Presentation and survival of patients with severe acute kidney injury and multiple myeloma: a 20-year experience from a single centre.

Background. Myeloma is the second most common haematological malignancy and is a cause of severe acute kidney injury (serum creatinine ≥500 μmol/L) that has long been associated with a poor prognosis, although previous series have been small. Methods. We have therefore documented the natural history of all 107 patients referred to a large regional renal unit over a 20-year period and investigated factors associated with survival over a long period of time using Cox regression methods. Results. Three factors were found to be significantly and independently associated with survival: use of chemotherapy [hazard ratio (HR) 0.21, 95% CI: 0.08―0.46, P < 0.001], serum albumin (HR 0.49, 95% CI: 0.29―0.82, P = 0.02 for ≥35 g/L versus <35 g/L) and dialysis independence (HR 0.43, 95% CI: 0.24―0.76, P = 0.005). However, survival was not found to be better for patients presenting in the second decade compared to the first (HR 0.88, 95% CI: 0.52―1.50, P = 0.65). Conclusions. This analysis highlights the need for clinical trials of novel chemotherapy regimens in this complicated group of patients. Furthermore, whether strategies to restore or preserve dialysis-independent renal function provide additional benefit to effective chemotherapy also requires further investigation. The advent of efficacious low toxicity chemotherapy (such as thalidomide and bortezomib) and new dialysis techniques to remove free light chains may radically alter the outcome of this group of patients.