Roles of Serum NLRP3 Inflammasome and Associated Cytokines in Gout-Induced Kidney Injury.

INTRODUCTION

Gout, characterized by hyperuricemia and urate crystal deposition, is associated with systemic inflammatory complications, including kidney injury. This study aimed to investigate the role of serum nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome and associated cytokines (IL-1β and IL-18) in gout-related kidney injury (GRI).

METHODS

A total of 279 gout patients (96 with renal injury and 183 without renal injury) and 100 healthy controls were included. Serum NLRP3, IL-1β, and IL-18 were measured and compared using an enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) analysis was carried out to evaluate the diagnostic values of individual or combinational biomarkers. Spearman's correlation analysis was employed to analyze correlations between NLRP3, IL-1β, and IL-18 and renal function indicators or serum uric acid.

RESULTS

Serum levels of NLRP3, IL-1β, and IL-18 were significantly higher in gout patients compared to healthy controls (p < 0.001, gout group with kidney injury [GKI]: n = 96, gout group without kidney injury [GNKI]: n = 183, controls: n = 100), with elevated levels observed in GKI patients compared to GNKI (p < 0.001). Correlations between these markers were confirmed among all gout patients (n = 279), including serum NLRP3 with IL-1β (r = 0.34, p < 0.001) and NLRP3 with IL-18 (r = 0.47, p < 0.001). ROC analysis revealed that the combined model of NLRP3, IL-1β, and IL-18 showed improved diagnostic accuracy for GRI, with an AUC of 0.85 (95% CI: 0.81-0.89, p < 0.001). In GKI patients (n = 96), serum NLRP3, IL-1β, and IL-18 were inversely correlated with eGFR (NLRP3: r = -0.43, p < 0.01). Additionally, serum IL-18 positively correlated with serum uric acid levels (r = 0.27, p = 0.009).

CONCLUSION

These findings highlight the potential of serum NLRP3, IL-1β, and IL-18 as diagnostic markers and therapeutic targets in GRI, providing insights into early intervention and improved clinical outcomes in gout patients with renal complications.