Plasma exchange in rapidly progressive renal failure due to multiple myeloma - A retrospective case series

Background/Aims: To evaluate the effect of plasma exchange on renal functio n in patients with rapidly progressive renal failure secondary to multiple myeloma. Methods: The study was done through a retrospective chart review u sing a standardized form at a tertiary care centre in southwestern Ontario. Patients were included in the study if they had a diagnosis of multiple my eloma and rapidly progressive renal failure. Multiple myeloma was defined b y a bone marrow aspirate >15% plasma cells plus one of the following: serum monoclonal paraproteins, monoclonal light-chain excretion, or lytic lesion s. Patients were excluded if they had evidence of chronic renal failure or failed to complete three plasma exchanges. Twenty-six patients were reviewe d; of these 24 were followed up to 1 year. All patients received hydration, standard chemotherapy, and plasma exchange. The plasma exchange volume was 50 ml/kg of 50% normal saline and 50% human serum albumin. Primary outcome measures included (1) prevention of acute dialysis and (2) prevention of p rogression from acute to chronic dialysis; secondary end points included (1 ) a decrease in creatinine of 25% or more within 3 months of the last plasm a exchange and (2) survival at 1 year. Results: Sixteen of 24 patients, fol lowed up to 1 year, did not require dialysis, Two patients required dialysi s initially, but were able to come off dialysis after 3 months. Fourteen pa tients were alive at 1 year, 13 of whom were dialysis independent. Twelve o f 13 dialysis-independent patients had a >25% reduction in creatinine at 3 months. Two patients were lost to follow-up after discharge and were not in cluded in the analysis. Conclusions: This retrospective study suggests that plasma exchange may offer some benefit in preventing the initiation or con tinuation of dialysis in patients with rapidly progressive renal failure se condary to multiple myeloma. A randomized controlled prospective study is n eeded to determine whether plasma exchange should be recommended as a stand ard treatment for patients with rapidly progressive renal failure due to mu ltiple myeloma.