MO670EXPANDED HEMODIALYSIS REDUCES THE CONCENTRATION OF FREE LIGHT CHAINS IN PATIENTS WITH ACUTE KIDNEY INJURY IN MYELOMA CAST NEPHROPATHY

Abstract

\n \n \n The myeloma cast nephropathy is largely associated with the production of intact immunoglobulin and free light chains (FLC) by a plasma cells monoclone. The use of high-flux hemodiafiltration (HDF) contributes to a decrease in the concentration of FLC. However, it is not always possible to achieve the required substitute volume with acute kidney injury (AKI) emergency treatment. An alternative to HDF could be the usage of membranes with a medium cut-off (expanded hemodialysis (HD), Expanded HD). The aim of this study was to compare the degree of reduction in FLC concentration using conventional HD, HDF and Expanded HD.\n \n \n \n The study includes patients with newly diagnosed multiple myeloma who presented indications for HD therapy start. Procedures were performed on a daily basis from the moment when indications for HD therapy were identified. The duration of the first three procedures was 2 hours. Consistently for each patient the first procedure was carried out using a standard low-flow filter, the second - using a high-flow dialyzer and HDF (substitute volume 9 liters for 2 hours), the third - using a Theranova 400 filter (Baxter, Germany). The concentrations of FLC (kappa and lambda) and albumin were determined every 30 minutes of each treatment. Chemotherapy was prescribed according to the local clinical recommendations in combination with the ongoing renal replacement therapy.\n \n \n \n The study included 7 patients with cast nephropathy, mean age 68±8 years. Average concentration before treatment: kappa FLC 876±727 μg/ml (norm 3.25-15.81 μg/ml), lambda FLK 84±112 μg/ml (norm 3.23-28.05 μg/ml), albumin 34±1 g/l (norm 40-50 g/l). After 2 hours of treatment, there was a decrease in kappa FLC concentration with HDF (-34±33%, p=0.01) and with Expanded HD (-31±12%, p<0.001), but not with conventional HD (-1±7, p=0.79, Fig 1). The lambda FLC concentration also decreased with HDF (-41±29%, p=0.01) and with Expanded HD (-28±22%, p=0.01), but not with conventional HD (-3±12, p=0.65, Fig 2). Albumin concentrations did not change significantly with any of the treatments.\n \n \n \n Expanded HD, as well as high-flow HDF, helps to reduce the FLC concentration in patients with cast nephropathy without loss of albumin, which may have a positive effect on the multiple myeloma prognosis. Further studies are needed regarding possibilities of using Expanded HD in the complex therapy for patients with AKI in myeloma cast nephropathy.\n