Skip Ribbon Commands
Skip to main content
Sign In

25415 Vitamin B6 Pyridoxal 5-Phosphate (PLP), in Serum

Vitamin B6 Pyridoxal 5-Phosphate (PLP), in Serum
Test Code: VITB6
Synonyms/Keywords
​B6 (Vitamin), PALP (Pyridoxal 5-Phosphate), Pyridoxal 5-Phosphate (PALP), Pyridoxal Phosphate, Vitamin B6, PLP
Useful For
​Determining vitamin B6 status and the overall success of a vitamin B6 supplementation progam.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
Yes​ ​Serum ​Red Top Tube (RTT) ​Heparin Green Top Tube (GTT) ​0.5 mL ​0.25 mL ​0.15 mL
Collection Processing Instructions
​1) Fasting overnight (at least 9 hours) (infants, draw prior to next feeding)
2) Patient should not ingest vitamin supplements for 24 hours before specimen is drawn.
3) Foil wrap sample after collection and processing.
4) Remove serum/plasma from cells promptly after collection.  Protect aliquot from light.
5) Use of gel separator tubes are discouraged, but will not be rejected so long as serum/plasma is removed from
    gel barrier within 12 hours of collection.
Specimen Stability Information
Specimen Type Temperature Time
Serum/Plasma ​ ​ ​ ​Frozen

​​At least 1 month

​Refrigerate​up to 24 hours
Rejection Criteria
​​EDTA Lavender Top Tube (LTT)
Serum Separator Tube (SST)/Plasma Separator Tube (PST)​ on gel >12 hours
​Serum/plasma not protected from light >12 hours
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield 1 day/week: Monday ​2 - 4 hours ​Liquid Chromatography-Tandem Mass Spectrometry (UPLC MS/MS)
Samples must be in performing department by 8am on day of testing for results the same day.​ ​ ​ ​​ ​ ​ ​
Test Information
This test was developed and its performance characteristics determined by Marshfield Labs.  It has not been cleared or approved by the US Food and Drug Administration.  This test is used for clinical purposes.  It should not be regarded as investigational or for research.
  

Vitamin B6 is a complex of 6 vitamers: pyridoxal, pyridoxol, pyridoxamine, and their 5'-phosphate esters. Due to its role as a cofactor in a number of enzymatic reactions, pyridoxal phosphate (PLP) has been determined to be the biologically active form of vitamin B6.

Vitamin B6 deficiency is uncommon and due to its function as a cofactor in many reactions of amino acid metabolism., it can have a wide range of symptoms including anemia, itchy rashes, scaly skin on the lips, cracks at the corners of the mouth, swollen tongue, depression, confusion, and a weak immune system. Infants who do not get enough vitamin B6 can become irritable, develop extremely sensitive hearing, or experience seizures.

Reference Range Information
Performing Location Reference Range
Marshfield​ ​5-50 ug/L
Interpretation
​Levels for fasting individuals falling in the range of 5 to 50 ug/L for pyridoxal-5'-phosphate (PLP) are indicative of adequate nutrition.
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
84207​
Classification
This test was developed and its performance characteristics determined by Marshfield Labs.  It has not been cleared or approved by the US Food and Drug Administration.  This test is used for clinical purposes.  It should not be regarded as investigational or for research.
Synonyms/Keywords
​B6 (Vitamin), PALP (Pyridoxal 5-Phosphate), Pyridoxal 5-Phosphate (PALP), Pyridoxal Phosphate, Vitamin B6, PLP
Ordering Applications
Ordering Application Description
​COM ​Vitamin B6, Pyridoxal-5-Phos
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
Yes​ ​Serum ​Red Top Tube (RTT) ​Heparin Green Top Tube (GTT) ​0.5 mL ​0.25 mL ​0.15 mL
Collection Processing
​1) Fasting overnight (at least 9 hours) (infants, draw prior to next feeding)
2) Patient should not ingest vitamin supplements for 24 hours before specimen is drawn.
3) Foil wrap sample after collection and processing.
4) Remove serum/plasma from cells promptly after collection.  Protect aliquot from light.
5) Use of gel separator tubes are discouraged, but will not be rejected so long as serum/plasma is removed from
    gel barrier within 12 hours of collection.
Specimen Stability Information
Specimen Type Temperature Time
Serum/Plasma ​ ​ ​ ​Frozen

​​At least 1 month

​Refrigerate​up to 24 hours
Rejection Criteria
​​EDTA Lavender Top Tube (LTT)
Serum Separator Tube (SST)/Plasma Separator Tube (PST)​ on gel >12 hours
​Serum/plasma not protected from light >12 hours
Useful For
​Determining vitamin B6 status and the overall success of a vitamin B6 supplementation progam.
Reference Range Information
Performing Location Reference Range
Marshfield​ ​5-50 ug/L
Interpretation
​Levels for fasting individuals falling in the range of 5 to 50 ug/L for pyridoxal-5'-phosphate (PLP) are indicative of adequate nutrition.
For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield 1 day/week: Monday ​2 - 4 hours ​Liquid Chromatography-Tandem Mass Spectrometry (UPLC MS/MS)
Samples must be in performing department by 8am on day of testing for results the same day.​ ​ ​ ​​ ​ ​ ​
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
84207​
Classification
This test was developed and its performance characteristics determined by Marshfield Labs.  It has not been cleared or approved by the US Food and Drug Administration.  This test is used for clinical purposes.  It should not be regarded as investigational or for research.
For most current information refer to the Marshfield Laboratory online reference manual.