Extracorporeal light chain elimination: high cut-off (HCO) hemodialysis parallel to chemotherapy allows for a high proportion of renal recovery in multiple myeloma patients with dialysis-dependent acute kidney injury

Acute kidney injury (AKI) is frequent in multiple myeloma (MM) patients and strongly affects prognosis, with particularly poor outcomes in patients requiring hemodialysis. Introduction of the novel therapeutic agents to MM therapy has improved myeloma response and renal outcome. This case series reviews the efficacy of combined systemic and extracorporeal therapy to further optimize time to light chain (serum-free light chain (sFLC)) reduction and renal recovery in MM patients with dialysis-dependent AKI (n = 19). High cut-off (HCO) hemodialysis for extracorporeal sFLC removal was initiated in parallel to chemotherapy. Combined therapy resulted in early sFLC response after a median of 13 (range 4-48) days and 6 (3-22) HCO hemodialysis sessions. Time to sFLC response was shorter in patients recovering renal function. Median time to dialysis independence was 15 (4-64) days. By intent-to-treat analysis, sustained renal recovery was achieved in 73.7% (77.8% adjusted for death) of patients. In multivariate analysis, duration of AKI prior to initiation of therapy was an independent predictor of renal functional outcome. Combining HCO hemodialysis for extracorporeal sFLC elimination and effective chemotherapy is a novel treatment strategy allowing for early and sustained sFLC reduction and a high proportion of renal recovery in these patients. Timely diagnosis and onset of therapy is essential for improving renal outcome.