Pyridoxal 5-Phosphate, Plasma
Use
Determining vitamin B6 status, including in persons with progressive nerve compression disorders such as carpal tunnel and tarsal tunnel syndromes. Evaluates the success of a vitamin B6 supplementation program and assists in the diagnosis and evaluation of hypophosphatasia. Vitamin B6, including pyridoxal 5-phosphate (PLP), is crucial for over 140 enzyme reactions and is a possible factor in nerve compression disorders and other symptoms like burning mouth syndrome, scaling skin, gingivitis, depression, peripheral neuropathy, and seizures.
Special Instructions
Fasting for 12 hours is required for patients, with collection before the next feeding for infants. Multivitamins or vitamin supplements should not be taken 24 hours prior to specimen collection. Ship specimen in an amber vial to protect it from light. If not ordering electronically, complete and send a General Request form with specimen.
Limitations
The test may be affected by vitamin supplementation and nonfasting as these can result in elevated plasma vitamin concentrations. Reference ranges are based on healthy fasting volunteers who abstained from vitamin supplements 24 hours before collection. Elevated PLP levels might be due to dietary supplementation, and interpretation requires careful consideration of reference intervals and possible confounding factors like supplementation compliance.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 30552-4
- 30552-4
Result Turnaround Time
2-7 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.75 mL
Container
Amber vial
Collection Instructions
Within 2 hours of collection, centrifuge at 4 degrees C. Aliquot all plasma into amber vial and freeze immediately.
Patient Preparation
12 hours fasting required. No multivitamins or supplements 24 hours before collection.
Storage Instructions
Ship in amber vial to protect from light.
Causes for Rejection
None listed apart from gross contamination, which is okay.
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 29 days |