VITAMIN B6 LEVEL
- VITAMIN B6 LEVEL
- Start Date
- Expiration Date
- B6 Vitamin, Pyridoxal 5-Phosphate, Pyridoxal Phosphate
- CPT Codes
- Reference Test
Spec Type: Plasma - frozen
Spec Container: Green top (heparin) or light green top (PST) tube
Alt Spec Type: Serum - frozen
Alt Spec Container: Red top (serum) tube
- Transport Info
Promptly centrifuge 15 minutes
Immediately transfer plasma or serum to separate amber plastic tube and freeze
Spec Store Transport:
Protect from light
After separation from cells:
Room temperature: Unacceptable
4 hours refrigerated (2-8°C)
2 months frozen (-20°C) (Avoid repeated freeze/thaw cycles)
- Fasting Required?
- Patient Instructions
Collect specimen after an overnight fast
- Reference Range
Pyridoxal 5'-phosphate measured in a specimen collected following an 8 hour or overnight fast accurately indicates vitamin B6 nutritional status. Non-fasting specimen concentration reflects recent vitamin intake.
The biologically active form of vitamin B6, pyridoxal 5-phosphate, is measured in this assay.
Quantitative High Performance Liquid Chromatography (HPLC)
Vitamin B6 (pyridoxal 5´-phosphate, PLP) is a coenzyme involved in a variety of biochemical processes (i.e., metabolism of proteins, carbohydrates, and lipids). Dietary deficiency of vitamin B6 is uncommon. A more common cause of deficiency is the ingestion or use of antagonists such as isoniazid, hydralazine, cycloserine, and penicillamine. As deficiency progresses, electroencephalographic (EEG) changes appear that may be associated with epilepsy, especially in young patients. Skin changes include dermatitis, cheilosis, and glossitis. Sideroblastic anemias have been described that are responsive to vitamin B6 administration.This assay does not distinguish between pyridoxine, pyridoxamine, and pyridoxal forms, and does not detect pyridoxic acid.