Fabry Nephropathy.

Fabry disease is a rare X-linked recessive lysosomal storage disease. Multiple mutations of the GLA gene lead to a deficient or absent activity of the lysosomal enzyme α-galactosidase A, resulting in progressive glycotriaosylceramide accumulation in many organs. Low α-galactosidase A activity and mutations in the GLA gene confirm the diagnosis. Clinical signs are multisystemic, heterogeneous, and progressive. Renal, cardiac, and neurovascular involvements are the main life-threatening complications, highlighting the importance of an early initiation of enzyme replacement therapy improving long-term outcome. Fabry nephropathy lesions are characterized by a cell vacuolization of glomeruli, tubules, interstitium, and arteries and by ultrastructural myelin bodies. The main histologic differential diagnoses are toxicity of lysosomal inhibitors and other renal lipidoses. Renal biopsies are not necessary for diagnosis but have an important role in the evaluation of disease evolution and treatment efficiency, which is a major challenge for improving outcome and quality of life.