NEW YORK (Reuters Health) – Use of a high cut-off dialyzer can help patients with acute renal failure secondary to multiple myeloma become dialysis free, the results of a small study suggest.
“This study saw over 70% of patients becoming independent of dialysis, which is greatly above the rate expected in this setting,” lead author Dr. Colin A. Hutchison, from Queen Elizabeth Hospital, Birmingham, UK, said in a statement. “High cut-off hemodialysis is exciting because it offers a novel way of treating this group of patients who have historically done very poorly.”
Free light chains, as a byproduct of immunoglobulin synthesis, are usually cleared rapidly by the kidney, but clonal proliferation in multiple myeloma can lead to very high concentration of monoclonal free light chains. This can lead to cast nephropathy, the researchers explain in the April issue of the Clinical Journal of the American Society of Nephrology.
Prior research has shown that high cut-off hemodialysis can remove large amounts of free light chains in multiple myeloma patients, according to the report. Whether this actually improves clinical outcomes, however, was unclear.
The new study involved 19 patients who were treated with standard chemotherapy and received high cut-off hemodialysis.
An early and sustained reduction in free light chain levels (median 85%) was seen in 13 patients, all of whom became dialysis independent at median of 27 days.
The six other patients had chemotherapy interrupted due to infections and did not have sustained reductions in free light chain levels. Only one of the six recovered their renal function.
Renal function recovery was a significant predictor of improved survival, the authors note. They add that a randomized trial is now underway to confirm these findings.
Clin J Am Soc Nephrol 2009;4:745-754.