Sign in →

Test Code TDP Thiamine (Vitamin B1), Whole Blood

Important Note

Protect specimen from light

Additional Codes

Epic Ordering Code LAB3040184
NBS code LBC00911
Service code 36939

Reporting Name

Thiamin (Vitamin B1), WB

Specimen Type

Whole Blood EDTA


Shipping Instructions


Ship specimen in amber vial or tube to protect from light.



Specimen Required


Patient Preparation:

1. Fasting: 12 hours, required; Infants should have specimen collected before next feeding, water can be taken as needed

2. For 12 hours before specimen collection, patient should not take vitamin supplements.

Supplies: Amber Frosted Tube, 5 mL (T915)

Collection Container/Tube: Lavender top (EDTA)

Submission Container/Tube: Amber vial

Specimen Volume: 4 mL

Collection Instructions:

1. Invert 8 to 10 times to mix whole blood.

2. Transfer whole blood into amber vial or tube and freeze within 24 hours of collection.


National University Hospital-Singapore Note:

NUH Outreach Laboratories:
Specimen Requirements
Submit the following:
Container: Purple Top
Fasting: 12 hours, required; Infants should have specimen collected before next feeding, water can be taken as needed.
For 12 hours before specimen collection, patient should not take vitamin supplements.
Processing Requirements
Gently invert to mix the whole blood and aliquot into Mayo Amber Tube. Freeze immediately.
Specimen type: Whole Blood
Volume: 4 mL
Storage/transport requirements: Frozen

Forms

If not ordering electronically, complete, print, and send a General Request (T239) with the specimen.

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole Blood EDTA Frozen 28 days LIGHT PROTECTED

Reject Due To

Gross lipemia Reject
Glass vial Reject
Clotted specimen Reject

Method Name

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

Day(s) Performed

Monday through Friday

Report Available

3 to 6 days
National University Hospital-Singapore Note:

Please note that this is a referral test requiring transport to the external testing facility and an additional 3-5 days is required.

Reference Values

70-180 nmol/L

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Useful For

Assessment of thiamine deficiency

 

Measuring thiamine levels in patients with behavioral changes, eye signs, gait disturbances, delirium, and encephalopathy; or in patients with questionable nutritional status, especially those who appear at risk and who also are being given insulin for hyperglycemia

CPT Code Information

84425

LOINC Code Information

Test ID Test Order Name Order LOINC Value
TDP Thiamin (Vitamin B1), WB 32554-8

 

Result ID Test Result Name Result LOINC Value
85753 Thiamin (Vitamin B1), WB 32554-8

Secondary ID

42356

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
National University Hospital-Singapore Additional Information:

Last updated 06/08/2026