J. Pinney

Patients with multiple myeloma have excellent long‐term outcomes after recovery from dialysis‐dependent acute kidney injury

The aim of this study was to report the long‐term outcomes in patients with multiple myeloma (MM) who receive dialysis treatment for acute kidney injury (AKI) due to myeloma cast nephropathy and subsequently recover renal function.

Increased fracture risk in plasma cell dyscrasias is associated with poorer overall survival

Pathological fractures are a common complication of plasma cell dyscrasias (PCD) and are associated with significant morbidity. Routine use of bisphosphonates over the past decade has aimed to reduce the risk of fractures in patients with multiple myeloma, but despite this, fractures continue to represent a significant burden of disease. In this study we report the fracture rate of hospital in‐patients with PCD in England. Data from the national registry Hospital Episode Statistics between 2001 and 2015 were used to determine fracture rate and its effect on overall survival. Fracture rates were 17·8 times higher than the general population in the first year after admission with PCD, and remained elevated for up to 10 years after first admission. The increased fracture risk preceded the first admission with PCD and, conversely, the incidence of PCD increased after admission with one or more fractures. Overall survival is improving with PCD, however poorer survival is found in patients with a preceding fracture (Hazard ratio 1·20). Despite widespread bisphosphonate use, fractures remain common in PCD, and are associated with poorer outcomes.

Multiple myeloma can be accurately diagnosed in acute kidney injury patients using a rapid serum free light chain test

BackgroundAcute kidney injury (AKI) is common in patients with multiple myeloma (MM). Whether serum free light chain (sFLC) measurements can distinguish between myeloma and other causes of AKI requires confirmation to guide early treatment. A rapid and portable sFLC test (Seralite®) is newly available and could reduce delays in obtaining sFLC results and accelerate diagnosis in patients with unexplained AKI. This study evaluated the accuracy of Seralite® to identify MM as the cause of AKI.MethodsFLCs were retrospectively analysed in patients with AKI stage 3 as per KDIGO criteria (i.e. serum creatinine ≥354xa0μmol/L or those on dialysis treatment) (nxa0=xa099); 45/99 patients had a confirmed MM diagnosis.ResultsThe Seralite® κ:λ FLC ratio accurately diagnosed all MM patients in the presence of AKI: a range of 0.14–2.02 returned 100% sensitivity and specificity for identifying all non-myeloma related AKI patients. The sFLC difference (dFLC) also demonstrated high sensitivity (91%) and specificity (100%): an optimal cut-off of 399xa0mg/L distinguished between myeloma and non-myeloma AKI patients. We propose a pathway of patient screening and stratification in unexplained AKI for use of Seralite® in clinical practice, with a κ:λ ratio range of 0.14–2.02 and dFLC 400xa0mg/L as decision points.ConclusionsSeralite® accurately differentiates between AKI due to MM and AKI due to other causes in patients considered at risk of myeloma. This rapid test can sensitively screen for MM in patients with AKI and help inform early treatment intervention.

Successful Renal Outcome in Membranoproliferative Glomerulonephritis Following Treatment of the Underlying Subtle Clone: A Case Report

Membranoproliferative glomerulonephritis (MPGN) secondary to a monoclonal gammopathy is a rare glomerular disease and is defined as a monoclonal gammopathy of renal significance. The disease is characterized by glomerular monotypic immunoglobulin deposits and specific changes on light microscopy and electron microscopy. Immunochemistry is required to establish monoclonality, and electron microscopy helps to characterize the deposits ultrastructurally. Investigation for the underlying monoclonal protein should be done. We report a case of MPGN secondary to monoclonal gammopathy of renal significance that responded to treatment of the underlying clone with chemotherapy, resulting in improvement in renal function. Patients with MPGN and immunoglobulin deposition should be evaluated for a monoclonal protein to guide the management strategy.

Serum free light chain levels and renal function at diagnosis in patients with multiple myeloma

BackgroundRenal impairment (RI) is common in multiple myeloma (MM) and is associated with poor survival. This study reports the associations between renal function and disease characteristics including serum free light chain (FLC) level at diagnosis in patients with MM.MethodsUsing data from the Medical Research Council Myeloma IX trial, a multicentre, randomized, open-label, phase III and factorial-design trial, we assessed the relationships between renal function, demographic, and disease characteristics, including serum FLC levels, in 1595 newly diagnosed MM patients. Multivariable linear regression was utilised to identify factors that were associated with renal function at diagnosis. A receiver operating characteristic curve (ROC) was used to identify the optimal threshold for serum FLC level at diagnosis to predict severe RI.Results52.8% of patients had an estimated glomerular filtration rate (eGFR) ≥60xa0ml/min/1.73xa0m2 (no RI), 37.3% an eGFR 30–59xa0ml/min/1.73xa0m2 (mild to moderate RI), and 9.8% an eGFR <u200930xa0ml/min/1.73xa0m2 (severe RI). In a multivariable analysis, factors independently and negatively associated with eGFR at diagnosis were: higher serum FLC level, female gender, and older age. Elevated serum FLC level at diagnosis, irrespective of the paraprotein type, was strongly associated with severe RI. Receiver operating characteristic curve analysis showed a serum FLC level of >u2009800xa0mg/L as the optimal cut-off associated with severe RI (area under curve 0.86, 95% confidence interval 0.77–0.84).ConclusionThere was a strong relationship between higher serum FLC levels at diagnosis and the severity of RI that was irrespective of the paraprotein type. We report an increased risk of severe RI in patients presenting with serum FLC levels above 800xa0mg/L at diagnosis.