Red blood cells in the blood - the norm for age, reasons for increased and decreased levels of red blood cells in a child, women, men

Published: 03/30/2021 17:00:00 Updated: 03/30/2021

Erythrocytes are red blood cells, the most numerous blood cells. Formally, they are not cells, since during the process of maturation they lose many of the structures necessary for cells. For example, they lack nuclei and do not synthesize any protein molecules, unlike other cells in the body. So the name “cell” in this case is used for convenience. Red blood cells are formed in the bone marrow and constantly circulate in the body, performing the most important function of maintaining life - they carry oxygen from the lungs to tissues and organs and remove carbon dioxide.

In addition to red blood cells, blood contains plasma, platelets, and leukocytes. However, the number of red blood cells is so large that just a couple of drops of blood contains about one billion of these cells. They make up about 40% of the total blood volume. Actually, it is red blood cells that give our blood its characteristic red color due to its hemoglobin content.

Red blood cells do not last forever, they wear out over time and eventually die. The average life cycle of a red blood cell is approximately 120 days—a total of four months. However, do not worry, the bone marrow is constantly producing new cells and maintaining the required level of red blood cells. Various unfavorable circumstances can reduce or, conversely, increase their reproduction rate and affect their life expectancy - thus, the balance of blood composition is disrupted. An increase or decrease in red blood cells is associated with various pathological conditions. Let's consider this issue in more detail.

Red blood cells are normal

The normal limits vary depending on gender, age and other characteristics.
So, for an adult man it ranges from 4.0 to 5.1 × 10¹² units per liter of blood, and for women - 3.7 to 4.7 × 10¹² per liter.

In pregnant women, red blood cells may decrease to 3–3.5 x 10¹² per liter.

In children under one year of age, the concentration of red blood cells is constantly changing, so to assess the composition of their blood there is a special table that doctors use when interpreting tests.

In childhood, after one year there are still slight deviations from the “adult” norm, but by adolescence the level of red blood cells levels out.

What does a decrease in platelet levels in the blood indicate?

The lower limit of normal blood platelet content is 150 thousand/μl. The reason for the decrease in PLT (platelet designation in a blood test) may be numerous but rare congenital thrombocytopenias (Fanconi syndrome, Wiskott-Aldrich, etc.), as well as acquired thrombocytopenias. The most common cause of acquired ones is the constant use of antiplatelet drugs, especially with two-component therapy (acetylsalicylic acid + clopidogrel); fortunately, the number of platelets in this case is usually not greatly reduced. Other causes of low blood platelets include bacterial and viral infections, anemia, splenomegaly, congestive heart failure, etc.

Clinical signs of platelet deficiency (bleeding gums, bruising, frequent hemorrhages in the sclera, etc.) appear when the platelet level drops below 50 thousand/µl - this is the indicator when you need to see a hematologist immediately.

Elevated red blood cells

Red blood cells can be elevated due to many reasons, ranging from banal dehydration to erythremia - chronic leukemia.
Therefore, if there are any deviations in test results, you should consult a specialist to determine the cause. An increase in the number of red blood cells is called erythrocytosis, which can be: 1. Primary. A rare hereditary disease characterized by loss of energy, dizziness and darker color of the mucous membranes. 2. Secondary. Caused by other diseases or conditions (for example, smoking or staying in high mountains) and is associated with oxygen starvation of cells.

Thus, the following reasons for the increase in red blood cells can be identified:

Dehydration. When the volume of fluid in the body is reduced, the percentage of red blood cells (and other blood cells) artificially increases.
A lack of oxygen, which the body tries to compensate by producing more red blood cells.
Congenital heart defect. If the heart cannot pump blood effectively, the amount of oxygen reaching the tissues is reduced. The body creates more red blood cells to compensate for oxygen deprivation.
Genetic causes (changes in sensitivity to oxygen, impaired release of oxygen by hemoglobin).
Polycythemia vera is a rare disease in which the body produces too many red blood cells.

Increased production of red blood cells can cause blood to thicken, slow blood flow, and related problems (eg, headaches, dizziness, vision problems, excessive blood clotting).
Often, elevated red blood cell levels are due to dehydration, hot weather, extreme stress, or excessive exercise. A pathological increase in red blood cells is a fairly rare pathology. Much more often, patients encounter reduced levels.

What does an increase in platelet levels in the blood indicate?

The upper limit of normal platelets in a blood test is 400 thousand/µl. Increased platelet levels are much more likely to occur for physiological reasons. These are so-called reactive thrombocytosis. Their cause may be recent physical overexertion, past stress, dehydration, that is, physiological thickening of the blood. Pathological factors most often include those that also thicken the blood - anemia due to chronic blood loss or acute blood loss, dehydration as a result of intoxication. The reasons for an absolute increase in platelet levels include inflammatory diseases, tuberculosis, malignant neoplasms in general and the hematopoietic system in particular.

An increase in platelet levels above 500 thousand/µl significantly increases the risk of thrombosis and requires the selection of antiplatelet therapy - the use of special drugs.

Decreased red blood cells

The main symptoms of low red blood cell count are:

Weakness or fatigue.
Lack of energy.
Paleness of the skin.

Reduced red blood cells are a relatively common pathology.
A low number of red blood cells and/or hemoglobin is called anemia. If there are few red blood cells, there is correspondingly less hemoglobin in the bloodstream, which carries oxygen. Thus, the body experiences oxygen starvation, and we feel weakness, drowsiness, loss of vitality, and dizziness. Due to anemia, hair falls out, the skin becomes pale and dry. There are many forms of anemia, each with its own cause. Anemia can be temporary or acquired; depending on severity - from mild to severe. According to a 2015 publication in The Lancet, about one-third of the world's population is anemic.

The most common causes of low red blood cells are:

Unbalanced diet with deficiency of iron, vitamin B12 or folic acid.
Damage to the bone marrow (toxins, radiation or chemotherapy, infection, certain medications).
Any bone marrow disease.
Chronic inflammatory processes.
Bleeding in the digestive tract (for example, from ulcers, polyps, colon cancer).
Heavy menstrual bleeding.
Trauma with massive blood loss.
Conditions that cause the destruction of red blood cells (for example, hemolytic anemia caused by autoimmune processes or defects in the red blood cells themselves).
Kidney failure – serious kidney pathologies lead to a decrease in erythropoietin (or hematopoietin), a kidney hormone that promotes the production of red blood cells.

The risk of anemia is higher in the following groups:

children aged from 6 months to 2 years;
pregnant or recently given birth women;
following a diet low in vitamins, minerals and iron, red meat;
patients who regularly take medications that cause inflammation of the gastric mucosa (for example, ibuprofen);
having a family history of hereditary anemia such as sickle cell anemia or thalassemia;
patients with an intestinal disorder that affects the absorption of nutrients (eg, Crohn's disease);
have recently experienced major blood loss due to surgery or injury;
people with chronic diseases (HIV, diabetes, kidney disease, cancer, rheumatoid arthritis, heart failure, liver disease).

General (clinical) blood test: interpretation and norm

A complete blood count provides essential information about the types and numbers of blood cells, especially red blood cells, white blood cells and platelets. Using a general blood test, the treating doctor can detect the nature of symptoms such as weakness, fatigue, and bruising. A complete blood count is used to diagnose anemia, infection and many other disorders.

A general (clinical) blood test includes the following indicators:

Absolute white blood cell count ( WBC ). White blood cells protect the body from infection. If an infection develops, these cells attack and destroy bacteria, viruses, or other pathogenic organisms. White blood cells are larger in size than red blood cells, but their number is less. When a person gets sick, the number of white blood cells increases very quickly. Sometimes white blood cell counts are used to detect infection or to evaluate the effectiveness of cancer treatment.
Determination of the ratio of different types of white blood cells (leukogram). The main types of leukocytes are neutrophils, lymphocytes, monocytes, eosinophils and basophils. Counting immature neutrophils, also called band neutrophils, is part of this test. The number of each cell type can provide important information about the health of the immune system. Too high or too low the number of one type of cell may indicate an infection, an allergy or toxic reaction to a drug or chemical, or various diseases such as leukemia.
Absolute red blood cell count ( RBC ). Red blood cells carry oxygen from the lungs to the rest of the body. They also carry carbon dioxide back to the lungs for exhalation. When the level of red blood cells is low (anemia), the body does not receive enough oxygen. When levels are high (polycythemia), there is a risk of red blood cell clots that can block tiny blood vessels (capillaries), also making it difficult to carry oxygen.
Hematocrit ( HCT , precipitated red blood cell volume, PCV ). This test measures the volume of blood per red blood cells. For example, a hematocrit value of 38 means that 38% of the blood is red blood cells. Hematocrit and hemoglobin are the two main tests for detecting anemia or polycythemia.
Hemoglobin ( Hgb ). Hemoglobin molecules are found in red blood cells; they carry oxygen and give the blood its red color. A hemoglobin test measures the level of hemoglobin in the blood and shows how the body copes with transporting oxygen.
Erythrocyte index. There are three red blood cell indices: mean erythrocyte volume (MCV), mean erythrocyte hemoglobin content (MCH) and mean erythrocyte hemoglobin concentration (MCHC). All of them are calculated using special equipment, and the numbers are derived from other indicators of a general blood test. MCV reflects the size of red blood cells, MCH is the average hemoglobin content in an individual red blood cell, MCHC is the hemoglobin concentration in an individual red blood cell. These indices are used in diagnosing various types of anemia. The red blood cell distribution width (RDW) index is also calculated, which reflects the difference in size and shape between cells.
Absolute platelet count. Platelets are the smallest type of blood cell. They play an important role in the blood clotting process. If bleeding occurs, the platelets are activated and bind together, forming a plug that prevents bleeding. If the number of red blood cells is insufficient, there is a risk of uncontrolled bleeding. If there is an excess amount, there is a risk of thrombus formation in a blood vessel. In addition, platelets can be involved in the formation of sclerotic plaques on artery walls (atherosclerosis).
Mean platelet volume ( MPV ). This indicator reflects the average value of the measured platelet volume. MPV is used in conjunction with platelet count to diagnose certain diseases. If the platelet count is normal, the MPV may be low or high.

Your doctor may also order a blood smear microscopy at the same time as your complete blood count, but this is not part of your routine blood test. For this test, a drop of blood is placed on a plate and diluted with dye. The plate is examined under a microscope, noting the number, size and shape of red blood cells, white blood cells and platelets. Differences in the shape or size of blood cells can indicate various diseases, such as leukemia, malaria or sickle cell disease.

A clinical blood test is carried out for the following purposes:

Finding the cause of symptoms such as fatigue, weakness, fever, bruising, or weight loss
Diagnosis of anemia
Establishing the amount of blood lost during bleeding
Diagnosis of polycythemia
Diagnosis of infections
Diagnosis of blood diseases, such as leukemia
Monitoring the body's response to drug treatment and radiation therapy.
Monitoring the blood cell response to abnormal bleeding.
Screening of indicators before surgery.
Tracking high or low levels is used to detect various diseases, such as high eosinophil levels that may indicate allergies or asthma.

A complete blood count is performed as part of a routine medical examination. A complete blood count provides valuable information about the overall condition of the body and health.

Preparing for the examination

No special preparation required.

How is the examination carried out?

The shoulder is tightened with an elastic tourniquet to stop the blood flow. The veins under the tourniquet become larger, making it easier to insert the needle.
The puncture site is cleaned with alcohol.
The needle is inserted into the vein. Sometimes more than one injection is required.
A blood collection tube is attached to the needle.
When enough blood has been collected, the tourniquet is removed.
After the needle is removed, a cotton swab is applied to the injection site.
The area should be pressed and a bandage applied.

If a baby's blood is being tested, a heel prick is done instead of drawing blood from a vein.

Feelings during the procedure

A blood sample is taken from a vein in the arm. The forearm is wrapped with an elastic band, so there may be a feeling of tightness. You may not feel any pain from the needle, but sometimes there will be a slight burning sensation or pain.

Complications

When taking blood from a vein, the chance of complications occurring is very small.

There may be a slight bruise. By pressing the tampon to the puncture site for a few minutes, you can reduce the chance of its occurrence.
In rare cases, the vein may become swollen, this is called phlebitis. The problem can be treated with several warm compresses.
Continuous bleeding may occur in patients with blood disorders. Taking medications such as aspirin, warfarin (such as Coumadin), and other blood thinners increases the chance of bleeding. Tell your doctor before taking a sample if you have problems with blood clotting or are taking blood-thinning medications.

results

A complete blood count provides important information about the types of blood cells - red blood cells, white blood cells, platelets - and their numbers. A complete blood count helps determine the cause of various symptoms such as weakness, nausea, bruising and is used in the diagnosis of various diseases - anemia, infections and many others.

Normal results

IMPORTANT! The normal values, or range of normal values, given here are average values. These vary depending on the laboratory, so where you are being tested will have different readings. The laboratory report should contain information about the reference range used. In addition, overall health and other factors are taken into account when analyzing the results. Therefore, a value that does not fit into the range presented here may be normal for you personally.

The normal range depends on your age, gender, type of blood sample, and how high above sea level the area where you live is. The doctor can use all the indicators of the general blood test when checking the condition of the body. For example, the number of red blood cells, hemoglobin, hematocrit are the main indicators in diagnosing anemia, but erythrocyte indices and smear microscopy also help detect this disease and can show the possibility of its occurrence.

To assess the number and size of leukocytes, the doctor takes into account the results of counting the number of cells and the ratio of their types. To see if there are too many or few cells of a certain type, the doctor compares their number and percentage. There is a norm for each type of leukocyte.

Indicators may change during pregnancy. During each trimester, your doctor should report changes in your normal range.

Absolute white blood cell count ( WBC )
Men and non-pregnant women:	5,000–10,000 WBC per cubic mm (mm3) or 5.0–10.0 x 109 WBC per 1 liter (L)

The ratio of different types of leukocytes
Neutrophils:	50%–62%
Band neutrophils:	3%–6%
Lymphocytes:	25%–40%
Monocytes:	3%–7%
Eosinophils:	0%–3%
Basophils:	0%–1%

Absolute red blood cell count ( RBC )
Men:	4.5–5.5 million RBC per µl or 4.5–5.5 x 1012/l
Women:	4.0–5.0 million RBC per µL or 4.0–5.0 x 1012/L
Children:	3.8–6.0 million RBC per µL or 3.8–6.0 x 1012/L
Newborns:	4.1–6.1 million RBC per µL or 4.1–6.1 x 1012/L

Hematocrit (HCT)
Men:	42%–52% or 0.42–0.52 of the total volume
Women:	36%–48% or 0.36–0.48 of total volume
Children:	29%–59% or 0.29–0.59 of the total volume
Newborns:	44%–64% or 0.44–0.64 of total volume

Hemoglobin (Hgb)
Men:	14–17.4 grams per deciliter (g/dL) or 140–174 grams per liter (g/L)
Women:	12–16 g/dl or 120–160 g/l
Children:	9.5–20.5 g/dl or 95–205 g/l
Newborns:	14.5–24.5 g/dl or 145–245 g/l

Typically, a normal hemoglobin level is one third of the hematocrit level.

Red blood cell indices
Mean erythrocyte volume ( MCV ) - Adults:	84–96 femtoliters (fl)
Mean erythrocyte hemoglobin content ( MCH ) - Adults:	28–34 picograms (pg) per cell
Mean erythrocyte hemoglobin concentration ( MCHC ) - Adults:	32–36 grams per deciliter (g/dL)

Red blood cell distribution width by volume ( RDW )
Norm:	11.5%–14.5%

Absolute platelet count
Adults:	140,000–400,000 platelets per mm3 or 140–400 x 109/L
Children:	150,000–450,000 platelets per mm3 or 150–450 x 109/L

Mean platelet volume (MPV)
Adults:	7.4–10.4 µm3 or 7.4–10.4 fl
Children:	7.4–10.4 µm3 or 7.4–10.4 fl

Blood smear microscopy
Norm:	Normal indicators of the number, shape, color and size of blood cells.

High performance

Absolute red blood cell count (RBC)

Conditions and habits that cause high red blood cell counts include smoking, exposure to carbon monoxide, long-term lung disease, kidney disease, some cancers and heart disease, alcoholism, liver disease, a rare bone marrow disease (polycythemia vera), or rare problems related to with hemoglobin, which are associated with the transfer of oxygen.
Diseases related to the water component of the body can also cause high red blood cell counts. These include dehydration, diarrhea, vomiting, increased sweating, and taking diuretics. Lack of fluid in the body causes red blood cell counts to appear high. This is sometimes called pseudopolycythemia.

Absolute white blood cell count (WBC)

Causes of high white blood cell counts include infection, inflammation, tissue damage (for example, due to a heart attack), kidney failure, lupus, tuberculosis, rheumatoid arthritis, malnutrition, leukemia, and cancer.
Taking costosteroids and certain medications, underactive adrenal glands, problems with the thyroid gland, and removal of the spleen can also cause an increase in white blood cell levels.

Absolute platelet count

High platelet levels can occur due to bleeding, iron deficiency, cancer and bone marrow problems.

Low performance

Absolute red blood cell count (RBC)

With anemia, the level of red blood cells decreases. Anemia can be caused by heavy menstrual bleeding, stomach ulcers, colorectal cancer, inflammatory bowel disease, tumors, Addison's disease, thalassemia, lead poisoning, sickle cell disease, or a reaction to certain chemicals and medications. One reason for low red blood cell counts may be removal of the spleen.
Not getting enough folic acid or vitamin B12 can also cause anemia, such as pernicious anemia, which causes problems absorbing vitamin B12.
Red blood cell indices and smear microscopy can help find the cause of anemia.

Absolute white blood cell count (WBC)

Low white blood cell counts may be caused by chemotherapy and reaction to drug treatment, aplastic anemia, viral infections, malaria, alcoholism, AIDS, lupus, Cushing's syndrome.
An enlarged spleen can reduce white blood cell counts.

Absolute platelet count

Low platelet levels can be caused by pregnancy, immunopathological thrombocytopenic purpura and other diseases that affect the process of generating platelets or destroy them.
An enlarged spleen can reduce platelet counts.

What can affect the results of the examination?

Reasons why the analysis is not possible or the results will be incorrect:

When drawing blood, your arm was tied with an elastic tourniquet for a long time.
Taking drugs that cause low platelet counts, such as certain antibiotics, steroids, thiazide diuretics, chemotherapy drugs, quinidine, meprobamate.
Very high levels of white blood cells or fats (triglycerides) can cause falsely high hemoglobin levels.
With an enlarged spleen, the level of platelets (thrombopenia) or white blood cells may be reduced; this condition can also cause some types of cancer.
During pregnancy, the level of red blood cells is often reduced, and less often, the level of white blood cells is increased.

On a note:

The absolute white blood cell count can reach up to 2000 WBC per microliter due to exercise, stress or smoking.
Children tend to have higher levels of white blood cells than adults.
Often, a red blood cell count test includes:
Erythrocyte sedimentation rate (ESR). The ESR test measures how quickly red blood cells settle to the bottom of a tube. During inflammatory processes occurring in the body (for example, in the presence of infection or cancer), red blood cells settle more slowly than under normal conditions. Using ESR analysis, inflammatory diseases can be diagnosed if the blood test results are normal.
Analysis of reticulocyte content. This is an analysis of the number of young red blood cells in a blood sample. As a rule, the content of reticulocytes is lower compared to the content of mature red blood cells. However, recent bleeding or destruction of mature red blood cells may cause increased reticulocyte production. This test is done to detect certain types of anemia and screen for the body's response to treatment.
Hematocrit measurements may vary depending on the assay method and equipment used.

Deviation from the norm is not always a disease

If the level of red blood cells during the first analysis is slightly outside the normal range, do not panic.
Your doctor will help you interpret the results correctly, taking into account your individual characteristics and medical history. A single slightly elevated or slightly decreased result may have no medical significance. There are several factors that can cause a test result to fall outside the established reference range without pathological reasons:

Under the influence of external factors (stress, previous infections, physical activity), the results of the analysis of the same person may differ slightly. In this case, a person can be healthy. If the analysis shows a slight deviation, retake the test on another day.
Individual characteristics. For some people, the boundaries of the norm may differ slightly from generally accepted ones. Reference values are valid for the vast majority of people, but we are all different, and in some rare cases, a healthy person may have their own norms, slightly different from the usual values.

Only a doctor can accurately determine this after conducting additional research.

Description of the causes of erythrocytosis

An excess of red blood cells in the blood plasma is called erythrocytosis. As a result, the blood begins to thicken and moves through the capillaries with difficulty. Red blood cell production spontaneously increases in the body when oxygen levels in cells decrease. Lack of oxygen can be caused by congenital pathology of the heart muscle, heart failure, hemoglobinopathy, chronic obstructive pulmonary disease, and excessive smoking.

It is possible to regulate the formation of red blood cells with the help of certain drugs. These include anabolic steroids, erythropoietin protein and some groups of antibiotics intended for the treatment of infectious and inflammatory processes in hematopoiesis.

The consequence of an increase in red blood cells in blood cells can be dehydration, which occurs as a result of an increase in temperature in the body, the occurrence of gag reflexes and loose stools. During such deviations, the concentration of red blood cells increases, but their number does not change.

Tests for red blood cells

A red blood cell count and cell count is usually done as part of a complete blood count (CBC).
A general blood test is the most common analysis, informative for almost any pathological process. This test can also be used to diagnose and/or monitor a number of diseases that affect the production or lifespan of red blood cells. You can take a general blood test with determination of 5 fractions of leukocytes at any CityLab medical center.

For an accurate diagnosis, the doctor may prescribe additional tests:

Reticulocyte count - determines the number of immature red blood cells.
Iron test - this trace element plays an important role in the production of red blood cells.
Vitamin B12 and folic acid levels – these vitamins are also important for red blood cell production.
A blood test for ferritin reflects iron reserves in the body.
Serum iron, total iron-binding capacity of blood serum are additional parameters reflecting the process of iron metabolism in the body.

What indicators does the blood test contain?

Donating blood for testing is necessary during planned hospitalization, to assess the effectiveness of the therapy, and during pregnancy. To make an accurate diagnosis and prescribe treatment, the doctor always prescribes a general blood test. Material for research is taken from a finger or from a vein. The second option is preferable, since venous blood more accurately shows the level of hemoglobin and red blood cells.

First of all, red blood cells, white blood cells and platelets are analyzed, as well as:

Hemoglobin level.
Erythrocyte indices.
Hematocrit level.
Reticulocyte count.

Additionally, the erythrocyte sedimentation rate (ESR), color and blood clotting period are determined.

An extended study involves indicating the leukocyte formula, including the count of eosinophils, lymphocytes, monocytes, band and segmented neutrophils.

Prevention of increased red blood cells

The cause of the increased production of red blood cells is determined by the doctor. To maintain normal red blood cell levels, it is enough to adhere to preventive measures.

To avoid increased blood concentrations, it is recommended to drink more fluid. The water must be purified, so it is better to buy it in bottles or collect it from wells.

Eating fresh vegetables and fruits has a good effect on blood composition. They contain many vitamins and microelements that regulate the content of red blood cells.

You can reduce the concentration of red cells in the blood by eliminating foods containing iron from your diet. You will have to give up red meat, liver, beans, lentils, spinach, cabbage, prunes and raisins. Avoid drinking caffeinated drinks, smoking or taking aspirin. Regular physical activity will help regulate red blood cell levels.