Myeloma kidney, also known as light chain cast nephropathy, is the most common cause of kidney impairment in patients with multiple myeloma. Although it is commonly referred to as myeloma kidney or myeloma cast nephropathy this entity can also occur in patients with Waldenstrom macroglobulinemia and less commonly in CLL. Renal risk from myeloma is very dependent on the burden of circulating monoclonal FLC rather than the amount of M protein spike. Treatment of myeloma with bortezemib is most effective at reducing light chain burden. However, novel therapies with plasmapheresis and high cut-off hemodialysis are currently being studied.