Analysis of blood and urine at the level of vitamin D: the norm, why do they give up
Last reviewed: 19.10.2021
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Vitamin D is a vitamin, belonging to a group of biologically active substances, the synthesis of which is carried out in the skin under the influence of ultraviolet rays. This is the main way of penetration of vitamin D into the body, as an auxiliary it is considered the intake of it into the body with food and vitamin complexes. Sometimes the amount of vitamin can be much higher or lower than normal, which entails a number of diseases and negative consequences. The level of vitamin D in the body can be controlled. First you need to know its exact amount in the body. For this purpose, an analysis is made for vitamin D. It is recommended only for the doctor's prescription, if this is necessary.
Indications for the procedure of the analysis of vitamin D
The analysis is conducted for both children and adults. First of all, it is carried out in the event that there is a suspicion of a deficiency of this vitamin in the body. Usually hypovitaminosis D is accompanied by a decrease in appetite, irritability and tearful condition. There may be insomnia, intermittent, anxious sleep. Sharply reduced performance and increased fatigue.
Negatively, the vitamin D can also be hyper-sensitive, in which there is polyuria, diarrhea, nausea. Later, muscle tissue weakens, migraine develops, dizziness, indicating an intoxication of the body.
Assign in the event that a person has dystrophy, anorexia, or there is a sharp decrease in weight, which can not be controlled. The analysis is carried out with pancreatitis, with radiation enteritis, Crohn's disease, Whipple, with various gastritis. It is also performed for various types of metabolic disorders, including gluten enteropathy, hypophosphatemia, hypocalcemia, vitamin deficiency, hypovitaminosis and hypervitaminosis D, in cases of calcium metabolism disorders. If a person uses corticosteroids, continuous monitoring of vitamin D levels is necessary . Osteoporosis, disorders of the bone system of various types, and lupus erythematosus are the direct basis for the analysis.
Often the analysis is assigned to ensure regular monitoring during treatment with vitamins and mineral complexes, which makes it possible to monitor changes in dynamics, adjust the dosage.
If the clinical picture of a disease shows signs that indicate a lack of vitamin D, you should immediately carry out a study. This is often indicated by rickets in children, low bone mineralization. The analysis can be informative in dentistry: it is prescribed for caries, parodontosis, deformities of the teeth, bleeding gums. The deformity of the posture, weakness, tremor, stoop, convulsive and spasmodic conditions may indicate deficiency.
Why do I need vitamin D?
First of all, for the timely detection of pathology, take the necessary measures. Sometimes it is useful for the prevention of a deficiency or excess of vitamin D. The exchange of vitamin D and calcium is closely interrelated, so it allows timely detection of violations of calcium metabolism. In some cases, the parameters of vitamin D should be monitored in dynamics, for example, in the treatment of corticosteroids, vitamins, in the treatment of rickets, and other diseases. It is also important for the timely prevention of hypovitaminosis, because otherwise, osteoporosis may develop, the risk of fractures increases.
Where to pass the analysis on vitamin D?
Usually it can be taken in any laboratory, the list of services which includes analysis for vitamin D, or in the endocrinology center.
Preparation
There is no special, pre-planned training. The only thing that needs to be taken into account is that the analysis is performed on an empty stomach. You can eat in the evening, but in such a way that no less than 8-12 hours pass between the procedure and the analysis. At least a week before taking blood, you should not drink alcohol. You can stock up on the chocolate in advance, and eat it right after the procedure. This will improve the condition. You can after the procedure drink sweet tea with sugar.
Who to contact?
Technique of the analysis of vitamin D
After delivery to the laboratory of the material, a study is being conducted. The biological material is transferred to a centrifuge, clotting factors are removed, thus obtaining pure serum. Then, further study of the obtained serum is carried out. The study can be conducted by different methods. Most often use liquid chromatography or immunochemiluminescent analysis. Most often, the second option is used, because it is more convenient to use, it is much easier and faster. From the economic point of view, it is also more profitable.
The principle of the method consists in binding 25-hydroxycalciferol to paramagnetic particles that are coated with antibodies. After this, the particles precipitate with a magnet, and they are washed. A suspension is formed in which polyclonal antibodies and various reagents are added. As a result, complexes are formed that have luminescent properties. With the help of special equipment it is possible to estimate the intensity of luminescence. Based on these data, the concentration of vitamin D is calculated.
Blood test for vitamin D
The procedure begins with blood sampling from the vein. With all the rules of asepsis, venipuncture is performed, the necessary amount of blood is taken. The technique may vary somewhat, depending on the method used. In most cases, the blood is initially taken into a tube containing EDTA. This gel, which prevents blood clotting and changing its properties. After the procedure is completed, the puncture site is pressed down with a cotton ball, the arm is bent at the elbow and asked to hold in this position until the bleeding stops completely.
Blood can be stored for some time in a special box, in a sealed tube. In this form, it is usually transported to the laboratory. Frozen blood is not produced.
[15], [16], [17], [18], [19], [20]
Urine analysis for vitamin D
The vitamin D content is often examined by urine analysis. A Sulkovich sample is used for the determination. It makes it possible to reveal the calcium content in the blood, on the basis of which they draw further conclusions about the content of vitamin D.
The results of the analysis are qualitative, defined as follows: "-" indicates a deficiency of vitamin D, "+" or "++" indicates a norm, "+++" indicates excessive content.
Analysis for calcium and vitamin D
It allows to determine the presence of calcium in the urine. According to these data, it is possible to judge the peculiarities of the metabolism of vitamin D. The study was called Sulkovich's trial, or completely urine analysis by the Sulkovich method. Gives information only about whether there is calcium in the urine. In what quantity it is allocated, it is impossible to determine.
Especially important is the analysis for children, because they have a high risk of abnormal development, the occurrence of rickets with a lack of vitamin D and a violation of calcium metabolism. If the child was born in winter or autumn, this risk increases because of the lack of sunlight. If a deficiency is found, the vitamin should be added to the body artificially, and it is important to control the dosage. The drawback entails breaking the bones, reducing strength. Most often these are the first signs of rickets. Subsequently, rickets are manifested in the form of curved legs, a disproportionately large head, a forward belly. Measures should be taken urgently, otherwise the ossification of the skeleton will occur and the person will remain with such pathologies for life.
Excess calcium is also dangerous. Develops convulsive syndrome, aesthetic appearance is disrupted. Excess calcium and vitamin are deposited in the bones, as a result of which their growth slows down significantly.
[21], [22], [23], [24], [25], [26], [27]
Analysis for vitamin D 3
The most accurate content of vitamin D can be determined by the amount of vitamin D 3 (25-hydroxyvitamin D 3 ) . Usually, a comprehensive study is conducted, during which this parameter is determined. The fact is that the complex analysis of "25 OH D3" implies the study of the two components of this vitamin - D2 and D3. The source of vitamin D2 is food, while ultraviolet rays also serve as a source of vitamin D3. The study is subject to serum.
[28], [29], [30], [31], [32], [33], [34], [35]
Analysis for the assimilation of vitamin D
The most accurate picture describing the nature of the absorption of vitamin D in the body can be obtained by conducting a comprehensive blood test. Children have enough urine analysis.
Analysis for vitamin D to the baby
For children with a view to determining vitamin D, urine tests are performed. The method is simple, does not require any preliminary preparation. It is only necessary to collect the morning urine and carry it to the study. Urine is collected in the morning, immediately after the baby woke up after a long sleep. This is done before the child begins to drink or eat. For young children use urinals, acting as a reservoir for urine. Urine dumps are disposable.
The technique of the study is also not difficult. In the laboratory, the urine is mixed with a Sulkovich reagent, which is a mixture of calcium salts and oxalic acid. As a result, there is turbidity, the degree of severity of which is judged about the presence or absence of calcium in the urine. If this result does not fully clarify the clinical picture of the pathology, or it is not enough to diagnose, predict, investigate daily urine.
Analysis for vitamin D adults
Adults determine the vitamin content in venous blood. With the help of simple laboratory technology, the concentration of vitamin in the serum is detected. In adults, impaired calcium metabolism is fraught with numerous serious disorders. The main violation is osteoporosis. In the body of an adult vitamin D takes part not only in the exchange of calcium, but also in the exchange of phosphorus. As a result of deficiency, muscle weakness, tremor develops. Violated the work of all internal organs, including kidneys, muscles. Violated regulation of blood pressure, normal activity of the heart.
A normal amount of vitamin D is necessary for the proper functioning of the thyroid gland. The immune system rises, blood coagulability normalizes. The exchange of other vitamins and microelements also depends on the normal content of vitamin D. With a low or excessive vitamin content, the work of the kidneys and liver can be disrupted.
One of the important properties is the provision of normal cell multiplication, in which their uncontrolled division does not occur. Blocking uncontrolled reproduction of cells is the key to successful treatment and prevention of cancer. Also, the activity of the immune system increases, resulting in the suppression of autoimmune diseases. This property provides prolongation of life in immunodeficiencies and AIDS.
[43], [44], [45], [46], [47], [48], [49], [50]
Analysis of vitamin D in pregnancy planning
The analysis is mandatory for pregnant women, it is planned. This is due to the fact that this vitamin is very important for both the mother and the future child. Promotes the normal exchange of calcium and phosphorus, regulates the multiplication and division of cells, their differentiation. Takes part in the synthesis of hormones. Forms in the main degree the skeleton of the unborn child. Prevents the development of varicose veins in the mother, preserves the beauty and health of hair, nails, teeth. If there is a lack of vitamin D in the body of a pregnant woman, a child with a tendency to rickets may develop. Usually pregnant, and also during pregnancy planning, women are prescribed vitamin D. Its exact concentration, can only be determined by analysis. Also, the analysis is needed to control these indicators in dynamics, since the amount of vitamin should be adjusted to prevent either a lack or an overdose.
[51], [52], [53], [54], [55], [56], [57], [58], [59], [60], [61], [62], [63], [64]
How much analysis is done for vitamin D?
The analysis is done pretty quickly. Usually it takes 1 working day, less often - two. In many clinics, the results are reported immediately by telephone or e-mail.
Normal performance
Normally, the concentration of vitamin D can vary within fairly wide limits: from 30 to 100 ng / ml. The indices below 10 ng / ml indicate a deficiency of vitamin D, values above 100 ng / ml indicate an excessive vitamin D. This indicates a possible intoxication of the body. The units of measurement may vary. If the measurements were made in nmol / l, the norm values will be 75-250 nmol / l.
The device for analysis
There is a special apparatus that allows a complex study of tissue density, calculate the content of calcium and vitamin D. The procedure is called densitometry and is one of the varieties of the radiographic method of investigation.
It allows you to quickly and effectively detect osteoporosis, to determine the density of bone tissue in general, and each individual segment of it. This makes it possible to predict possible fractures, to determine the risks of predicting existing fractures. It is most often used for hip fractures, since this trauma is very dangerous for life and health in old age. The study using this device is applied to women during the menopause, especially if they are high in diabetes. Also carried out in the event that a person takes medications that promote the excretion of calcium from the body.
Raising and lowering of values
When the values are higher than normal, the result is positive. This indicates an overdose of vitamin D and manifests itself as intoxication. There is a loss of appetite, vomiting, weakness. The sleep can be dramatically disturbed, the body temperature can rise.
If the values are lower than normal, the result is negative. This may indicate the development of such serious pathologies as cirrhosis, renal failure, osteitis, thyrotoxicosis, inflammation of the intestine, rickets. Also, the vitamin D content may decrease as a result of taking certain medications, for example, anticonvulsants, glucocorticosteroids. Analysis for vitamin D may be negative during pregnancy and during lactation.