Vitamin B1 (Thiamine), Plasma/Serum, LC/MS/MS
Also known as: Thiamine, B1
Use
Vitamin B1 (thiamine) is required for branched‑chain amino acid and carbohydrate metabolism; deficiency often results from alcoholism or chronic illness, and early stages can present with anorexia, irritability, apathy, and generalized weakness, while prolonged deficiency may lead to beriberi.
Special Instructions
Whole blood is considered optimal specimen because thiamin diphosphate (TDP), the biologically active form, is primarily in erythrocytes; serum or plasma is acceptable but less optimal. Protect specimen from light; overnight fasting required.
Limitations
Test is a send‑out referral and optimal in whole blood; plasma/serum has lower TDP concentration. Not FDA cleared or approved; validated under CLIA. Light exposure, improper specimen handling (e.g., failure to freeze, unprotected from light) may lead to rejection or inaccurate results.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 2999-1
Result Turnaround Time
2-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2‑4 mL
Minimum Volume
1 mL
Container
Lavender (EDTA) tube; red‑top tube acceptable
Collection Instructions
Overnight fasting; protect from light; separate serum or plasma within 4 hours and freeze; protect from light.
Patient Preparation
Overnight fasting required.
Causes for Rejection
Received at room temperature; received refrigerated; hemolysis; lipemia; not protected from light
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 8 Hours |
| Refrigerated | 48 Hours |
| Frozen | 30 Days |
Other tests from different labs that may be relevant