Vitamin B1 (Thiamine), Serum/Plasma, LC/MS/MS

Test Code
VITB1 (90353)

Quest Code
90353

CPT Codes
84425

Preferred Specimen
2 mL frozen plasma collected in an EDTA (lavender-top) tube - protected from light

Patient Preparation
Overnight fasting is required

Minimum Volume
1 mL

Other Acceptable Specimens
EDTA plasma foil wrapped • Serum collected in a red-top tube (no-gel), protected from light

Instructions
Plasma (preferred): Collect blood in a (lavender-top) tube. Remove plasma within 4 hours of collection and transfer to a light protected pour off tube. If separation of cells can't be performed immediately after collection, keep the whole blood refrigerated and protected from light. The separation of cells must be completed within 4 hours of collection. Separate cells by centrifugation at 2-8° C for 8-10 minutes. Transfer plasma to amber tube to protect from light and freeze tube immediately. Alternately, neutral colored tubes can be used if wrapped in aluminum foil. Ship frozen tubes at -10° to -30° C.

Serum (acceptable): Collect blood in plain red top evacuated tube. Allow to clot at 20-25° C for 20-30 minutes. Centrifuge at 2-8° C for 8-10 minutes. Transfer serum to an amber polypropylene or polyethylene transport tube to protect from light and freeze tube immediately. Alternately, neutral colored polypropylene or polyethylene tubes can be used if wrapped in aluminum foil.

Transport Temperature
Frozen

Specimen Stability
Room temperature: 8 hours
Refrigerated: 48 hours
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Received room temperature • Received refrigerated • Hemolysis • Lipemia

Methodology
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Set up: Tue-Sat; Report available: 2-3 days

Reference Range
Adult 8-30 nmol/L


Clinical Significance
Vitamin B1 deficiency is most often associated with alcoholism, chronic illness and following gastric by-pass surgery. Prolonged deficiency causes beriberi. Plasma vitamin B1 is useful in evaluating nutritional assessment and compliance, while whole blood vitamin B1 is useful in evaluating body stores.

Performing Laboratory
Quest Diagnostics Nichols Institute
27027 Tourney Road
Valencia, CA 91355-5386



The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.