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Red blood cell anisocytosis.
Last reviewed: 07.06.2024
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Red blood cell anisocytosis (RDW) is an index that measures variability in the size of red blood cells in the blood. Normally, red blood cells should be the same size and shape, but anisocytosis can result in the presence of both large and small red blood cells in the blood. RDW is usually expressed as a percentage and can be used to assess the homogeneity or heterogeneity of red blood cell size. This indicator can be useful in the diagnosis of various conditions, including anemia and other blood diseases.
Anisocytosis can be detected in blood tests using medical laboratory techniques. It can indicate a variety of conditions and diseases, including:
- Iron deficiency anemia: One of the most common causes of anisocytosis is iron deficiency, which can lead to anemia. In this case, small microcytes and large macrocytes may coexist in the blood.
- Vitamin deficiencies: Deficiencies of vitamins such as folic acid or vitamin B12 can also cause anisocytosis.
- Hemolytic anemias: In some types of anemia, in which red blood cells are destroyed faster than normal, abnormal red blood cell shapes may appear.
- Thalassemia: This is a group of genetic disorders that affect the structure of hemoglobin and can cause anisocytosis.
- Other blood disorders and conditions: Anisocytosis may also be associated with other conditions such as sideroblastic anemia, alcohol abususus, chronic liver disease, and others.
For an accurate diagnosis and treatment if anisocytosis is found, it is important to perform additional medical tests and consult with a doctor. Only a specialist will be able to determine the specific causes of anisocytosis and recommend the necessary treatment.
The red blood cell anisocytosis score is measured using special laboratory techniques such as blood tests or hematologic analysis. It is usually expressed as a percentage and reflects the percentage of abnormally small (microcytes) or abnormally large (macrocytes) red blood cells in the total number of red blood cells in the blood.
In order to interpret the anisocytosis score, it is important to know the normal ranges of the anisocytosis score, which can vary depending on the laboratory and method of analysis. Typically, normal anisocytosis values are in the range of 11-15%.
If anisocytosis is outside the normal range, it may indicate various conditions and diseases such as iron deficiency anemia, vitamin deficiencies, hemolytic anemia, thalassemia, and others. However, anisocytosis itself is only an indicator, and additional testing and consultation with a physician is required to make an accurate diagnosis and determine the cause of anisocytosis.
Erythrocyte anisocytosis index RDW and mean erythrocyte volume MCV
MCV is one of the parameters used in hematologic blood tests to estimate the size and volume of red blood cells, that is, red blood cells. MCV is measured in cubic micrometers (fl) or femtoliters (fl) and represents the average volume of a single red blood cell.
The anisocytosis index (MCV) is an important component of a general blood test and can be useful in diagnosing various conditions such as anemia. Normal MCV values are usually in the range of 80-100 fl. However, specific normal ranges may vary from laboratory to laboratory.
The interpretation of MCV can be as follows:
- Normocytosis: MCV within normal limits (80-100 fl).
- Microcytosis: MCV is lower than normal, indicating small red blood cells. This may be due to iron deficiency anemia or other conditions.
- Macrocytosis: MCV is higher than normal, which means that large red blood cells are present. This may be due, for example, to megaloblastic anemia caused by a deficiency of vitamin B12 or folic acid.
Interpretation of MCV requires additional analysis and evaluation of other blood parameters for a more accurate diagnosis and to identify the causes of anisocytosis. Determination of MCV is an important step in the diagnosis of anemia and other hematologic conditions, and its interpretation should be entrusted to a physician.
Anisocytosis and poikilocytosis
These are two terms used to describe changes in red blood cells (red blood cells) in a blood test. They can accompany a variety of medical conditions and are important indicators when evaluating blood conditions. Here are their definitions:
- Anisocytosis: This term refers to the presence of red blood cells of different sizes in a blood sample. Normally, red blood cells are all the same size, but anisocytosis can indicate the presence of various medical conditions, including different types of anemia.
- Poikilocytosis: Poikilocytosis indicates the presence of informal or altered forms of red blood cells in the blood. This may include cells with different shapes such as curved, concave, or altered. Poikilocytosis can also be associated with various types of anemia and other conditions.
Examination of anisocytosis and poikilocytosis on blood tests helps physicians determine the presence and nature of anemia and can be helpful in establishing a diagnosis and selecting appropriate treatment. It is important that the interpretation of the test results be performed by a physician to determine the patient's specific medical condition and develop an appropriate treatment plan.
Raising and lowering of values
Increased anisocytosis of red blood cells (changes in their size and shape) can be a sign of various conditions and diseases. Causes of increased RDW and MCV:
RDW (red blood cell angular deviation) and MCV (mean corpuscular volume) are two important parameters that reflect the characteristics of red blood cells in the blood. Elevated levels of these can be associated with various conditions and diseases. Here are some of the possible causes that can lead to elevated RDW and MCV:
- Iron deficiency anemia: One of the most common cases of elevated RDW and MCV is associated with iron deficiency anemia. In this case, red blood cells may become smaller or larger than normal due to a lack of iron for normal hemoglobin formation.
- Vitamin B12 and folic acid: Vitamin B12 or folic acid deficiency can cause megaloblastic anemia, in which red blood cells increase in size (increased MCV) and have different sizes (increased RDW).
- Alcohol: Excessive alcohol consumption can lead to alcoholic macrocytosis, in which red blood cells increase in size and MCV increases.
- Myelodysplastic syndrome (MDS): MDS is a group of hematopoietic disorders that can cause anisocytosis (increased RDW) and increased red blood cell size (increased MCV).
- Other anemias: Some other anemias, including aplastic anemia and hemolytic anemia, may also result in changes in RDW and MCV.
- Other conditions: Some diseases and conditions such as myelofibrosis, chronic hepatitis, and Crohn's disease may also affect blood parameters including RDW and MCV.
Elevated anisocytosis requires additional medical evaluation and diagnosis to determine the specific cause. The doctor may prescribe additional blood tests and examinations to identify the underlying disease and develop appropriate treatment.
An isolated increase in RDW (red blood cell angular deviation) in a blood test can also be caused by a variety of reasons. RDW measures the variability in the size of red blood cells in the blood, and its level can change in response to various factors. Here are some possible causes of an isolated increase in RDW:
- Iron deficiency: One of the most common and frequent factors leading to increased RDW is iron deficiency. Iron deficiency can cause changes in the shape and size of red blood cells, which is reflected in an increase in RDW.
- Vitamin B12 and folic acid deficiency: Deficiency of these vitamins can also affect the shape and size of red blood cells, resulting in increased RDW.
- Hemolytic anemia: Hemolytic anemia, in which red blood cells break down faster than normal, can cause an increase in RDW because of the diversity of red blood cell sizes in the blood.
- Other blood disorders: Some other blood disorders, such as thalassemia and anemia with small thrombocytopenia, may also result in elevated RDW.
- Taking certain medications: Some medications, such as cytotoxic drugs and anti-inflammatory drugs, can cause changes in blood counts and increase RDW.
- Chronic diseases: Some chronic diseases, such as chronic inflammatory processes, can also affect blood composition and lead to changes in RDW.
- Test Errors: Sometimes elevated RDW values can be due to errors in performing blood tests.
If you have an isolated elevation of RDW in a blood test, it is important to contact your physician for further evaluation and identification of the cause. Elevated RDW may be a clinical sign of a medical condition and its interpretation requires a comprehensive analysis of other blood parameters and clinical data.
An elevated RDW (red blood cell angular deviation) with a simultaneously low MCV (mean red blood cell volume) may indicate the presence of certain blood count changes and diseases. In this context, high RDW and low MCV may be associated with the following causes:
- Iron deficiency anemia: This is the most common cause in which RDW increases and MCV decreases. Iron deficiency anemia occurs due to iron deficiency, which leads to changes in the size and shape of red blood cells, making them smaller and more diverse, which is reflected in RDW values.
- Thalassemia: Some forms of thalassemia, a genetic disorder, affect the size and shape of red blood cells, which can result in a simultaneous increase in RDW and decrease in MCV.
- Hemolytic anemia: Hemolytic anemia, in which red blood cells break down faster than normal, can also cause an elevated RDW and decreased MCV due to changes in red blood cell size.
- Anemias of chronic diseases: Some chronic diseases, such as chronic inflammatory conditions or cancer, can affect blood composition and cause changes in parameters including RDW and MCV.
- Sideroachrestic anemia: This is a rare disorder that can also cause high RDW and low MCV.
- Severe blood loss: Acute or chronic blood loss, such as from the gastrointestinal tract, can cause anemia with high RDW and low MCV.
If you have blood test abnormalities such as elevated RDW and low MCV, it is important to see your doctor for further diagnosis and to determine the cause. These values may signal the presence of a medical condition, and the exact cause requires further testing and consultation with a specialist.
An isolated decrease in RDW (red blood cell angular deviation, when most red blood cells are similar in size and shape) in a blood test can be normal and does not always indicate a medical condition. RDW measures variability in the size of red blood cells in the blood and can be altered in response to various factors. Here are some possible causes of an isolated decrease in RDW:
- Reduced anisocytosis may be associated with some hereditary forms of anemia, such as microspherocytosis, in which red blood cells have an increased spherical shape and a more monotonous size. However, these conditions are rare and usually require specialized medical evaluation and diagnosis.
- Vitamin B6 deficiency: Vitamin B6 (pyridoxine) deficiency can affect red blood cell size and lead to decreased RDW.
- Iron deficiency state: In rare cases, RDW may be low in the presence of iron deficiency. However, in most cases of iron deficiency, RDW is elevated.
- Thalassemia: In some forms of thalassemia (a genetic disorder affecting hemoglobin), RDW may be decreased.
- Test errors: Sometimes low RDW values can be due to errors in the blood test.
If you have questions or concerns about the result of anisocytosis in your blood tests, it is recommended that you consult with a physician who can review your results, perform additional tests, and make recommendations for further testing and treatment if necessary.
Red blood cell anisocytosis in pregnancy
May be related to various physiologic changes that occur in a woman's body during pregnancy. These changes can affect the size and shape of red blood cells (red blood cells). Here are a few factors that may contribute to anisocytosis in pregnant women:
- Iron deficiencyanemia: One of the most common causes of anisocytosis in pregnant women is iron deficiency anemia. During pregnancy, a woman needs more iron to maintain normal hemoglobinization and red blood cell formation. If she does not get enough iron from food or due to other factors, iron deficiency anemia and anisocytosis can result.
- Physiologic changes in pregnancy: During pregnancy, blood volume increases and the shape and size of red blood cells may be affected. Some women may have a slight anisocytosis without obvious signs of anemia.
- Other medical conditions: In rare cases, anisocytosis in pregnant women may be caused by other medical conditions such as blood diseases or metabolic disorders.
Anisocytosis of red blood cells in a child
Means that his blood test shows a change in the size of red blood cells, that is, the red blood cells are of different sizes. This can be a normal physiologic phenomenon in children, especially infants, as their blood may not yet be fully mature.
However, anisocytosis can also be associated with various medical conditions and abnormalities such as anemia, disorders of red blood cell formation, and other blood disorders. It is important to consult a pediatrician or pediatric hematologist for a more detailed analysis and to determine the cause of anisocytosis in your child.
Treatment of red blood cell anisocytosis
Treatment of anisocytosis depends directly on its cause. Anisocytosis can result from a variety of diseases and conditions, so it is important to identify the underlying disease and focus on treating it. Here are some examples of possible treatment approaches:
- Iron deficiency anemia: If anisocytosis is associated with iron deficiency anemia, treatment will focus on correcting the iron deficiency. The doctor may prescribe iron-containing medications and recommendations for dietary changes.
- Thalassemia: Treatment of thalassemia depends on its type and severity. Some forms may require blood transfusions or specific drug therapy.
- Hemolytic anemia: In the case of hemolytic anemia, treatment is aimed at controlling the factors that cause the destruction of red blood cells. The doctor may prescribe anti-inflammatory drugs or other medications depending on the cause of the anemia.
- Treatment of the underlying disease: It is important to treat the underlying disease or condition that is causing the anisocytosis. For example, if it is associated with a chronic disease, managing the disease may improve the blood condition.
Treatment requires an individualized approach and determination of its cause. This should be done under the supervision of a doctor, who will perform the necessary tests and develop a treatment plan appropriate to the specific case. Do not try to treat anisocytosis yourself without consulting a medical specialist, as improper treatment may worsen the situation.