Vitamin B12 measurement is used to check hypovitaminosis, monitor supplement therapy, and investigate patients with macrocytic or megaloblastic anemia.
Vitamin B12 (cyanocobalamin) is a water-soluble vitamin derived from foods of animal origin and is essential for the synthesis of deoxyribonucleic acid (DNA) in the body. It can be absorbed from the gastrointestinal tract only when the endogenous factor, a glycoprotein secreted by the stomach parietal cells, is present. Although the body has a 12-month stock of vitamin B12 in the liver, kidneys, and heart, in conditions of rapid growth or in conditions that cause an increase in cell metabolism, the body's needs for vitamin B12 increase.
Symptoms of vitamin B12 deficiency include anemia, red and sore tongue (glossitis), and neurological abnormalities.
Possible Interpretations of Pathological Values
- Increase: Chronic obstructive pulmonary disease, congestive heart failure, diabetes, hepatic cell damage, leukemia (chronic granulocytic), obesity, true polycythemia, renal failure (chronic)
- Decrease: Anemia (malignant), atrophic gastritis, small intestinal bacterial overgrowth syndrome (SIBO), congenital transcobalamin II deficiency, Crohn's disease, gastrectomy or gastric bypass (removal of the parietal cells), hepatitis (alcoholic), ileal diseases, inflammatory bowel diseases, tapeworms and other intestinal parasites and worms, endogenous factor deficiency (malignant anemia), malabsorption, malnutrition, pancreatic insufficiency, sickle cell anemia, (severe) vegetarianism. Medications: p-aminosalicylic acid, antibacterials (neomycin), colchicine, omeprazole
See also