Role of light chain clearance in the recovery of renal function in multiple myeloma: another point of view

Abstract Background Acute Kidney Injury (AKI) in patients with multiple myeloma (MM) requiring renal replacement treatment (RRT) is associated with high morbidity and mortality. Early reduction of serum free light chains (FLC) using both targeted therapy against MM and intensive hemodialysis (IHD) may improve renal outcomes. We evaluated the effectiveness of two different RRT techniques on renal recovery in a MM patient population: standard dialysis procedure versus IHD with either PMMA or hemodiafiltration with endogenous reinfusion (HFR). Methods Multicentric retrospective study with severe AKI related to MM, between 2011 and 2018. Twenty-five consecutive patients with AKI secondary of MM requiring RRT were included. Patients that underwent IHD received 6 dialysis sessions per week during the first 14 days (PMMA vs HFR). All patients were diagnosed with de novo MM or first relapsed MM. Primary outcome was renal recovery defined as dialysis-free at six months follow-up. Results A total of 25 patients were included. Seventeen patients received IHD and 8 standard dialysis. All patients were treated with targeted therapy, 84% bortezomib-based. Of the 25 patients included, fourteen (56%) became dialysis independent. We observed a higher proportion of patients who received IHD in the group who recovered kidney function compared to those who remained in HD (92.9% vs 36.4%, p:0.007). In our study, the use of IHD to remove FLC had a statistically significant association with renal recovery compared to standard dialysis group (p = 0.024). Conclusion Early reduction of FLC with IHD as an adjuvant treatment along with MM targeted therapy may exert a positive impact on renal recovery.