To investigate the diversity and composition of gut fungi microbiota in patients with polycystic kidney disease (PKD) and its correlation with clinical indicators.

A total of 44 PKD patients, 44 patients with non-polycystic chronic kidney disease (NPCKD) and 22 healthy controls (HC) admitted to our hospital from February 2023 to February 2024 were recruited. ITS1 DNA sequencing was applied to analyze the gut fungal composition. Bioinformatics analysis was used to compare the diversity and structural differences of fungi among the 3 groups. Pearson correlation analysis was performed to analyze the relationship between gut fungi and clinical indicators.

There were no significant differences in baseline characteristics (gender, age, body mass index, etc.) among the 3 groups, but statistical differences were seen in terms of serum indicators (such as serum creatinine, blood urea nitrogen, uric acid, estimated glomerular filtration rate, etc.) (P < 0.01). Alpha diversity analysis showed no significant difference was seen between the PKD and HC groups, but the PKD group had significant differences to the NPCKD group (P < 0.01). Beta diversity analysis revealed significant differences among the 3 groups and in pairwise comparisons (P=0.001). Fungi composition analysis found that the abundance of Candida was significantly higher in the PKD group than the other 2 groups (P < 0.01), while the abundances of Aspergillus and Cladosporium were significantly lower in the PKD group than the HC group (P < 0.05). Linear discriminant analysis (LEFSe) indicated that Candida was significantly enriched, while Aspergillus and Cladosporium were significantly reduced in the PKD group. Correlation analysis revealed that the abundance of Cladosporium was negatively correlated with cyst diameter and immunoglobulin light chain Kappa/Lambda ratio in the PKD group (P < 0.05), while the abundance of Candida was positively correlated with liver/kidney cyst diameter (P < 0.01).

PKD patients exhibit characteristic changes in gut fungi diversity and composition. The abundances of Cladosporium and Candida are closely associated with clinical indicators of PKD patients.