#1908 Characterization of the gut mycobiome composition in patients with end-stage renal disease

Abstract Background and Aims The serum uremic toxins of end-stage renal disease (ESRD) patients is intricately linked to the metabolism of gut microbiota. Despite the pivotal role played by gut mycobiome in the pathogenesis of several renal diseases, limited investigations have been conducted on its involvement in ESRD patients, including dialysis and pre-dialysis individuals. Therefore, the objective of this study is to gain further insights into the alterations occurring in the gut mycobiome of ESRD patients, aiming to provide novel strategies for improving the prognosis of these patients. Method This is an observational retrospective study. A total of 200 fecal samples were collected from each participant, including 51 healthy controls (HC), 51 pre-dialysis (ND) patients, 42 hemodialysis (HD) patients, and 56 peritoneal dialysis (PD) patients. Gut mycobiome was analyzed using the internal transcribed spacer region (ITS) ribosomal RNA gene sequencing. Additionally, we conducted spearman correlation analysis to identify associations between differential fungi and clinical parameters in ESRD patients, including both dialysis and pre-dialysis individuals. Results In comparison with healthy controls, ESRD patients exhibited a significant reduction in alpha diversity of the gut mycobiome. At the phylum level, ESRD patients had a significantly decreased relative abundance of Ascomycota and Basidiomycota, and an increased relative abundance of Fungi_phy_Incertae_sedis. Although there was no significant difference in mycobiome diversity between pre-dialysis and dialysis patients, differential fungi were observed at the taxonomic level between the two groups. Similarly, differential fungi were also found when comparing hemodialysis and peritoneal dialysis patients. Importantly, we observed a linear correlation between the abundance of differential fungi and kidney function, suggesting a potential interaction between these fungi with kidney function. Conclusion This study demonstrated the diversity and composition of the gut mycobiome are significantly altered in ESRD patients. Dialysis therapy affects the relative abundance of fungi at the taxonomic level. These findings suggest potential implications of specific fungal species on kidney function.