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Sun, P.-L.

Publications and source records attributed to Sun, P.-L..

3 recordsLinked to original sources

Phylogenetic Insights into Antifungal Susceptibility: Comparing Environmental and Clinical Scedosporium and Lomentospora Isolates from Taiwan

ObjectivesScedosporium and Lomentospora species are intrinsically resistant molds increasingly implicated in invasive infections with poor outcomes. Olorofim, a novel orotomide antifungal, has demonstrated potent activity against various molds. This study evaluated the antifungal susceptibility of clinical and environmental isolates, focusing on olorofim, and examined these data in a phylogenetic context. MethodsA total of 216 isolates (Scedosporium spp., n=205; L. prolificans, n=11) were collected from clinical and environmental sources across Taiwan. Species identification was confirmed by sequencing of the ITS and {beta}-tubulin regions, followed by maximum-likelihood phylogenetic analysis. Antifungal susceptibility was determined using CLSI M38-A3 method. Cross-resistance was evaluated using correlation analyses. Phylogenetic signal, Mantel tests, and variance partitioning were applied to assess the evolutionary structuring of minimum inhibitory concentrations (MICs). ResultsScedosporium apiospermum (46.3%) and S. boydii (15.7%) were the predominant species, exhibiting comparable triazole susceptibility profiles (MIC90: voriconazole 1-2 mg/L, posaconazole 4 mg/L, and isavuconazole 8 mg/L). L. prolificans displayed pan-resistance to all agents except olorofim. Among triazoles, voriconazole yielded the lowest MICs for most Scedosporium isolates. Olorofim exhibited the lowest MICs across Scedosporium spp. and L. prolificans (all MIC90 [≤]0.12 mg/L). Rare taxa (S. marinum, S. haikouense, S. multisporum, S. minutisporum, S. sp. nov.1) were also identified, exhibiting variable triazole MICs but consistently low olorofim MICs. The association between antifungal susceptibility and species relatedness varied by drug: moderate for posaconazole, amphotericin B, and voriconazole; intermediate for olorofim; weak for isavuconazole; and absent for itraconazole. Most MIC variability (72.5-89.2%) occurred within rather than between species. ConclusionsAntifungal susceptibility among Scedosporium spp. and L. prolificans was drug dependent. Olorofim demonstrated consistently low MICs across species, whereas amphotericin B and triazoles showed variable, species-specific activity. These findings highlight olorofim as a promising therapeutic option and emphasize the need for target gene-based investigations to elucidate the evolutionary basis of antifungal resistance.

microbiology↗

Human activity, not environmental factors, drives Scedosporium and Lomentospora distribution in Taiwan

Scedosporium and Lomentospora species are emerging fungal pathogens capable of causing severe infections in both immunocompetent and immunocompromised individuals. Previous environmental surveys have suggested potential associations between these fungi and various soil chemical parameters, though the relative influence of human activity versus environmental factors has not been systematically evaluated. Here, we conducted a comprehensive survey of 406 soil samples from 132 locations across Taiwan, analyzing fungal abundance alongside soil physicochemical parameters and the Human Footprint Index (HFI). We recovered 236 fungal isolates comprising 10 species, with S. boydii (32.2%), S. apiospermum (30.9%), and S. dehoogii (14.4%) being the most prevalent. The highest fungal burdens were observed in urban environments (up to 1293 CFU/g), particularly in public spaces and healthcare facilities. Statistical analysis revealed a significant positive correlation between fungal abundance and HFI (r = 0.125, p = 0.013), while soil chemical parameters including nitrogen, carbon, pH, electrical conductivity, and various base cations showed no significant associations despite their wide ranges. These findings indicate that anthropogenic disturbance of environments, rather than soil chemistry, is the primary driver of Scedosporium and Lomentospora distribution in Taiwan. This understanding holds important implications for predicting infection risks and developing targeted public health strategies, particularly in rapidly urbanizing regions. Future studies incorporating more specific indicators of human impact may further elucidate the mechanisms underlying these distribution patterns. Lay AbstractWe found that human activities, rather than soil properties, determine where Scedosporium/Lomentospora fungi distribute in Taiwan. These fungi are more abundant in urban areas than less-human-disturbed environments, suggesting increased infection risks in densely populated regions.

ecology↗

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 130 out of 271 soil samples (47.9%) across Taiwan. We morphologically and molecularly identified five Scedosporium species and one Lomentospora species. All four major clinical relevant species were isolated with high frequency, i.e. S. apiospermum (42.5%), S. boydii (27.5%), L. prolificans (15.0%), and S. aurantiacum (8.8%); two clinically minor species, S. dehoogii (5.6%) and S. haikouense (0.6%), had moderate incidence. These fungal species have high incidence in urban (48%) and hospital (67.4%) soil samples, and have 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 to natural sites. In addition, strong evidence suggested that the distribution and abundance of these fungal species are highly heterogeneous in the environment; samples in vicinity often yield varied fungal communities. Our results indicated that these fungal species are prevalent in soil in Taiwan and their occurrences are associated with human activities. Hygiene sensitive places such as hospitals should be particularly aware of the high frequency of the clinical relevant species.

microbiology↗