What is a Complete Blood Count test?
The human body is primarily made up of water and cells. Many of the cells group together to form the skin, muscles, bones and organs, such as the heart, lungs, kidneys, etc. Such cells are stationary, staying in one place within the body.
Some very special and important cells, however, move throughout the body by traveling (circulating) in the blood. These circulating cells provide oxygen to all the stationary cells in the body, help fight infection throughout the body, and help stop bleeding after an injury. Information about these cells can provide important clues about the overall health of the body.
A Complete Blood Count (CBC) test is a very common test that screens for certain disorders that can affect your health. A CBC measures the amount and types of cells in your blood and can be used to determine if there are any increases or decreases in your cell counts. Measuring changes in your blood cell levels can help your doctor evaluate your overall health.
Blood contains red blood cells (RBC), white blood cells (WBC), and platelets. Specific types of tests include:
A CBC test usually includes:
- White blood cell (WBC) count and cell types (WBC differential)
- White blood cells protect the body against infection
- The major types of white blood cells are neutrophils, lymphocytes, monocytes, eosinophils, and basophils
- If an infection develops, the number of white blood cells rises rapidly to attack and destroy the bacteria, virus, or other organism causing it
- Too many or too few of the different types of white blood cells can help find an infection, an allergic or toxic reaction to medicines or chemicals, and many other conditions
- Red blood cell (RBC) count
- Red blood cells carry oxygen from the lungs to the rest of the body and carbon dioxide back to the lungs so it can be exhaled
- A low RBC count is called anemia, and can mean that the body may not be getting the oxygen it needs
- A high RBC count is called polycythemia, and indicates a chance that the red blood cells will clump together and block tiny blood vessels (capillaries)
- Platelet count and Mean Platelet Volume (MPV)
- Platelets are important in blood clotting
- When bleeding occurs, the platelets swell, clump together, and form a sticky plug that helps stop the bleeding
- MPV measures the average amount (volume) of platelets
- Hemoglobin (Hgb), Mean Corpuscular Hemoglobin (MCH), and Mean Corpuscular Hemoglobin Concentration (MCHC)
- Hemoglobin carries oxygen and gives the blood cell its red color
- The Hemoglobin (Hgb) test measures the amount of hemoglobin in blood and is a good measure of our ability to carry oxygen throughout the body
- The Mean Corpuscular Hemoglobin (MCH) value is the amount of hemoglobin in an average red blood cell
- The Mean Corpuscular Hemoglobin Concentration (MCHC) measures the concentration of hemoglobin in an average red blood cell
- Hematocrit (HCT)
- This measures the volume that red blood cells take up in the blood
- It which is demonstrated as a percentage (i.e., a hematocrit of 38 means that 38% of the blood’s volume is made of red blood cells)
- Reticulocyte count
- Reticulocytes are immature red blood cells that are made in the bone marrow and subsequently released into the bloodstream
- After approximately 2 days, reticulocytes develop into mature red blood cells
- The reticulocyte count test measures how fast they are made and released into the blood
- Mean Corpuscular Volume (MCV)
- The MCV shows the size of the red blood cells
A CBC test may be done to help doctors check on overall health, so your doctor may order this test as a part of your yearly physical. These tests can also help to diagnose conditions such as anemia, infections, clotting problems, blood cancers, and immune disorders.
When will I receive my results?
Once completed, you will receive your results within 3-5 business days in your LabFinder portal.
How do I prepare? Do I need to fast?
No preparation or fasting required. Just bring your LabFinder Order and Insurance Card to your appointment.