Subclinical Fabry's disease occurring in the context of IgA nephropathy.

A 28-year-old male patient with both IgA nephropathy and an unusual case of Fabry's disease has been followed for 10 years. Diagnosis of both these diseases was made by histological examination of renal biopsy tissues and the enzyme activities of alpha-galactosidase A. Serial biopsies revealed the hithertofore unrecognized process of glomerular glycolipid accumulation peculiar to Fabry's disease at the initial stages of the disease. Physical examinations and routine laboratory analyses failed to show significant signs of Fabry's disease throughout the 10-year period. While alpha-galactosidase A activity is markedly decreased in the plasma of this patient as in classical Fabry hemizygotes, the activity in leukocytes and culture fibroblasts showed a considerable residual activity. Fabry's disease associated with IgA nephropathy apparently is extremely rare, and the present subclinical case is unique in that the early stages of substrate accumulation are demonstrable.