Cyanocobalamin (Vitamin B12)
Why this test?
Foremost, to identify the causes of macrocytic anemia.
To assess the state of health and nutritional balance of patients with signs of malnutrition and malabsorption, people suffering from alcoholism or various forms of malabsorption (celiac disease, Crohn's disease).
In case of elderly people, a B12 test can help determine the cause of changes in the psyche and behavior.
For patients suffering from vitamin B12 deficiency, regular determination of its concentration allows monitoring the treatment process. This is especially relevant for people with congenital defects in the absorption of vitamin B12, forced to take drugs all their lives.
In what cases is it prescribed?
If during a general blood test performed routinely or as part of the diagnosis of anemia symptoms, erythrocytes of increased size are detected.
When identifying the causes of changes in behavior: the appearance of irritability, confusion, depression and / or paranoia (especially in the elderly).
With non-specific symptoms indicating vitamin B12 deficiency, such as dizziness, weakness, fatigue, changes from the gastrointestinal tract (glossitis, liver enlargement).
If necessary, check for B12 deficiency in patients with various neurological disorders: paresthesia and numbness of the hands and / or feet, impaired sensitivity, peripheral neuropathy.
When examining the health of patients suspected of insufficient nutrition or impaired absorption of vitamin B12, with various intestinal diseases.
When B12 deficiency is detected in a breastfed child, it is necessary to examine its mother for a lack of this vitamin.
Periodic control of the B12 level allows to assess the effectiveness of vitamin deficiency treatment.
Test information
Determining the concentration of vitamin B12 in blood serum is a standard method of diagnosing its deficiency.
Vitamin B12 is found exclusively in products of animal origin, such as meat (especially liver and kidneys), fish, eggs, and dairy products. In recent years, cereals, bread, breakfast cereals and other cereal products enriched with vitamin B12 have become an important source of vitamin B12, especially for vegetarians.
B12 is important for the synthesis of nucleic acids, the formation of erythrocytes, cellular and tissue metabolism, and it is also involved in maintaining the normal functioning of the nervous system. A deficiency of vitamin B12 can lead to the development of macrocytic (megaloblastic) anemia. Its main manifestation is a decrease in the number of erythrocytes in the blood, but at the same time an increase in their size - the formation of macrocytes. Macrocytes, as a rule, have a shorter life span compared to normal erythrocytes and are more prone to hemolysis, which leads to fatigue, weakness and other symptoms of anemia. A lack of vitamin B12 threatens with damage to the nervous system (funicular myelosis), which manifests itself in the form of tingling in the patient's legs and hands (distal paresthesias), sensitivity disorders, increased tendon reflexes.
The main causes of vitamin B12 deficiency in the body:
Insufficient income. B12 accumulates mainly in the liver and spleen. Since the reserves of this vitamin in the body are quite large, and the elimination is slow, it takes about 5 years of insufficient intake of it in the body to create a significant deficit. Accordingly, risk groups are starving people and vegetarians.
Violation of absorption. B12 deficiency sometimes occurs with various diseases of the small intestine that disrupt the absorption of this vitamin (celiac disease, Crohn's disease, decreased acidity of gastric juice (achlorhydria), as well as with a decrease in the reabsorbing surface after resection of the small intestine. However, the most common cause of B12 deficiency is pernicious anemia. The basis of this disease is the congenital inability of the stomach to secrete substances necessary for the absorption of vitamin B12 in the intestines.
Violation of disposal. Various diseases of the liver and kidneys, as well as alcohol abuse, lead to a decrease in the accumulation and increase in the release of vitamin B12.
Increasing the body's need for vitamins. With various diseases that require a large amount of vitamin B12, for example, hemolytic anemia, hyperthyroidism and alpha-thalassemia.
