How Does Vitamin B12 Testing Work?
Vitamin B12 testing is performed through venipuncture, typically entering at the back of the hand or inner elbow veins. Lancets are often used on infants or small children, collecting the specimen in a test strip or on a slide rather than a blood vial. Most commonly and accurately, analyzing the specimen for picograms per milliliter (pg/mL) will determine the subject's lack of B12 or normalcy. Though other measurements do exist, they increase the occurrence of false-normal readings (see "weaknesses" below).
Normal values for B12 in the blood will fall into the 200 - 900 pg/mL range and may differentiate or fluctuate based on variables within the lab. If a subject's level falls below the 200 pg/mL range, they are said to show signs of a vitamin B12 deficiency. At this level, it is likely the subject will already exhibit symptoms.
Causes for Vitamin B12 Deficiency
The causes for Vitamin B12 deficiency can be determined by a Shilling Test and include (but are not limited to):
● Lack of B12 in diet
● Malabsorption diseases and conditions (e.g. celiac and Crohn's disease)
It is uncommon for B12 levels to be in excess of 900 pg/mL as urination typically clears the body of excess waste. Still, excessive B12 levels might indicate a number of dangerous conditions including hepatitis or cirrhosis of the liver.
What are the Weaknesses of Vitamin B12 Testing?
The patient-side weaknesses of vitamin B12 testing include the typical risks of phlebitis and hematoma which arise during any venipuncture, but the greater concern arises during the analysis. A rupture of any red blood cells (hemolysis) during the collection of the sample can have an impact on the results of the test.
False-normal results can also occur from poor measurement methods, though they have decreased in occurrence with the increase in popularity of measuring the pg/mL range. This is because the pg/mL range only measures biologically active B12.
Recently developed blood tests utilize a mass spectrometry based technique to determine the overall aldosterone level. As such IsoSciences offers an unlabeled form and is currently developing a labeled form of Vitamin B12. If you wish to discuss purchase of this molecule, please contact us by email or phone (610-337-3762) we will be more than happy to provide assistance.
Vitamin B12 Testing