α-Galactosidase A (Fabry Disease)
Fabry disease is an X-linked condition caused by a deficiency of alpha-galactosidase A enzyme activity. Affected individuals are unable to degrade globotriaosylceramide (GL-3) in their lysosomes. The progressive accumulation of GL-3 results in symptoms that include characteristic skin rashes (angiokeratomas), decreased sweating (hypohidrosis), chronic fatigue, depression, neuropathic pain in the hands and feet (acroparesthesia), gastrointestinal issues, strokes, cardiac disease (including left ventricular hypertrophy), and renal disease (proteinuria to end stage renal disease). Fabry disease affects both men (hemizygotes) and women (heterozygotes), but testing strategy varies based on gender. Alpha galactosidase A enzyme analysis alone should detect all affected males and may also detect ~60% of heterozygote females affected by Fabry disease. In order to increase the detection of females with Fabry disease, combined enzyme analysis with sequencing of the alpha galactosidase A gene is recommended. Flurometric enzyme analysis using artificial substrate 4-methylumbelliferyl-a-galactopyranoside is used to measure a-glucosidase activity. Both plasma and leukocyte enzyme activity are measured in this assay.
Two 5-10 ml sodium heparin (green top) tubes of blood.
Ship whole blood at room temperature. Blood samples must be received within 48 hrs of collection. If the sample cannot be sent immediately, prepare and freeze plasma and leukocyte pellets until shipment and ship frozen on dry ice.
Turnaround Time: 7-10 days
CPT Codes: 80500, 82657x2, 84155
Consent Form: Fabry Consent Form [PDF]
Requisition Form: Fabry Testing Requisition and Information [PDF]
Related Tests: Fabry Disease (DNA)