The CBC consists of a white blood count, which is broken
into components.
The components are lymphocytes, neutrophils, monocytes,
basophils, and eosinophils. Then comes the red blood cell count, hemoglobin,
hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH),
and mean corpuscular hemoglobin concentration (MCHC). Lastly, there is a platelet count.
The CBC is a very important test, and should be done
regularly. It is a key indicator of
what’s going on in your body. Let’s
start with the white blood cells.
They are your body’s army.
They are present to fight off invaders, such as viruses, bacteria, and allergens. When your body is attacked by something
harmful, white blood cells increase and fight off the invader. A high white blood cell count can indicate
infection. Lymphocytes are a type of
white blood cell. They are further
broken down into T cells and B cells.
B-cells make antibodies to attack their enemies. T cells attack cells
that have already been harmed by viruses or cancer. Neutrophils are the most common type of white
blood cell. Their job is to destroy harmful bacteria. Monocytes can be broken down into macrophages
(which “eat” the invader), or dendritic cells. Eosinophils and basophils are
also part of the white blood count, but in a much smaller number. They also help to fight off parasites. Interestingly, when their numbers get too
high, they can contribute to allergies in the body.
As we said earlier, a high white blood cell count usually
means there is an infection somewhere in the body. Other possible reasons for a high white count
could be medication, inflammation (ex: active arthritis), allergic reactions,
blood/ bone marrow disease (leukemia), or severe tissue damage. A low white blood cell count is of equal
importance, and can sometimes be related to HIV/AIDS, autoimmune disorders,
leukemia or other bone marrow disorders, chemotherapy, or some spleen
disorders.
Red blood cells carry oxygen to your cells and remove carbon
dioxide to the lungs where it is eliminated when you exhale. Your hemoglobin is an iron-containing protein
that is responsible for moving the oxygen from the lungs to the body tissues. The hematocrit is the percentage of whole
blood that contains red blood cells. The MCV is the average amount of space
occupied by each red blood cell. MCH is
an estimate of the amount of hemoglobin carried by each red blood cell, and
MCHC is an estimate of the level of hemoglobin in a given number of red blood
cells.
If your red blood cell numbers are normal, that’s
great. There are many reasons for high
red blood cell counts, such as dehydration, kidney disease, bone marrow
disorders, medications, heart, or lung disease.
A low red blood cell count indicates anemia. There can be many reasons for anemia, and
your doctor can help you find it.
Platelets are the component in our blood that stops
bleeding. The platelet cells come
together and form a clot where we need it.
They also act as transport for other blood components. A low platelet count means we might not clot
as well as we should if we get a cut or internal injury. We may even take certain medications that
decrease our platelet counts. We may see
a high platelet count if we have an autoimmune disease or certain cancers,
among other things.
I’m sure you can see why the Complete Blood Count is so important. Having this test is a great way to take control of your health. It should be on your list of regular testing, even when it has been normal all along. If there’s a problem, your doctor will advise you as to the next steps.
