Comparative analysis of gut microbiota in incident and prevalent peritoneal dialysis patients with peritoneal fibrosis, correlations with peritoneal equilibration test data in the peritoneal fibrosis cohort.

Introduction: The connection between peritoneal function and gut microbiota in peritoneal fibrosis (PF) patients remains uncertain.

Methods: Peritoneal equilibration test (PET) was employed to evaluate peritoneal function in patients with peritoneal fibrosis (PF). 16S rRNA sequencing was used to analyze the gut flora in incident peritoneal dialysis (PD) and PF groups, identifying differential microbial communities. Spearman's correlation analysis, conducted using SPSS 26.0, was employed to explore the microbial associations with PF.

Results: In the PF group, the PET showed a 4-h dialysate-to-plasma creatinine ratio (D/PCr) ratio of 0.62 ± 1.01 and a 4-h ultrafiltration (UF) volume of 41.73 ± 76.71 mL with a 2.5% glucose dwell. The alpha diversity between the PD and PF groups did not exhibit a significant difference. The PD and PF groups were predominantly composed of Firmicutes, Tenericutes, and Ignavibacteriae. Linear discriminant analysis effect size (LEfse) analysis indicates that the Firmicutes, Lactobacillales, and Bacilli were significantly enriched in the PD group, whereas Lachnospiraceae, Phenylobacterium, and Caulobacteraceae were enriched among the PF group. The functional prediction of gut microbiota genes revealed variations in metabolic pathways related to lipid transport, energy metabolism, and post-translational protein modifications between the two cohorts. In the PF group, Ignavibacteriae and Bdellovibrio correlated positively with the 4-h D/PCr ratio (p <0.05), while Prevotella negatively correlated with the 4-h UF from 2.5% glucose dwell (p <0.05).

Conclusion: The intestinal microbiota of patients newly initiated on peritoneal dialysis significantly differs from that of those with long-term peritoneal dialysis complicated by peritoneal fibrosis, with the latter's peritoneal function potentially linked to Prevotella, Ignavibacteriae, and Bdellovibrio.