Renal involvement in Refsum's disease.

Renal hemodynamic and tubular functions were measured in a patient with Refsum's disease before and after 12 weeks of twice-weekly plasmaphereses. Percutaneous renal biopsy was performed before initiation of plasmapheresis. These studies were performed to (1) define the nature of the renal lesions and the effects of phytanic acid accumulation on renal functions, and (2) assess the effects of lowering the plasma phytanic acid level on renal functions. The patient, a 39 year old woman, had lipiduria, glycosuria, cylindruria, minimal proteinuria and mild azotemia initially. Renal lesions consist of extensive vacuolization and mitochondrial changes of the tubular epithelial cells, vacuolization of the visceral epithelial cells of the glomeruli, and slight to moderate mesangial sclerosis. The impaired renal hemodynamic function and various tubular functions improved following plasmaphereses associated with reduction of plasma phytanic acid. Over-all clinical improvement was also evident.