Vitamin B1

Label Mnemonic:	VTB1B
Epic code:	LAB125
Order form:	Laboratory Requisition
Supply order:	Supply Order Form
Billing:	Billing Policies
CPT code:	84425

Specimen(s):

Whole Blood

Collection Medium:

Green top tube 4 mL (Na Heparin)

Minimum:

Preferred Minimum: 3 mL whole blood from green top (NA Heparin) tube.
Absolute Minimum: 0.6 mL whole blood from green top (NA Heparin) tube.

Rejection Criteria:

Any specimen other than whole blood. Plasma separator tubes. Glass tubes. Clotted or non-frozen specimens.

Turn Around Time:

2-4 days upon receipt at reference laboratory

Reference Range:

70-180 nmol/L

Interpretive Data:

This assay measures the concentration of thiamine diphosphate (TDP), the primary active form of vitamin B1. Approximately 90 percent of vitamin B1 present in whole blood is TDP. Thiamine and thiamine monophosphate, which comprise the remaining 10 percent, are not measured.

Comments:

Whole blood is the preferred specimen for thiamine assessment. Approximately 80 percent of thiamine present in whole blood is found in red blood cells.

Do not use to monitor thiamine supplementation. Use to determine thiamine deficiency.

Methodology:

Quantitative High Performance Liquid Chromatography

Instructions:

After collection, place in wet ice and immediately deliver to laboratory. Critical Frozen. Specimen is not stable at room temperature. Only stable for 4 hours refrigerated. Separate specimens must be submitted when multiple tests are ordered.

Sample Processing:

Label transport tube with patient last name, first name, identification number, date and time of collection.
Submit whole blood in original container. DO NOT CENTRIFUGE.

Sample Storage:

Store whole blood frozen.

Transport Instructions:

Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place completed requisition into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container to maintain frozen temperature.

CPT Code:

84425