Background: The study assessed dialysis support in patients with primary systemic amyloidosis without associated multiple myeloma in whom renal insufficiency developed.
Methods: The study group consisted of 211 patients with biopsy-proved primary systemic amyloidosis examined at the Mayo Clinic, Rochester, Minn. No patient was lost to follow-up.
Results: Thirty-seven (18%) of the patients received dialysis therapy. Of those presenting with renal amyloid, one third received dialysis. The median time from diagnosis to initiation of dialysis was 13.8 months. The median survival for patients from the start of dialysis was 8.2 months. There was no survival difference between hemodialysis (n = 27) and peritoneal dialysis (n = 10). The most important predictors of which patients would ultimately require dialysis were the 24-hour urinary protein loss and serum creatinine values at the time amyloidosis was diagnosed. None of the patients seen at diagnosis with a normal serum creatinine value and proteinuria of less than 2 g/d required dialysis during follow-up. Of the 37 patients who received dialysis, 31 died, and 21 of the 31 died as a result of extrarenal progression of their systemic amyloidosis. Fifteen of the 31 deaths were a result of cardiac amyloidosis. All long-term survivors had normal echocardiograms without evidence of amyloid.
Conclusion: Eighteen percent of patients with primary amyloidosis undergo dialysis. The 24-hour urinary protein loss and creatinine values are helpful in predicting which patients eventually will require dialysis. The median survival for patients starting dialysis is less than 1 year. Patients whose two-dimensional echocardiograms are normal are most likely to derive long-term benefit from dialysis.