VITAMIN B6 LEVEL
- Code
- 900.5550
- Name
- VITAMIN B6 LEVEL
- Category
- None
- Department
- Send-Out
- Start Date
- Expiration Date
- Synonyms
- B6 Vitamin, Pyridoxal 5-Phosphate, Pyridoxal Phosphate
- CPT Codes
- 84207
- Site
- SBMF
- Reference Test
- 44322
Specimen Information
- Type
Red, Plain
- Volume
1.0 ml
- Transport Info
CRITICAL FROZEN – Separate samples must be submitted when multiple tests are ordered
Protect from light during collection, storage, and shipment
Separate plasma or serum from cells and freeze ASAP, or within 2 hours of collection
Specimens collected in EDTA yield a higher pyridoxal 5'-phosphate concentration, therefore EDTA is not acceptable
Centrifuge and immediately transfer serum to separate light protected or foil wrapped plastic tube
Frozen- Fasting Required?
- True
- Patient Instructions
Collect specimen after an overnight fast
- Reference Range
20-125 nmol/L
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.Note:
The biologically active form of vitamin B6, pyridoxal 5-phosphate, is measured in this assay.- Methodology
Quantitative High Performance Liquid Chromatography (HPLC)
Clinical Significance
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.