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At a Glance
Why Get Tested?
To help detect early and/or mild vitamin B12 deficiency; to help diagnose methylmalonic acidemia, a rare inherited metabolic disorder
When to Get Tested?
When you have a low vitamin B12 level and/or have symptoms of B12 deficiency such as numbness, tingling in the hands or feet, trouble walking, swelling of body tissues, or yellowing of the skin or eyes; as part of newborn screening
Test Preparation Needed?
You may be instructed to fast before sample collection for this test.