High Cut-Off Hemodialysis for Myeloma Cast Nephropathy – Do We Finally Have An Answer?

Abstract

The most common kidney presentation in patients with multiple myeloma (MM) is acute kidney injury (AKI) from cast nephropathy. Patients have a poorer 1 year survival compared to patients free of kidney involvement. The key to treating cast nephropathy is rapid reduction of free light chain (FLC) levels. The modern era of MM treatment was ushered in by the introduction of newer chemotherapeutic agents, such as bortezomib. Also, there is interest in the application of extracorporeal removal of FLCs with high cut-off hemodialysis (HCO-HD) using a dialysis membrane with a higher molecular weight cut-off pore size compared to conventional high-flux (HF) dialyzers. Does the use of HCO-HD provide additional benefit to bortezomib-based chemotherapy alone? Two trials have now been completed and the results were published in abstract form and orally presented at the 2016 American Society Nephrology Annual Scientific Meeting in Chicago, Illinois, USA. Both the MYRE and the EuLITE trials randomized patients with dialysis-dependent AKI due to biopsy-confirmed cast nephropathy to bortezomib-based chemotherapy, and either conventional high-flux hemodialysis (HF-HD) or HCO-HD with a primary end point of the discontinuation of renal replacement therapy. In the MYRE study, more patients in the HCO-HD arm were independent of dialysis at 6 months. In the EuLITE study, there was no difference in kidney recovery at 3 months. Both studies were small, which makes any firm conclusions on the benefit of HCO-HD tenuous. Based on the current knowledge, without more robust data, the routine use of HCO-HD cannot be recommended.