Novel Treatments in Improving Renal Outcomes in Light Chain Cast Nephropathy

This study is reviewing real-world outcomes for multiple myeloma patients who developed a serious kidney complication called light chain cast nephropathy — where abnormal proteins from myeloma clog the kidney's filtering tubes. Researchers are comparing patients who were treated with plasma exchange (a process to clean the blood) against those who were not, to see if this treatment improves kidney recovery. **You may be eligible if...** - You are 18 or older - You have been diagnosed with multiple myeloma (new or relapsed) - You developed light chain cast nephropathy with acute kidney injury - You were treated at a participating center in 2010 or later - (For the plasma exchange group) You received at least one round of plasma exchange within 30 days of the kidney diagnosis **You may NOT be eligible if...** - You were treated before 2010 - You do not have a confirmed diagnosis of cast nephropathy with multiple myeloma Talk to your doctor to see if this trial is right for you.