Role of adjunct plasma exchange or high cut-off hemodialysis in the management of myeloma cast nephropathy: A systematic review.

Abstract

e20032 Background: Renal impairment by cast nephropathy is a common complication in multiple myeloma. Tubulointerstitial injury results from precipitation of filtered free light chains (FLC) with Uromodulin in the distal convoluted tubules. Rapid reduction in serum FLC levels has shown to improve renal function in modeling studies. Extracorporeal light chain removal techniques such as plasma exchange (PEX) and high cut-off hemodialysis (HCO-HD) have been explored as potential adjunct treatment options for cast nephropathy in various clinical trials. Methods: PubMed, Cochrane library, and Clinicaltrials.gov were searched systematically for the use of plasma exchange and/or hemodialysis with chemotherapy in the treatment of myeloma cast nephropathy using their MeSH words and keywords. PRISMA guidelines were followed for screening and 5 out of 866 studies were finalized (N = 342). Results: Zucchelli et al. 1988 (n = 29) reported a dramatic reduction in Bence Jones protein (BJP) levels of 0.81 ± 0.46 g/day (P value < 0.01) and 1-year survival rate of 66% in the PEX group and decrease in BJP of 3.25 +/- 0.21 g/day (P-value < 0.05) with a survival rate of 28% in the control group. Clark et al. 2005 (n = 104) reported a primary composite response (patient alive at 6 months + dialysis independence + serum creatinine improvement of 50% at 6 months) in 57.9% of patients in the PEX group and 69.2% in the control group [95% CI, -8.3% to 29.1%]; P = 0.36. Johnson et al. 1990 (n = 21) reported a mean change of 880 μmol /L ± 260(SD) in serum creatinine in the PEX group and 570 μmol /L +/-240 in the control group. HD independence at 3 months was reported as 41.3% (n = 19) in the HCO-HD group and 33.3% (n = 16) in the conventional HD group (95% CI -12%–27.9%; P = 0.42) in the MYRE trial 2017 (n = 98). The EuLITE trial 2019 (n = 90) compared the efficacy of the high cut-off vs high flux hemodialysis (HF-HD) technique and concluded that there was no clinical benefit of one over the other. Independence from HD was achieved in 56% (n = 24) in the HCO-HD cohort vs 51% (n = 24) in HF-HD cohort (relative risk [RR] 1.09, 95% CI 0.74–1.61; P = 0.81). Conclusions: The use of high cut-off hemodialysis and plasma exchange as adjunct therapy did not show any significant survival benefit or improvement in clinical outcome. The role of routine use of PEX/HCO-HD in the management of cast nephropathy is still unclear and the decision to use these modalities should be made on an individual basis.