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Alpha-Iduronidase, Dried Blood Spot - Saskatoon

Discipline

Biochemistry

Overview

Description

  • ​All required information on the consent form must be filled out:
    • Physician must sign confirmation of informed and medical necessity for genetic testing.
    • Patient must sign the consent before blood collection.
    • Please note that an incomplete form will result in cancellation of the test.
  • This is a quantitative enzyme activity test. Alpha-iduronidase activity is measured using dried blood spot.
  • This biochemical test can be used as a 1st tier test for patients with a clinical suspicion of Mucopolysaccharidosis type I (MPS I).

Alias

  • ​Hurler Syndrome
  • Scheie Syndrome (MPS 1)

Specimen Information

Specimen types accepted

  • ​Whole blood
  • Dried blood spots will be made when whole blood received in the lab

Specimen collection container

Required volume

  • Optimal volume: 4 mL whole blood
  • Minimum/pediatric volume: 1 mL whole blood

Transport and stability

  • ​Whole blood must be received within 24 hours of collection
  • Store whole blood at room temperature
  • Lysosomal Storage Disorder Card should be spotted with whole blood within 24 hours of collection
  • Once spotted, the Lysosomal Storage Disorder Card should be stored at -20°C or below if held for greater than 48 hours

Rejection criteria

Testing Information

Relevant clinical history

  • ​Family history
  • Must include diagnosis and/or patient symptoms on the requisition

Clinical interpretation

  • Result interpretation should be correlated with clinical findings, patient history and other laboratory findings

Performance

Methodology

  • Tandem mass spectrometry

Days/times performed

  • Testing site - Referred out by St. Paul’s Hospital Laboratory PerkinElmer, Pittsburgh, PA

Maximum laboratory time

  • 3 week turnaround time by referral laboratory

Other information

​Additional comments
  • Mucopolysaccharidosis type I (MPS-I) is a chronic, progressive lysosomal storage disorder caused by alpha-iduronidase deficiency.
  • Based on the severity of disease, MPS-I can be classified into 3 subclasses: Hurler syndrome, Hurler-Scheie syndrome and Scheie syndrome.
  • Alpha-Iduronidase deficiency results in an accumulation of DS and HS in the lysosome, affecting bones, cartilage and brain. Glycosaminoglycans (GAGs) can be easily identified in urine. Generally, patients with MPS disorders usually have high excretion of urine GAGs. 
Forms required

Last Updated: August 7, 2025