Test ID PLP Pyridoxal 5-Phosphate, Plasma
Useful For
Determining vitamin B6 status, including in persons who present with progressive nerve compression disorders, such as carpal tunnel and tarsal tunnel syndromes
Determining the overall success of a vitamin B6 supplementation program
Diagnosis and evaluation of hypophosphatasia
Method Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Pyridoxal 5-Phosphate (PLP), PSpecimen Type
Plasma HeparinShipping Instructions
Ship specimen in amber vial to protect from light.
Specimen Required
Patient Preparation:
1. Fasting-overnight (12-14 hours) (infants-collect specimen prior to next feeding). Water can be taken as needed
2. For 24 hours prior to specimen collection, patient must not take multivitamins or vitamin supplements.
Supplies: Amber Frosted Tube, 5 mL (T915)
Collection Container/Tube: Green top (sodium or lithium heparin) or plasma gel separator (PST)
Submission Container/Tube: Amber vial
Specimen Volume: 1 mL
Collection Instructions:
1. Centrifuge at 4° C within 2 hours of collection
2. Aliquot all plasma into amber vial and freeze immediately
Specimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Heparin | Frozen | 29 days | LIGHT PROTECTED |
Reference Values
5-50 mcg/L
Day(s) Performed
Monday through Thursday, Saturday, Sunday
Report Available
1 to 4 daysPerforming Laboratory

Test Classification
This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
84207
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PLP | Pyridoxal 5-Phosphate (PLP), P | 30552-4 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
4047 | Pyridoxal 5-Phosphate (PLP), P | 30552-4 |
Forms
If not ordering electronically, complete, print, and send a General Request (T239) with the specimen.