VCM is the Average Corpuscular Volume and indicates the average size of red blood cells, also known as red blood cells. Its calculation helps in the diagnosis of some diseases, such as anemia.
The VCM index is measured per unit of phentoliter (fL) and its analysis is performed on the Hemogram, within the group of hematimetric indices.
The function of red blood cells and their importance to our body
Blood cells, together with platelets, have a large-scale representation in the blood composition: about 47%. They are red blood cells and circulate through blood vessels, such as arteries, which carry blood from the heart to the tissues of the body and organs, and the veins, which in the conduction process, make the inverse path of the arteries.
Microscopic image of red blood cells (RBCs).
Red blood cells have in their composition iron and hemoglobin: responsible for the red color of blood. and its main function is to transport gases, especially oxygen, to cells throughout the body.
Learn more about red blood cells and its importance for the functioning of our body.
Interpreting VCM indices in the Hemogram
The Hemogram is a blood test responsible for analyzing the indices of red blood cells, leukocytes and platelets. diagnose diseases that affect the composition of the blood, such as: anemia, leukemia, hemorrhage, bacterial infections and allergies.
Within the entire analysis of the Hemogram, we find the VCM, in charge of pointing out possible changes that indicate the increase or decrease of red blood cells, causing some types of disorders, if your index is changed.
normal VCM
Reference indices for a VCM may vary by laboratory. However, for the most part, the normal value is between 80 and 100 fL (phentoliter) in adults.
The normal VCM index indicates that the red blood cells are in their regular size and fulfilling their functions correctly.
Check out the basic VCM reference numbers by age below:
| Newborns | 77.0 to 101.0 fl |
babies up to one year old |
77.0 to 95.0 fl |
| Children over 10 years old | 80.0 to 100.0 fl |
| old women | 80.0 to 100.0 fl |
| adult men | 80.0 to 100.0 fl |
High VCM: what can it be?
When the VCM is high, that is, it exceeds the value of 96 fL, it indicates that the red blood cells are large, indicating an anisocytosis: a disproportion in the size of blood cells.
The high value of VCM can indicate two types of macrocytic anemia: pernicious megaloblastic, when the gastrointestinal tract cannot absorb vitamin B12, or megaloblastic vitamin B12 deficiency, which occurs when the individual does not eat foods that contain the b12 vitamin.
In addition to indicating a possible anemia, the high level of VCM also occurs when the individual is dependent on alcoholic beverages, or has myelodysplastic syndrome and hypothyroidism.
Learn more about anisocytosis.
Low VCM: what can it be?
A low VCM, ie less than 80 fL, indicates that the size of red blood cells is reduced, diagnosing microcytic anemia such as iron deficiency, which is caused by iron deficiency, pointing to the need to change eating habits, with the intake of foods rich in iron.
RDW and its importance in calculating VCM
RDW stands for Red Cell Distribution Width, which in Portuguese means Distribution Amplitude of Red Blood Cells, and its function is to assess anisocytosis: variation in cell size red.
The RDW works as a standard deviation of the VCM, because if a patient has increased and decreased red blood cells at the same time, his VCM index on the blood count may be normal.
Thus, the RDW can indicate possible diseases such as anemia, diabetes and liver problems, even if the VCM value is normal compared to the reference numbers.
Learn about the meaning and types of Anemia.