alpha-N-acetylgalactosaminidase
Schindler/Kanzaki Disease: Alpha-N-Acetylgalactosaminidase Enzyme Analysis
Key Information
Lab:
TAT:
14 days
Price:
$200
CPT Code(s):
82657
Test Code:
BSCHP, BSCHL, BSCHD
Schindler/Kanzaki Disease: Alpha-N-Acetylgalactosaminidase Enzyme Analysis
This test quantitatively measures alpha-N-acetylgalactosaminidase enzyme activity and can be used as a first-tier test for patients with a clinical suspicion of Schindler/Kanzaki disease. Confirming deficient enzyme activity is the gold standard in diagnosis and can be used to support the interpretation of variants and monitor patients.
Schindler disease (Kanzaki disease)
Clinical Information
Schindler disease is a rare, autosomal recessive lysosomal storage disorder characterized by varying degrees of neurologic impairment. In the infantile form of Schindler disease (Type I), developmental regression becomes evident around the age of one in a previously healthy child. In addition to this rapid progression of intellectual disability, affected children develop optic atrophy leading to vision loss, spasticity, and seizures. Muscle atrophy and contractures may occur, and patients generally become unresponsive to their surroundings. Most affected individuals die in early childhood. Type II Schindler, also known as Kanzaki disease, is an adult-onset disorder associated with muscle weakness, hearing loss, mild intellectual changes, and angiokeratomas. An intermediate type may exist, and its features include developmental delays, seizures, cardiomyopathy, hepatomegaly, and behavioral changes.
Technical Information
4-methylumbelliferyl (4-MU) substrate
Specimen Requirements
DBS: Approximately 75 uL of blood should be applied to each of the five circles on filter paper dried blood spot card. Allow blood to dry for at least 4 hours before shipping.
Leukocytes: Minimum of 5 mL whole blood (7-10 mL preferred) collected in a sodium heparin tube
Plasma: A minimum of 3 mL whole blood collected in a sodium heparin tube; or blood can be centrifuged and a minimum of 1 mL plasma removed and sent for analysis.
Transport Instructions
DBS: Ship DBS card at ambient temperature.
Fibroblasts: Ship tissue sample or cultured fibroblasts at ambient temperature
Leukocytes: Whole blood should be shipped at ambient temperature. If leukocytes are being isolated at another laboratory, the pellet should be frozen after specimen processing and shipped frozen on dry ice.
Plasma: Plasma should be frozen after collection and shipped frozen, preferably on dry ice. Whole blood should be shipped at ambient temperature.
Connect With Our Experts
Call 1-800-473-9411 to speak with our team of laboratory genetic counselors for questions or additional information.
Robin Fletcher, MS, CGC
Falecia Thomas, MS, CGC
Alex Finley, MS, CGC