Incidence of Kidney Replacement Therapy and Subsequent Outcomes Among Patients With Systemic Lupus Erythematosus: Findings From the ERA Registry.

RATIONALE & OBJECTIVE: There is a dearth of data characterizing patients receiving kidney replacement therapy (KRT) for kidney failure due to systemic lupus erythematosus (SLE) and their clinical outcomes. The aim of this study was to describe trends in incidence and prevalence of KRT among these patients as well as to compare their outcomes versus those of patients treated with KRT for diseases other than SLE. STUDY DESIGN: Retrospective cohort study based on kidney registry data. SETTING & PARTICIPANTS: Patients recorded in 14 registries of patients receiving KRT that provided data to the European Renal Association Registry between 1992 and 2016. PREDICTOR: SLE as cause of kidney failure. OUTCOMES: Incidence and prevalence of KRT, patient survival while receiving KRT, patient and graft survival after kidney transplant, and specific causes of death. ANALYTICAL APPROACH: Kaplan-Meier methods and Cox regression models were fit to compare patient survival between the SLE and non-SLE groups, overall KRT, dialysis, and patient and graft survival after kidney transplant. RESULTS: In total, 1,826 patients commenced KRT for kidney failure due to SLE, representing an incidence of 0.80 per million population (pmp) per year. The incidence remained stable during the study period (annual percent change, 0.1% [95% CI, -0.6% to 0.8%]). Patient survival among patients with SLE receiving KRT was similar to survival in the comparator group (hazard ratio [HR], 1.11 [95% CI, 0.99-1.23]). After kidney transplant, the risk of death was greater among patients with SLE than among patients in the comparator group (HR, 1.25 [95% CI, 1.02-1.53]), whereas the risk of all-cause graft failure was similar (HR, 1.09 [95% CI, 0.95-1.27]). Ten-year patient overall survival during KRT and patient and graft survival after kidney transplant improved over the study period (HRs of 0.71 [95% CI, 0.56-0.91], 0.43 [95% CI, 0.27-0.69], and 0.60 [95% CI, 0.43-0.84], respectively). Patients with SLE receiving KRT were significantly more likely to die of infections (24.8%) than patients in the comparator group (16.9%; P < 0.001). LIMITATIONS: No data were available on extrarenal manifestations of SLE, drug treatments, comorbidities, kidney transplant characteristics, or relapses of SLE. CONCLUSIONS: The prognosis of patients with SLE receiving KRT has improved over time. Survival of patients with SLE who required KRT was similar compared with patients who required KRT for other causes of kidney failure. Survival following kidney transplants was worse among patients with SLE.

Haemodialysis using high cut-off dialysers for treating acute renal failure in multiple myeloma.

INTRODUCTION: Acute renal failure (ARF) occurs in 12%-20% of all multiple myeloma (MM) cases, and the survival of these patients depends on renal function recovery. Renal function is not recovered in 75% of dialysis-dependent patients, and their mean survival with replacement therapy is less than one year. Renal tubular disease is the most frequent cause of renal failure. It is present in more than 55% of renal failure cases and in 75% of those requiring dialysis. Rapid reduction of free light chain levels in the blood is necessary in order to recover renal function. One coadjuvant measure in treating the disease is reducing light chain levels with plasmapheresis, but its efficacy has not yet been clearly proven. Our proposal was therefore to use extended haemodialysis sessions with high cut-off dialysers (HCO-HD), obtaining a recovery rate of more than 60%. We present the progress of 6 patients with myeloma and acute renal failure who were treated with HCO-HD and the complications associated with using this type of haemodialysis. Then, we review the pros and cons of this technique. METHOD: Six patients diagnosed with MM and ARF requiring dialysis and with serum free light chain levels above 500 mg/l were treated with 8-hour haemodialysis sessions with an HCO-HD filter. Before and after each session, serum free light chain levels were measured by nephelometry; other parameters were recorded as well. At the same time, patients underwent chemotherapy according to protocols. RESULTS: The symptom onset times of the 3 men and 3 women diagnosed with MM and ARF were highly variable, from 7 days to more than 1 year. We performed 90 extended sessions with HCO-HD filters, and each patient underwent between 6 and 40 sessions. Free light chain levels decreased by a mean of 65% between treatment onset and completion, except in one patient who experienced a 12.6% reduction. The mean percentage of reduction of light chain levels per session was 54.98% ± 17.27%. A complication occurred during 28% of the sessions. Of these complications, 48% were due to system coagulation. There were no major changes in pre-dialysis albumin, calcium, phosphorous or magnesium levels, although lower values that were not clinically relevant were recorded in one case. Renal function was recovered in 3 patients, they are alive and dialysis-free. In biopsied cases that recovered renal function, the specimen showed tubular nephropathy only. Those patients who took longer to be diagnosed did not recover their renal function, and when biopsied, they were diagnosed with renal tubular disease and light chain deposition disease. CONCLUSION: We found extended haemodialysis with HCO-HD filters to be a reasonable alternative in ARF caused by renal tubular disease, and achieved a recovery rate of 50% in our cases. Function recovery was influenced by the elapsed time between symptom onset and myeloma diagnosis, histological findings, promptness of starting chemotherapy, response to chemotherapy, and effectiveness of light chain extraction. In any case, further studies are needed to examine new chemotherapy agents and new direct free light chain removal techniques.