Analysis of the Efficacy and Renal Prognosis of a Reduced-Dose Immunosuppressive Regimen of Mild to Moderate ANCA-Associated Renal Vasculitis

Objectives: Secondary infection caused by high-dose immunosuppressive therapy is one of the most common causes of death in patients with ANCA-associated vasculitis. This study aimed to explore whether reduced-dose immunosuppressive therapy can achieve the same efficacy while reducing secondary infection in mild to moderate ANCA-associated renal vasculitis and to determine whether early secondary infections will affect the deterioration of renal function. Methods: The efficacy and safety of the reduced-dose regimen and standard regimen were compared using the chi-square test. The renal survival rates were estimated using the Kaplan–Meier method and compared using the log rank test. Potential variates were examined using multivariate Cox proportional hazard models to determine the risk predictors of end-stage renal disease. Results: A total of 35 patients in the standard-dose glucocorticoid group and 23 in the reduced-dose glucocorticoid group were included. The average age of the included patients was 62.45±12.70 years, and the baseline serum creatinine was 251.35 [155.53, 445] μmol/L. Nine patients (15.52%) developed ESRD within 24 months (7 standard vs. 2 reduced, P=0.035). Multivariate Cox regression model analysis proved that baseline serum creatinine (HR: 0.007, 95% CI: 2.48-39.48, P=0.014), secondary infection rate within the first 3 months (HR: 2.28, 95% CI: 2.14 45.27, P=0.003), and persistent hematuria for more than 6 months (HR: 1.723, 95% CI: 0.043-0.738, P=0.017) were risk predictors of end-stage renal disease in ANCA-associated renal vasculitis. Conclusion: The regimen of initial reduced-dose immunosuppressive therapy can significantly reduce the secondary infection rate in mild to moderate ANCA-associated renal vasculitis patients, and the efficacy is not inferior to the standard regimen. Patients who had secondary infection within the first 3 months were at higher risk of developing ESRD.