Vitamin B12 (Cobalamine)

Vitamin B12 (Cobalamine)

B12 contains a mineral, cobalamin, and is sometimes referred to as cyancobalamin. The test is run on serum, usually in conjunction with folate (folic acid). B12 is a water-soluble vitamin. It is necessary for DNA and red blood cell synthesis, new cell growth, maintenance of nervous tissue and glucose metabolism. It is also one of the vitamins (along with B6 and folate) essential to convert homocysteine back to methionine. Decreased levels can cause anemia (pernicious anemia), fatigue, irritability, loss of appetite, labored breathing, constipation, heart palpitations, headache and "sore tongue." Some congenital defects have been linked to low B12 levels.

It is found in liver, oysters, poultry, fish, clams, salmon and eggs. B12 tends to be low in vegans.

The RDA is 2.4 micro grams. A supplemental level is 3 to 1000 micrograms. There is no toxic dose listed for B12.

Specimen required is 1.0 mL of serum, protected from light.

Doctors who wish to order kits, please call our lab directly to set up an account before ordering. 316-684-7784

Process time: 5 to 7 business days

Process method: The methodology is an RIA method using a 57CO as a label and is performed on serum or plasma.

CPT code: 82607

Special instructions: None

Rejection causes: Hemolysis

Patient prep: None

Specimen volume: 1 mL serum; light protected

Minimum volume: 0.2 mL

Collection container: SST or red-stopper tube

Transport container: Amber plastic transport tube

Transport instructions: Refrigerate or freeze

Normal values: The normal value established in our laboratory for B12 is 165 to 1100 pg/mL.

Reference one: Allen R: Megaloblastic anemias, in Wyngaarden JB, et al. Editors, 1992; Cecil Textbook of Medicine, Philadelphia, W.B. Saunders Co., 19th ED:847-856

Reference two: Beuerlein F: Testing strategies for anemias. 1988; Lab Manag; December: 23-28.

Reference three: Herbert V: The five possible causes of all nutrient deficiencies: illustrated by deficiencies of vitamin B12 and folic acid; 1973; Am J Clin Nutr; 26:77-78.