The RDW blood test is a component of the entire blood count. It’s used for the diagnosis of anemia and conditions corresponding to thalassemia.
Certainly one of the parameters that usually cause concern after receiving the outcomes of a blood count is the RDW (red cell blood distribution width) or ‘red cell distribution width test’. It indicates the variability in the dimensions of red blood cells, that are answerable for transporting oxygen from the lungs to the remainder of the body’s cells. What do high or low values indicate?
A high RDW indicates that there’s a major difference between the dimensions of the smallest and largest red blood cells. It normally applies to those situations where many red blood cells are larger than normal, although the other may also be true. This criterion is commonly utilized in the diagnosis of anemia.
If the values are below what is taken into account normal, it doesn’t normally indicate a disease, unless it’s observed that other variables – corresponding to mean corpuscular volume (MCV)- are also low. In the next article, we’re going to let you know more in regards to the significance of this indicator within the CBC.
What’s RDW?
The RDW (red blood cell distribution width) is a parameter that is a component of the entire blood count or CBC test. It reflects the dimensions distribution of red blood cells (erythrocytes) and is expressed in percentages, with normal values being 12 to fifteen%.
A term that typically refers to something similar is anisocytosis, although the latter is a consequence of direct commentary of red blood cells in a peripheral blood smear (under the microscope).
On this peripheral blood smear, the phenomenon of anisocytosis may be observed, during which there’s variation in the dimensions of red blood cells. It’s a definite alteration but related to RDW.
Returning to RDW, if the share is higher than 15%, it’s indicative of alterations within the blood. It’s not a really specific parameter, because the causes of those volume variations may be very diverse, corresponding to vitamin B12 deficiency and alcoholism.
Subsequently, it’s a test that’s traditionally used to diagnose the differing types of anemia. Sometimes it’s also used concurrently with other tests to confirm conditions corresponding to thalassemia, liver and kidney disease, diabetes, and even some sorts of hematological tumors.
What does a high RDW value on a CBC mean?
When the RDW is high on the CBC it implies that there’s a greater variation in the dimensions of the red blood cells. When RDW values are observed to be high, an interpretation is made together with hemoglobin and mean corpuscular volume (MCV) levels to differentiate between various kinds of anemia or other diseases.
Its most typical causes include the next conditions:
- Iron deficiency anemia: This happens due to iron deficiency, so hemoglobin can’t be synthesized properly. Subsequently, hemoglobin could be low and MCV decreased.
- Megaloblastic anemia: That is attributable to a deficiency of folic acid or vitamin B12, mandatory for DNA synthesis within the precursors of those cells. Hemoglobin could be low and MCV high, typical of this disease.
- Thalassemias: These are a bunch of genetic disorders during which abnormal types of hemoglobin are synthesized. Each hemoglobin and MCV could be low.
- Liver disease: For the reason that liver
- s functions of metabolism and elimination of waste substances are impaired when there’s a disease present, the size of red blood cells is commonly altered.
The outcomes of research published within the journal Plos One suggest that prime RDW within the blood count has a predictive value for other chronic diseases, corresponding to type 2 diabetes, cardiovascular pathologies (especially heart failure), and cancer.
At present, there’s no specific treatment to revive RDW values to normal levels. That’s why it’s mandatory to acquire a diagnosis of the disease that’s causing the alteration with a view to follow an adequate and effective protocol.
Recommendations for lowering a high RDW
To lower a high RDW, it’s mandatory to intervene on the underlying cause. Treatment options vary depending on the related disease. Nonetheless, some general advice to assist restore these parameters to normal values is as follows:
- Get regular physical exertion.
- Sleep between 7 and 9 hours a day.
- Avoid alcohol and tobacco consumption.
- Increase your consumption of foods wealthy in iron, vitamin B9, or vitamin B12 (depending on the variety of anemia).
What does a low RDW value mean?
A low RDW count within the CBC is generally of no clinical significance, because it isn’t indicative of a disease. Especially when the opposite parameters (hemoglobin and MCV) will not be altered.
Nonetheless, if the mean corpuscular volume (MCV) is altered and the RDW is low, it’s mandatory to analyze whether that is because of diseases corresponding to kidney problems, HIV, cancer, diabetes, or liver disease. Your doctor may suggest additional tests.
High RDW often indicates anemia
Several disorders that affect red cell volume can result in an elevated RDW. Typically, it’s related to deficiency anemias (corresponding to iron deficiency anemia and megaloblastic anemia). It may also indicate thalassemia, liver disease, and other chronic conditions.
Regardless of the case, it’s essential to seek medical attention to seek out out which disease is behind this alteration within the hemogram. Once established, the physician can provide guidance on the suitable treatment for the situation.
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