Effective Removal of κ-Free Light Chains with Hemodialysis Using Fresenius Ultraflux® EMiC®2 Dialyser in a Patient with Myeloma Cast Nephropathy, with Associated Cost Savings.

with cyclophosphamide. For AKI due to probable cast nephropathy, HCO HD with Fresenius Ultraflux ® EMiC ® 2 dialyser, 8 h/ session, 5 days/week was commenced. After 2 weeks of treatments, although κ-FLC Dear Editor, Cast nephropathy is the commonest cause of acute kidney injury (AKI) in patients with multiple myeloma (MM) [1] . There has been a recent interest in extended hemodialysis (HD) with high cut-off (HCO) dialysers for removal of immunoglobulinfree light chains (FLC), combined with effective chemotherapy to improve renal and patient outcomes [2, 3] . The conventionally used Gambro HCO 1100 dialyser is expensive. We report a patient with kappa (κ) FLC MM and AKI with significant reductions in κ-FLC levels using the cheaper Fresenius Ultraflux ® EMiC ® 2 dialyser. A 59-year-old Caucasian lady with a background of recurrent MM after autologous bone marrow transplant, treated with lenalidomide, monthly zoledronic acid infusions and later with bortezomib, presented with another relapse and AKI. She had previously had AKI due to biopsy proven cast nephropathy, acute tubular injury and eosinophilic interstitial nephritis secondary to zoledronic acid that was treated with steroids with near complete recovery of renal functions to a serum creatinine of 113 μmol/l. Bortezomib had to be withheld because of disseminated herpes zoster infection, but 4 months later, κ-FLC levels increased from 105 to 11,367 mg/l, with serum creatinine of 393 μmol/l at presentation. Bortezomib was recommenced along Received: March 14, 2016 Accepted: April 14, 2016 Published online: June 8, 2016