Edwin Cyril A. Libre July 11, 2010 Group A4 Ma’am Banluta

A complete blood count (CBC), also known as full blood count (FBC) or full blood exam (FBE) or blood panel, is a test panel requested by a doctor or other medical professional that gives information about the cells in a patient's blood. A scientist or lab technician performs the requested testing and provides the requesting medical professional with the results of the CBC.

Alexander Vastem is widely regarded as being the first person to use the complete blood count for clinical purposes. Reference ranges used today stem from his clinical trials in the early 1960s.

The cells that circulate in the bloodstream are generally divided into three types: white blood cells (leukocytes), red blood cells (erythrocytes), and platelets (thrombocytes). Abnormally high or low counts may indicate the presence of many forms of disease, and hence blood counts are amongst the most commonly performed blood tests in medicine, as they can provide an overview of a patient's general health status. A CBC is routinely performed during annual physical examinations in some jurisdictions.

Samples

A phlebotomist collects the specimen, in this case blood is drawn in a test tube containing an anticoagulant (EDTA, sometimes citrate) to stop it from clotting, and transported to a laboratory.

In the past, counting the cells in a patient's blood was performed manually, by viewing a slide prepared with a sample of the patient's blood under a microscope (a blood film, or peripheral smear). Nowadays, this process is generally automated by use of an automated analyzer, with only approximately 30% samples now being examined manually.

Red cells

Total red blood cells - The number of red cells is given as an absolute number per litre.

Hemoglobin - The amount of hemoglobin in the blood, expressed in grams per decilitre. (Low hemoglobin is called anemia.)

Hematocrit or packed cell volume (PCV) - This is the fraction of whole blood volume that consists of red blood cells.

Red blood cell indices o Mean corpuscular volume (MCV) - the average volume of the red cells,

measured in femtolitres. Anemia is classified as microcytic or macrocytic based on whether this value is above or below the expected normal range.

Other conditions that can affect MCV include thalassemia and reticulocytosis.

o Mean corpuscular hemoglobin (MCH) - the average amount of hemoglobin per red blood cell, in picograms.

o Mean corpuscular hemoglobin concentration (MCHC) - the average concentration of hemoglobin in the cells.

Red blood cell distribution width (RDW) - a measure of the variation of the RBC

White cells

Total white blood cells - All the white cell types are given as a percentage and as an absolute number per litre.

A complete blood count with differential will also include:

Neutrophil granulocytes - May indicate bacterial infection. May also be raised in acute viral infections.Because of the segmented appearance of the nucleus, neutrophils are sometimes referred to as "segs." The nucleus of less mature neutrophils is not segmented, but has a band or rod-like shape. Less mature neutrophils - those that have recently been released from the bone marrow into the bloodstream - are known as "bands" or "stabs". Stab is a German term for rod.[1]

Lymphocytes - Higher with some viral infections such as glandular fever and. Also raised in lymphocytic leukemia CLL. Can be decreased by HIV infection. In adults, lymphocytes are the second most common WBC type after neutrophils. In young children under age 8, lymphocytes are more common than neutrophils.[2].

Monocytes - May be raised in bacterial infection, tuberculosis, malaria, Rocky Mountain spotted fever, monocytic leukemia, chronic ulcerative colitis and regional enteritis [3]

Eosinophil granulocytes - Increased in parasitic infections, asthma, or allergic reaction.

Basophil granulocytes- May be increased in bone marrow related conditions such as leukemia or lymphoma. [4]

A manual count will also give information about other cells that are not normally present in peripheral blood, but may be released in certain disease processes.

Platelets

Platelet numbers are given, as well as information about their size and the range of sizes in the blood.

Interpretation

Certain disease states are defined by an absolute increase or decrease in the number of a particular type of cell in the bloodstream. For example:

Type of Cell Increase Decrease

Red Blood Cells (RBC)erythrocytosis or polycythemia

anemia or erythroblastopenia

White Blood Cells (WBC):

leukocytosis leukopenia

-- lymphocytes -- lymphocytosis -- lymphocytopenia

-- granulocytes: -- granulocytosis-- granulocytopenia or agranulocytosis

-- --neutrophils -- --neutrophilia -- --neutropenia-- --eosinophils -- --eosinophilia -- --eosinopenia-- --basophils -- --basophilia -- --basopeniaPlatelets thrombocytosis thrombocytopeniaAll cell lines - pancytopenia

Many disease states are heralded by changes in the blood count:

leukocytosis can be a sign of infection. thrombocytopenia can result from drug toxicity. pancytopenia is generally as the result of decreased production from the bone

marrow, and is a common complication of cancer chemotherapy.

Normal Values:

TEST NORMAL VALUES

Leukocyte (White Blood Cell) X1000 cells/mm³ (µL)

Birth 9.0-30.0

24 hours 9.4-34.0

1 month 5.0-19.5

1-3 years 6.0-17.5

4-7 years 5.5-15.5

8-13 years 4.5-13.5

Adult 4.5-11.0

Neutrophils Bands 3-5% (total WBC count)

Segs 54-62%

Lymphocytes 25-33%

Monocytes 3-7%

Eosinophils 1-3%

Basophils 0-0.75%

Erythrocytes (Red Blood Cells)

Cord 3.9-5.5 million/mm³

1-3 days 4.0-6.6 million/mm³

1 week 3.9-6.3 million/mm³

2 weeks 3.6-6.2 million/mm³

1 month 3.0-5.4 million/mm³

2 months 2.7-4.9 million/mm³

3-6 months 3.1-4.5 million/mm³

0.5-2 years 3.7-5.3 million/mm³

2-6 years 3.9-5.3 million/mm³

6-12 years 4.0-5.2 million/mm³

12-18 years (male) 4.5-5.3 million/mm³

12-18 years (female) 4.1-5.1 million/mm³

Hemoglobin

1-3 days 14.5-22.5 g/dL

2 months 9.0-14.0 g/dL

6-12 years 11.5-15.5 g/dL

12-18 years (male) 13.0-16.0 g/dL

12-18 (female) 12.0-16.0g/dL

Hematocrit

1 day 48-69%

2 days 48-75%

3 days 44-72%

2 months 28-42%

6-12 years 35-45%

12-18 years (male) 37-49%

12-18 years (female) 36-46%

Mean Corpuscular Volume (MCV)

1-3 days 95-121µm³

0.5-2 years 70-86 µm³

6-12 years 77-95 µm³

12-18 years (male) 78-98 µm³

12-18 years (female) 78-102 µm³

Mean Corpuscular Hemoglobin (MCH)

Birth 31-37 pg/cell

1-3 days 31-37 pg/cell

1 week-1 month 28-40 pg/cell

2 months 26-34 pg/cell

3-6 months 25-35 pg/cell

0.5-2 years 23-31 pg/cell

2-6 years 24-30 pg/cell

6-12 years 25-33 pg/cell

12-18 years 25-35 pg/cell

Mean Corpuscular Hemoglobin Concentration (MCHC)

Birth 30-36 g Hg/dL RBC

1-3 days 29-37 g Hg/dL RBC

1-2 weeks 28-38 g Hg/dL RBC

1-2 months 29-37 g Hg/dL RBC

3 months-2 years 30-36 g Hg/dL RBC

2-18 years 31-37 g Hg/dL RBC

Reticulocyte Count

Infants 2-5% of RBCs

Children 0.5-4% of RBCs

12-18 years (male) 0.5-1% of RBCs

12-18 years (female) 0.5-2.5% of RBCs

Platelet Count

Birth-1 week 84,000-478,000/mm³

Thereafter 150,000-400,000/mm³

ERYTHROCYTE SEDIMENTATION RATE (ESR)

TEST NORMAL VALUE

Westergren

Child 0-10 mm/hour

Adult (male) 0-15 mm/hour

Adult (female) 0-20 mm/hour

Wintrobe

Child 0-13 mm/hour

Adult (male) 0-9 mm/hour

Adult (female) 0-20 mm/hour