ALPHA-L-IDURONIDASE, LEUKOCYTES - (B)

Test Code: MIS8

Test Indications: Diagnosis of mucopolysaccharidosis I, Hurler, Scheie and Hurler-Scheie syndromes in leukocytes.
 
This test is second tier testing following a positive result to urine mucopolysaccharides fractionnation with an elevation of dermatan sulfate and heparan sulfate which is suggestive of MPS type I. This test may also be performed based on strong clinical suspicion of MPS I.
 
This test is not useful for determining carrier status.
 
THIS TEST MUST BE APPROVED by the Biochemical Geneticist prior to being ordered, and must be coordinated with the Metabolic Laboratory. (Biochemistry Approval for Test Referral)
 
This test is time sensitive.
 
Methodology: Flow Injection Analysis -Tandem Mass Spectrometry (FIA-MS/MS) by Mayo Clinic Laboratories
 
Cautions: The presence of a pseudodeficiency allele may cause reduced activity of alpha-L-iduronidase in the artificial subtrate used in this assay. This can result in values below the normal reference range but will typically be greater than levels found in individuals with mucopolysaccharidosis I (MPS I).
 
This test does not differentiate between Hurler and Scheie syndromes.
 
Enzyme levels may be normal in individuals receiving enzyme replacement therapy or who have undergone hematopoietic stem cell transplant.
 
For questions/information: Call Metabolic Lab at 204-787-4530 and ask for the Biochemical Geneticist.  

Lavender top (EDTA) is also acceptable.

_SH Biochemical Genetics Laboratory Requisition (R250-10-69)

An interpretive report will be provided.

If you have any questions, please communicate with the Metabolic Lab (HSC): 204-787-4530
 
Reject due to: Gross hemolysis.
 
Stability:
Ambient  -  72 hours
Refrigerated  -  4 days
 
Send to Mayo refrigerated, same day of collection
MAYO ID: IDUAW
CPT code: 82657