Efficacy of Immunomodulatory Drugs in Combination With Dexamethasone in Proliferative Glomerulonephritis With Monoclonal Immunoglobulin Deposits

INTRODUCTION: Immunomodulatory drugs (IMiDs) plus dexamethasone are effective for plasma cell dyscrasias, but the treatment efficacy of IMiD in proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) has been rarely reported. METHODS: We retrospectively analyzed the clinicopathologic data of 64 patients with PGNMID (steroid, IMiD, and bortezomib and dexamethasone/Rituximab [BD/RTX] groups) from January 1, 2010 to December 31, 2020, at the National Clinical Research Center of Kidney Disease in Nanjing. The prognosis of patients receiving different treatment regimens were compared. Factors potentially affecting renal prognosis and renal response were evaluated. RESULTS: Twenty-eight, 26 and 10 PGNMID patients were divided into IMiD group, steroid group and BD/RTX group respectively. The rate of serum M protein detection was significantly lower in the steroid group than in the other 2 groups. Renal remission (P = 0.001 and P = 0.03, respectively) rates and renal complete remission (CR) (P = 0.001 and P = 0.01, respectively) rates were significantly higher in the IMiD and BD/RTX groups than in the steroid group at the last follow-up. Multivariate logistic analysis identified that hypertension and high serum creatinine (SCr) levels (>1.24 mg/dl) decreased renal remission, whereas low C3 levels, IMiD and BD/RTX treatments were positively associated with renal remission. Multivariate Cox analysis identified IgG3 in renal tissue and high SCr levels as poor renal prognostic indicators. Severe adverse events were more common in the IMiD and BD/RTX groups than in the steroid group (P = 0.072 and P = 0.035, respectively). CONCLUSION: Our results suggest that IMiDs plus dexamethasone is effective for achieving renal remission in PGNMID patients.