Metachromatic Leukodystrophy – Enzyme Analysis

Disease name Metachromatic leukodystrophy
Enzyme Name Arylsulfatase A
Clinical info Metachromatic leukodystrophy is an autosomal recessive condition caused by a deficiency of arylsulfatase A, an enzyme crucial to the breakdown of sulfatides in the body. Metachromatic leukodystrophy should be considered in any individual with progressive neurological dysfunction and MRI evidence of a leukodystrophy. This condition can present as late-infantile, juvenile or adult forms.
Indications Patients with a suspected diagnosis of metachromatic leukodystrophy through clinical symptoms and MRI findings. Prenatal diagnosis and carrier testing via enzyme analysis are not available.
Methodology Measurement of enzyme activity via spectrophotomer
Specimen Requirements Enzyme activity can be measured in leukocytes, cultured fibroblasts, or dried blood spots. For leukocytes, please send 5-10 ml of whole blood in a green top (sodium heparin) tube. For dried blood spot collection, a minimum of three circles need to be filled in. Each circle should contain one drop of blood (about 100 microliters). See the link below for additional sample collection and handling instructions.

Sample Collection and Requirements

In addition, a dried blood spot or blood drawn in an EDTA tube can be used for Arylsulfatase A molecular analysis and may be sent for DNA banking. Please indicate on the requisition if DNA should be banked for follow-up molecular testing.


Whole blood samples (for leukocyte analysis) should be shipped at ambient temperature and must arrive at the laboratory within 24 hours of specimen collection.

Cultured fibroblasts should be sent overnight at room temperature.   

For a dried blood spot: When the sample has dried 3-4 hours, fold cover at score line, over sample, and tuck into flap. Samples should be placed in the mail within 24 hours of collection. Overnight shipping is preferred.

Turnaround time 14 days
Cell culture can take 1-4 weeks and may lengthen turnaround time.
CPT Codes 82657
Cost Leukocytes or cultured fibroblasts: $200

Dried Blood Spot Analysis: A 50% discount will be applied for enzyme analysis from a dried blood spot reducing the price to $100.

Contact For further information contact one of our This email address is being protected from spambots. You need JavaScript enabled to view it. at 1-800-473-9411.

Biochemical Lab

The Biochemical Lab provides diagnostic and screening tests for a variety of inherited metabolic disorders.

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