Galactocerebrosidase Reflex, Leukocytes
Use
This test is useful for the diagnosis of Krabbe disease, serving as a confirmatory reflex for the six-enzyme panel. It is utilized for follow-up testing in the evaluation of an abnormal newborn screening result for Krabbe disease. This test is not recommended for carrier detection due to the wide range of enzymatic activities observed in carriers and noncarriers. Reduced or absent galactocerebrosidase activity in leukocytes may indicate a diagnosis of Krabbe disease. However, genetic sequencing of the GALC gene is required to differentiate disease-causing variants from other alterations.
Special Instructions
Not provided.
Limitations
This test was developed and its performance characteristics determined by Mayo Clinic, but it has not been cleared or approved by the FDA. Enzyme levels can appear normal in individuals who have undergone hematopoietic stem cell transplant, and pseudodeficiency of the enzyme is not indicative of disease.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
Galactocerebrosidase
Protein
Result Turnaround Time
4-10 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
6 mL
Minimum Volume
4 mL
Container
Yellow top (ACD solution B preferred, ACD solution A acceptable) or lavender top (EDTA)
Collection Instructions
Send whole blood specimen in original tube. Do not aliquot.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 6 days |
| Refrigerated | 6 days |