The Red cells, also called red blood cells ou erythrocytes, are the blood cells responsible for transportingoxygen. Specifically, it is the pigment they contain, hemoglobin, which binds to oxygen to bring it to all the cells in the body.

Red blood cells are special cells that lack a nucleus. They are produced in the bone marrow by hematopoietic stem cells and normally live for 120 days, before being destroyed.

They have an easily recognizable “biconcave disc” shape and a red color due to the large amount of hemoglobin they contain.

The number of red blood cells in the blood is normally between 4,5 – 5,5 million / mm³.

This value is evaluated during a blood test called a complete blood count or “complete blood count”.

The interest of this analysis is to detect possible diseases, in particular hematological, infectious, inflammatory or cancerous, or quite simply to make a blood test. It is one of the most prescribed laboratory tests.

The blood count not only measures the number of red blood cells (red blood cells) per mm³blood but also:

• the rate ofhemoglobin
• le mean corpuscular volume (MCV) of red blood cells, the mean corpuscular hemoglobin content (TCMH, which is the average amount of hemoglobin contained in a red blood cell) and the mean corpuscular hemoglobin concentration (CCMH, which is the amount of hemoglobin in 100 ml of red blood cells).
• thehematocrit (proportion of red blood cells to total blood volume)
• the rate of platelets
• the rate of white blood cells (leucocytes)

The shape (morphology) of red blood cells may also be examined. In this case, a microscopic observation is made from a blood smear. Several blood diseases result in an abnormal shape of red blood cells, for example in the shape of a sickle (sickle cell disease), pear or droplet (splenomegaly, etc.), in “target” (hemoglobinosis, thalassemia, etc.) , in a sphere (spherocytosis), in a half-moon, etc.

Size and color abnormalities can also be detected.

A complete blood count (including the number of red blood cells) is taken by taking blood in a medical laboratory.

The morphology of red blood cells is observed under a microscope from a blood smear.

If your results are not completely within the norms, there is no need to worry unnecessarily: variations are normal, and only the doctor will be able to interpret these results and find the corresponding diagnosis.

For information, at man, it is estimated that the normal number of red blood cells is between 4 and 5,7 million per mm3 of blood. At the woman, it is rather between 3,8 and 5,3 million per mm3.

We speak of polycythemia when this number is abnormally high; anemia when it is too low. The causes of anomalies are many and varied.

In addition, possible abnormalities in hemoglobin, MCV, TCMH and CCMH give additional information to guide the diagnosis.

MCV can be decreased (we speak of microcytosis, in certain anemia or iron deficiency) or increased (macrocytosis, for example in the case of cirrhosis).

Finally, abnormalities in the morphology of red blood cells can also provide valuable information to the doctor: other examinations (genetic, for example), could be necessary to make a diagnosis.