How and why to take a blood test for calcium - decoding indicators and norms. The purpose of a blood test for calcium Calcium in men 2.61 which means

Update: October 2018

Calcium (Ca) is one of the most important macronutrients for the human body, involved in the construction of tissues and metabolism. The element ranks fifth in the list of all minerals found in the body, accounting for about 2% of a person's weight.

The role of calcium in the body cannot be overestimated. In addition to the well-known building material for bones and teeth, the macronutrient regulates the contractile function of the heart, nourishes the nervous tissue and participates in impulse conduction, lowers cholesterol, regulates arterial pressure, takes part in the transportation nutrients cell membranes and much more.

Calcium is extremely important for pregnant women - only with its proper intake, the physiological development of the fetus and the normal state of health of the expectant mother are ensured.

The amount of calcium in the body

In newborns, there is about 30 grams of calcium in the body. Gradually, the amount of calcium increases in adults and is approximately 1000-1200 g (for an average weight of 70 kg). The daily intake of calcium from food depends on age and gender:

Reasons for the development of calcium deficiency

Behavioral and external causes

• Insufficient intake of calcium from food, which is often observed when following certain diets for weight loss, unbalanced nutrition, vegetarianism, starvation, neglect of dairy products, etc.
• Low calcium content in water.
• Smoking, excessive passion for coffee (accelerate the excretion of Ca).

Diseases, pathological conditions

• Violation of the absorption of a macronutrient in the intestine, which occurs against the background of dysbacteriosis, candidiasis, food allergies, chronic enterocolitis, etc.
• Diseases of the kidneys, hematopoietic system, pancreas (pancreatitis), thyroid gland (familial, idiopathic, postoperative hypoparathyroidism, in which hypocalcemia develops due to increased production of parathyroid hormone by the parathyroid glands).
• Lack of estrogen
• Rickets
• (dairy and other products containing the element).

Metabolic disorders

• Excess in the body of the following elements: lead, zinc, phosphorus, magnesium, iron, cobalt, potassium and sodium, which contribute to the excretion of calcium.
• Deficiency in the body of vitamin D3, which is involved in the assimilation of the element and its incorporation into cell structures (the norm for an adult is from 400 to 800 IU).

Other reasons

• An increased need for an element that is observed during a period of accelerated growth, during pregnancy and lactation (calcium is used to build fetal tissues or enrich breast milk), increased physical and mental stress (accelerated consumption), menopause (lack of estrogen that absorbs calcium).
• Old age (impaired absorption of calcium).
• Treatment with diuretics and laxatives (accelerated elimination).

Symptoms of calcium deficiency in the body

• Weakness, fatigue, decreased performance.
• Nervousness, irritability.
• Dryness and peeling of the skin, brittle nails. Increased sweating of the scalp.
• Tooth decay, caries.
• Numbness of the fingers, face, cramps, pain in the legs and arms.
• - fragility of bones, frequent fractures or cracks, deformation of bones.
• Violation of cardiac activity up to the development of heart failure, tachycardia.
• Subcapsular (with prolonged hypocalcemia).
• Increased bleeding, impaired blood clotting.
• Reduced immunity, which is expressed by frequent infections.
• Hypersensitivity to cold weather(aches in bones and muscles, chills).
• Signs of calcium deficiency in children: violation of the formation of teeth and bones, pathological changes in the lens of the eye, disorders of the nervous system, excitability, convulsions, poor blood clotting.

Diagnosis of hypocalcemia

Diagnosis of the condition is carried out on the basis of the patient's complaints and the laboratory determination of the element in the blood serum (the norm is 2.15 - 2.50 mmol / l).

Treatment - how to compensate for the lack of calcium

• Acute condition therapy hypocalcemia is carried out in a hospital, tk. this situation is life threatening.
• chronic deficiency macronutrient requires taking calcium supplements, vitamin D3 and other elements, normalizing the diet and eliminating behavioral factors and products that impair the absorption of Ca or contribute to its loss.

Therapeutic drugs are prescribed in such a way that the daily intake of the element is approximately 1.5-2 g. Vitamin D preparations are selected in an individual dosage, based on the needs of the body. The course of treatment, as a rule, is long and is set individually. The modern pharmaceutical industry produces combined preparations containing both calcium and vitamin D3 and other necessary pharmacologically active substances.

Calcium preparations

Pharmaceutical preparations are prescribed for the treatment and prevention of conditions and diseases associated with hypocalcemia, as well as to accelerate the healing of bone fractures. Features of calcium preparations:

• The composition should indicate the amount of elemental, pure calcium;
• Better digestibility is achieved when taken with food;
• Caffeine, carbonated drinks and alcohol significantly impair the absorption of the element;
• Poor digestibility is also characteristic when combined with antibiotics from the tetracycline group, laxatives, anti-inflammatory and anticonvulsants;
• Often calcium supplements cause side effects in the form of abdominal pain, nausea, constipation.
• Each drug has a number of strict contraindications (pregnancy, urolithiasis, tuberculosis, chronic renal failure, childhood, etc.).

All drugs from this category can be divided into 3 groups:

• Monopreparations containing a macronutrient in the form of a salt: calcium carbonate (40% of the element), calcium citrate (21%), calcium gluconate (9%), calcium lactate (13%), etc.
• Combined drugs, including calcium salts, vitamin D and other minerals. Vitamin D is involved in calcium metabolism, synthesis and maintenance of bone architectonics, therefore such dosage forms are more effective: Calcium D3 Nycomed, Calcemin, etc.
• Multivitamins. They contain several vitamins and minerals in prophylactic dosages and are intended for the prevention of hypocalcemia, and are also prescribed as an additional source of the element: Multi-tabs, Alphabet, etc. (calcium content per 1 tablet 150-200 mg).

Popular drugs

Calcium carbonate and Magnesium carbonate

Rennie 170 -250 rubles. (menthol, orange, mint). Contains calcium in bound systemic form, 680 mg calcium 80 mg magnesium hydroxycarbonate per 1 chewable tablet. It is used to eliminate the shortcomings of these elements, and also has an antacid effect. It is intended for use by adults and children over 12 years old - 2 tab. after eating, dissolving in the mouth (maximum 11 per day).

Calcium chloride

In 1 ml - 0.1 g of calcium chloride. A drug prescribed for hypocalcemia, diseases of the thyroid gland, blood vessels. Produced as a solution for intravenous administration in adults (15 ml 2-3 r per day) and children (5-10 ml 2 r per day), diluted with glucose or sodium chloride.

Calcium carbonate + Colecalciferol

Popular combined preparations that compensate for the deficiency of the element and improve its absorption. Under the action of the drug, the absorption of elements in the gastrointestinal tract is regulated, increased synthesis of parathyroid hormones is prevented, and bone resorption increases. For therapeutic purposes, the dosage is selected individually. From prophylactic:

• children 4-11 years old - 1 t 2 r per day
• children over 12 liters and adults - 2 tons 3 r per day.

Calcemin Advance

30 pcs. 440 rubles, 120 pieces 850-900 rubles. Calcium citrate + carbonate 500 mg, vitamin D3 5 mcg - a complex drug designed to eliminate calcium deficiency and prevent conditions in adults and children from 12 years old. Contains calcium, magnesium, zinc, copper, boron, cholecalciferol. It is taken 1 t 2 times a day.

Marine calcium

100 pieces. 100 rub. Available in several variations - with magnesium, zinc, selenium, vitamin C, iodine. It belongs to the category of dietary supplements and acts as an additional source of these elements during pregnancy, lactation and menopause in women, intensive growth in adolescents, etc.

During the entire period of treatment, it is necessary to control the level of serum calcium - every week during the first month, then the multiplicity decreases.

Eggshell from lack of calcium in the body

Many sources traditional medicine promote the consumption of eggshells as a natural source of calcium. Indeed, the egg shell is 90% calcium. But research recent years showed that the digestibility of the element from the shell is very low, even when used with lemon or something else. Therefore, it is not worth considering eggshells as an alternative to a balanced diet or therapeutic drugs.

Sources give the following recipe for preparing eggshells: thoroughly washing and removing a thin inner film from it, the shell is dried and ground into powder. Take half a teaspoon a day with meals, adding a couple of drops of lemon juice. The course is 1.5-2 months, once every six months.

Calcium for the elderly - myths and reality

As you know, the risk of developing osteoporosis increases many times in older people, and many, taking care of their health, increase the consumption of dairy products for sufficient calcium intake in the body. New Zealand scientists have questioned the need for a higher proportion of calcium to strengthen bones for people over 50 years old.

• Mark Bolland, along with a team of researchers from the University of Auckland, analyzed 2 studies that looked at the effect of calcium on bone density. One of them covered the age group over 50 (13,790 people). As it turned out, the constant intake of calcium supplements and foods with a high content of the element increased bone density by only 1-2%.
• Another study found a relationship between the incidence of bone fractures and calcium intake. More than 45,000 people participated in the survey. It turned out that regular intake of a macronutrient does not in any way reduce the likelihood of bone fracture.

Thus, the scientists concluded that there is no reason to take calcium supplements or switch to diets with a high content of the element in foods (calcium should be supplied with food in the daily requirement).

But sufficient physical activity, in particular, jumping for 2 minutes daily is a good preventive measure for osteoporosis for the elderly. But let's not forget that this is just one study concerning a specific group of people without taking into account comorbidities and characteristics of the body. If a doctor recommends taking calcium supplements for confirmed hypocalcemia or a tendency to hypocalcemia, his recommendations should be followed.

Prevention of hypocalcemia

Prevention of this pathological condition for healthy people who do not suffer from diseases that lead to Ca deficiency consists in a number of elementary things that everyone can do.

• Daily consumption of foods containing a sufficient amount of a macronutrient that can satisfy the daily need for it;
• The use of foods rich in vitamin D, which ensures the transformation of Ca in the body and its better absorption (sour milk, vegetable oils, eggs, seafood, fish liver, fish oil, oatmeal, greens);
• Vitamin D prophylaxis for children autumn-winter period(on the recommendation of a doctor);
• Sufficient location for sunlight during safe hours, excluding the period from 12 to 15.00, which ensures the synthesis of vitamin D in the human body;
• Periodic use of balanced vitamin-mineral complexes, but on the recommendation of a doctor and observing physiological dosages. Medical prevention hypocalcemia is especially relevant for pregnant, lactating and elderly women;
• Compliance with proper physical activity, feasible sports.

Foods containing calcium

A complete diet with a sufficient proportion of calcium is the best prevention of both hypocalcemia and diseases associated with a lack of a macronutrient. It is easy to calculate the proper consumption of certain products, knowing the daily rate and the amount of the element in 100 grams of the product. There is a lot of calcium in dairy products, however, with age, their digestibility worsens, so you should not rely only on this source of the element. Also, a large amount of calcium is found in vegetables, seafood, nuts.

Some features related to the absorption of calcium

• The digestibility of Ca from milk is only 30%;
• Products plant origin characterized by 50% macronutrient digestibility;
• The diet should be rich in foods containing vitamins D, C and magnesium;
• Nicotine, alcohol, coffee, soda (especially cola), sausages, smoked meats contribute to Ca leaching and impair its absorption;
• Salt also contributes to the removal of the macronutrient from the body and negatively affects the gastrointestinal mucosa, impairing absorption.
• The average daily intake of calcium for an adult should be 1000-1500 mg. This amount is due to the fact that not all of the calcium listed in the food list is absorbed by the body.

What foods contain calcium - table (amount of calcium - mg per 100 g of product)

Calcium in the body is an intracellular cation (Ca 2+), a macroelement, which in its quantity noticeably exceeds the content of many other chemical elements, providing a wide range of physiological functional tasks.

Calcium in the blood is only 1% of the total concentration of the element in the body. The bulk (up to 99%) is taken over by bones and tooth enamel, where calcium, along with phosphorus, is present in the composition of the mineral, hydroxyapatite - Ca 10 (PO 4) 6 (OH) 2.

The norm of calcium in the blood is from 2.0 to 2.8 mmol / l (according to a number of sources from 2.15 to 2.5 mmol / l). Ionized Ca is half as much - from 1.1 to 1.4 mmol / l. Every day (per day) through the kidneys of a person who does not notice any diseases, from 0.1 to 0.4 grams of this chemical element is excreted.

calcium in the blood

Calcium in the blood is an important laboratory indicator. And the reason for this is the number of tasks solved by this chemical element, because in the body it really performs many physiological functions:

• Takes part in muscle contraction;
• Along with “takes care” of the health of the nervous system (participates in signal transmission), as well as blood vessels and the heart (regulates heart rate);
• Activates the work of many enzymes, takes part in the metabolism of iron;
• Together with strengthens the skeletal system, provides strength to the teeth;
• Affects cell membranes, regulating their permeability;
• Without Ca ions, there is no reaction of blood coagulation and clot formation (prothrombin → thrombin);
• Activates the activity of certain enzymes and hormones;
• Normalizes the functional ability of individual endocrine glands, for example, the parathyroid gland;
• Influences the process of intercellular information exchange (cellular reception);
• Promotes better sleep, improves overall health.

However, it should be noted that calcium does all this subject to its normal content in the body. However, the tables will probably tell you better about the rate of calcium in the blood and its consumption depending on age:

The rate of calcium intake per day depends on age, gender and body condition:

Elevated plasma calcium creates a condition hypercalcemia, at which the content of phosphorus in the blood falls, and a low level leads to the development hypocalcemia accompanied by an increase in the concentration of phosphates. Both of those are bad.

The consequences arising from these states are reflected in the work of many vital systems, because this element has many functions. The reader will learn about the troubles that await a person with a decrease or increase in calcium a little later, after he gets acquainted with the mechanisms of Ca regulation in the body.

How is calcium levels regulated?

The concentration of calcium in the blood directly depends on its metabolism in the bones, absorption in the gastrointestinal tract and reabsorption in the kidneys. Other chemical elements (magnesium, phosphorus), as well as individual biologically active compounds (hormones of the adrenal cortex, thyroid and parathyroid glands, sex hormones, the active form of vitamin D 3), regulate the constancy of Ca in the body, but the most important of them are:

regulation of calcium in the body

1. Parathyroid hormone or parathormone, which is intensively synthesized by the parathyroid glands in conditions of an increased amount of phosphorus, and by its effect on bone tissue (destroys it), the gastrointestinal tract and kidneys, increases the content of the element in serum;
2. Calcitonin- its action is opposite to parathyroid hormone, but not antagonistic to it ( different points applications). Calcitonin reduces the level of Ca in plasma, moving it from the blood to the bone tissue;
3. Formed in the kidneys the active form of the vitaminD 3 or a hormone called calcitriol, performs the task of increasing the absorption of the element in the intestine.

It should be noted that calcium in the blood is located in the form of three forms that are in equilibrium (dynamic) with each other:

• Free or ionized calcium(calcium ions - Ca 2+) - it takes a share approaching 55 - 58%;
• protein-bound Ca, most often with albumin - it is about 35 - 38% in serum;
• Complexed calcium, it is about 10% in the blood and it stays there in the form of calcium salts - compounds of the element with low molecular weight anions (phosphate - Ca 3 (PO 4) 2, bicarbonate - Ca (HCO 3), citrate - Ca 3 (C 6 H 5 O 7) 2, lactate - 2(C 3 H 5 O 3) Ca).

Total Ca in blood serum is the total content of all its types: ionized + bound forms. Meanwhile, metabolic activity is characteristic only of ionized calcium y, which in the blood is slightly more (or slightly less) than half. And only this form (free Ca) can be used by the body for its physiological needs. But this does not mean that in the laboratory, in order to correctly assess calcium metabolism, it is necessary to analyze ionized calcium, which presents certain difficulties in transporting and storing blood samples.

In such cases, but subject to normal protein metabolism, it is enough to perform an easier and less laborious study - the determination of total calcium in the blood, which is a good indicator of the concentration of an ionized and associated element (≈55% - free Ca).

At the same time, with a reduced content (primarily of albumin), although there may be no signs of a decrease in the amount of Ca in plasma, it will be necessary to use a technique for measuring ionized calcium, since, being within the normal range, it takes care of maintaining the total the level of the element is normal and does not allow the development of hypocalcemia. In this case, only the content of bound Ca will be reduced - this point should be taken into account when deciphering a blood test.

Low levels of albumin in patients weighed down by a burden of chronic diseases (renal and heart pathology) is the most common cause decrease in serum Ca levels. In addition, the concentration of this element decreases with insufficient intake from food or during pregnancy - and in these two cases, albumin in the blood, as a rule, is also low.

Normal values ​​of total and free calcium in the blood, most likely, will indicate the absence of any pathological changes in calcium metabolism.

Causes of high calcium

An increase in the level of calcium (meaning the total content of the element in the blood) is called hypercalcemia. Among the reasons for the development of this condition, clinicians distinguish primarily two main ones. It:

1. Hyperparathyroidism, accompanied by an increase in the parathyroid glands as a result of the emergence of benign tumors in this region;
2. The development of malignant oncological processes, which form a state of hypercalcemia.

Tumor formations begin to actively secrete a substance that is similar in its biological properties to parathyroid hormone - this leads to damage to the bones and the release of the element into the bloodstream.

Of course, there are other causes of hypercalcemia, for example:

• Increasing the functional abilities of the thyroid gland (hyperthyroidism);
• Violation of the function of the adrenal cortex (increased secretion of adrenocorticotropic hormone (ACTH) - Itsenko-Cushing's disease, decreased synthesis of cortisol - Addison's disease) or the pituitary gland (excessive production of somatotropic hormone (STH) - acromegaly, gigantism);
• Sarcoidosis (Beck's disease) - although this pathology does not affect the bones so often, it can cause hypercalcemia;
• Tuberculous process affecting the skeletal system (extrapulmonary tbs);
• Forced immobility for a long time;
• Excessive intake of vitamin D (as a rule, this applies to children) in the body, which creates conditions for the absorption of Ca into the blood and prevents the removal of the element through the kidneys;
• Various hematological pathologies (lymphatic tissue diseases -, a malignant tumor from plasma cells -, neoplastic diseases of the hematopoietic system - including hemoblastoses - or true polycythemia);
• Destruction of bone tissue (osteolysis) in neoplastic processes of various origins;
• kidney transplant;
• Dehydration of the body (dehydration);
• Deforming ostosis (osteitis) or Paget's disease - the nature of the disease is not fully understood;
• Application dosage forms estrogen or vitamin D in inadequate doses (overdose);
• Chronic enterocolitis in advanced cases (stage 4).

When is calcium low?

The most common cause of a low content of an element in the blood - hypocalcemia, doctors call a decrease in the level of proteins and, first of all, albumin. In this case (as mentioned above), only the amount of bound Ca decreases, while ionized Ca does not leave the normal range and due to this, calcium metabolism continues to go on as usual (it is regulated by parathyroid hormone and calcitonin).

Other causes of hypocalcemia include:

1. Decreased functional abilities of the parathyroid glands (hypoparathyroidism) and production of parathyroid hormone into the bloodstream;
2. Inadvertent removal of the parathyroid glands during surgery on thyroid gland or the synthesis of parathyroid hormone is reduced as a result of other circumstances (surgery due to aplasia of the parathyroid glands or autoimmunization);
3. Vitamin D deficiency;
4. CRF (chronic renal failure) and other kidney diseases (nephritis);
5. Rickets and rachitogenic tetany (spasmophilia) in children;
6. Magnesium (Mg) deficiency in the body (hypomagnesemia);
7. Congenital lack of response to the effects of parathyroid hormone, immunity to its influence (parathyroid hormone in such a situation loses its ability to provide the proper effect);
8. Insufficient intake of Ca with food;
9. Increased phosphate levels in the blood;
10. diarrhea
11. Cirrhosis of the liver;
12. Osteoblastic metastases, which take all the calcium, which then ensures the growth of the tumor in the bones;
13. Osteomalacia (insufficient mineralization of the bones and their softening as a result of this);
14. Hyperplasia (excessive tissue growth) of the adrenal glands (more often the cortex than the medulla);
15. The effect of drugs intended for the treatment of epilepsy;
16. Acute alkalosis;
17. Blood transfusions large volumes of blood prepared with a preservative that contains citrate (the latter binds calcium ions in plasma);
18. Spicy inflammatory process, localized in the pancreas (acute pancreatitis), sprue (a disease of the small intestine that disrupts the absorption of food), alcoholism - all these pathological conditions prevent the normal production of enzymes and substrates, which makes it impossible for the absorption in the gastrointestinal tract of substances that are so necessary to ensure certain types of metabolism .

Symptoms that make you think about violations

This blood test is also prescribed to healthy people in order to preliminary determine the state of calcium metabolism, for example, during a routine medical examination. However, here we would like to remind the reader once again that we are talking about the level of calcium in the blood. What happens in the bones - one can only guess and guess.

Often such a test is used for diagnostic purposes. Say, how not to conduct a laboratory study, if the symptoms of pathological changes in the body declare themselves?

Here, for example, with increased calcium in the blood (hypercalcemia), patients note that:

• Lost appetite;
• Several times a day nausea sets in, sometimes it comes to vomiting;
• There were problems with the stool (constipation);
• In the abdomen - discomfort and pain;
• You need to get up at night, because the frequent urge to urinate does not allow you to sleep peacefully;
• Always thirsty;
• Bones hurt, headaches often torment;
• The body quickly gets tired, even the minimum load turns into weakness and a sharp decrease in efficiency;
• Life becomes gray, nothing pleases and does not interest (apathy).

You can think about a decrease in the content of Ca in the blood serum - hypocalcemia, if there are such signs of ill health:

1. Cramping and pain in the abdomen;
2. Trembling of the fingers of the upper limbs;
3. Tingling, numbness of the face (around the lips), spasms of facial muscles;
4. Violation of the heart rhythm;
5. Painful muscle contractions, especially in the hands and feet (carpopedal spasm).

And even if a person does not have any symptoms indicating a change in calcium metabolism, but the results obtained were far from normal, then, to dispel all doubts, the patient is prescribed additional tests:

• Ionized Ca;
• The content of the element in the urine;
• The amount of phosphorus, since its metabolism is inextricably linked with calcium metabolism;
• Magnesium concentration;
• Vitamin D;
• Parathyroid hormone level.

In other cases, the quantitative values ​​of these substances may be less important than their ratio, which may reveal the cause of the abnormal Ca content in the blood (either it is not enough in food, or it is excessively excreted in the urine).

Purposefully determine the level of calcium in the blood of patients with kidney problems (ARF and CRF, tumor, kidney transplant), multiple myeloma or ECG changes (shortened ST segment), as well as in the diagnosis and treatment of malignant processes localized in the thyroid and mammary glands, lungs, brain, throat.

What is useful to know for everyone who is going to take a test for Ca

In newborns after 4 days of life, a physiological increase in calcium in the blood is sometimes observed, which, by the way, also happens in premature babies. In addition, some adults respond with an increase in the level of this chemical element in the serum and the development of hypercalcemia on therapy with individual drugs. These drugs include:

1. Antacids;
2. Pharmaceutical forms of hormones (androgens, progesterone, parathyroid hormone);
3. Vitamins A, D 2 (ergocalciferol), D 3;
4. An estrogen antagonist - tamoxifen;
5. Preparations containing lithium salts.

Other drugs, on the contrary, can reduce the concentration of calcium in the plasma and create a state of hypocalcemia:

• Calcitonin;
• Gentamicin;
• anticonvulsant medicines;
• Glucocorticosteroids;
• magnesium salts;
• Laxatives.

In addition, other factors can affect the final values ​​of the study:

1. Hemolyzed serum (you can’t work with it, so the blood will have to be retaken);
2. Falsely high test results due to dehydration or high levels of plasma proteins;
3. False-low results of the analysis due to hypervolemia (blood is highly diluted), which could be created by large volumes of isotonic solution (0.9% NaCl) injected into the vein.

And here's something else that does not hurt people who are interested in calcium metabolism to know:

• In children who have just been born, and especially in those who were born prematurely and with low weight, blood is taken every day for the content of ionized calcium. This is done in order not to miss hypocalcemia, because it can quickly form and not show any symptoms if the baby's parathyroid glands have not had time to complete their development;
• The content of Ca in serum and urine cannot be taken as evidence of the total concentration of the element in bone tissue. To determine its level in the bones, one should resort to other research methods - analysis of bone mineral density (densitometry);
• Ca levels in the blood tend to be higher in childhood, while they decrease during pregnancy and in the elderly;
• The concentration of the total amount of the element (free + bound) in plasma increases if the content of albumin increases and falls down if the level of this protein decreases. The concentration of albumin has absolutely no effect on the amount of ionized calcium - the free form (Ca ions) remains unchanged.

When going for analysis, the patient must remember that one should refrain from eating for half a day (12 hours) before the test, and also avoid heavy physical exertion half an hour before the study, do not be nervous and do not smoke.

When One Technique Isn't Enough

When there are changes in the concentration of the described chemical element in the blood serum and there are signs of impaired Ca metabolism, the study of the activity of calcium ions with the help of special ion-selective electrodes is of particular importance. However, it should be noted that the level of ionized Ca is usually measured at strict values ​​(pH = 7.40).

Calcium can also be determined in the urine. This analysis will show how much or little the element is excreted through the kidneys. Or its excretion is within normal limits. The amount of calcium in the urine is examined if abnormal Ca concentrations from the norm were initially detected in the blood.

Ionized Ca is the active form of this element. In the human body, it is contained in the form of a positively charged Ca2+ ion and is responsible for many vital processes, from the point of view of physiology. An important feature of ionized calcium is its ability to be metabolically active.

In addition to its active (free) form, calcium in the blood can be associated with negatively charged ions in the form of lactates, phosphates, bicarbonates and other compounds, or with albumin proteins in the blood serum. The sum of all three forms of calcium in the body is called total calcium.

Calcium in the blood can be in three forms in the following ratio:

• 55 - 58% falls on ionized calcium;
• 35 - 38% due to albumins;
• 10% in complex form with low molecular weight anions.

The active element accounts for more than half of the percent, which shows the importance of the analysis for ionized calcium.

The rate of calcium in the blood in adults is 2.0 - 2.8 mmol / l, the rate of ionized - 1.1 - 1.4 mmol / l.

Normal blood calcium is also determined by age:

Ca and pregnancy

The rate of calcium in the blood in women is 2.20 - 2.50 mmol / l. One of the reasons for the physiological deficiency of the element and deviation from the norm in women is pregnancy. Women in interesting position it is necessary to increase the daily dose of Ca intake, as it affects the skeletal system of the unborn child. Also, high doses of Ca are needed during the period breastfeeding.

Ca functions

The main function is the regulation of the activity of myocytes, that is, cells of the muscle tissue of the heart, strengthening of bone tissue, as well as ensuring the contractile ability of striated muscles.

Other biochemical processes in which Ca is involved are:

• Transmission of an electrical impulse along a nerve fiber;
• Regulation of the hemostasis system;
• Regulation of cell wall permeability;
• Regulation of enzyme synthesis;
• Regulation of hormone synthesis by endocrine glands;
• Regulation of normal values ​​of iron in blood serum.

All of the above processes proceed at the proper level only under the condition of a normal content of ionized calcium in the blood and total calcium in the bones.

Ca exchange in the body

Ca homeostasis depends on how it is absorbed in the intestine, on the exchange of minerals in bone tissue, and on reabsorption in the kidneys. There are three main biologically active substances that regulate calcium metabolism:

1. Parathyroid hormone, which is produced by the parathyroid glands in response to an increase in phosphorus, which leads to an increase in calcium levels;
2. Calcitonin, produced by the thyroid gland and reduces the level of calcium in the blood, due to its transport to the bones;
3. Calcitriol, or activated vitamin D3, which promotes Ca absorption in the gastrointestinal tract.

Symptoms of Ca metabolism disorders

There are two types of abnormal calcium levels in the body - hypocalcemia, that is, a low content, and hypercalcemia, if calcium in the blood is elevated. Since it is almost impossible to exceed the normal level of calcium in the average person (provided there is no serious pathology), it is hypocalcemia that is most common.

hypocalcemia

The Ca-deficient patient presents with general complaints of headache, frequent episodes of dizziness, weakness, lethargy, dry skin, hair loss.

A characteristic symptom of a violation of bone tissue metabolism is caries due to thinning of tooth enamel, brittle nails, and curvature of the nail plate. With advanced hypocalcemia, osteoporosis and pathological fractures may occur. Ca deficiency in children is manifested by growth retardation, bone deformity, and posture disorders.

On the part of the muscular apparatus, there is an increase in muscle tone, periodically occurring convulsions after physical activity, pathological reflexes.

From the side of the heart and the hemostasis system, tachycardia, arrhythmia are noted, the time to stop bleeding is increased, in severe cases, hypocalcemia can lead to coronary heart disease.

Hypercalcemia

If ionized calcium is elevated, this is manifested by shortness of breath, nausea, vomiting, disruption of the heart due to the deposition of Ca compounds, decreased muscle tone, increased blood clotting with the risk of blood clots and emboli.

The reasons

hypocalcemia

Most often, hypoalbuminemia, that is, a decrease in the level of blood albumin, is the basis of a low calcium level in the blood.

In addition, the reasons may be:

• Hypoparathyroidism;
• Vitamin D deficiency;
• renal pathology;
• Rickets;
• Magnesium deficiency;
• Cirrhosis of the liver;
• Hyperplasia of the adrenal glands;
• Acute pancreatitis and others.

Hypercalcemia

The most common causes of elevated calcium levels in the blood are hyperparathyroidism and malignant neoplasms. The first leads to hypercalcemia directly due to an increase in the production of parathyroid hormone, and MNs produce and release into the blood a substance that mimics the action of parathyroid hormone.

In addition, the reasons may be:

• Hyperthyroidism;
• Endocrine pathologies (Addison's disease, acromegaly);
• Sarcoidosis;
• Tuberculosis;
• Increased content of vitamin D;
• Pathology of the blood system (leukemia, erythremia);
• osteolysis;
• dehydration and others.

Diagnostics

Diagnosis is based on the collection of patient complaints, instrumental and laboratory data. To confirm the altered calcium metabolism, the doctor prescribes the following tests:

• Analysis for total calcium;
• Analysis for calcium ionized;
• Blood chemistry;
• Urinalysis for calcium content;
• Phosphorus content analysis;
• Magnesium analysis;
• Vitamin D analysis;
• Parathyroid hormone level;

When evaluating the results of blood tests for calcium and other elements, it is important to analyze both quantitative indicators relative to the norm and the ratio of elements involved in calcium metabolism. In a biochemical blood test, serum albumin proteins are primarily evaluated.

What should a patient know about taking a blood test for ionized calcium?

There are a number of rules: in order to prepare for the analysis for ionized calcium and obtain reliable data, the patient must exclude food intake twelve hours before the analysis, as well as avoid stressful situations, physical exertion, smoking less than half an hour before the analysis.

A number of medications can change the normal level of ionized calcium in the blood. Drugs that cause hypercalcemia include:

• Antacids;
• Preparations analogues of hormones;
• "Tamoxifen".

Drugs that cause hypocalcemia:

• "Calcitonin";
• "Gentamicin";
• Anticonvulsant drugs;
• magnesium salts;
• Laxative LP.

Treatment and prevention

The norm of calcium consumed per day with food is 800 - 1200 mg. Pregnant women are recommended to consume at least 1000 mg per day.

What to do if, according to the results of a blood test for calcium, hypocalcemia is diagnosed? First of all, in order to prevent hypocalcemia, you should change your diet and follow a diet. Ca-rich foods should be eaten daily.

On the recommendation of a doctor, you can take Ca preparations, combining them with vitamins of groups C and D, which increase the absorption of calcium in the body, as well as with magnesium preparations. Vitamin D ensures better absorption of the element by the intestines, participates in the biochemistry of Ca–P metabolism.

Calcium is one of the most important minerals present in the human body. With the appearance of deviations in its concentration in internal environments, many pathological conditions arise. Not only a decrease in its concentration (hypocalcemia), but also an increase (hypercalcemia) is dangerous. So, what to do if calcium in the blood is elevated, what does it mean, what is dangerous, what are the causes of this condition and prevention.

biological functions

Calcium affects almost all spheres of life of any living organism. What this element does not affect, from the formation of the bone structure of the human skeleton, to the processes of biosynthesis of most hormones and biological fluids. Below I will briefly mention the most important biological functions of this mineral.

Calcium is the regulator of all electrical processes. Due to this element of the periodic system, the process of depolarization of the biological membrane occurs, which leads to a potential difference and the appearance of an electrical impulse.

Electrical activity is most important for the nervous, cardiovascular and musculoskeletal systems. However, smooth muscle fibers located in many hollow organs are controlled by similar forces.

Calcium is absolutely necessary for the processes of blood clotting. Without it, most of the cascade of biochemical reactions leading to the formation of a fibrin thrombus will simply not be effective.

Calcium inhibits inflammation by reducing the permeability of the vascular wall. In inflammatory pathology, the body is extremely susceptible to a deficiency of this substance.

How does hypercalcemia manifest itself?

Of course, only a biochemical blood test can confirm or refute the presence of hypercalcemia. However, such a condition can be suspected already at the time of collecting patient complaints.

An elevated level of calcium in the blood does not have any specific manifestations. Patients may complain general: feeling unwell, fatigue, recurrent abdominal pain, nausea, rare vomiting, loss of appetite, constipation, rumbling in the abdomen, heart rhythm disturbances (palpitations), weight loss and a number of other symptoms.

When conducting a biochemical blood test, an increased calcium content is determined, more than 2.5 mmol per liter, which eloquently indicates the presence of problems in mineral metabolism.

If hypercalcemia reaches very high values, then the severity of the condition is greatly aggravated. The following symptoms appear: confusion, hallucinations, coma, severe weakness, frequent mood swings, vomiting, and signs of dehydration.

Increased calcium in the blood - what are the reasons for this?

The reasons that can lead to the development of hypercalcemia are very extensive, but most often they are not associated with the peculiarities of alimentary (food) behavior. Experts say that in 80 percent of cases, such conditions are provoked by hyperparathyroidism.

Hyperparathyroidism is an endocrine pathology, the main pathogenetic mechanism of which is the increased synthesis of parathyroid hormone (parathyroid hormone). Most often, this pathology occurs in women in the postmenopausal period.

Hyperparathyroidism is always accompanied by leaching of minerals from the bones, which leads to the appearance of pathological changes in the bone structure, and a sharp increase in the level of calcium in the patient's blood.

The remaining 20 percent account for more than 2 dozen conditions that can be accompanied by an increase in the level of calcium in the blood. These are infectious diseases, in particular tuberculosis, prolonged immobilization as a result of injuries, thyroid pathology, blood diseases, malignant neoplasms, and so on.

They revealed elevated calcium in the blood - what is the diagnosis dangerous for?

Hypercalcemia, especially prolonged, is dangerous for its consequences, among which, first of all, it is necessary to mention urolithiasis. An excess of the mineral is excreted in the urine, which contributes to an increase in the concentration of salts in this biological fluid and the appearance of calculi (stones).

Secondly, an excess of calcium is deposited in many tissues, but primarily in the vessels, which leads to a significant decrease in their elasticity and increased fragility. This is true mainly in relation to small arteries and veins. Such conditions are accompanied by increased bleeding and frequent fluctuations in blood pressure.

Hypercalcemia leads to damage to the central nervous system. In these patients, there is a decrease mental capacity, they often suffer from headaches and get tired from the slightest physical exertion. Patients may complain of difficulty falling asleep.

If calcium is elevated in the blood - what is the treatment for hypercalcemia?

When hypercalcemia is detected, patients are shown diet food. All foods containing an increased amount of calcium should be excluded from the diet: milk, cheese, cottage cheese, yogurt and some others.

To reduce the risk of stone formation, diuretic drugs are indicated in combination with increased fluid intake. To enhance the effect, you can supplement treatment procedures with infusions and decoctions of medicinal herbs.

Hypercalcemia is almost always secondary and occurs against the background of other diseases. In addition to the normalization of calcium levels, special attention should be paid to the treatment of primary pathology.

In hyperparathyroidism, the appointment of calcitonin is indicated, which enhances the processes of removing calcium from the body. AT severe cases surgical treatment is indicated, the purpose of which is to remove part of the parenchyma of the parathyroid glands.

Conclusion

Increased calcium in the body is a potentially dangerous disease, the treatment of which should be handled by an experienced specialist. If the complaints listed above appear, it is recommended to go to the hospital and undergo a full course of examination.

Calcium is a trace element, which, in terms of its content in the body, significantly exceeds the quantitative composition of other chemical elements. Calcium (Ca 2+) solves many problems, providing important functions of the human body.

Blood calcium contains no more than 1% of the total amount of calcium in the body. The remaining 99% are in the teeth and skeleton, in which calcium is represented by the mineral Ca 10 (PO 4) 6 (OH) 2 and is combined with phosphorus.

Normal blood calcium levels range from 2.0-2.8 mmol/L. According to some reports, the limits of the norm can be 2.15-2.5 mmol / l.

1.1-1.4 mmol / l is the normal level of ionized calcium in the blood.

0.1-0.4 g of calcium every 24 hours is excreted from the body by the kidneys of a healthy person along with urine.

Determining the level of calcium in the blood is often required to diagnose various diseases.

After all, in the body it is responsible for many important functions:

Without calcium, normal muscle contractility is impossible.

Calcium is involved in the transmission of nerve impulses, regulates heart rhythms. These functions are controlled by calcium together with magnesium.

Calcium stimulates the work of many enzymes, is involved in the metabolic processes of iron.

Teeth and bones would not have their strength if they did not have enough calcium and phosphorus.

Calcium affects cell permeability.

Calcium is involved in the formation of a thrombotic clot at the stage of converting prothrombin to thrombin. If the trace element is not enough, then normal blood clotting is impossible.

Calcium activates part of the hormones in the body.

Calcium takes part in the normal functioning of the endocrine glands. So, without it, the parathyroid gland cannot fully function.

Calcium is involved in the processes of cell reception, in which cells exchange information with each other.

A person cannot be healthy if there is not enough calcium in his body. Without this trace element, high-quality and full sleep is impossible.

Normal values ​​of calcium in the body depend on the age of the person:

1.90-2.60 - a newborn child in the first 10 days of life.

2.25-2.75 - a child older than 10 days and under the age of 2 years.

2.20-2.70 - a child 2-4 years old.

2.10-2.55 - teenager 12-18 years old.

2.15-2.50 - an adult 18-60 years old.

2,20 -2,55 – old man 60-90 years old.

2.05-2.40 - people over 90 years old.

Depending on the age and gender of a person, the daily intake of calcium will differ.

The dosage is given in milligrams:

200 - for children under 6 months.

400 - for children from six months to a year.

600 - for children 1-4 years old.

1000 - for children 4-11 years old.

1200 - for teenagers 11-17 years old.

1200 - for all adults.

1200 - for men 50-70 years old.

1400 - for women 50-70 years old.

1300 - for people over 70 years old.

1500 - for women who are expecting a baby or breastfeeding mothers.

It should not be assumed that a large amount of calcium in the body is beneficial to health. If its plasma concentration exceeds allowed values, then this leads to a drop in the level of phosphorus. If there is little calcium in the blood, then the amount of phosphates in it will begin to increase. Both of these conditions are pathological and entail violations in the most important functions of the body.

What determines the level of calcium in the blood?

The level of calcium in the blood has a direct relationship with its exchange in the bones of the skeleton, with the quality of its absorption in the intestines and reabsorption by the kidneys. Other trace elements, primarily magnesium and phosphorus, are responsible for the balance of calcium in the body. Also able to increase or decrease the level of calcium in the blood are sex hormones, hormones of the endocrine glands, adrenal glands, as well as the active form of vitamin D3.

So, the following components influence the level of calcium in the blood more strongly than others:

Parathyroid hormone (parathormone). It is produced by the parathyroid glands. With its excessive release, as well as against the background of an increased content of phosphorus in the blood, the processes of inhibition of bone tissue formation will be launched in the body. Parathyroid hormone leads to the fact that the level of calcium in the blood rises, and in the bones it becomes less.

Calcitonin, on the contrary, reduces the level of calcium in the blood, transporting it to the bone tissue.

Vitamin D3, which is produced in the active form by the kidneys, can lead to an increase in the level of calcium in the blood, as it enhances the absorption of this trace element in the intestine.

Calcium can be present in the blood in several forms:

Calcium ions - CA 2+. This form of calcium is called free or ionized. Of the total amount of calcium, the share of the ionized trace element accounts for about 55-58%.

Calcium, which is in conjunction with protein fractions. It accounts for about 35-38%.

Calcium salts, which account for about 10%. Calcium present in the blood in this form is called complexed. It can act in combination with phosphates - Ca 3 (PO 4) 2, citrates - Ca 3 (C 6 H 5 O 7) 2, lactates - 2 (C 3 H 5 O 3) * Ca) and bicarbonates - Ca (HCO 3).

If doctors talk about an increase in the level of calcium in the blood, then it means that all its forms are elevated. Only ionized calcium exhibits metabolic activity. It is he who is most involved in all needs. human body. At the same time, for the diagnosis of various conditions, it is not required to determine the amount of ionized calcium. This study is highly specialized. To obtain adequate data, you can set the total level of this trace element in the blood.

If the concentration of protein in the blood is lowered, then the analysis may show a normal level of calcium. To detect its real values, it will be necessary to apply a technique that is aimed at counting the ionized form of the microelement, since it is it that replaces the complexed form of calcium. To identify such a deficiency, a more thorough study is required.

If a person with chronic diseases has a reduced level of protein in the blood, this leads to the development of calcium deficiency in the serum. Most often, this situation is observed in lesions of the kidneys and liver. The level of this trace element also decreases, provided that a person receives less of it with food. Women who are carrying a child may experience a drop in calcium levels, but the concentration will always be reduced.

Causes of low calcium levels in the blood

Hypocalcemia is the scientific name for a condition characterized by low levels of calcium in the blood. Most often, its fall is caused by a decrease in the level of albumin (a protein component of the blood). In this case, there is a deficiency of only protein-bound calcium, and ionized calcium will remain within the normal range.

Other causes that can lead to hypocalcemia:

Failure of the parathyroid glands, the ingress of parathyroid hormone into the blood.

The absence of parathyroid glands as a result of the operation.

Chronic renal failure, nephritis.

Spasmophilia and rickets in a child.

Acute deficiency of magnesium in the human body.

Immunity of the body to the effects of parathyroid hormone, due to congenital developmental anomalies.

High levels of phosphate in the blood.

Serious liver damage (cirrhosis).

The presence of osteoblastic metastases in the body, which require a lot of calcium to continue their pathological growth.

Hyperplastic changes in the tissue of the adrenal glands.

Reception medicines for treatment.

Transfusion of impressive volumes of blood, which contains citrate.

Alkalosis in the acute phase.

Diseases such as: alcoholism, acute course,. They are combined into one group, since each of them does not allow calcium to be normally absorbed into the blood from the gastrointestinal tract.

Symptoms of low and high calcium levels in the blood

The level of calcium in the blood is determined not only in the presence of any pathologies, but also during the passage of a medical examination absolutely a healthy person. However, this study cannot reflect the exact state of the bone tissue.

The following symptoms will indicate a high level of calcium in the blood:

Complete or partial lack of appetite.

Nausea, which may be accompanied by vomiting.

Tendency to constipation.

Abdominal pain.

Frequent night trips to the toilet to empty the bladder.

Constant thirst.

Pain in the bones.

Increased fatigue.

Spasms of the muscles of the feet and hands.

If a person does not have signs indicating a deficiency or excess of calcium, but the analysis indicates the opposite fact, then a comprehensive examination is necessary.

For this, diagnostic measures such as:

Determination of the level of ionized calcium in the blood.

Determination of the level of calcium in the blood.

Determination of the level of phosphorus in the blood.

Determination of the level of magnesium in the blood.

Determination of the level of vitamin D in the blood.

Determination of the level of parathyroid hormone.

Sometimes, in order to diagnose a particular disease, it is required to find out the ratio of calcium in the blood in relation to other substances. For example, such studies make it possible to determine the excessive excretion of calcium in the urine, or its insufficient intake with food.