|Values are valid only on day of printing.|
See Vitamin B12 Deficiency Evaluation in Special Instructions.
This test provides a measurement of serum B12 level only. If a more comprehensive workup is preferred, consider ACASM / Pernicious Anemia Cascade.
The ACASM cascade simplifies the evaluation of B12 deficiency and ensures that additional testing is performed in patients with a decreased vitamin B12 level. The cascade begins with serum B12 measurement. If the vitamin B12 level is less than 150 ng/L, intrinsic factor-blocking antibody (IFBA) testing is automatically performed. If the IFBA test is negative or indeterminate, gastrin level is evaluated. If the serum vitamin B12 level is 150 to 400 ng/L, methylmalonic acid is measured. If the methylmalonic acid is greater than 0.40 units/L, IFBA testing is performed. If the serum vitamin B12 level is above 400 ng/L, no further testing is performed. See Vitamin B12 Deficiency Evaluation algorithm in Special Instructions.
Ask patients if they have received a vitamin B12 injection within the last 2 weeks. If patient has received an injection within the past 2 weeks, this test cannot be ordered.
Preferred: Serum gel
Acceptable: Red top
Specimen Volume: 0.6 mL
1. Serum gel tubes should be centrifuged within 2 hours of collection.
2. Red-top tubes should be centrifuged and aliquoted within 2 hours of collection.
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
Neurology Test Request Form-General (T732) (http://www.mayomedicallaboratories.com/it-mmfiles/neurology-request-form.pdf)
Benign Hematology Test Request Form (T755) (http://www.mayomedicallaboratories.com/it-mmfiles/benign-hematology-test-request-form.pdf)
Mild OK; Gross reject
Mild OK; Gross OK
|Serum||Refrigerated (preferred)||7 days|