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Scedosporium and Lomentospora species are the second most frequent colonizing, allergenic, or invasive fungal pathogens in patients with cystic fibrosis, and are responsible for infections varying from cutaneous and subcutaneous tissue infections caused by traumatic inoculation to severe systemic diseases in immunocompromised patients. The clinical relevance of fungal airway colonization for individual patients harboring Scedosporium and Lomentospora species is still an underestimated issue. The high resistance of Scedosporium and Lomentospora species to antifungal drugs has highlighted the need for alternative treatment modalities, and antimicrobial photodynamic therapy may be one such alternative. In this study, methylene blue was applied as a photosensitizing agent to 6 type strains of Scedosporium and Lomentospora species, and we irradiated the strains using a light-emitting diode (635 ± 10 nm, 12 J/cm2). We evaluated the effects of photodynamic therapy on strain growth and on the in vitro susceptibility of the strains to itraconazole, voriconazole, posaconazole, and amphotericin B. A colony-forming unit reduction of up to 5.2 log10 was achieved. Minimal inhibitory concentration ranges also decreased significantly with photoinactivation. Photodynamic therapy improved both the inactivation rates and the antifungal susceptibility profile of all fungal isolates tested.

International audience; As a result of fundamental changes in the International Code of Nomenclature on the use of separate names for sexual and asexual stages of fungi, generic names of many groups should be reconsidered. Members of the ECMM/ISHAM working group on Pseudallescheria/Scedosporium infections herein advocate a novel nomenclature for genera and species in Pseudallescheria, Scedosporium and allied taxa. The generic names Parascedosporium, Lomentospora, Petriella, Petriellopsis, and Scedosporium are proposed for a lineage within Microascaceae with mostly Scedosporium anamorphs producing slimy, annellidic conidia. Considering that Scedosporium has priority over Pseudallescheria and that Scedosporium prolificans is phylogenetically distinct from the other Scedosporium species, some name changes are proposed. Pseudallescheria minutispora and Petriellidium desertorum are renamed as Scedosporium minutisporum and S. desertorum, respectively. Scedosporium prolificans is renamed as Lomentospora prolificans.

Infections of Exophiala spp. and Fusarium spp. are often chronic and recalcitrant. Systemic disseminations, which mostly occur in immunocompromised patients, are often refractory to available antifungal therapies. The conserved target of rapamycin (TOR) orchestrates cell growth and proliferation in response to nutrients and growth factors, which are important for pathogenicity and virulence. INK128 is a second-generation ATP-competitive TOR inhibitor, which binds the TOR catalytic domain and selectively inhibits TOR. In the present study, we investigated the in vitro activities of INK128 alone and the interactions of INK128 with conventional antifungal drugs including itraconazole, voriconazole, posaconazole, and amphotericin B against 18 strains of Exophiala spp. and 10 strains of Fusarium spp. via broth microdilution checkerboard technique system adapted from Clinical and Laboratory Standards Institute broth microdilution method M38-A2. INK128 alone was inactive against all isolates tested. However, favorable synergistic effects between INK128 and voriconazole were observed in 61% Exophiala strains and 60% Fusarium strains, despite Fusarium strains exhibited high MIC values (4–8 μg/ml) against voriconazole. In addition, synergistic effects of INK128/itraconazole were shown in 33% Exophiala strains and 30% Fusarium strains, while synergy of INK128/posaconazole were observed in 28% Exophiala strains and 30% Fusarium strains. The effective working ranges of INK128 were 0.125–2 μg/ml and 1–4 μg/ml against Exophiala isolates and Fusarium isolates, respectively. No synergistic effect was observed when INK128 was combined with amphotericin B. No antagonism was observed in all combinations. In conclusion, INK128 could enhance the in vitro antifungal activity of voriconazole, itraconazole and posaconazole against Exophiala spp. and Fusarium spp., suggesting that azoles, especially voriconazole, combined with TOR kinase inhibitor might provide a potential strategy to the treatment of Exophiala and Fusarium infections. However, further investigations are warranted to elucidate the underlying mechanism and to determine possible reliable and safe application in clinical practice.

The PCR-RLB (reverse line blot hybridisation) was applied as a molecular technique for the detection of members of Pseudallescheria and Scedosporium from sputum of patients with cystic fibrosis (CF). Fifty-nine sputum samples were collected from 52 CF patients, which were analysed by culture and PCR-RLB. Conventional and semi-selective culture yielded five positive samples, but the PCR-RLB hybridisation assay permitted the detection of members of Pseudallescheria/Scedosporium in 32 out of 52 patients (61.5%). In total, PCR-RLB yielded 47 positives. Pseudallescheria apiosperma was detected in 20 samples, while Pseudallescheria boydii and Pseudallescheria aurantiacum were detected in 17 and eight samples, respectively. Six samples gave a positive reaction with two distinct species-specific probes and one sample with three probes. In conclusion, the PCR-RLB assay described in this study allows the detection of Scedosporium spp. in CF sputum samples and the identification of Pseudallescheria apiosperma, P. boydii, S. aurantiacum, Scedosporium prolificans and Pseudallescheria minutispora.

The Pseudallescheria boydii complex, comprising environmental pathogens with Scedosporium anamorphs, has recently been subdivided into five main species: Scedosporium dehoogii , S. aurantiacum , Pseudallescheria minutispora , P. apiosperma , and P. boydii , while the validity of some other taxa is being debated. Several Pseudallescheria and Scedosporium species are indicator organisms of pollution in soil and water. Scedosporium dehoogii in particular is enriched in soils contaminated by aliphatic hydrocarbons. In addition, the fungi may cause life-threatening infections involving the central nervous system in severely impaired patients. For screening purposes, rapid and economic tools for species recognition are needed. Our aim is to establish rolling circle amplification (RCA) as a screening tool for species-specific identification of Pseudallescheria and Scedosporium . With this aim, a set of padlock probes was designed on the basis of the internal transcribed spacer (ITS) region, differing by up to 13 fixed mutations. Padlock probes were unique as judged from sequence comparison by BLAST search in GenBank and in dedicated research databases at CBS (Centraalbureau voor Schimmelcultures Fungal Biodiversity Centre). RCA was applied as an in vitro tool, tested with pure DNA amplified from cultures. The species-specific padlock probes designed in this study yielded 100% specificity. The method presented here was found to be an attractive alternative to identification by restriction fragment length polymorphism (RFLP) or sequencing. The rapidity (

Disseminated infections caused by Trichosporon asahii are difficult to resolve. Combination regimens with synergistic drugs could provide additional options for treating trichosporonosis. The aim of this study was to evaluate the antifungal activities of voriconazole (VCZ), caspofungin (CAS) and amphotericin B (AMB) alone or in combination in vitro against clinical isolates of T. asahii. The combined antifungal activities of VCZ, CAS and AMB against 18 clinical isolates were assessed by a chequerboard microdilution method. CAS combined with AMB showed the highest percentage of synergistic effects (89%), much higher than those of the other two combinations (AMB/VCZ and CAS/VCZ both 17%). No antagonistic effect was observed in any case. This study demonstrates that the activity of two combined antifungals, especially the combination of CAS and AMB, against T. asahii is more effective than that of a drug alone against this fungus, suggesting that combined antifungal therapy may be a potential strategy for treating disseminated trichosporonosis.

The major clinically relevant species in Scedosporium (teleomorph Pseudallescheria ) are Pseudallescheria boydii , Scedosporium aurantiacum , Scedosporium apiospermum , and Scedosporium prolificans , while Pseudallescheria minutispora , Petriellopsis desertorum , and Scedosporium dehoogii are exceptional agents of disease. Three molecular methods targeting the partial β-tubulin gene were developed and evaluated to identify six closely related species of the S. apiospermum complex using quantitative real-time PCR (qPCR), PCR-based reverse line blot (PCR-RLB), and loop-mediated isothermal amplification (LAMP). qPCR was not specific enough for the identification of all species but had the highest sensitivity. The PCR-RLB assay was efficient for the identification of five species. LAMP distinguished all six species unambiguously. The analytical sensitivities of qPCR, PCR-RLB, and LAMP combined with MagNAPure, CTAB (cetyltrimethylammonium bromide), and FTA filter (Whatman) extraction were 50, 5 × 10 3 , and 5 × 10 2 cells/μl, respectively. When LAMP was combined with a simplified DNA extraction method using an FTA filter, identification to the species level was achieved within 2 h, including DNA extraction. The FTA-LAMP assay is therefore recommended as a cost-effective, simple, and rapid method for the identification of Scedosporium species.