Test Code B12 Vitamin B12 Assay, Serum
Reporting Name
Vitamin B12 Assay, SUseful For
Investigation of macrocytic anemia
Workup of deficiencies seen in megaloblastic anemias
Testing Algorithm
For more information see Vitamin B12 Deficiency Evaluation.
Method Name
Immunoenzymatic Assay
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumOrdering Guidance
Ask patients if they have received a vitamin B12 injection or radiolabeled vitamin B12 injection within the last 2 weeks. Patient results will not reflect deficiency or malabsorption after recent B12 injection. If patient has received such an injection within the past 2 weeks, this test should not be ordered.
This test provides a measurement of serum vitamin B12 level only. For a more comprehensive workup, order ACASM / Pernicious Anemia Cascade, Serum, which initiates testing with measurement of vitamin B12. Depending on the vitamin B12 concentration, testing for intrinsic factor blocking antibody, gastrin, and methylmalonic acid may be added.
Necessary Information
Ask patients if they have received a vitamin B12 injection within the last 2 weeks. Patient results will not reflect deficiency or malabsorption after recent B12 injection. If patient has received an injection within the past 2 weeks, this test should not be ordered.
Specimen Required
Patient Preparation: This test should not be performed on patients who have received a vitamin B12 injection or radiolabeled vitamin B12 injection within the previous 2 weeks.
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.6 mL
Collection Instructions:
1. Serum gel tubes should be centrifuged within 2 hours of collection.
2. Red-top tubes should be centrifuged, and the serum aliquoted into a plastic vial within 2 hours of collection.
Specimen Minimum Volume
0.5 mL
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 90 days |
Special Instructions
Reference Values
180-914 ng/L
Day(s) Performed
Monday through Saturday
CPT Code Information
82607
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
B12 | Vitamin B12 Assay, S | 2132-9 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
B12 | Vitamin B12 Assay, S | 2132-9 |
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.Report Available
1 to 3 daysForms
If not ordering electronically, complete, print, and send a Benign Hematology Test Request (T755) with the specimen