Efficacy of Prednisone Combined with Leflunomide in Lupus Nephritis and the Prognostic Value of TL1A and Serum Cystatin C

Abstract

Introduction. To evaluate the therapeutic efficacy of prednisone combined with leflunomide in patients with lupus nephritis (LN) and investigate the prognostic value of serum tumor necrosis factor-like ligand 1A (TL1A) and cystatin C.
Methods. This study included 64 patients with LN treated with prednisone and leflunomide between June 2020 and March 2022 
and 64 healthy controls. Serum TL1A and cystatin C levels were measured before and after treatment. Clinical and laboratory 
parameters were compared, and the predictive values of TL1A and cystatin C for treatment response and prognosis were 
assessed using ROC analysis. Independent prognostic factors were identified by multivariate analysis.
Results. Before treatment, serum TL1A and cystatin C levels were significantly higher in patients with LN than in healthy controls (P < .05). Both biomarkers decreased significantly after treatment but remained above control levels (P < .05). Treatment also 
significantly reduced 24-hour urinary protein, serum creatinine, and BUN, while increasing serum albumin and complement C3 
(P < .05). Baseline TL1A and cystatin C levels were significantly lower in patients with an effective treatment response than in 
those with ineffective treatment (P < .05). ROC analysis showed good predictive performance for treatment response  and prognosis. Multivariate analysis identified elevated 
24-hour proteinuria, serum cystatin C, TL1A, and higher renal pathological grade as independent predictors of poor prognosis.
Conclusions. Serum cystatin C and TL1A are promising biomarkers for predicting treatment response and prognosis in LN patients receiving prednisone plus leflunomide. Elevated levels of both biomarkers are independently associated with poor clinical outcomes.