CBC (includes Differential and Platelets)

Description: A CBC or Complete Blood Count with Differential and Platelets test is a blood test that measures many important features of your blood’s red and white blood cells and platelets. A Complete Blood Count can be used to evaluate your overall health and detect a wide variety of conditions such as infection, anemia, and leukemia. It also looks at other important aspects of your blood health such as hemoglobin, which carries oxygen. 

Also Known As: CBC test, Complete Blood Count Test, Total Blood Count Test, CBC with Differential and Platelets test, Hemogram test  

Collection Method: Blood Draw 

Specimen Type: Whole Blood 

Test Preparation: No preparation required 

When is a Complete Blood Count test ordered?  

The complete blood count (CBC) is an extremely common test. When people go to the doctor for a standard checkup or blood work, they often get a CBC. Suppose a person is healthy and their results are within normal ranges. In that case, they may not need another CBC unless their health condition changes, or their healthcare professional believes it is necessary. 

When a person exhibits a variety of signs and symptoms that could be connected to blood cell abnormalities, a CBC may be done. A health practitioner may request a CBC to help diagnose and determine the severity of lethargy or weakness, as well as infection, inflammation, bruises, or bleeding. 

When a person is diagnosed with a disease that affects blood cells, a CBC is frequently done regularly to keep track of their progress. Similarly, if someone is being treated for a blood condition, a CBC may be performed on a regular basis to see if the treatment is working. 

Chemotherapy, for example, can influence the generation of cells in the bone marrow. Some drugs can lower WBC counts in the long run. To monitor various medication regimens, a CBC may be required on a regular basis. 

What does a Complete Blood Count test check for? 

The complete blood count (CBC) is a blood test that determines the number of cells in circulation. White blood cells (WBCs), red blood cells (RBCs), and platelets (PLTs) are three types of cells suspended in a fluid called plasma. They are largely created and matured in the bone marrow and are released into the bloodstream when needed under normal circumstances. 

A CBC is mainly performed with an automated machine that measures a variety of factors, including the number of cells present in a person's blood sample. The findings of a CBC can reveal not only the quantity of different cell types but also the physical properties of some of the cells. 

Significant differences in one or more blood cell populations may suggest the presence of one or more diseases. Other tests are frequently performed to assist in determining the reason for aberrant results. This frequently necessitates visual confirmation via a microscope examination of a blood smear. A skilled laboratory technician can assess the appearance and physical features of blood cells, such as size, shape, and color, and note any anomalies. Any extra information is taken note of and communicated to the healthcare provider. This information provides the health care provider with further information about the cause of abnormal CBC results. 

The CBC focuses on three different types of cells: 

WBCs (White Blood Cells) 

The body uses five different types of WBCs, also known as leukocytes, to keep itself healthy and battle infections and other types of harm. The five different leukocytes are eosinophiles, lymphocytes, neutrophiles, basophils, and monocytes. They are found in relatively steady numbers in the blood. Depending on what is going on in the body, these values may momentarily rise or fall. An infection, for example, can cause the body to manufacture more neutrophils in order to combat bacterial infection. The amount of eosinophils in the body may increase as a result of allergies. A viral infection may cause an increase in lymphocyte production. Abnormal (immature or mature) white cells multiply fast in certain illness situations, such as leukemia, raising the WBC count. 

RBCs (Red Blood Cells) 

The bone marrow produces red blood cells, also known as erythrocytes, which are transferred into the bloodstream after maturing. Hemoglobin, a protein that distributes oxygen throughout the body, is found in these cells. Because RBCs have a 120-day lifespan, the bone marrow must constantly manufacture new RBCs to replace those that have aged and disintegrated or have been lost due to hemorrhage. A variety of diseases, including those that cause severe bleeding, can alter the creation of new RBCs and their longevity. 

The CBC measures the number of RBCs and hemoglobin in the blood, as well as the proportion of RBCs in the blood (hematocrit), and if the RBC population appears to be normal. RBCs are generally homogeneous in size and shape, with only minor differences; however, considerable variances can arise in illnesses including vitamin B12 and folate inadequacy, iron deficiency, and a range of other ailments. Anemia occurs when the concentration of red blood cells and/or the amount of hemoglobin in the blood falls below normal, resulting in symptoms such as weariness and weakness. In a far smaller percentage of cases, there may be an excess of RBCs in the blood (erythrocytosis or polycythemia). This might obstruct the flow of blood through the tiny veins and arteries in extreme circumstances. 

Platelets 

Platelets, also known as thrombocytes, are small cell fragments that aid in the regular clotting of blood. A person with insufficient platelets is more likely to experience excessive bleeding and bruises. Excess platelets can induce excessive clotting or excessive bleeding if the platelets are not operating properly. The platelet count and size are determined by the CBC. 

Lab tests often ordered with a Complete Blood Count test: 

• Reticulocytes

• Iron and Total Iron Binding Capacity

• Basic Metabolic Panel

• Comprehensive Metabolic Panel

• Lipid Panel

• Vitamin B12 and Folate

• Prothrombin with INR and Partial Thromboplastin Times

• Sed Rate (ESR)

• C-Reactive Protein

• Epstein-Barr Virus

• Von Willebrand Factor Antigen

Conditions where a Complete Blood Count test is recommended: 

• Anemia

• Aplastic Anemia

• Iron Deficiency Anemia

• Vitamin B12 and Folate Deficiency

• Sickle Cell Anemia

• Heart Disease

• Thalassemia

• Leukemia

• Autoimmune Disorders

• Cancer

• Bleeding Disorders

• Inflammation

• Epstein-Barr Virus

• Mononucleosis

Commonly Asked Questions: 

How does my health care provider use a Complete Blood Count test? 

The complete blood count (CBC) is a common, comprehensive screening test used to measure a person's overall health status.  

What do my Complete Blood Count results mean? 

A low Red Blood Cell Count, also known as anemia, could be due many different causes such as chronic bleeding, a bone marrow disorder, and nutritional deficiency just to name a few. A high Red Blood Cell Count, also known as polycythemia, could be due to several conditions including lung disease, dehydration, and smoking. Both Hemoglobin and Hematocrit tend to reflect Red Blood Cell Count results, so if your Red Blood Cell Count is low, your Hematocrit and Hemoglobin will likely also be low. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Differential results mean? 

A low White Blood Cell count or low WBC count, also known as leukopenia, could be due to a number of different disorders including autoimmune issues, severe infection, and lymphoma. A high White Blood Cell count, or high WBC count, also known as leukocytosis, can also be due to many different disorders including infection, leukemia, and inflammation. Abnormal levels in your White Blood Cell Count will be reflected in one or more of your different white blood cells. Knowing which white blood cell types are affected will help your healthcare provider narrow down the issue. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

What do my Platelet results mean? 

A low Platelet Count, also known as thrombocytopenia, could be due to a number of different disorders including autoimmune issues, viral infection, and leukemia. A high Platelet Count, also known as Thrombocytosis, can also be due to many different disorders including cancer, iron deficiency, and rheumatoid arthritis. Results should be discussed with your health care provider who can provide interpretation of your results and determine the appropriate next steps or lab tests to further investigate your health. 

NOTE: Only measurable biomarkers will be reported. Certain biomarkers do not appear in healthy individuals. 

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.

Reflex Parameters for Manual Slide Review

Less than 

Greater Than 

WBC 

1.5 x 10^3 

30.0 x 10^3 

Hemoglobin 

7.0 g/dL 

19.0 g/dL 

Hematocrit 

None 

75%

Platelet 

100 x 10^3 

800 x 10^3 

MCV 

70 fL 

115 fL 

MCH 

22 pg 

37 pg 

MCHC 

29 g/dL 

36.5 g/dL 

RBC 

None 

8.00 x 10^6 

RDW 

None 

21.5

Relative Neutrophil % 

1% or ABNC <500 

None 

Relative Lymphocyte % 

1%

70%

Relative Monocyte % 

None 

25%

Eosinophil 

None 

35%

Basophil 

None 

3.50%

Platelet 

<75 with no flags,

>100 and <130 with platelet clump flag present,

>1000 

Instrument Flags

Variant lymphs, blasts,

immature neutrophils,  nRBC’s, abnormal platelets,

giant platelets, potential interference

The automated differential averages 6000+ cells. If none of the above parameters are met, the results are released without manual review.

CBC Reflex Pathway

Step 1 - The slide review is performed by qualified Laboratory staff and includes:

• Confirmation of differential percentages

• WBC and platelet estimates, when needed

• Full review of RBC morphology

• Comments for toxic changes, RBC inclusions, abnormal lymphs, and other

• significant findings

• If the differential percentages agree with the automated counts and no abnormal cells are seen, the automated differential is reported with appropriate comments

Step 2 - The slide review is performed by qualified Laboratory staff and includes: If any of the following are seen on the slide review, Laboratory staff will perform a manual differential:

• Immature, abnormal, or toxic cells

• nRBC’s

• Disagreement with automated differential

• Atypical/abnormal RBC morphology

• Any RBC inclusions

Step 3 - If any of the following are seen on the manual differential, a Pathologist will review the slide:

• WBC<1,500 with abnormal cells noted

• Blasts/immature cells, hairy cell lymphs, or megakaryocytes

• New abnormal lymphocytes or monocytes

• Variant or atypical lymphs >15%

• Blood parasites

• RBC morphology with 3+ spherocytes, RBC inclusions, suspect Hgb-C,

• crystals, Pappenheimer bodies or bizarre morphology

• nRBC’s

The Complete Blood Count (CBC) with Differential and Platelets Blood Test test contains 1 test with 33 biomarkers. 

Absolute Band Neutrophils

Immature forms of neutrophils are called neutrophilic band cells. Neutrophils are a type of white blood cell that is responsible for much of the body's protection against infection. Neutrophils are produced in the bone marrow and released into the bloodstream to travel to wherever they are needed. Large numbers of immature forms of neutrophils, called neutrophilic band cells, are produced by the bone marrow when the demand is high.

Absolute Basophils

Basophils normally constitute 1% or less of the total white blood cell count but may increase or decrease in certain diseases and are thought to be involved in allergic reactions.

Absolute Blasts

Blasts are immature forms of white blood cells.

Absolute Eosinophils

Eosinophils (eos) respond to infections caused by parasites and play a role in allergic reactions (hypersensitivities)

Absolute Lymphocytes

Lymphocytes are white blood cells that exist in both the blood and the lymphatic system. They are divided into three types. The B lymphocytes (B cells) are antibody-producing cells that are essential for acquired, antigen-specific immune responses. The second type are T lymphocytes (T cells) some T cells help the body distinguish between "self" and "non-self" antigens while others initiate and control the extent of an immune response, boosting it as needed and then slowing it as the condition resolves. Other types of T cells directly attack and neutralize virus-infected or cancerous cells. The third type are natural killer cells (NK cells) that directly attack and kill abnormal cells such as cancer cells or those infected with a virus.

Absolute Metamyelocytes

Metamyelocytes are immature forms of white blood cells.

Absolute Monocytes

Monocytes (mono), similar to neutrophils, move to an area of infection and engulf and destroy bacteria. They are associated more often with chronic rather than acute infections. They are also involved in tissue repair and other functions involving the immune system.

Absolute Myelocytes

Myelocytes are immature forms of white blood cells.

Absolute Neutrophils

Neutrophils (neu) normally make up the largest number of circulating WBCs. They move into an area of damaged or infected tissue, where they engulf and destroy bacteria or sometimes fungi. Young neutrophils, recently released into circulation, are called bands.

Absolute Nucleated Rbc

Nucleated Red Blood Cells (nRBC) ) the presence of NRBCs in the adult blood is usually associated with malignant neoplasms, bone marrow diseases, and other serious disorders.

Absolute Promyelocytes

Promyelocytes are immature forms of white blood cells.

Band Neutrophils

Immature forms of neutrophils are called neutrophilic band cells. Neutrophils are a type of white blood cell that is responsible for much of the body's protection against infection. Neutrophils are produced in the bone marrow and released into the bloodstream to travel to wherever they are needed. Large numbers of immature forms of neutrophils, called neutrophilic band cells, are produced by the bone marrow when the demand is high.

Basophils

Basophils normally constitute 1% or less of the total white blood cell count but may increase or decrease in certain diseases and are thought to be involved in allergic reactions.

Blasts

Blasts are immature forms of white blood cells.

Eosinophils

Eosinophils (eos) respond to infections caused by parasites and play a role in allergic reactions (hypersensitivities)

Hematocrit

Hematocrit is a blood test that measures the percentage of the volume of whole blood that is made up of red blood cells. This measurement depends on the number of red blood cells and the size of red blood cells.

Hemoglobin

Serum hemoglobin is a blood test that measures the level of free hemoglobin in the liquid part of the blood (the serum). Free hemoglobin is the hemoglobin outside of the red blood cells. Most of the hemoglobin is found inside the red blood cells, not in the serum.

Lymphocytes

Lymphocytes are white blood cells that exist in both the blood and the lymphatic system. They are divided into three types. The B lymphocytes (B cells) are antibody-producing cells that are essential for acquired, antigen-specific immune responses. The second type are T lymphocytes (T cells) some T cells help the body distinguish between "self" and "non-self" antigens while others initiate and control the extent of an immune response, boosting it as needed and then slowing it as the condition resolves. Other types of T cells directly attack and neutralize virus-infected or cancerous cells. The third type are natural killer cells (NK cells) that directly attack and kill abnormal cells such as cancer cells or those infected with a virus.

MCH

Mean corpuscular hemoglobin (MCH) is a calculation of the average amount of oxygen-carrying hemoglobin inside a red blood cell.

MCHC

Mean corpuscular hemoglobin concentration (MCHC) is a calculation of the average percentage of hemoglobin inside a red cell.

MCV

Mean corpuscular volume (MCV) is a measurement of the average size of RBCs.

Metamyelocytes

Metamyelocytes are immature forms of white blood cells.

Monocytes

Monocytes (mono), similar to neutrophils, move to an area of infection and engulf and destroy bacteria. They are associated more often with chronic rather than acute infections. They are also involved in tissue repair and other functions involving the immune system.

MPV

Mean Platelet Volume (MPV) - When it indicates average size of platelets are small; older platelets are generally smaller than younger ones and a low MPV may mean that a condition is affecting the production of platelets by the bone marrow. When it indicates a high number of larger, younger platelets in the blood; this may be due to the bone marrow producing and releasing platelets rapidly into circulation.

Myelocytes

Myelocytes are immature forms of white blood cells.

Neutrophils

Neutrophils are a type of white blood cell that is responsible for much of the body's protection against infection. Neutrophils are produced in the bone marrow and released into the bloodstream to travel to wherever they are needed.

Nucleated Rbc

Nucleated Red Blood Cells (nRBC) ) the presence of NRBCs in the adult blood is usually associated with malignant neoplasms, bone marrow diseases, and other serious disorders.

Platelet Count

A platelet count is a test to measure how many platelets you have in your blood. Platelets help the blood clot. They are smaller than red or white blood cells.

Promyelocytes

Promyelocytes are immature forms of white blood cells.

RDW

Red cell distribution width (RDW), which may be included in a CBC, is a calculation of the variation in the size of RBCs.

Reactive Lymphocytes

Lymphocytes are white blood cells that exist in both the blood and the lymphatic system. They are divided into three types. The B lymphocytes (B cells) are antibody-producing cells that are essential for acquired, antigen-specific immune responses. The second type are T lymphocytes (T cells) some T cells help the body distinguish between "self" and "non-self" antigens while others initiate and control the extent of an immune response, boosting it as needed and then slowing it as the condition resolves. Other types of T cells directly attack and neutralize virus-infected or cancerous cells. The third type are natural killer cells (NK cells) that directly attack and kill abnormal cells such as cancer cells or those infected with a virus.

Red Blood Cell Count

An RBC count is a blood test that tells how many red blood cells (RBCs) you have. RBCs contain hemoglobin, which carries oxygen. How much oxygen your body tissues get depends on how many RBCs you have and how well they work.

White Blood Cell Count

A WBC count is a test to measure the number of white blood cells (WBCs) in the blood. WBCs help fight infections. They are also called leukocytes. There are five major types of white blood cells: basophils, eosinophils, lymphocytes (T cells and B cells), monocytes and neutrophils