Antipyretics for children are prescribed by a pediatrician. But there are emergency situations with fever when the child needs to be given medicine immediately. Then the parents take responsibility and use antipyretic drugs. What is allowed to be given to infants? How can you lower the temperature in older children? What medications are the safest?
Allows you to determine the quantitative and qualitative composition, which in turn indicates the state of human health and the presence of any problems. In addition to leukocytes and platelets, red blood cells are subject to careful examination. These red blood cells perform a transport function, delivering nutrients and oxygen to all cells and organs. One of the indicators of their level is the erythrocyte index, designated MCV. This index allows you to estimate the number and size of red blood cells, which in turn is associated with general condition body. What else does MCV indicate in a blood test, what it is and what normal indicators are established, we will find out further.
The red blood cell index (MCV) shows the total volume of red blood cells contained in the blood. U healthy person this coefficient is a constant value, the change of which entails pathological changes in organism.
Highlight two main indicators that determine the need for analysis:
- Determination of water-salt balance disorders (for intestinal infections, acute respiratory infections and acute respiratory viral infections).
- Diagnosis of anemia (iron deficiency).
Also indications for conducting research may include manifestations such as:
- hormonal imbalances;
- metabolic disease;
- obesity;
- diabetes;
- low immunity.
Most often, MCV analysis reveals various forms of anemia:
- normochromic anemia - develops with bone marrow pathologies that are caused by the presence chronic diseases;
- macrocytic anemia - a pathological increase in red blood cells in size due to a lack of B vitamins and folic acid;
- microcytic anemia - develops as a result of acute iron deficiency, resulting in decreased synthesis of polypeptide chains.
A healthy person has a normal MCV of 80 to 100 femtoliters. This indicator is a nomrocyte, which means full compliance with the established norm. An excess of more than 100 femtoliters is a macrocyte, and a decrease of less than 80 is a microcyte.
Units of measurement and calculation
The average volume of a red blood cell is calculated in femtoliters or cubic micrometers. This erythrocyte index is determined using a mathematical formula that displays the ratio of hematocrit as a percentage to the total number of erythrocytes, after which the resulting value is multiplied by 1012 liters.
How is the analysis carried out?
In medical practice, MCV can be included either in a general blood test or performed without taking into account other blood fractions. The analysis will require blood from a finger or vein, taken in accordance with all the rules:
- the patient does not eat or drink 3-5 hours before blood sampling;
- women do not menstruate;
- the person feels satisfactory (no coma or cardiac shock).
A smear is prepared from the obtained blood, which is then examined under a microscope, highlighting the necessary indicators. Next, the indicators are entered into the formula, obtaining the desired value.
Decoding the results
After the analysis has been carried out, the patient is given a sheet that contains numerical indicators. The transcript can be contained either in the analysis sheet itself or done orally by the attending physician.
Normal indicators associated with a person's age:
- newborns – 100-140 fl;
- first year of life - 75-110 fl;
- 2-5 years – 75-95 fl;
- 5-10 years – 70-85 fl;
- 10-18 years – 80-95 fl.
Typically, the transcript is presented in the form of a table, which indicates the name of the research parameter, its numerical indicator, norm, and degree of deviation. This allows you to compare clinical manifestations diseases with their course at the micro level. The average volume of erythrocytes has important clinical significance, since it is interrelated with other blood parameters.
Increased values
If the analysis showed that the average volume of red blood cells is higher than normal, this indicates the development of a pathological condition such as macrocytic anemia.
She may accompany the course of the following diseases.
MCV (mean corpuscular volume) is one of the erythrocyte indices that shows the average volume of erythrocytes. This indicator can characterize the entire population of red blood cells in the blood. The calculated measure denotes the average volume occupied by one red blood cell. The value of this index is calculated by the formula: hematocrit as a percentage, multiplied by 10 and divided by the total number of red blood cells in the blood. Most laboratories measure MCV in cubic microns (µm2) or femtoliters (fl).
Changes in the erythrocyte composition of blood are one of the main laboratory criteria in the diagnosis of anemia, therefore, calculation of the average volume of erythrocytes in combination with other indicators of a clinical blood test is used for differential diagnosis, monitoring and evaluation of the effectiveness of treatment of anemia and diseases of the hematopoietic system, and determination of water-electrolyte balance disorders.
MCV in a blood test is calculated automatically - using a hematology analyzer, which determines the average volume of all measured red blood cells.
Red blood cells and their function in the body
Erythrocytes are red blood cells containing hemoglobin. Their main function is the transport of oxygen and carbon monoxide between the lungs and the tissues of other organs. In addition, red blood cells participate in reactions immune system, play a significant role in maintaining the acid-base balance, serving as a means of transport of nutrients (glucose, amino acids, salts, fatty acids) and breakdown products (uric acid, urea, ammonia, creatine).
Red blood cells are produced in the bone marrow. Their life cycle is 120 days, after its end the red blood cells are metabolized by the cells of the liver, spleen and bone marrow. They are replaced by young forms of red blood cells called reticulocytes. Before entering the microvasculature, cells go through several stages of development, during which their shape, size and chemical composition. For normal synthesis of red blood cells, a sufficient supply of vitamin B12, iron and folic acid is necessary.
Mature erythrocytes are anucleate cells that have the shape of biconcave discs, which allows them to penetrate into the narrowest and curved areas of the vascular bed. Due to the plasticity of red blood cells, the viscosity of blood in small capillaries is much less than in large ones.
The average diameter of a red blood cell in an adult is between 6.8 and 7.5 microns. Red blood cells with a diameter of less than 6.8 microns are called microcytes, and a condition in which the size of peripheral blood red blood cells is significantly smaller than normal means the presence of microcytosis. The presence in the blood of abnormally large red blood cells (macrocytes) with a diameter of more than 8 microns allows us to suspect macrocytosis in the patient.
Determination of the erythrocyte index is performed as part of general analysis blood, however, it can also be prescribed as a separate study.
The average volume of erythrocytes has diagnostic value in assessing micro- and macrocytosis; it is used in calculating the average content and concentration of hemoglobin in erythrocytes.
Normal MCV values
The normal MCV indicator in a blood test varies depending on age: in newborns it is maximum, in children in the first days and months of life its range is slightly wider than in adults, after a year the indicator decreases, and by the age of 18 it is fixed at a level of 80 to 100 fl. This means that with age, the average volume of red blood cells becomes lower. In men and women, the MCV norm and the interpretation of the blood test will also be different. In addition, the norms of blood parameters may vary depending on the determination method, laboratory, and units of measurement.
Normal MCV values depending on gender and age
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Girls – up to 128 fl Boys – up to 128 fl |
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Girls – up to 100 fl Boys – up to 100 fl |
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From 1 week to 1 year |
Girls – 77–79 fl Boys – 77–79 fl |
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Girls – 72–89 fl Boys – 70–90 fl |
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Girls – 76–90 fl Boys – 76–89 fl |
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Girls – 76–91 fl Boys – 76–81 fl |
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Girls – 79–93 fl Boys – 79–92 fl |
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Women – 82–96 fl Men – 81–93 fl |
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Women – 91–98 fl Men – 80–93 fl |
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Women – 80–100 fl Men 81–94 fl |
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Women – 82–99 fl Men – 82–94 fl |
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Women 80–100 fl Men – 81–100 fl |
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65 years and older |
Women – 80–99 fl Men – 78–103 fl |
An increase or decrease in the MCV indicator in a general blood test may indicate various diseases and pathological conditions, for example, an imbalance of water-salt balance: when the average volume of erythrocytes decreases, the disturbances are hypertonic in nature, and when they increase, they are hypotonic.
The average volume of red blood cells often decreases during pregnancy in women experiencing iron deficiency.
Reasons for increasing MCV
An increase in MCV in the blood may indicate a lack of vitamin B12, a lack of folic acid, the development of hyperchromic or macrocytic anemia, myelodysplastic syndrome, pathologies of the liver, bone marrow, renal failure, myxedema, hypothyroidism. The average red blood cell volume may be increased in case of methanol poisoning, abuse alcoholic drinks, smoking, taking certain medications.
Falsely elevated mean red blood cell volume can occur with hyperglycemia and diabetic ketoacidosis, cold agglutination of red blood cells.
MCV in blood test is reduced
The MCV index may be lowered in the case of microcytic anemia (iron deficiency, sideroblastic), hypochromic anemia with a lack of hemoglobin, thalassemia, kidney diseases, increasing the level of erythropoietin, hypertensive dehydration, blood loss, conditions accompanied by impaired formation or increased destruction of red blood cells, liver diseases associated with tissue changes, erythremia, hypothyroidism, cancer and autoimmune diseases. The average volume of red blood cells often decreases during pregnancy in women experiencing iron deficiency. Reason reduced rate may be lead poisoning, mechanical hemolysis, the presence of giant platelets.
To confirm or refute the diagnosis, additional research: biochemical blood test, determination of hormone levels, identification of tumor markers, immunological tests, ultrasound and others.
How is the MCV blood test performed?
The determination of the erythrocyte index is performed as part of a general blood test, but can also be prescribed as a separate study.
The MCV index value is calculated using the formula: hematocrit as a percentage, multiplied by 10 and divided by the total number of red blood cells in the blood.
Blood is drawn on an empty stomach, after an overnight period of fasting for at least eight, and preferably ten to twelve hours. On the eve of the analysis, it is recommended to refrain from excessive physical and psycho-emotional stress and to exclude physiotherapeutic procedures.
MCV in a blood test is calculated automatically - using a hematology analyzer, which determines the average volume of all measured red blood cells. The manual calculation method, in which the laboratory assistant himself counts the cells and makes calculations using a formula, is rarely used.
Video from YouTube on the topic of the article:
When making a diagnosis related to diseases of the circulatory system, it is not always sufficient to determine the quantitative content of red blood cells blood cells ec) and blood hemoglobin.
To obtain a detailed picture of the composition of the blood, the average volume of red blood cells is measured - a more important and detailed hemolytic analyzer, characterizing the formed elements not from a quantitative, but from a qualitative point of view.
It is determined by the ratio of the total volume of red blood cells contained in a portion of blood to their number.
The result allows you to determine the average volume of one red blood cell, which may be normal, or may be significantly lower or higher than normal.
Any deviation allows, in combination with other erythrocyte indices, to assume the reasons leading to this and make a correct diagnosis.
This analysis is usually denoted by the abbreviation MCV, which translated into Russian means average (Mean) corpuscular (Corpuscular) volume (Volume).
The units of measurement accepted in most laboratories are femtoliter (fl) or cubic micrometer (µm 3). It should be borne in mind that for some diseases this analysis is not reliable.
Normal limits by age category
The indicator is called normal if the average volume of red blood cells is in the range of no less than 80 and no more than 100 femtoliters. In newborns, the normal range is somewhat wider - from 70 to 110. With age, a person tends to increase the indicator, from the minimum of the norm to the maximum, which is a physiological norm and does not require medical intervention.
MCV values are independent of gender.
There are several erythrocyte characteristics:
The blood condition will be called normocytosis, microcytosis, macrocytosis or anisocytosis in such conditions.
Macrocytosis, microcytosis and anisocytosis are accompanied by a certain pathology of the circulatory system, or a tendency to it. For example, detection of a large number of microcytes indicates a lack of hemoglobin in the blood. Macrocytosis may indicate liver problems or hormonal imbalances.
| Age | Acceptable values, or norm, fl |
|---|---|
| 1 – 3 days | 75 – 121 |
| 7 days | 86 – 126 |
| 14 – 30 days | 88 – 124 |
| 2 months | 77 – 115 |
| 3 – 6 months | 77 – 108 |
| 16 years | 73 – 85 |
| 7 – 10 years | 75 – 87 |
| 10 – 15 years | 76 – 95 |
| 16 – 20 years | 78 – 98 |
| 21 – 40 years | 80 – 98 |
| 41 – 65 years old | 80 – 100 |
| over 65 years old | 78 – 103 |
When is MCV analysis necessary?
The doctor refers to determining the average volume of red blood cells for the following purposes:
- To give a more in-depth assessment of developing anemia;
- Identify metabolic disorders;
- Determine the degree of water-electrolyte imbalance in the patient;
- To adjust the treatment of severe pathologies.
This analysis is only auxiliary method, shedding light on the nature of disorders in the body.
The reliability of this method in identifying various types anemia or water-electrolyte imbalance is beyond doubt.
Thus, hypertensive hyperhydration in most cases is accompanied by macrocytosis, and in hypotensive patients indicators of microcytosis are recorded.
The MCV indicator, along with other 20 indicators, is included in the general analysis, for which capillary blood is taken from a finger. To prevent measurement errors, it is recommended not to eat before analysis.
For what blood diseases can the analysis be within normal limits?
Often, with severe anemia associated with a deficiency of hemoglobin formation, the volume of erythrocytes may remain within normal limits.
This is observed in the following situations:
When average volume is reduced: what does it mean?
If in the analysis blood MCV below normal, this indicates one of two situations:
- red blood cells, main function which transport hemoglobin through body tissues contain insufficient amounts;
- For some reason, intensive destruction of already mature red blood cells occurs.
These conditions, in which MCV is low, are characteristic of:
If a child's blood test results are lowered to 75 fL, then he is diagnosed with microcytic anemia.
When the mean red blood cell volume is increased
An increase of 115 feet is typical for the following situations:
Red blood cell maturation What does anisocytosis mean?
If found in the blood different sizes erythrocytes - both micro- and macrocytes, then to characterize them, the distribution by volume of red blood cells is determined, which is denoted by the abbreviation RDW.
It is measured using a hemolytic analyzer that differentiates medium cells and determines the heterogeneity of red blood cells, that is, the deviation from the standard volume, and is expressed as a percentage.
The RDW norm is 11.5-14%. To correctly differentiate between anemia and other pathologies, RDW measurement is always carried out in conjunction with MCV measurement.
These measurements revealed the following patterns:
- A reduced MCV with a normal RDW indicates blood transfusion, thalassemia, or a removed spleen.
- With increased MCV and normal RDW, liver pathologies are observed.
- If MCV is decreased and RDW is increased, iron deficiency, beta thalassemia, or erythrocyte sludge syndrome is suspected.
- If both indicators are elevated, then vitamin B12 deficiency, the effects of chemotherapy or cold agglutination are suspected.
It is characteristic that in all the presented disorders of blood structures, one of the most significant reasons is a deficiency of vitamin B12 in the body, and this is not accidental.
This vitamin is the most important factor hematopoiesis, since only in its presence can bone marrow stem cells differentiate towards oxygen carriers, that is, erythrocytes.
And even if all the other necessary elements of red blood cell synthesis are present, if there is a lack of B12, the hematopoietic chain will break.
This essential vitamin for the blood comes to us both from the outside, with food, and is synthesized in large quantities in the large intestine through the activity of beneficial microflora (bifidobacteria and lactobacilli).
Therefore, in order to prevent disorders of hematopoietic function, preventing a reduced amount of this element in food, monitoring intestinal health and a balanced diet is a primary task.
The MCV indicator alone should not be trusted without supporting it with indicators of other erythrocyte indices. For example, the average red blood cell volume will not be accurate if abnormally shaped cells are found in the blood.
Only an integrated approach to assessing blood parameters will allow a doctor to promptly and competently identify an incipient pathology and determine the diagnosis as accurately as possible.
Video: Red blood cells. Volume.
A method for assessing the number, as well as the qualitative aspects of the formed elements, is a detailed blood test. Informative indicators are a specific signal of changes that take place during the period of illness. To carry out analysis, nowadays they use modern laboratory devices - hemolytic analyzers, which is very convenient. But the transcript produced by the device is not always clear to the average person, since the results are written in a foreign language in an abbreviated form.
The analyzer determines from 5 to 20 values in parallel. The article will talk about mean erythrocyte volume (MCV), as one of the primary indicators in clinical analysis. This is the erythrocyte index, a calculated measure that makes it possible to find out the volume occupied by one red blood cell. There are other indices that show the average hemoglobin content in an individual red blood cell (MSN), the average concentration of hemoglobin in the erythrocyte mass (MCHC), width of red blood cell distribution (RDW-CV).
How is MCV determined in a blood test?
The given index can be calculated in femtoliters, as well as in cubic micrometers. It is calculated by dividing the total cell volume by the number of red blood cells. MCV in a blood test is automatically determined by the analyzer. Here's the formula:
MCV = hematocrit (%) x 10 / red blood cell count 10 6 µl
In combination with other erythrocyte indices, such a calculation can identify the processes that cause anemia. If there are many abnormal red blood cells in the blood, as is the case with sickle cell anemia, then the MCV count is unreliable.
Normal mean erythrocyte volume (MCV)
The parameters of the average volume of erythrocytes are unstable; they change with age. In newborns, the volume is maximum and reaches 112 (or even more) fl, and over the course of a year this value drops to 77-79 fl. A gradual decrease in indicators occurs throughout life. More detailed information is shown in the table.
When interpreting the results, the MCV is lower 80 fl is considered as microcytosis, and the value is higher 100 fl interpreted as macrocytosis. The following are reasons why your average red blood cell volume may be high or low.
The average volume of red blood cells is reduced - reasons
Among the factors of reduced MCV is a violation of water-electrolyte balance, or rather hypertonic dehydration, in which all fluid spaces are reduced due to lack of fluid. We are talking about dehydration caused by poor water intake and loss of hypotonic fluid.
The average volume of erythrocytes below normal is recorded in hypochromic and microcytic anemias caused by impaired hemoglobin formation. It is known that hemoglobin tends to influence the type and size of red blood cells. If this protein is in the blood, then the red blood cells will be smaller. Impaired hemoglobin synthesis can also be observed in thalassemia, a genetically determined blood disease.
The average volume of red blood cells is increased - reasons
An increase in MCV can be observed with a lack of cobalt-containing substances (vitamin B 12), when the proportion of red blood cells decreases, but at the same time they become prohibitively large. By the way, on my blog you can read about, as well as the reasons for them.
A slight increase in MCV is associated with smoking, as well as with the use of hormonal contraceptive medications by women of fertile age. In case of alcohol abuse, macrocytosis is always diagnosed, and hemoglobin at the same time remains within the normal range. This detail during laboratory testing makes it possible to suspect alcoholism. The process is reversible and MCV returns to normal approximately one hundred days after stopping drinking alcohol.
The average volume of red blood cells above normal is diagnosed with myxedema (endocrine pathology), liver and bone marrow diseases. Anemia, associated with blood loss and death of red blood cells, plays an important role in increasing the index.
Some sources suggest that prolonged use of antidepressants may give rise to macrocytosis, although the exact connection has not been established.
Now you know why the average volume of red blood cells is increased or decreased, and if you are interested in information about the reasons for the increase in red blood cells themselves, then all the information is in. And in the following articles you will find information about other erythrocyte indices.
A blood test is a study that allows you to find answers to many questions about a person’s health. Each indicator that is part of a qualitative study is important and significant for the diagnosis of any disease, but it is difficult for the average patient to understand some of them.
For example, the mcv number in a blood test can be misleading due to its English abbreviation, but in fact shows the average volume of red blood cells in plasma. Literally this means Mean Cell Volume and is considered a generally accepted calculation value for determining the size of red blood cells.
Red blood cells perform an important function in human blood because they carry oxygen within the body. If their normal quantity or volume is disturbed, functioning problems may arise that need to be sorted out.
Often, a general analysis is done to obtain the volume and number of red blood cells, although in some cases the doctor may order additional tests to obtain this value. In this case, the patient’s blood is taken from a vein on an empty stomach, and the interpretation is carried out by a qualified laboratory specialist or directly by the attending physician.
Average mcv values in blood
mcv is measured using one of two calculation options: often this quantity is determined in femtoliters (fl), but sometimes another value is used - cubic micrometers. The size of red blood cells is maximum in young children, and begins to decrease with age. In newborns, the normal average is 140 fl.
After just a year of a little person’s life, the mcv level in the blood drops almost by half, and its normal level is 70-80 fl. As the child grows older, the indicator may fluctuate within the range of 75-85 fl.
According to world medical standards, the volume of red blood cells in an adult can vary from 80 to 100 fl. And most often, it is slightly higher in women than in men. If the level decreases, the doctor will characterize the red blood cells as microcytic, and if the value is increased, macrocytic.
A peculiarity of the analysis of this indicator is that human plasma may contain red blood cells of different sizes, small and large. This condition is not classified as a pathology; it is important that the average volume of red blood cells remains within normal limits.
Causes of abnormal mcv levels in the blood
There can be a great variety of prerequisites for a decrease or increase in the volume of red blood cells. If deciphering the results showed a violation of the norm in one direction or another, it is necessary to carry out additional diagnostic methods to determine why the analysis showed such a level.
Reduced red blood cell volume
A violation for an adult is a mcv value in a blood test below 80 fl. The prerequisites for such a decrease in this indicator may be:
- dehydration of the body, which leads to disruption of water and electrolyte balance;
- anemia resulting from a lack of hemoglobin in the blood;
- malignant formations in the body.
If the doctor has diagnosed the presence of anemia in the patient, further research will be aimed at clarifying its type and characteristic features.
Anemia is a disease in which the body's normal flow of oxygen is disrupted, which can become a serious problem if left untreated. Oxygen starvation of organs leads to disruption of their functioning, human weakness, sleep disturbance and loss of performance.
The mcv level in the blood is elevated
If the analysis showed an increase in the volume of red blood cells, the value of which exceeded 100 fL, this situation is also a deviation. Doctors call the main reasons for the increase in red blood cell volume:
- alcohol and cigarette abuse;
- women taking oral contraceptives;
- disruption of the endocrine system;
- liver or intestinal diseases;
- drug intoxication.
Deciphering the analysis and further actions
The interpretation of the analysis is carried out only by a doctor. Having noticed an mcv value that is outside the normal range in the results, the specialist must determine the reasons for such a violation. To do this, additional diagnostics are carried out, which includes a survey and study of the patient’s medical history. It is important to find factors in a person’s life that provoke a decrease or increase in the volume of red blood cells.
If diagnostics reveals the presence of a disease, efforts must be directed toward its treatment. Medications, which will be used in this case, affecting a specific problem, will help restore the required volume of red blood cells. There are no medications that can simply affect the mcv value in the blood, and taking them would be inappropriate, since the deviation of this indicator itself is not a disease. It is important to understand what exactly provokes its change.
If the reason for the violation of the norm of red blood cells is an incorrect lifestyle or the consequences of treating a serious disease with antibiotics, the patient’s efforts must be directed to restoring the body. Healthy sleep, moderate exercise, proper nutrition and reception vitamin complexes will help restore the desired shape and normal value of red blood cells.
Thus, mcv in the blood is a reflection of the normal functioning of many organs and systems. Its deviation from the norm can be detected during a general blood test, after which additional studies can be carried out to understand the reasons for changes in the normal volume of red blood cells.
It is important to get advice from a qualified specialist and not to neglect the problem, so as not to treat its complications later.
