What is Anisocytosis?

What is Anisocytosis?

Anisocytosis is the medical term used to refer to having different-sized red blood cells (RBC) which can be diagnosed by taking a blood test. This condition is regarded as an abnormality in the blood that is usually caused by some form of anaemia. At oneHOWTO we explain in detail what is anisocytosis and what is the normal range of red blood cell size.

Which does Red Blood Cell Distribution Width (RDW) mean?

RDW stands for red cell distribution width and it is the range used to indicate if you have anisocytosis by the percentage shown in your blood test. A high RDW percentage means you have a large number of different-sized red blood cells in your blood. This commonly affects people who have an iron deficiency which reduces haemoglobin production, causing the red blood cells to be smaller than normal.

Reference range for RDW

A normal RDW value ranges between 11.5% and 14.5%. Any value outside of this may be due to:

  • Haemolytic anaemia
  • Folic acid deficiency anaemia
  • Iron deficiency anaemia
  • Pernicious anaemia
  • Sickle cell anaemia
  • Alcoholism

Find out what the symptoms for anemia are in this oneHOWTO article.

Mean cell volume

Mean cell volume known as MCV is the value that indicates the average volume of red blood cells, which must be between 78 - 100 fL. This value is always compared with your RDW value as it is necessary to take both into account in order to diagnose your condition.

If the MCV value is high it means that your red blood cells are larger than normal. On the other hand, if the MCV is low it indicates that your red blood cells are smaller than usual.

If you have a normal RDW and a low MCV you could be at risk of suffering from a chronic disease such as chronic anaemia or rheumatoid arthritis. If both values are low, you may have an iron deficiency. That said, you can still be at risk of having a chronic disorder even if both values are normal. If your RDW is normal but your MCV is high, you could have a vitamin B12 deficiency, and if they are both high you could have a folic acid deficiency.

Whatever your blood test values, it is recommended to see a haematologist for a full examination.

This article is merely informative, oneHOWTO does not have the authority to prescribe any medical treatments or create a diagnosis. We invite you to visit your doctor if you have any type of condition or pain.

If you want to read similar articles to What is Anisocytosis?, we recommend you visit our Diseases & secondary effects category.