Renal changes in heterozygous Fabry's disease--a family study.

Two sisters, one with a long history of proteinuria and the other of hematuria, came for examination. Physical examination and routine laboratory workups did not show any significant abnormalities. The renal ultrastructural changes in case 1 showed marked enlargement and foamy vacuolation of all the glomerular capillary visceral epithelial cells, which was not found in other glomerular cells. The renal changes in case 2 showed similar lesions but with fewer cells involved and also with less severity, but the involved cells showed marked lamellation within the vacuoles. The serum alpha-galactosidase activity was 4.9 and 3.0 nmol/h/mL serum, respectively (normal values, 12.1 +/- 1.6 nmol/h/mL serum, mean +/- SD, n = 11), thus confirming the heterozygous variety of Fabry's disease. Our findings in these two cases reveal that patients with heterozygous Fabry's disease may present with renal symptoms only, which may be either proteinuria or hematuria.