Regression of renal amyloid deposits by VAD therapy plus autologous stem cell transplantation in a patient with primary AL amyloidosis

We report a 58-year-old Japanese woman who presented with nephrotic syndrome. Steroid therapy and cyclosporine A administration were initiated, but hematological remission and renal response were not achieved. Renal biopsy revealed amyloid deposits in the mesangial region and the small arteries. Proteomic analysis based on laser microdissection and mass spectrometry showed that the amyloid deposits were composed of the constant region of the lambda light chain. She received vincristine, adriamycin, and dexamethasone therapy followed by high-dose melphalan and autologous stem cell transplantation, resulting in hematological complete remission and renal response with negative urinary Bence-Jones protein and proteinuria. Renal biopsy was performed four times during follow-up, demonstrating that amyloid deposits decreased gradually, while glomeruli showing global sclerosis increased from 3 to 62%. This case suggests that glomerular amyloid deposits can be cleared via tissue remodeling, if stem cells producing amyloid precursors are completely replaced by unrelated cells after stem cell transplantation.