Test Code GALCW Galactocerebrosidase, Leukocytes
Reporting Name
Galactocerebrosidase, WBCPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Diagnosis of Krabbe disease
Follow-up testing for evaluation of an abnormal newborn screening result for Krabbe disease
This test is not intended for carrier detection.
Method Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Ordering Guidance
This test will not detect carrier status. For differentiating alterations from disease-causing variants in affected patients and for carrier detection in family members, molecular sequencing of the GALC gene is necessary. Order KRABZ / Krabbe Disease, Full Gene Analysis and Large (30 kb) Deletion, Varies.
Shipping Instructions
For optimal isolation of leukocytes, it is recommended the specimen arrive refrigerate within 6 days of collection to be stabilized. Collect specimen Monday through Thursday only and not the day before a holiday. Specimen should be collected and packaged as close to shipping time as possible.
Specimen Required
Container/Tube:
Preferred: Yellow top (ACD solution B)
Acceptable: Yellow top (ACD solution A) or lavender top (EDTA)
Specimen Volume: 6 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Specimen Type
Whole Blood ACDSpecimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood ACD | Refrigerated (preferred) | 6 days | |
Ambient | 6 days |
Reject Due To
Gross hemolysis | Reject |
Reference Values
≥0.300 nmol/hour/mg protein
An interpretative report will be provided.
Interpretation
When abnormal results are detected, a detailed interpretation is given, including an overview of the results and of their significance, a correlation to available clinical information, elements of differential diagnosis, recommendations for additional biochemical testing, and in vitro, confirmatory studies (enzyme assay, molecular analysis), name and phone number of key contacts who may provide these studies, and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.
Day(s) Performed
Preanalytical processing: Monday through Saturday
Testing performed: Monday, Wednesday
Report Available
5 to 9 daysTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82657
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
GALCW | Galactocerebrosidase, WBC | 24084-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
606270 | Galactocerebrosidase, WBC | 24084-6 |
606271 | Interpretation | 59462-2 |
606272 | Reviewed By | 18771-6 |
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Biochemical Genetics Patient Information (T602)
3. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
Testing Algorithm
If the patient has abnormal newborn screening result for Krabbe disease, immediate action should be taken. Refer to the appropriate American College of Medical Genetics and Genomics Newborn Screening ACT Sheet.(1,2)
The following information is available:
-Newborn Screen Follow-up for Krabbe Disease: Galactocerebrosidase
-Newborn Screen Follow-up for Krabbe Disease: Galactocerebrosidase and Psychosine