A Red Cell Distribution Width (RDW) blood test measures how much the volume and size of your red blood cells (erythrocytes) vary. This test is often performed as part of a complete blood count (CBC). An RDW test can help your healthcare provider diagnose and determine the causes of certain conditions, such as anemia or other blood disorders.
Here are some key points about RDW:
- What it measures: RDW measures the variation in the size of red blood cells.
- Why it's important: A high RDW can indicate that there is a problem with the production of red blood cells.
- How it's used: Along with other tests, an RDW blood test can help diagnose anemia, iron deficiency, vitamin B12 deficiency, folate deficiency, chronic liver disease, and other conditions.
Examples of how RDW results are interpreted:
- High RDW and typical MCV (Mean Corpuscular Volume): This combination suggests an iron, vitamin B12, or folate deficiency or possibly chronic liver disease.
- High RDW and low MCV: This combination could indicate thalassemia, a genetic blood disorder.
Note: The normal range for RDW varies depending on the laboratory, but is typically between 11.8% and 14.5% for adult males and 12.2% and 16.1% for adult females.
