Galactosemia Reflex, Blood
Use
This test is preferred for the diagnosis, carrier detection, and determination of genotype for galactose-1-phosphate uridyltransferase deficiency, the most common cause of galactosemia. It helps differentiate Duarte variant galactosemia from classic galactosemia and confirms results of newborn screening programs. It is routinely used for evaluating possible diagnosis of galactosemia, carrier screening, and follow-up of abnormal newborn screening results.
Special Instructions
Not provided.
Limitations
This assay will not reliably detect deletions-insertions of 40 or more base pairs, including Alu insertions and other repetitive elements. Low-level mosaic variants may not be identified accurately. Additionally, it is not designed to distinguish between somatic and germline variants, potentially requiring additional testing. The interpretation of test results should account for clinical findings, family history, and other lab data to minimize errors.
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 24082-0 - Gal1PUT RBC-cCnt
- 24082-0 - Gal1PUT RBC-cCnt
- 59462-2 - Clinical biochemist review
- 18771-6 - Provider signing name
Result Turnaround Time
4-7 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
5 mL
Minimum Volume
2 mL
Container
Lavender top (EDTA); Green top (sodium heparin) or yellow top (ACD) acceptable
Collection Instructions
Invert several times to mix blood. Send whole blood specimen in original tube. Do not aliquot.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 28 days |
