Controlled plasma exchange trial in acute renal failure due to multiple myeloma

Controlled plasma exchange trial in acute renal failure due to multiple myeloma. We studied 29 patients affected by acute renal failure due to multiple myeloma with Bence-Jones proteinuria > 1 g/day to evaluate the effectiveness of plasma exchange in the treatment of severe myeloma nephropathy. Renal failure was severe enough to require dialysis in 24 cases, while the remaining 5 patients showed serum creatinine levels greater than 5 mg/dl. The patients were randomly allocated to Group I (15 patients undergoing plasma exchange together with corticosteroids, cytotoxic drug, hemodialysis only when needed) or to Group II (14 patients undergoing peritoneal dialysis together with corticosteroids and cytotoxic drug). In Group I Bence-Jones proteinuria decreased dramatically (P < 0.01) with a significant increase in urine output (P < 0.001), while Group II presented a slight reduction in Bence-Jones proteinuria without a significant increase in daily diuresis. Thirteen out the 15 Group 1 patients recovered renal function reaching serum creatinine levels < 2.5 mg/dl in most cases. Only two patients in Group II improved renal failure well enough to stop dialysis. The one-year survival rate was significantly higher in Group I (66%) than in Group II (28%, P < 0.01). We conclude that plasma exchange associated to chemotherapy rapidly removes large amounts of light chains, improves both renal function and long-term survival expectancies.