--- Query Results ---

  
Program:Genetics and Genomics
 
Test Name:S-Adenosylmethionine and S-Adenosylhomocysteine (G&G South ACH)
Test Code:SAM-P
Performing Site: Alberta Children's Hospital
Performing Dept:Biochemical Genetics
 
Availability:Test is performed on a monthly basis.
TAT:45 days
 
Preferred Tube/Container:K2 EDTA - Plastic tube (royal blue top)
 
Specimen Requirements:1. Collect 1 x 4.0 mL K2 EDTA tube.
2. Collect following a minimum four-hour fast; or just before next feed for newborns.
3. Indicate length of fast, or time of last feeding on the requisition (with collection time).
 
Min. Sample Required:1.0 mL whole blood
 
Specimen Processing:Place sample immediately on ice.
 
Specimen Handling:Transport immediately to ACH Biochemical Genetics Laboratory or immediately call ACH Biochemical Genetics Laboratory (403-955-7379) for sample pick-up.
 
Additional Information:Should collection be required at a site other than ACH, contact the ACH Biochemical Genetics Lab (403-955-7379) PRIOR TO sample collection for instructions on how to properly handle the sample.
 
Requisition/Form:Submit request using Biochemical Genetics Laboratory Requisition.
Please ensure all required information, including patient's clinical history/indication, is provided on the requisition.
 
Order Restrictions:This test is considered specialty testing; this test will be cancelled if sufficient clinical justification is not provided.
 
Indications:This test is for the further investigation in a patient with hypermethioninemia and/or homocystinuria to distinguish between several disorders affecting methionine metabolism and the methylation cycle.
Method:S-adenosylmethionine and S-adenosylhomocysteine are detected using liquid chromatography, electrospray-ionization tandem mass spectrometry (LS-MS/MS) with a deuterium-labelled internal standard.
Method Details:S-adenosylmethionine and S-adenosylhomocysteine can be abnormal in the following enzyme deficiencies / disorders:

Disorders with elevated S-adenosylmethionine and S-adenosylhomocysteine
  • cystathionine beta-synthase deficiency (classical homocystinuria)
  • S-adenosylhomocysteine hydrolase (SAHH) deficiency
  • adenosine kinase (ADK) deficiency

    Disorders with elevated S-adenosylmethionine Only
  • glycine N-methyltransferase (GNMT) deficiency
  • mtDNA depletion syndrome

    Disorders with Low-Normal S-adenosylmethionine
  • methionine adenosyltransferase (MAT) I/III deficiency
  • methylenetetrahydrofolate reductase deficiency (MTHFR)
  • methionine synthase deficiency
  • Cobalamin (Cbl) C, D, E, F, G, J and X deficiencies
  • transcobalamin II deficiency
  • severe folate or B12 deficiencies

    Other causes of Elevated S-adenosylmethionine and S-adenosylhomocysteine
  • chronic kidney disease
  •  
    Reference Interval:
    S-Adenosylmethionine (SAM)            86-132  nmol/l
    S-Adenosylhomocysteine (SAH)              9-29  nmol/l
    Total (SAM + SAH)          102-161  nmol/l
     
    Comments:Contact ACH Biochemical Genetics Laboratory (403-955-7379) for priority turn-around.
     
     
    Last Updated On:Friday, August 18, 2017
    Date of Last Review:Jan 2 2018 12:00AM