indicating improved stability and polarity. In the second period, the effect of exogenous fungus - Scedoporium sp. ZYY on the bacterial community structure was examined in relation to total petroleum hydrocarbon (TPH) removal. The maximum TPH removal efficiency of 82.4% was achieved in treatments with the modified biochar, followed by a corresponding increase in Fluorescein diacetate hydrolysis activity. Furthermore, high-throughput 16S RNA gene sequencing employed to identify changes in the bacterial community of the original sediment and treatments before and after fungal inoculation revealed Proteobacteria as the dominant phylum. In addition, it was observed that Scedoporium sp. ZYY promoted the proliferation of specific TPH-degraders, particularly, Hyphomonas adhaerens which accounted for 77% of the total degrading populations in treatments where TPH removal was highest. Findings in this study provide valuable insights into the effect of modified biochar and the fundamental role of exogenous fungus towards the effective degradation of oil-contaminated intertidal mudflat sediments.

Fungal Colonization of the Airways of Patients with Cystic Fibrosis: the Role of the Environmental Reservoirs

Filamentous fungi frequently colonize the airways of patients with cystic fibrosis and may cause severe diseases, such as the allergic bronchopulmonary aspergillosis. The most common filamentous fungi capable to chronically colonize the respiratory tract of the patients are Aspergillus fumigatus and Scedosporium species. Defining the treatment strategy may be challenging, the number of available drugs being limited and some of the causative agents being multiresistant microorganisms. The knowledge of the fungal niches in the outdoor and indoor environment is needed for understanding the origin of the contamination of the patients. In light of the abundance of some of the causative molds in compost, agricultural and flower fields, occupational activities related to such environments should be discouraged for patients with cystic fibrosis (CF). In addition, the microbiological monitoring of their indoor environment, including analysis of air and dust on surfaces, is essential to propose preventive measures aiming to reduce the exposure to environmental molds. Nevertheless, some specific niches were also identified in the indoor environment, in relation with humidity which favors the growth of thermotolerant molds. Potted plants were reported as indoor reservoirs for Scedosporium species. Likewise, Exophiala dermatitidis may be spread in the kitchen via dishwashers. However, genotype studies are still required to establish the link between dishwashers and colonization of the airways of CF patients by this black yeast. Moreover, as nothing is known regarding the other filamentous fungi associated with CF, further studies should be conducted to identify other potential specific niches in the habitat.

Detection of Scedosporium spp.: Colonizer or pathogen? A retrospective analysis of clinical significance and management in a large tertiary center

Infections with Scedosporium spp. are emerging in the past two decades and are associated with a high mortality rate. Microbiological detection can be associated with either colonization or infection. Evolution from colonization into infection is difficult to predict and clinical management upon microbiological detection is complex. Microbiological samples from 2015 to 2021 were retrospectively analyzed in a single tertiary care center. Classification into colonization or infection was performed upon first microbiological detection. Clinical evolution was observed until July 2023. Further diagnostic procedures after initial detection were analyzed. Among 38 patients with microbiological detection of Scedosporium spp., 10 were diagnosed with an infection at the initial detection and two progressed from colonization to infection during the observation time. The main sites of infection were lung (5/12; 41.6%) followed by ocular sites (4/12; 33.3%). Imaging, bronchoscopy or biopsies upon detection were performed in a minority of patients. Overall mortality rate was similar in both groups initially classified as colonization or infection [30.7% and 33.3%, respectively (P = 1.0)]. In all patients where surgical debridement of site of infection was performed (5/12; 42%); no death was observed. Although death occurred more often in the group without eradication (3/4; 75%) compared with the group with successful eradication (1/8; 12.5%), statistical significance could not be reached (P = 0.053). As therapeutic management directly impacts patients' outcome, a multidisciplinary approach upon microbiological detection of Scedosporium spp. should be encouraged. Data from larger cohorts are warranted in order to analyze contributing factors favoring the evolution from colonization into infection.

Functional insights into human macrophage response against Scedosporium apiospermum and Scedosporium dehoogii

Fungal infections caused by Scedosporium species are rising among immunocompromised and immunocompetent patients. Within the immunocompetent group, patients with cystic fibrosis (pwCF) are at high risk of developing a chronic airway colonization by these molds. While S. apiospermum is one of the major species encountered in the lungs of pwCF, S. dehoogii has rarely been reported. The innate immune response is believed to be critical for host defense against fungal infections. However, its role has only recently been elucidated and the immune mechanisms against Scedosporium species are currently unknown. In this context, we undertook a comparative investigation of macrophage-mediated immune responses toward S. apiospermum and S. dehoogii conidia. Our data showed that S. apiospermum and S. dehoogii conidia strongly stimulated the expression of a set of pro-inflammatory cytokines and chemokines such as IL-1β, IL-8, IL-6 and TNFα. We demonstrated that S. dehoogii was more potent in stimulating the early release of pro-inflammatory cytokines and chemokines while S. apiospermum induced a late inflammatory response at a higher level. Flow cytometry analysis showed that M1-like macrophages were able to internalize both S. apiospermum and S. dehoogii conidia, with a similar intracellular killing rate for both species. In conclusion, these results suggest that M1-like macrophages can rapidly initiate a strong immune response against both S. apiospermum and S. dehoogii. This response is characterized by a similar killing of internalized conidia, but a different time course of cytokine production.

Clinical manifestations and susceptibility of Scedosporium/Lomentospora infections at a tertiary medical centre in Taiwan from 2014 to 2021: A retrospective cohort study

BACKGROUND

Scedosporiosis/lomentosporiosis is a globally emerging and crucial fungal infection. However, clinical data on Scedosporium/Lomentospora infections in Taiwan are scarce.

OBJECTIVES

This study aimed to explore the clinical characteristics of Scedosporium/Lomentospora-infected patients and evaluate the susceptibility of these isolates to antifungal agents.

METHODS

The clinical features of Scedosporium/Lomentospora-infected patients at a tertiary teaching hospital in Northern Taiwan between 2014 and 2021 were retrospectively reviewed; isolates from these patients were identified to species level for antifungal susceptibility testing.

RESULTS

Among 44 patients, 27 (61.4%) had scedosporiosis/lomentosporiosis, whereas 17 (38.6%) were colonised with Scedosporium/Lomentospora species. Scedosporium apiospermum was the main coloniser; scedosporiosis was primarily caused by S. boydii. Trauma history, steroid and immunosuppressant use were the most common risk factors for developing these infections. Among 27 patients with scedosporiosis/lomentosporiosis, one was lost to follow-up and seven (7/26, 26.9%) died. Most patients with S. apiospermum infection have a history of trauma, leading to cutaneous, bone and ocular infections. Pulmonary, sinus and disseminated infections and mortality were frequently reported in patients with S. boydii infection. Voriconazole's minimum inhibitory concentration was low for S. boydii, S. apiospermum and S. aurantiacum. Caspofungin, micafungin and anidulafungin were active against S. boydii and S. apiospermum. A potentially novel Scedosporium species was identified in this study, with distinct clinical manifestations and antifungal susceptibility.

CONCLUSIONS

At our centre, S. boydii is the main causative species of scedosporiosis; voriconazole could be the first-line treatment in Taiwan. Our study supports the importance of speciation, rather than only categorising these isolates into S. apiospermum species complex.

Comparative pathogenicity of Scedosporium species in murine model of systemic scedosporiosis

Systemic scedosporiosis is a devastating emerging fungal infection caused by several species of the genus Scedosporium in immunocompetent and immunocompromised individuals. In this study, we compared the virulence of different Scedosporium species in a murine model of systemic scedosporiosis by survival assays, fungal burden and histopathological analysis. We found that mice mortality was species-dependent, S. apiospermum, S. aurantiacum and S. dehoogii were the most virulent species. We also observed the dissemination and invasion of Scedosporium species to the brain, spleen and kidney by colony count and histopathological analysis at different times of infection. Particularly, the brain was the tissue most susceptible to invasion during systemic scedosporiosis. This study shows the virulence and pathophysiology of different Scedosporium species and will be useful in facilitating control and prevention strategies for systemic scedosporiosis.

Systemic Lupus Erythematosus With Multi-System Involvement and Immunosuppression Presenting With a Rare Fungal Brain Abscess

The fungal pathogen Scedosporium apiospermum is a ubiquitous opportunistic pathogen found in soil and water that can cause severe infection in hosts with impaired immunity. Patients with systemic autoimmune diseases such as systemic lupus erythematosus (SLE) are already at risk for infections given their altered immunity. This can be exacerbated further in patients taking immune-suppressing medications to control their disease status. Here, we present a case of a rare and challenging clinical scenario of a woman with refractory multi-organ SLE on steroids who developed neurologic deficits found to have a brain abscess caused by a unique fungal etiology.

Exogenous and Endophytic Fungal Communities of Dendrobium nobile Lindl. across Different Habitats and Their Enhancement of Host Plants' Dendrobine Content and Biomass Accumulation

Both the biosynthesis and array of bioactive and medicinal compounds in plants can be influenced by interactions with endophytic and exogenous fungi. However, the composition of endophytic and exogenous fungal communities associated with many medicinal plants is unknown, and the mechanism by which these fungi stimulate the secondary metabolism of host plants is unclear. In this study, we conducted a correlative analysis between endophytic and exogenous fungi and dendrobine and biomass accumulation in Dendrobium nobile across five Chinese habitats: wild Danxia rock, greenhouse-associated large Danxia stone, broken Danxia stone, broken coarse sandstone, and wood spile. Across habitats, fungal communities exhibited significant differences. The abundances of Phyllosticta, Trichoderma, and Hydropus were higher in wild habitats than in greenhouse habitats. Wild habitats were host to a higher diversity and richness of exogenous fungi than were greenhouse habitats. However, there was no significant difference in endophytic fungal diversity between habitats. The differences between the fungal communities' effects on the dendrobine content and biomass of D. nobile were attributable to the composition of endophytic and exogenous fungi. Exogenous fungi had a greater impact than endophytic fungi on the accumulation of fresh weight (FW) and dendrobine in D. nobile. Furthermore, D. nobile samples with higher exogenous fungal richness and diversity exhibited higher dendrobine content and FW. Phyllosticta was the only genus to be significantly positively correlated with both FW and dendrobine content. A total of 86 strains of endophytic fungi were isolated from the roots, stems, and leaves of D. nobile, of which 8 strains were found to be symbiotic with D. nobile tissue-cultured seedlings. The strain DN14 (Phyllosticta fallopiae) was found to promote not only biomass accumulation (11.44%) but also dendrobine content (33.80%) in D. nobile tissue-cultured seedlings. The results of this study will aid in the development of strategies to increase the production of dendrobine in D. nobile. This work could also facilitate the screening of beneficial endophytic and exogenous fungal probiotics for use as biofertilizers in D. nobile.

The high diversity of Scedosporium and Lomentospora species and their prevalence in human-disturbed areas in Taiwan

Scedosporium and Lomentospora are important opportunistic pathogens causing localized or disseminated infection in humans. Understanding their environmental distribution is critical for public hygiene and clinical management. We carried out the first environmental survey in urbanized and natural regions in Taiwan. Overall, Scedosporium and Lomentospora species were recovered in 132 out of 273 soil samples (48.4%) across Taiwan. We morphologically and molecularly identified six Scedosporium and one Lomentospora species. All four major clinical relevant species were isolated with high frequency, i.e., Scedosporium apiospermum (42.4%), S. boydii (21.8%), Lomentosporaprolificans (14.5%), S. aurantiacum (8.5%); two clinically minor species, Pseudallescheria angusta (6.7%) and S. dehoogii (5.6%), and a saprobic species, S. haikouense (0.6%), had moderate to rare incidence. These fungal species had high incidence in urban (48.6%) and hospital (67.4%) soil samples, and had limited distribution in samples from natural regions (5%). Multivariate analysis of the fungal composition revealed strong evidence of the preferential distribution of these fungi in urban and hospital regions compared with natural sites. In addition, strong evidence suggested that the distribution and abundance of these fungal species were highly heterogeneous in the environment; samples in vicinity often yielded varied fungal communities. We concluded that these fungal species were prevalent in soil in Taiwan and their occurrences were associated with human activities. Although, hygiene sensitive sites such as hospitals were not harboring heavier fungal burdens than other urban facilities in our survey, still, aware should be taken for the high frequency of these clinical relevant species around hospital regions.

Non-Aspergillus Hyaline Molds: A Host-Based Perspective of Emerging Pathogenic Fungi Causing Sinopulmonary Diseases

The incidence of invasive sino-pulmonary diseases due to non-Aspergillus hyaline molds is increasing due to an enlarging and evolving population of immunosuppressed hosts as well as improvements in the capabilities of molecular-based diagnostics. Herein, we review the following opportunistic pathogens known to cause sinopulmonary disease, the most common manifestation of hyalohyphomycosis: Fusarium spp., Scedosporium spp., Lomentospora prolificans, Scopulariopsis spp., Trichoderma spp., Acremonium spp., Paecilomyces variotii, Purpureocillium lilacinum, Rasamsonia argillacea species complex, Arthrographis kalrae, and Penicillium species. To facilitate an understanding of the epidemiology and clinical features of sino-pulmonary hyalohyphomycoses in the context of host immune impairment, we utilized a host-based approach encompassing the following underlying conditions: neutropenia, hematologic malignancy, hematopoietic and solid organ transplantation, chronic granulomatous disease, acquired immunodeficiency syndrome, cystic fibrosis, and healthy individuals who sustain burns, trauma, or iatrogenic exposures. We further summarize the pre-clinical and clinical data informing antifungal management for each pathogen and consider the role of adjunctive surgery and/or immunomodulatory treatments to optimize patient outcome.

Extracellularly Released Molecules by the Multidrug-Resistant Fungal Pathogens Belonging to the Scedosporium Genus: An Overview Focused on Their Ecological Significance and Pathogenic Relevance

The multidrug-resistant species belonging to the Scedosporium genus are well recognized as saprophytic filamentous fungi found mainly in human impacted areas and that emerged as human pathogens in both immunocompetent and immunocompromised individuals. It is well recognized that some fungi are ubiquitous organisms that produce an enormous amount of extracellular molecules, including enzymes and secondary metabolites, as part of their basic physiology in order to satisfy their several biological processes. In this context, the molecules secreted by Scedosporium species are key weapons for successful colonization, nutrition and maintenance in both host and environmental sites. These biologically active released molecules have central relevance on fungal survival when colonizing ecological places contaminated with hydrocarbons, as well as during human infection, particularly contributing to the invasion/evasion of host cells and tissues, besides escaping from the cellular and humoral host immune responses. Based on these relevant premises, the present review compiled the published data reporting the main secreted molecules by Scedosporium species, which operate important physiopathological events associated with pathogenesis, diagnosis, antimicrobial activity and bioremediation of polluted environments.

Brain abscess caused by Scedosporium boydii in a systemic lupus erythematosus patient: A case report and literature review

Scedosporium boydii is considered as emerging opportunists affecting both immunocompromised and immunocompetent individuals. Diagnosis and treatment of Scedosporium infections can be challenging, and the outcome is frequently fatal, especially in patients with disseminated infections. Metagenomic next-generation sequencing (mNGS) is a promising adjunctive diagnostic approach for uncommon pathogens. Here, we report a rare case of brain abscess caused by S. boydii in a systemic lupus erythematosus (SLE) patient. This case highlights the importance of mNGS in the early diagnosis of S. boydii. Additionally, the combined application of culture and molecular tools may be promising in the clinical diagnosis of fungal disease.

Lomentospora prolificans: An Emerging Opportunistic Fungal Pathogen

Lomentospora prolificans is an emerging opportunistic pathogen that primarily affects immunocompromised individuals leading to disseminated disease with high mortality rates while also causing infections in healthy populations. Successful recovery from infection is difficult due to high rates of intrinsic resistance to antifungals. Rapid and readily available diagnostic methods, aggressive surgical debridement wherever appropriate, and effective and timely antifungal treatment are the pillars for successful management. Future research will need to clarify the environmental niche of the fungus, further investigate the pathophysiology of infection and define species-specific therapeutic targets.

Novel α-Aminophosphonates and α-Aminophosphonic Acids: Synthesis, Molecular Docking and Evaluation of Antifungal Activity against Scedosporium Species

The Scedosporium genus is an emerging pathogen with worldwide prevalence and high mortality rates that gives multidrug resistance to antifungals; therefore, pharmacological alternatives must be sought for the treatment of diseases caused by this fungus. In the present project, six new α-aminophosphates were synthesized by the Kabachnik–Fields multicomponent reaction by vortex agitation, and six new monohydrolyzed α-aminophosphonic acids were synthesized by an alkaline hydrolysis reaction. Antifungal activity was evaluated using the agar diffusion method as an initial screening to determine the most active compound compared to voriconazole; then it was evaluated against 23 strains of the genus Scedosporium following the M38-A2 protocol from CLSI (activity range: 648.76–700 µg/mL). Results showed that compound 5f exhibited the highest antifungal activity according to the agar diffusion method (≤1 mg/mL). Cytotoxicity against healthy COS-7 cells was also evaluated by the MTT assay and it was shown that compound 5f exhibits a lower toxicity in comparison to voriconazole at the same concentration (1000 µM). A docking study was conducted afterwards, showing that the possible mechanism of action of the compound is through the inhibition of allosteric 14-α-demethylase. Taking these results as a basis, 5f is presented as a compound with attractive properties for further studies.

In depth search of the Sequence Read Archive database reveals global distribution of the emerging pathogenic fungus Scedosporium aurantiacum

Scedosporium species are emerging opportunistic fungal pathogens causing various infections mainly in immunocompromised patients, but also in immunocompetent individuals, following traumatic injuries. Clinical manifestations range from local infections, such as subcutaneous mycetoma or bone and joint infections, to pulmonary colonization and severe disseminated diseases. They are commonly found in soil and other environmental sources. To date S. aurantiacum has been reported only from a handful of countries. To identify the worldwide distribution of this species we screened publicly available sequencing data from fungal metabarcoding studies in the Sequence Read Archive (SRA) of The National Centre for Biotechnology Information (NCBI) by multiple BLAST searches. S. aurantiacum was found in 26 countries and two islands, throughout every climatic region. This distribution is like that of other Scedosporium species. Several new environmental sources of S. aurantiacum including human and bovine milk, chicken and canine gut, freshwater, and feces of the giant white-tailed rat (Uromys caudimaculatus) were identified. This study demonstrated that raw sequence data stored in the SRA database can be repurposed using a big data analysis approach to answer biological questions of interest.

Multilocus Sequence Typing Reveals Extensive Genetic Diversity of the Emerging Fungal Pathogen Scedosporium aurantiacum

Scedosporium spp. are the second most prevalent filamentous fungi after Aspergillus spp. recovered from cystic fibrosis (CF) patients in various regions of the world. Although invasive infection is uncommon prior to lung transplantation, fungal colonization may be a risk factor for invasive disease with attendant high mortality post-transplantation. Abundant in the environment, Scedosporium aurantiacum has emerged as an important fungal pathogen in a range of clinical settings. To investigate the population genetic structure of S. aurantiacum, a MultiLocus Sequence Typing (MLST) scheme was developed, screening 24 genetic loci for polymorphisms on a tester strain set. The six most polymorphic loci were selected to form the S. aurantiacum MLST scheme: actin (ACT), calmodulin (CAL), elongation factor-1α (EF1α), RNA polymerase subunit II (RPB2), manganese superoxide dismutase (SOD2), and β-tubulin (TUB). Among 188 global clinical, veterinary, and environmental strains, 5 to 18 variable sites per locus were revealed, resulting in 8 to 23 alleles per locus. MLST analysis observed a markedly high genetic diversity, reflected by 159 unique sequence types. Network analysis revealed a separation between Australian and non-Australian strains. Phylogenetic analysis showed two major clusters, indicating correlation with geographic origin. Linkage disequilibrium analysis revealed evidence of recombination. There was no clustering according to the source of the strains: clinical, veterinary, or environmental. The high diversity, especially amongst the Australian strains, suggests that S. aurantiacum may have originated within the Australian continent and was subsequently dispersed to other regions, as shown by the close phylogenetic relationships between some of the Australian sequence types and those found in other parts of the world. The MLST data are accessible at http://mlst.mycologylab.org. This is a joined publication of the ISHAM/ECMM working groups on “Scedosporium/Pseudallescheria Infections” and “Fungal Respiratory Infections in Cystic Fibrosis”.

Fungal diversity notes 1512-1610: taxonomic and phylogenetic contributions on genera and species of fungal taxa

This article is the 14th in the Fungal Diversity Notes series, wherein we report 98 taxa distributed in two phyla, seven classes, 26 orders and 50 families which are described and illustrated. Taxa in this study were collected from Australia, Brazil, Burkina Faso, Chile, China, Cyprus, Egypt, France, French Guiana, India, Indonesia, Italy, Laos, Mexico, Russia, Sri Lanka, Thailand, and Vietnam. There are 59 new taxa, 39 new hosts and new geographical distributions with one new combination. The 59 new species comprise Angustimassarina kunmingense, Asterina lopi, Asterina brigadeirensis, Bartalinia bidenticola, Bartalinia caryotae, Buellia pruinocalcarea, Coltricia insularis, Colletotrichum flexuosum, Colletotrichum thasutense, Coniochaeta caraganae, Coniothyrium yuccicola, Dematipyriforma aquatic, Dematipyriforma globispora, Dematipyriforma nilotica, Distoseptispora bambusicola, Fulvifomes jawadhuvensis, Fulvifomes malaiyanurensis, Fulvifomes thiruvannamalaiensis, Fusarium purpurea, Gerronema atrovirens, Gerronema flavum, Gerronema keralense, Gerronema kuruvense, Grammothele taiwanensis, Hongkongmyces changchunensis, Hypoxylon inaequale, Kirschsteiniothelia acutisporum, Kirschsteiniothelia crustaceum, Kirschsteiniothelia extensum, Kirschsteiniothelia septemseptatum, Kirschsteiniothelia spatiosum, Lecanora immersocalcarea, Lepiota subthailandica, Lindgomyces guizhouensis, Marthe asmius pallidoaurantiacus, Marasmius tangerinus, Neovaginatispora mangiferae, Pararamichloridium aquisubtropicum, Pestalotiopsis piraubensis, Phacidium chinaum, Phaeoisaria goiasensis, Phaeoseptum thailandicum, Pleurothecium aquisubtropicum, Pseudocercospora vernoniae, Pyrenophora verruculosa, Rhachomyces cruralis, Rhachomyces hyperommae, Rhachomyces magrinii, Rhachomyces platyprosophi, Rhizomarasmius cunninghamietorum, Skeletocutis cangshanensis, Skeletocutis subchrysella, Sporisorium anadelphiae-leptocomae, Tetraploa dashaoensis, Tomentella exiguelata, Tomentella fuscoaraneosa, Tricholomopsis lechatii, Vaginatispora flavispora and Wetmoreana blastidiocalcarea. The new combination is Torula sundara. The 39 new records on hosts and geographical distribution comprise Apiospora guiyangensis, Aplosporella artocarpi, Ascochyta medicaginicola, Astrocystis bambusicola, Athelia rolfsii, Bambusicola bambusae, Bipolaris luttrellii, Botryosphaeria dothidea, Chlorophyllum squamulosum, Colletotrichum aeschynomenes, Colletotrichum pandanicola, Coprinopsis cinerea, Corylicola italica, Curvularia alcornii, Curvularia senegalensis, Diaporthe foeniculina, Diaporthe longicolla, Diaporthe phaseolorum, Diatrypella quercina, Fusarium brachygibbosum, Helicoma aquaticum, Lepiota metulispora, Lepiota pongduadensis, Lepiota subvenenata, Melanconiella meridionalis, Monotosporella erecta, Nodulosphaeria digitalis, Palmiascoma gregariascomum, Periconia byssoides, Periconia cortaderiae, Pleopunctum ellipsoideum, Psilocybe keralensis, Scedosporium apiospermum, Scedosporium dehoogii, Scedosporium marina, Spegazzinia deightonii, Torula fici, Wiesneriomyces laurinus and Xylaria venosula. All these taxa are supported by morphological and multigene phylogenetic analyses. This article allows the researchers to publish fungal collections which are important for future studies. An updated, accurate and timely report of fungus-host and fungus-geography is important. We also provide an updated list of fungal taxa published in the previous fungal diversity notes. In this list, erroneous taxa and synonyms are marked and corrected accordingly.

Scedosporium and Lomentospora Infections Are Infrequent, Difficult to Diagnose by Histology, and Highly Virulent

OBJECTIVE

To further characterize the histomorphology and clinicopathologic features of colonization and invasive disease by Scedosporium and Lomentospora.

METHODS

We conducted a 20-year retrospective study. Patients with at least 1 histopathology specimen and concurrent culture were included. Clinical features, histopathology, microbiology, and outcomes were analyzed.

RESULTS

Eighteen patients were identified, and all were immunocompromised. Eight patients had colonization, while 10 had invasive disease (pneumonia [n = 3], skin and soft-tissue infections [n = 3], disseminated disease [n = 4]). Scedosporium apiospermum was identified in 15 patients, Lomentospora prolificans in 2 patients, and Scedosporium ellipsoideum in 1 patient. Fungal elements were identified histologically in 11 patients. Granulomatous, suppurative, and necrotizing inflammation with irregular branching hyphae and characteristic microconidia were observed in 9 cases; conidiogenous cells were identified in 4 cases. Seven patients died of invasive disease despite therapy, and 3 recovered after treatment. No deaths were observed in patients with colonization.

CONCLUSIONS

Scedosporium and Lomentospora are rare, virulent opportunistic fungal pathogens. Fungal morphology may overlap with other hyaline molds, but identification of obovoid conidia should allow a diagnosis of non-Aspergillus hyalohyphomycosis and consideration of Scedosporium and Lomentospora. Histopathologic correlation with culture and polymerase chain reaction is critical for diagnosis and treatment.

Fungal Genomics in Respiratory Medicine: What, How and When?

Respiratory infections caused by fungal pathogens present a growing global health concern and are a major cause of death in immunocompromised patients. Worryingly, coronavirus disease-19 (COVID-19) resulting in acute respiratory distress syndrome has been shown to predispose some patients to airborne fungal co-infections. These include secondary pulmonary aspergillosis and mucormycosis. Aspergillosis is most commonly caused by the fungal pathogen Aspergillus fumigatus and primarily treated using the triazole drug group, however in recent years, this fungus has been rapidly gaining resistance against these antifungals. This is of serious clinical concern as multi-azole resistant forms of aspergillosis have a higher risk of mortality when compared against azole-susceptible infections. With the increasing numbers of COVID-19 and other classes of immunocompromised patients, early diagnosis of fungal infections is critical to ensuring patient survival. However, time-limited diagnosis is difficult to achieve with current culture-based methods. Advances within fungal genomics have enabled molecular diagnostic methods to become a fast, reproducible, and cost-effective alternative for diagnosis of respiratory fungal pathogens and detection of antifungal resistance. Here, we describe what techniques are currently available within molecular diagnostics, how they work and when they have been used.

Draft Genome Sequence of the Environmental Fungus Scedosporium dehoogii

Today, the genus Scedosporium comprises at least ten species with four of them, Scedosporium apiospermum, Scedosporium boydii, Scedosporium aurantiacum and Scedosporium minutisporum capable of colonizing the lungs of patients with cystic fibrosis. Scedosporium dehoogii, which is also common in the soil, has never been reported as causing human pulmonary infections. Here we report the first genome sequence for S. dehoogii, an invaluable resource to understand the genetic bases of pathogenesis in the genus Scedosporium.

The Glycosylphosphatidylinositol-Anchored Superoxide Dismutase of Scedosporium apiospermum Protects the Conidia from Oxidative Stress

Scedosporium species are common fungal pathogens in patients with cystic fibrosis (CF). To colonize the CF lungs, fungi must cope with the host immune response, especially the reactive oxygen species (ROS) released by phagocytic cells. To this aim, pathogens have developed various antioxidant systems, including superoxide dismutases (SODs) which constitute the first-line protection against oxidative stress. Interestingly, one of the S. apiospermum SOD-encoding genes (SODD gene) exhibits a glycosylphosphatidylinositol (GPI) anchor-binding site and encodes a conidial-specific surface SOD. In this study, a SODDΔ mutant was engineered from a non-homologous end joining-deficient strain (KU70Δ) of S. apiospermum. Compared to its parent strain, the double mutant KU70Δ/SODDΔ exhibited increased susceptibility to various oxidizing agents and triazole antifungals. In addition, the loss of SodD resulted in an increased intracellular killing of the conidia by M1 macrophages derived from human blood monocytes, suggesting the involvement of this superoxide dismutase in the evasion to the host defenses. Nevertheless, one cannot disregard an indirect role of the enzyme in the synthesis or assembly of the cell wall components since transmission electron microscopic analysis revealed a thickening of the inner cell wall layer of the conidia. Further studies are needed to confirm the role of this enzyme in the pathogenesis of Scedosporium infections, including the production of a recombinant protein and study of its protective effect against the infection in a mouse model of scedosporiosis.

Lower Funneling Pathways in Scedosporium Species

Lignin, a natural polyaromatic macromolecule, represents an essential component of the lignocellulose biomass. Due to its complexity, the natural degradation of this molecule by microorganisms still remains largely misunderstood. Extracellular oxidative degradation is followed by intracellular metabolic degradation of conserved aromatic intermediate compounds (protocatechuate, catechol, hydroxyquinol, and gentisic acid) that are used as carbon and energy sources. The lower funneling pathways are characterized by the opening of the aromatic ring of these molecules through dioxygenases, leading to degradation products that finally enter into the tricarboxylic acid (TCA) cycle. In order to better understand the adaptation mechanisms of Scedosporium species to their environment, these specific catabolism pathways were studied. Genes encoding ring-cleaving dioxygenases were identified in Scedosporium genomes by sequence homology, and a bioinformatic analysis of the organization of the corresponding gene clusters was performed. In addition, these predictions were confirmed by evaluation of the expression level of the genes of the gentisic acid cluster. When the fungus was cultivated in the presence of lignin or gentisic acid as sole carbon source, experiments revealed that the genes of the gentisic acid cluster were markedly overexpressed in the two Scedosporium species analyzed (Scedosporium apiospermum and Scedosporium aurantiacum). Only the gene encoding a membrane transporter was not overexpressed in the gentisic acid-containing medium. Together, these data suggest the involvement of the lower funneling pathways in Scedosporium adaptation to their environment.

Recent developments in less known and multi-resistant fungal opportunists

Fungal infections have increased in recent years due to host factors, such as oncohaematological and transplant-related disorders, immunosuppressive therapy, and AIDS. Additionally, molecular and proteomic facilities have become available to identify previously unrecognizable opportunists. For these reasons, reports on less-known and recalcitrant mycoses, such as those caused by black fungi, hyaline filamentous fungi, coelomycetes, Mucorales, and non-Candida yeasts have emerged. In this review, novel taxonomy in these groups, which often are multi-resistant to one or several classes of antifungals, is discussed. Clinical presentations, diagnosis and current treatment of some major groups are summarised.

Molecular epidemiology of Aspergillus species and other moulds in respiratory samples from Argentinean patients with cystic fibrosis

In cystic fibrosis (CF) patients, fungal colonization of the respiratory tract is frequently found. Aspergillus fumigatus is the most frequently recorded and is associated with loss of pulmonary function and allergic disease (ABPA). The knowledge on prevalence rates of filamentous fungi in CF patients in Latin America is scarce. One hundred and seventy-six fungal isolates recovered from the upper respiratory tract of CF patients from Argentina were identified to species by morphology and DNA sequencing. In total, 90% of CF patients were colonized by Aspergillus sp., followed by Exophiala sp. (14%) and Scedosporium sp. (10%). Among Aspergillus, six species complexes (Fumigati, Flavi, Terrei, Nigri, Usti, and Nidulante) and different cryptospecies were found. Among Scedosporium, three species were observed (Scedosporium apiospermum, Scedosporium aurantiacum and Scedosporium boydii). All Exophiala isolates were identified as Exophiala dermatitidis. Rare filamentous fungi were also found. All cases of ABPA were associated to the presence of A. fumigatus. Mixed colonization with other mould or rare fungi was observed in half of them. To our knowledge, this is the first prospective study of mould species in CF using molecular methods in Latin America. This study shows that Aspergillus sp., E. dermatitidis and Scedosporium sp. have a high frequency in CF patients from Argentina, and by far, A. fumigatus was the most commonly cultured species. Continuous clinical surveillance is required to detect the emergence of new fungal pathogens and to detect resistant or difficult-to-treat species capable of chronic colonizing the airways and of hematogenous dissemination in case of lung transplantation.

Clinical relevance of Scedosporium spp. and Exophiala dermatitidis in patients with cystic fibrosis: A nationwide study

An increased prevalence of various filamentous fungi in sputum samples of patients with cystic fibrosis (CF) has been reported. The clinical significance, however, is mostly unclear. The aim of this study was to investigate the clinical relevance of Scedosporium spp. and Exophiala dermatitidis from sputum samples of patients with CF in the Netherlands. In this cross-sectional study, all CF patients of the Dutch national CF registry who were treated at five of the seven recognized CF centers during a 3-year period were included. We linked clinical data of the national CF registry with the national Dutch filamentous fungal database. We investigated the association between clinical characteristics and a positive sputum sample for Scedosporium spp. and E. dermatitidis, using logistic regression. Positive cultures for fungi were obtained from 3787 sputum samples from 699 of the 1312 patients with CF. Scedosporium spp. was associated with severe genotype, CF-related diabetes, several microorganisms, and inhaled antibiotics. E. dermatitidis was associated with older age, female sex, and Aspergillus spp. CF patients with and without Scedosporium spp. or E. dermatitidis seemed comparable in body mass index and lung function. This study suggests that Scedosporium spp. and E. dermatitidis are probably no major pathogens in CF patients in the Netherlands. Greater understanding of epidemiologic trends, risk factors, and pathogenicity of filamentous fungi in the respiratory tracts of patients with CF is needed.

Scedosporium spp. from Clinical Setting in Argentina, with the Proposal of the New Pathogenic Species Scedosporium americanum

Species of the genus Scedosporium (family Microascaceae, phylum Ascomycota) are responsible for a wide range of opportunistic human infections, and have a low susceptibility to most antifungal drugs. It is well known that the pattern of Scedosporium species distribution varies according to geographic region. To assess the diversity of Scedosporium species in Argentina involved in human infections, we carried out a retrospective study reviewing 49 strains from clinical samples sent for diagnosis to the National Clinical Mycology Reference Laboratory between 1985 and 2019. Then, a phenotypic characterization, a phylogenetic study and and in vitro susceptibility test to antifungals were carried out. An analysis of combined nucleotide sequences dataset of the internal transcribed spacer of the ribosomal DNA (ITS) and of a fragment of the β-tubulin gene (BT2) demonstrated that 92% of the strains belonged to the species S. boydii, S. apiospermum and S. angustum, all them pertaining to S. apiospermum species complex. However, two strains (4%) were identified as S. aurantiacum, a species never reported in clinical settings in the Americas’. Surprisingly, one of them displayed a polycytella-like conidiogenesis, up to date only reported for S. apiospermum. In addition, the strain DMic 165285 was phylogenetically located far away from the rest of the species, so is proposed as the novel species Scedosporium americanum. On the other hand, from all seven antifungals tested, voriconazole and posaconazole were the most active drugs against Scedosporium spp.

Phenomic profiling of a novel sibling species within the Scedosporium complex in Thailand

Background

Scedosporium species are a group of pathogenic fungi, which can be found worldwide around high human-impacted areas. Infections of Scedosporium have been reported in several immunocompromised and immunocompetent patients with a high mortality rate. Recently, we have isolated and identified several Scedosporium strains during an environmental survey in Thailand.

Results

We describe the isolate, TMMI-012, possibly a new species isolated from soils in the Chatuchak public park, Bangkok, Thailand. TMMI-012 is phylogenetically related to the Scedosporium genus and is a sibling to S. boydii but shows distinct morphological and pathological characteristics. It is fast growing and highly resistant to antifungal drugs and abiotic stresses. Pathological studies of in vitro and in vivo models confirm its high virulence and pathogenicity.

Conclusion

TMMI-012 is considered a putative novel Scedosporium species. The high antifungal resistance of TMMI-012 compared with its sibling, Scedosporium species is likely related to its clinical impact on human health.

The Host Immune Response to Scedosporium/Lomentospora

Infections caused by the opportunistic pathogens Scedosporium/Lomentospora are on the rise. This causes problems in the clinic due to the difficulty in diagnosing and treating them. This review collates information published on immune response against these fungi, since an understanding of the mechanisms involved is of great interest in developing more effective strategies against them. Scedosporium/Lomentospora cell wall components, including peptidorhamnomannans (PRMs), α-glucans and glucosylceramides, are important immune response activators following their recognition by TLR2, TLR4 and Dectin-1 and through receptors that are yet unknown. After recognition, cytokine synthesis and antifungal activity of different phagocytes and epithelial cells is species-specific, highlighting the poor response by microglial cells against L. prolificans. Moreover, a great number of Scedosporium/Lomentospora antigens have been identified, most notably catalase, PRM and Hsp70 for their potential medical applicability. Against host immune response, these fungi contain evasion mechanisms, inducing host non-protective response, masking fungal molecular patterns, destructing host defense proteins and decreasing oxidative killing. In conclusion, although many advances have been made, many aspects remain to be elucidated and more research is necessary to shed light on the immune response to Scedosporium/Lomentospora.

Comparative transcriptome analysis unveils the adaptative mechanisms of Scedosporium apiospermum to the microenvironment encountered in the lungs of patients with cystic fibrosis

Scedosporium species rank second among the filamentous fungi colonizing the lungs of patients with cystic fibrosis (CF). Apart from the context of immunodeficiency (lung transplantation), the colonization of the CF airways by these fungi usually remains asymptomatic. Why the colonization of the lower airways by Scedosporium species is fairly tolerated by CF patients while these fungi are able to induce a marked inflammatory reaction in other clinical contexts remains questionable. In this regards, we were interested here in exploring the transcriptional reprogramming that accompanies the adaptation of these fungi to the particular microenvironment encountered in the airways of CF patients. Cultivation of Scedosporium apiospermum in conditions mimicking the microenvironment in the CF lungs was shown to induce marked transcriptional changes. This includes notably the down-regulation of enzymes involved in the synthesis of some major components of the plasma membrane which may reflect the ability of the fungus to evade the host immune response by lowering the biosynthesis of some major antigenic determinants or inhibiting their targeting to the cell surface through alterations of the membrane fluidity. In addition, this analysis revealed that some genes encoding enzymes involved in the biosynthesis of some mycotoxins were down-regulated suggesting that, during the colonization process, S. apiospermum reduces the production of some toxic secondary metabolites to prevent exacerbation of the immune system response. Finally, a strong up-regulation of many genes encoding enzymes involved in the degradation of aromatic compounds was observed, suggesting that these catabolic properties would predispose the fungus to particular patterns of human pathogenicity. Together these data provide new insights into the adaptative mechanisms developed by S. apiospermum in the CF lungs, which should be considered for identification of potential targets for drug development, but also for the experimental conditions to be used in in vitro susceptibility testing of clinical isolates to current antifungals.

Invasive Scedosporium and Lomentosora infections in the era of antifungal prophylaxis: A 20-year experience from a single centre in Spain

BACKGROUND

Non-Aspergillus mould infections such as those caused by Scedosporium apiospermum or Lomentospora prolificans are an emerging threat. Few studies have monitored their long-term incidence.

OBJECTIVES

To analyse the epidemiology, risk factors, clinical features and incidence of patients with proven and probable infections.

PATIENTS/METHODS

Patients admitted to Gregorio Marañón Hospital between 1998 and 2017 and from whom Scedosporium/Lomentospora was isolated were studied. Subjects were classified as having a probable/proven invasive fungal infection or colonization. Molecular identification and antifungal susceptibility testing of isolates causing infection were performed, as well as a description of the patients and incidence of infection.

RESULTS

One or more Scedosporium/Lomentospora isolates were identified in 67 patients. Sixteen (23.9%) patients had developed infection: 11 scedosporiosis and 5 lomentosporiosis. Stable incidence was observed throughout the study period. Most patients were immunosuppressed and the most common underlying diseases were haematologic malignancy (25%), solid organ transplantation (25%) and chronic corticoid therapy (25%). Breakthrough infection occurred in four patients, 2/11 (18.2%) cases of scedosporiosis and 2/5 (40%) of lomentosporiosis. Overall mortality was 54.5% (6/11) and 80% (4/5) in subjects with scedosporiosis and lomentosporiosis, respectively. High MICs of amphotericin B and remarkable inter-species susceptibility variability to triazoles was observed for most isolates.

CONCLUSIONS

In contrast to previous studies, the incidence of scedosporiosis and lomentosporiosis has not increased at our hospital over the years. The tendency to cause disseminated infection and a reduced susceptibility to most antifungal agents leads to high mortality.

Eradication of Lomentospora prolificans Osteomyelitis of the Wrist with Combination Antifungal Therapy, Voriconazole Bone Cement, and Surgical Debridement

Lomentospora prolificans is an emerging pathogen that is difficult to treat due to its intrinsic resistance to currently available antifungal agents. Current evidence demonstrates synergy between Azoles and Terbinafine against L. prolificans infections, while adjunct use of antifungal agent-loaded bone cement has also shown favourable outcomes. We report a case of an immunosuppressed adult with rheumatoid arthritis who developed L. prolificans osteomyelitis in his right wrist following trauma and subsequent exposure to commercially available fertiliser. The infection was successfully eradicated via a combination of aggressive, staged surgical source control, antifungal therapy using voriconazole and Terbinafine, and insertion of voriconazole-loaded bone cement into the wrist and carpus. The utility of this approach supports the synergistic effects of voriconazole and Terbinafine and, more broadly, the clinical benefits of antifungal-loaded bone cement, as demonstrated in previous case reports and in vitro studies. As such, combination antifungal therapy and voriconazole-loaded bone cement should be considered the therapy of choice in cases of osteomyelitis where L. prolificans is proven to be the causative organism.

An unusual case of Scedosporium apiospermum fungaemia in an immunocompetent patient with a left ventricular assist device and an implantable cardiac device

Left ventricular assist device (LVAD)-related infections are a leading cause of morbidity and mortality, with fungal infections being particularly difficult to manage. We report a case of an immunocompetent 39-year-old male with an LVAD and an implantable cardiac device (ICD) who developed fatal Scedosporium apiospermum fungaemia. To the best of our knowledge, this is the first reported case of LVAD-related S. apiospermum fungaemia.

Timing it right: the challenge of recipient selection for lung transplantation

Selection criteria for the referral and potential listing of patients for lung transplantation (LTx) have changed considerably over the last three decades but one key maxim prevails, the ultimate focus is to increase longevity and quality of life by careful utilization of a rare and precious resource, the donor organs. In this article, we review how the changes have developed and the outcomes of those changes, highlighting the impact of the lung allocation score (LAS) system. Major diseases, including interstitial lung disease (ILD), chronic obstructive pulmonary disease and pulmonary hypertension are considered in detail as well as the concept of retransplantation where appropriate. Results from bridging to LTx using extracorporeal membrane oxygenation (ECMO) are discussed and other potential contraindications evaluated such as advanced age, frailty and resistant infections. Given the multiplicity of risk factors it is a credit to those working in the field that such excellent and improving results are obtained with an ongoing dedication to achieving best practice.

Scedosporium species in soils from various biomes in Northwestern Morocco

Scedosporium species are opportunistic pathogens causing various infections, including disseminated infections in severely immunocompromised patients. Preventive measures aiming to reduce the risk of exposure to these fungi require a better knowledge on their ecology and on the sources of contamination of the patients. In this context, 99 soil samples from the Rabat-Sale-Kenitra and Fez-Meknes regions in Morocco were analyzed. Samples were inoculated on the highly selective Scedo-Select III culture medium, and seven chemical parameters of the soils were measured. Scedosporium species were detected in 48 of the samples, with the highest density in soils from wastewater treatment plants and landfills, followed by those from roadsides and polluted riverbanks, thus confirming the impact of human activities on their ecology. Scedosporium apiospermum was the most common species, followed by S. boydii and S. aurantiacum. Analysis of the chemical parameters of the soils revealed the presence of Scedosporium species was mainly associated with a moderate electrical conductivity, a pH range of 7.0 to 7.6, a nutrient-rich content and a moderate phosphorus amount. Thereby, these results demonstrated the relatively high occurrence of Scedosporium in Morocco and highlighted the impact of phosphorus content on their ecology.

Development of an immunocompetent murine model of pulmonary infection due to Scedosporium apiospermum

A pulmonary infection model due to Scedosporium apiospermum in immunocompetent mice was developed. BALB/c mice were infected by endotracheal intubation with 5 × 106 conidia/mouse and disease progression was evaluated on days 1, 3, 5, 7, 11, 16, 21, 30, 50 and 60 post-infection through quantitative culture and histopathological analysis of lungs, livers, spleens, brains, and kidneys. There was no extrapulmonary dissemination during the study nor shown to be a lethal infection. The fungal burden in lungs was maintained from day 1-5 and gradually decreased by day 30 post-challenge. On day 60, 30% of mice showed complete elimination of the fungus. Severe alterations in the lung tissue were observed, as well as the presence of conidia and hyphae surrounded by a cellular infiltrate composed mainly of neutrophils in the first days of the infection. The elimination of fungal cells and normal tissue morphology were recovered throughout the study.

Bioremediation of Olive Mill Wastewater sediments in evaporation ponds through in situ composting assisted by bioaugmentation

The common method for the disposal of olive oil mill wastewater (OMW) has been its accumulation in evaporation ponds where OMW sediments concentrate. Due to the phytotoxic and antimicrobial effect of OMW, leaks from ponds can pollute soils and water bodies. This work focuses on the search for microorganisms that can be used as inocula for bioremediation of polluted matrices in OMW ponds by means of in situ composting. Two fungi isolated from OMW sediments, Aspergillus ochraceus H2 and Scedosporium apiospermum H16, presented suitable capabilities for this use as a consortium. Composting eliminated the phyto- and ecotoxicity of OMW sediments by depleting their main toxic components. Inoculation with the fungal consortium improved the bioremediation efficacy of the technique by hastening the decrease of phytotoxicity and ecotoxicity and enhancing phytostimulant property of compost produced. This procedure constitutes a promising strategy for bioremediation of OMW polluted sites.

Advances in understanding and managing Scedosporium respiratory infections in patients with cystic fibrosis

Introduction: Considered for a long time to be exclusively responsible for chronic localized infections, fungi of the genus Scedosporium have recently received a renewed interest because of their recognition as common colonizing agents of the respiratory tract of patients with cystic fibrosis, and of the description of severe disseminated infections in patients undergoing lung transplantation. Recently, several studies have been carried out on these opportunistic pathogens, which led to some advances in the understanding of their pathogenic mechanisms and in the biological diagnosis of the airway colonization/respiratory infections caused by these fungi.Areas covered: From a bibliographic search on the Pubmed database, we summarize the current knowledge about the taxonomy of Scedosporium species, the epidemiology of these fungi and their pathogenic mechanisms, and present the improvements in the detection of the airway colonization and diagnosis of Scedosporium respiratory infections, the difficulties in their therapeutic management, and the antifungal drugs in development.Expert opinion: As described in this review, many advances have been made regarding the taxonomy and ecology of Scedosporium species or the molecular determinants of their pathogenicity, but also in the management of Scedosporium infections, particularly by improving the biological diagnostic and publishing evidence for the efficacy of combined therapy.

Scedosporium spp lung infection in immunocompetent patients: A systematic review and MOOSE-compliant meta-analysis

Scedosporium genus as a significant emerging opportunist causes a broad spectrum of disease in not only immunosuppressed but also immunocompetent patients. The lung is one of the most commonly encountered sites of Scedosporium infection. Due to its very high levels of antifungal resistance, surgery has been recommended as an important part in the treatment of pulmonary Scedosporium spp infection, even in immunocompetent cases. However, whether lung surgery could help to reduce the risk of death in immunocompetent patients is not clear.We retrospectively retrieved the records of pulmonary infections with Scedosporium species in immunocompetent patients through a comprehensive literature search. The association of surgery on all-cause mortality was explored using binary logistic regression (BLR). Receiver operating characteristic (ROC) curve analysis was carried out to evaluate the capability of the model.The comprehensive searching strategy yielded 33 case reports and 3 case series in total, with 40 individual patients being included. The overall mortality was 12.50%. The fatality rate was 9.09% (2/22) in cases with surgery and 16.67% (3/18) in cases without surgery (odds ratio, 0.50; 95% confidence interval, 0.07-3.38; P = .48). Consistently, BLR analysis identified no statistical association between surgery and reduced mortality (odds ratio, 1.19; 95% confidence interval, 0.09-15.64; P = .89), after adjusting for age, gender, and antifungal chemotherapy. The area under the ROC curve was 0.88.For immunocompetent patients with pulmonary Scedosporium spp infection, surgical therapy may not be associated with reduced mortality. Surgical excision could be considered but is not imperative in this group of patients.

Pulmonary scedosporiosis in a patient with acute hematopoietic failure: Diagnosis aided by next-generation sequencing

We report the first case of pulmonary scedosporiosis detected by next-generation sequencing (NGS) from bronchoalveolar lavage fluid (BALF) in a 67-year-old male with bronchiectasis and hematopoietic failure. Scedosporium apiospermum is a ubiquitous organism present in the environment with intrinsic resistance to many antifungal agents. The patient developed respiratory failure, pulmonary consolidation, and septic shock shortly thereafter, and responded poorly to antifungal therapy. This case highlights the combined application of NGS and traditional fungal culture in the clinical diagnosis of pulmonary invasive fungal disease. NGS is proposed as an important adjunctive diagnostic approach for uncommon pathogens.

Emerging fungal infections in solid organ transplant recipients: Guidelines of the American Society of Transplantation Infectious Diseases Community of Practice

These updated AST-IDCOP guidelines review the epidemiology, diagnosis, and management of emerging fungi after organ transplantation. Infections due to numerous generally innocuous fungi are increasingly recognized in solid organ transplant (SOT) recipients, comprising about 7%-10% of fungal infections in this setting. Such infections are collectively referred to as emerging fungal infections and include Mucormycetes, Fusarium, Scedosporium, and dematiaceous fungi among others. The causative organisms are diverse in their pathophysiology, uncommon in the clinical setting, have evolving nomenclature, and are often resistant to multiple commonly used antifungal agents. In recent years significant advances have been made in understanding of the epidemiology of these emerging fungal infections, with improved diagnosis and expanded treatment options. Still, treatment guidelines are generally informed by and limited to experience from cohorts of patients with hematological malignancies and/or solid and stem cell transplants. While multicenter randomized controlled trials are not feasible for these uncommon infections in SOT recipients, collaborative prospective studies can be valuable in providing information on the epidemiology, clinical manifestations, treatment strategies, and outcomes associated with the more commonly encountered infections.

[Scedosporium apiospermum infection in a kidney transplant recipient]

BACKGROUND

Emerging fungi infections, although being not the most frequent, are a cause of major morbidity and mortality in recipients of solid organ transplants. The infections caused by the fungi Scedosporium apiospermum are a paradigmatic example of these.

CASE REPORT

We present the clinical case of a 55 year-old female kidney transplant recipient that got infected with S. apiospermum through the skin. Intensive antifungal therapy was started, especially considering that the patient had an arteriovenous fistula at the site of infection. The fungus could have kept in the fistula, and a subsequent reinfection took place. The patient required both medical and surgical treatment (removal of the prosthetic material), that led to a complete recovery.

CONCLUSIONS

S. apiospermum infections carry a high risk of complications, and are a frequent cause of morbidity and mortality in immunosuppressed/transplant patients. Therefore, the adequate knowledge of this type of mycosis, as well as the making of an adequate differential diagnosis, become fundamental for the prevention of the complications arising from them.

Inhaled antibiotic use is associated with Scedosporium/Lomentospora species isolation in cystic fibrosis

INTRODUCTION

Prevalence of fungi has been rising in the cystic fibrosis (CF) population. Scedosporium species (spp) is the second most common mold seen in the CF respiratory tract. However, the characteristics associated with Scedosporium isolation and its clinical implications are poorly understood. The goal of this study was to determine clinical factors associated with Scedosporium spp to better understand the mechanisms that may contribute to the emergence of filamentous fungi in CF.

METHODS

We conducted a retrospective cohort study of subjects followed in the CF Foundation Patient Registry between January 1, 2010 and December 31, 2012. Patients under 6 years of age, history of solid organ transplantation, and insufficient respiratory culture data were excluded. We used a multivariable logistic regression model to determine demographic data and baseline disease characteristics, medications and co-infections associated with Scedosporium spp recovery in CF sputum.

RESULTS

Among 19 023 subjects, prevalence of Scedosporium spp was 615 (3.2%). Older age (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.07, 1.26) and white race (OR 1.69, 95% CI 1.09, 2.63) were the demographic factors associated with Scedosporium spp isolation. Inhaled antibiotic use had a significant association with Scedosporium isolation (OR 2.01, 95% CI 1.61, 2.52). For every additional course of intravenous antibiotics, the odds of Scedosporium isolation increased by 8% (OR 1.08, 95% CI 1.03, 1.14).

CONCLUSIONS

The association between inhaled antibiotics and Scedosporium informs us that chronic inhaled antibiotics may be playing a role in Scedosporium isolation. Further investigation to better characterize this relationship is necessary.