Understanding Your Complete Blood Count

As the name suggests, a complete blood count, is a simple blood tests run in an automated or semi-automated machine to tell you about the status of your different blood cells.

So the next question comes isn,what are blood cells. We all have three basic types of blood cells in our bodies. They are the red blood cells, the white blood cells and the platelets. All are formed in bone marrow- the part which is within the bones in our bodies. The synthesis of these cells is orchestrated by a number of factors, some devised within the body and some are acquired from the external sources, the commonest being iron and vitamin B12.

Each cell is assigned a different specific function in the body.

Let's talk about red blood cells first?

The red blood cells, also known as erythrocytes, are biconcave in shape- depressed center with raised edges on both sides- to help them squeeze through narrow spaces of blood vessels in our bodies. The center of these cells have two protein chains, namely, alpha and globin chain. There are different protein chains for the foetus, the children and the adults. The center of this protein structure contains heme- the iron molecule- together forming what we commonly know as hemoglobin. This hemoglobin is what is measured in your CBC. The hemoglobin is responsible for binding to oxygen in the lungs, which we breathe from the air, and release it to different organs throughout our body.

When this hemoglobin level changes, i.e., it becomes low or high, one develops symptoms like tiredness, lethargy, dizziness, hair-fall, brittle nails in the former condition and headaches, flushed skin, rarely blood clots in the latter condition.

The condition of low hemoglobin is called anemia and the condition where there is raised hemoglobin is called polycythemia

Let's now talk about white blood cells aka leucocytes ?

Let's now talk about white blood cells aka leucocytes. These are also formed in the bone marrow as discussed earlier. These are two major types. The first being granulocytes and agranulocytes. Each has a unique function and together they form the primary defence mechanism of our body. These cells are an essential part of our immune system and fight different foreign particles including bacteria, viruses, fungus and allergens. When the total count of these cells is reduced than the normal range, it is called leucopenia and when it is raised, it is known as leucocytosis.

Both have many reasons for each to occur. Simply put, in either of the conditions, your hematologist will look into three different stages of formation of these cells while finding out the reason for their abnormality. The stage at production, that is bone marrow examination, the stage at delivery to the peripheral blood, that is destruction after production and the stage where they get sequestered within spleen or liver.

The last and the tiniest of all, but most talked about cell, in the blood is none other than platelets. The scientific name for this is thrombocyte. It's formation like all other blood cells, happens in the bone marrow through a series of steps. It's aim function is to stop your blood from bleeding by forming a primary clot at the site of bleeding. Ever wondered how after getting a cut in your skin, the bleeding stops on its own. Those are your platelets rising to the occasion and helping you with what they know best, forming a primary clot and assisting the additional clotting factors to form a stronger clot on the scaffold that they have built first. Again too much or too little, like everything else in life, can be problematic. Conditions with high platelet count is known as thrombocytosis and the reverse is known as thrombocytopenia. Yes you guessed it right. The former can cause increased blood clotting, not always though, and the former can increase the risk of bleeding.

Next time when your Hematologist asks for a complete blood count, now you know what is she or he expecting out of the result to help you understand your symptoms and make you feel better.