Prognostic significance of soluble urokinase-type plasminogen activator receptor in patients with glomerulonephritis: association with renal outcomes.

BACKGROUND

We investigated the association of longitudinally assessed soluble urokinase-type plasminogen activator receptor (suPAR) levels and renal outcomes in patients with glomerulonephritis (GN).

METHODS

This study included 96 patients diagnosed with primary GN by renal biopsy during 2013-2020 at two tertiary hospitals. Serum suPAR levels were measured at biopsy and follow-up. The association between serum suPAR levels and renal outcomes was analyzed.

RESULTS

Ln(suPAR) levels at the time of biopsy were comparable among GN groups (p = 0.49). Significant reductions in Ln(suPAR) from baseline to follow-up were observed across all GN groups during a median of 2.3 years of follow-up (p < 0.05). The annual proportional change in Ln(suPAR) (%/year) differed significantly among the four GN groups (p < 0.001), with immunoglobulin A nephropathy showing the greatest reduction rate compared to focal segmental glomerulosclerosis (p < 0.001) and membranous nephropathy (p = 0.045). Kaplan-Meier analysis showed that patients in the highest tertile of Ln(suPAR) at biopsy had a significantly higher incidence of kidney function decline (p = 0.03), whereas the incidences of no reduction in proteinuria and achieving a ≥50% reduction in proteinuria did not differ significantly among tertiles (p = 0.72 and p = 0.07, respectively). Higher Ln(suPAR) levels at biopsy were significantly associated with an increased risk of declining estimated glomerular filtration rate (eGFR) in a Cox proportional hazards model (hazard ratio, 1.87; 95% confidence interval, 1.01-3.47; p = 0. 047).

CONCLUSION

In patients with biopsy-proven primary GN, higher suPAR levels at biopsy independently predicted subsequent eGFR decline but not proteinuria change, supporting longitudinal suPAR assessment as a complementary tool for renal risk stratification.