Feb 8, 2018




Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Chemistry

Vitamin B12

Vitamin B12 (B12) Chemistry Lab Test

Name: Vitamin B12

Test Name: Vitamin B12

Health Link Test Code: B12

LIS Test Code: B12

CPT Code(s): 82607

Methodology: Chemiluminescent Immunoassay

Days Performed: Daily.

In-Lab Turnaround Time: 4 hours.

Stat In-Lab Turnaround Time: Not available stat.

Specimen: Blood

Collection Container: Red cap with yellow ring (SST)

Also Acceptable: Red top

Collection Volume: 1 mL

Pediatric Collection Volume: 0.5 mL

Stability Ambient:

3 days

Stability Refridgerated:

7 days

Stability Frozen:

>7 days

Sample Analyzed: Serum

Testing Volume: 0.5 mL

Pediatric Testing Volume: 0.2 mL

Specimen Processing:

Centrifuge blood within 2 hours. Transfer cell-free serum to plastic vial. Refrigerate. If transport time exceeds 48 hours, freeze serum sample.

Specimen Transport:

Transport specimen to Laboratory. Transport with coolant pack if coming from clinic location. Transport frozen specimen on dry ice.

Unacceptable Criteria:

Hemolyzed specimens are not acceptable.


18 years and up: 213-816 pg/mL

Interpretation Type: Reference Interval

Test Limitations:

Intrinsic Factor blocking antibodies are present in approximately half of pernicious anemia patients. There is a low frequency possibilty that these antibodies may not be completely inactivated during the reaction pretreatment step. If test results are in conflict with the clinical diagnosis, consider testing for intrinsic factor blocking antibodies.


Patient samples may contain heterophilic antibodies that could react in immunoassays to give falsely elevated or depressed results. A test result that is inconsistent with the clinical picture and patient history should be interpreted with caution.


Additional Information:

Special Instructions: Effective 7/3/17, the acceptable tube type for Vitamin B12 Testing is SST or Red Top tube. This is due to an artifact identified in the green top tubes that caused occasional spuriously high results.