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Holotranscobalamin

Alternative Names:

Active-B12

Laboratory:

Clinical Biochemistry

Test Code:

HOLOTC

Specimen Types:

Serum

Container Types:

SST

Collection & Request Instructions:

The transcobalamin-vitamin B12 complex (Holotranscobalamin) contains the biologically active cobalamin. A decrease of Holotranscobalamin is one of the earliest markers of cobalamin deficiency.

Retrospective testing - Note Sample MUST be Serum.

•• Specimens may be stored on or off the clot for up to 16 hours at room temperature or up to 3 days at 2-8°C.If testing will be delayed more than 3 days, remove serum from the clot and store at -20°C or colder. Avoid more than 3 freeze/thaw cycles.

Reference for Retrospective Testing: Abbott Alinity Active-B12, kit insert March 2019

Transport Instructions between Sites and/or Laboratories:

Room Temperature

Additional Notes:

Reference Interval: 25—165 pmol/L

Holotranscobalamin (HOLOTC) measures the biologically available fraction of Vitamin B12.

<25 pmol/L Vitamin B12 deficient

25-35 pmol/L Borderline low B12. Suggest review of clinical information together with confirmatory laboratory tests. For Further information contact Haematology registrars on ext 63075.

>35 pmol/L Vitamin B12 normal

Method: Abbott Alinity Active-B12

Reference Interval Alinity kit Insert Ref 09P2620, March 2019

Note: Active-B12 Reference Interval amended 18 March 2021