Beta-mannosidosis : Beta-mannosidase Enzyme Analysis

Test Information

This biochemical test is a quantitative measurement of beta-mannosidase enzyme activity can be used as a 1st tier test for patients with a clinical suspicion of beta-mannosidosis. Demonstration of deficient beta-mannosidase enzyme activity is considered the gold standard to confirm a diagnosis of beta-mannosidosis.

Turnaround Time

14 days

CPT Code(s)

82657

Cost

$200


Enzymes

Beta-mannosidase

Clinical Information

Beta-mannosidosis is one of the glycoproteinosis disorders, a subcategory of very rare lysosomal storage diseases. Patients with beta-mannosidosis typically have some degree of developmental delay or intellectual disability. Most of these patients have mild or no dysmorphic features. Behavior abnormalities, angiokeratomas, seizures, demyelinating peripheral neuropathy, and deafness have all been reported in association with beta-mannosidosis.

Indications

This test can be used to confirm a suspected Beta-mannosidosis syndrome diagnosis.

Methodology

Quantifies level of beta-mannosidase via the 4-methylumbelliferyl substrate.

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.

Transport Instructions

Whole blood samples (for leukocyte analysis) should be shipped at ambient temperature and must arrive at the laboratory within 24 hours of blood draw. Cultured fibroblasts can 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. Ship at ambient temperature.

Have Questions Need Support?

Call our laboratory at 1-800-473-9411 or contact one of our Laboratory Genetic Counselors for assistance.
Robin Fletcher, MS, CGC
Kellie Walden, MS, CGC

Biochemical Testing, Enzyme Analysis, Individual Enzyme Assays
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