Kidney Therapy for Free Light Chain Removal in Patients With Multiple Myeloma & Cast Nephropathy

This is an observational study performed to investigate the clinical benefit of FLC removal by KIDNEY therapy system in patients with cast nephropathy, dialysis dependent renal failure and de novo multiple myeloma. Recruitment commenced in July 2014, in total 20 patients will be recruited. Participants will be treated with, KIDNEY therapy system (Bellco Mirandola, Modena, Italy) . The KIDNEY system is a kind of haemodiafiltration that utilizes separated convection, diffusion and adsorption. The sorbent cartridge has a high affinity for FLC (both κ and λ) but is able to re-infuse albumin, avoiding the need for albumin perfusions. The KIDNEY therapy will be undertaken over an intensive treatment schedule. The primary outcome for the study is independence of dialysis in 3 month. Secondary outcomes are: duration dialysis, reduction of serum FLC levels, myeloma response and survival.

Inclusion criteria

• Age >= 18 years
• Dialysis dependent acute renal failure
• Fulfils diagnostic criteria for the diagnosis of symptomatic de novo multiple myeloma
• Abnormal serum FLC ratio and a sFLC concentration > 500 mg/L
• Myeloma kidney demonstrated on a renal biopsy (cast nephropathy)
• Ability to give informed consent to partake in study
• Commencement of study within 10 days of presenting to enrolling unit

Exclusion criteria

• Known advanced chronic renal failure (CKD stage IV 4-5; eGFR <30mls/min/1.73m2) or evidence of significant chronic damage on renal biopsy
• Amyloidosis or light chain deposition disease on renal biopsy
• Previous treatment of multiple myeloma with chemotherapy
• Haemodynamic instability that precludes unsupported dialysis renal replacement therapy
• Significant cardiac disease
• Active uncontrolled infection
• Inability to give informed consent