If you need to know which are the RDW reference ranges or you require more information about the role of RDW in the blood, you can visit normal RDW level in the blood
A high RDW is called anisocytosis, a condition where the red blood cells are unequal in size. The RDW is essentially an indication of the degree of anisocytosis (abnormal variation in size of RBCs).
A high RDW percentage is useful in the existence of anemia (hemoglobin low) and it should be studied within the MCV (Mean Corpuscular Volume) to discern the different types of anemia:
The main utility of RDW test is:
A very high level of RDW may be a sign of sideroblastic anemia.
Anisocytosis or a high RDW level in the blood means:
RDW levels are slightly high. If only this parameter is over the limit is not a matter for concern. It may be due to infection, vigorous exercise or to certain drugs.
If there is microcytic anemia (low hemoglobin and low MCV), it may be a first sign of iron deficiencyanemia.
A moderate anisocytosis may be a sign of severe iron deficiency anemias (very low hemoglobin and low MCV) but is more characteristic of a megaloblastic anemia (due to vitamin B12 or folic acid deficiency) with a high MCV.
A severe anisocytosis may be a sign of sideroblastic anemia.
It can also be seen when hemoglobin is very low (below 6 mg/dl) in iron deficiencyanemia (low MCV) and in megaloblastic anemia (high MCV).
Another possibility is the existence of two different red cell populations, such as in a person that just received a transfusion. This can also happen when the person is under treatment for iron deficiencyanemia or megaloblastic anemias. In this situation, RDW values can exceed 30% and it usually means a positive response to treatment.
There are some health circumstances than can raise your RDW level in the blood:
The most common diseases why the RDW can be higher than normal are:
The RDW depends on numerous factors. For that reason, the best solution to improve in the long term the RDW level is to treat the underlying disease.
In fact, when a treatment for anemia is prescribed, at the beginning, it usually shows an increase in the short term that is usually a positive sign.
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The following values are considered to be above the normal range:
IMPORTANT: These levels are expressed in %. They are an example of a healthy woman of about 45 years old with no known disease and not taking any medication. The ranges can be different depending on the laboratory or on your personal circumstances.
RDW | |||||||
|---|---|---|---|---|---|---|---|
| Mild anisicytosis | |||||||
| 14.6 % | 14.7 % | 14.8 % | 14.9 % | 15 % | 15.1 % | 15.2 % | 15.3 % |
| 15.4 % | 15.5 % | 15.6 % | 15.7 % | 15.8 % | 15.9 % | 16 % | 16.1 % |
| 16.2 % | 16.3 % | 16.4 % | 16.5 % | 16.6 % | 16.7 % | 16.8 % | 16.9 % |
| 17 % | 17.1 % | 17.2 % | 17.3 % | 17.4 % | 17.5 % | 17.6 % | 17.7 % |
| 17.8 % | 17.9 % | 18 % | |||||
| Moderate anisicytosis | |||||||
| 18.1 % | 18.2 % | 18.3 % | 18.4 % | 18.5 % | 18.6 % | 18.7 % | 18.8 % |
| 18.9 % | 19 % | 19.1 % | 19.2 % | 19.3 % | 19.4 % | 19.5 % | 19.6 % |
| 19.7 % | 19.8 % | 19.9 % | 20 % | 20.1 % | 20.2 % | 20.3 % | 20.4 % |
| 20.5 % | 20.6 % | 20.7 % | 20.8 % | 20.9 % | 21 % | 21.1 % | 21.2 % |
| 21.3 % | 21.4 % | 21.5 % | 21.6 % | 21.7 % | 21.8 % | 21.9 % | 22 % |
| 22.1 % | 22.2 % | 22.3 % | 22.4 % | 22.5 % | 22.6 % | 22.7 % | 22.8 % |
| 22.9 % | 23 % | 23.1 % | 23.2 % | 23.3 % | 23.4 % | 23.5 % | 23.6 % |
| 23.7 % | 23.8 % | 23.9 % | 24 % | 24.1 % | 24.2 % | 24.3 % | 24.4 % |
| 24.5 % | 24.6 % | 24.7 % | 24.8 % | 24.9 % | 25 % | 25.1 % | 25.2 % |
| 25.3 % | 25.4 % | 25.5 % | 25.6 % | 25.7 % | 25.8 % | 25.9 % | 26 % |
| Severe anisocytosis | |||||||
| 26.1 % | 26.2 % | 26.3 % | 26.4 % | 26.5 % | 26.6 % | 26.7 % | 26.8 % |
| 26.9 % | 27 % | 27.1 % | 27.2 % | 27.3 % | 27.4 % | 27.5 % | 27.6 % |
| 27.7 % | 27.8 % | 27.9 % | 28 % | 28.1 % | 28.2 % | 28.3 % | 28.4 % |
| 28.5 % | 28.6 % | 28.7 % | 28.8 % | 28.9 % | 29 % | 29.1 % | 29.2 % |
| 29.3 % | 29.4 % | 29.5 % | 29.6 % | 29.7 % | 29.8 % | 29.9 % | 30 % |
| 30.1 % | 30.2 % | 30.3 % | 30.4 % | 30.5 % | 30.6 % | 30.7 % | 30.8 % |
| 30.9 % | 31 % | 31.1 % | 31.2 % | 31.3 % | 31.4 % | 31.5 % | 31.6 % |
| 31.7 % | 31.8 % | 31.9 % | 32 % | 32.1 % | 32.2 % | 32.3 % | 32.4 % |
| 32.5 % | 32.6 % | 32.7 % | 32.8 % | 32.9 % | 33 % | 33.1 % | 33.2 % |
| 33.3 % | 33.4 % | 33.5 % | 33.6 % | 33.7 % | 33.8 % | 33.9 % | 34 % |
| 34.1 % | 34.2 % | 34.3 % | 34.4 % | 34.5 % | 34.6 % | 34.7 % | 34.8 % |
| 34.9 % | 35 % | 35.1 % | 35.2 % | 35.3 % | 35.4 % | 35.5 % | 35.6 % |
| 35.7 % | 35.8 % | 35.9 % | 36 % | 36.1 % | 36.2 % | 36.3 % | 36.4 % |
| 36.5 % | 36.6 % | 36.7 % | 36.8 % | 36.9 % | 37 % | 37.1 % | 37.2 % |
| 37.3 % | 37.4 % | 37.5 % | 37.6 % | 37.7 % | 37.8 % | 37.9 % | 38 % |
| 38.1 % | 38.2 % | 38.3 % | 38.4 % | 38.5 % | 38.6 % | 38.7 % | 38.8 % |
| 38.9 % | 39 % | 39.1 % | 39.2 % | 39.3 % | 39.4 % | 39.5 % | 39.6 % |
| 39.7 % | 39.8 % | 39.9 % | 40 % | 40.1 % | 40.2 % | 40.3 % | 40.4 % |
| 40.5 % | 40.6 % | 40.7 % | 40.8 % | 40.9 % | 41 % | 41.1 % | 41.2 % |
| 41.3 % | 41.4 % | 41.5 % | 41.6 % | 41.7 % | 41.8 % | 41.9 % | 42 % |
| 42.1 % | 42.2 % | 42.3 % | 42.4 % | 42.5 % | 42.6 % | 42.7 % | 42.8 % |
| 42.9 % | 43 % | 43.1 % | 43.2 % | 43.3 % | 43.4 % | 43.5 % | 43.6 % |
| 43.7 % | 43.8 % | 43.9 % | 44 % | 44.1 % | 44.2 % | 44.3 % | 44.4 % |
| 44.5 % | 44.6 % | 44.7 % | 44.8 % | 44.9 % | 45 % | 45.1 % | 45.2 % |
| 45.3 % | 45.4 % | 45.5 % | 45.6 % | 45.7 % | 45.8 % | 45.9 % | 46 % |
| 46.1 % | 46.2 % | 46.3 % | 46.4 % | 46.5 % | 46.6 % | 46.7 % | 46.8 % |
| 46.9 % | 47 % | 47.1 % | 47.2 % | 47.3 % | 47.4 % | 47.5 % | 47.6 % |
| 47.7 % | 47.8 % | 47.9 % | 48 % | 48.1 % | 48.2 % | 48.3 % | 48.4 % |
| 48.5 % | 48.6 % | 48.7 % | 48.8 % | 48.9 % | 49 % | 49.1 % | 49.2 % |
| 49.3 % | 49.4 % | 49.5 % | 49.6 % | 49.7 % | 49.8 % | 49.9 % | 50 % |