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Dr. Betina Chandolia

BDS, MDS - Oral Pathology and Microbiology

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Dr. Ashish Ranjan

MBBS, MD (Pharmacology)

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Complete Blood Count

(CBC)

CBC Test Includes 21 testsView All

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation required

Overview

What is CBC?

A complete blood count (CBC) test is a group of tests that provides information about blood cells like Red Blood Cells (RBC), White Blood Cells (WBC) and platelets. It is routinely performed to provide an overview of a patient's general health status.

Why is CBC done?

To monitor your overall health as part of a routine check-up
To help detect a variety of disorders including infections, anemia, diseases of the immune system, and blood cancers
To monitor an existing blood disorder
To monitor treatment that is known to affect blood cells such as chemotherapy or radiotherapy

What does CBC Measure?

Blood is composed of blood cells suspended in blood plasma (yellowish-colored liquid). The blood cells include red blood cells (also called RBCs or erythrocytes), white blood cells (also called WBCs or leukocytes), and platelets (also called thrombocytes).

Red blood cells (RBCs) are the most abundant blood cells. RBCs contain hemoglobin which helps in the transportation of oxygen to the tissues. RBC count is the measurement of the number of RBCs in a given volume of blood.

Packed Cell Volume (PCV) or Hematocrit (Hct) is the measurement of the blood volume occupied by RBCs. It is expressed in percentage.

White blood cells (WBCs) are key components of the immune system and thus protect the body from various infections and cancers. Total Leucocyte count (TLC) is the measurement of the total number of leukocytes (WBCs) in a given volume of blood.

There are five types of WBCs:

Neutrophils
Basophils
Eosinophils
Lymphocytes
Monocytes

Differential Leucocyte Count (DLC) determines the percentage of different types of WBCs.

Neutrophils, Basophils, and Eosinophils are called Granulocytes because of the presence of granules inside these cells.

Absolute count of different types of WBCs is the measurement of their absolute numbers in the given volume of blood.

Platelet count - Platelets (also called thrombocytes) are disc-shaped cell fragments without a nucleus that help in blood clotting. Platelet count is the measurement of the number of platelets in a given volume of blood.

Mean Platelet Volume (MPV) is a measurement of the average size of platelets.

PDW or platelet distribution width refers to the variation of platelet size distribution

Hemoglobin (Hb) - Hemoglobin (Hb) is a protein found in red blood cells (RBCs) that carries oxygen from the lungs to the body tissues, exchanges the oxygen for carbon dioxide, and then carries the carbon dioxide back to the lungs where it is exchanged for oxygen.

Mean Corpuscular Volume (MCV) is the average volume of a red blood cell.

Mean Corpuscular Hemoglobin (MCH) is the average amount of hemoglobin in the average red blood cell.

Mean Corpuscular Hemoglobin Concentration (MCHC) is the average concentration of hemoglobin in a given volume of red cells.

Red Cell Distribution Width Coefficient of variation (RDW CV)is a measurement of the variability of the red blood distribution curve and their mean size.

Interpreting CBC results

Interpretations

Meaning of Abnormal CBC Test Results

Hemoglobin

Decreased levels - Anemia

Increased levels - Polycythemia

Decreased levels - Aplastic anemia, Bone marrow disorders, Autoimmune conditions
Increased levels - Infections, Inflammatory disorders, Leukemia, Myeloproliferative disorders

Neutrophil count

Decreased levels (Neutropenia) - Aplastic anemia, Autoimmune disorders, Drug reactions or Chemotherapy
Increased levels (Neutrophilia) - Acute bacterial infections, Inflammation, Burns

Lymphocyte count

Decreased levels (Lymphopenia) - Bone marrow damage, Aplastic anemia, Autoimmune disorders
Increased levels (Lymphocytosis) - Acute viral infections, Tuberculosis, Lymphocytic leukemia

Monocyte count

Decreased levels - Bone marrow damage
Increased levels (Monocytosis) - Chronic infections like tuberculosis, Bacterial endocarditis, Collagen vascular disorders, Inflammatory bowel diseases

Eosinophil count

Decreased levels - Rare and medically insignificant
Increased levels (Eosinophilia) - Asthma, Allergies, Drug reactions, Parasitic infections

Basophil count

Decreased levels - Medically insignificant
Increased levels (Basophilia) - Chronic myeloid leukemia (CML)

Platelet count

Decreased levels (Thrombocytopenia) - Viral infections like dengue fever, bleeding or platelet disorders
Increased levels (Thrombocytosis) -Blood Loss, Chronic Infection or Inflammatory Disease, Removal of the spleen

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about CBC

Frequently Asked Questions about Complete Blood Count

Q. Is there any risk associated with this test?

There is no risk associated with the test. However, since this test involves a needle prick to withdraw the blood sample, in very rare cases, a patient may experience increased bleeding, hematoma formation (blood collection under the skin), bruising or infection at the site of needle prick.

Q. How is the CBC test performed?

A healthcare professional will draw a blood sample from a vein in the arm or a finger-prick or heel-prick (newborns). Unless specified by the doctor, there is no special preparation required before the test.

Q. What the CBC test results may indicate?

A Complete blood count (CBC) is not a definitive diagnostic test. Blood cell counts that are too high or too low could signal a wide variety of conditions. Specialized tests are needed to diagnose a specific condition. Your doctor may prescribe more tests to find out the underlying disease

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Tests Included (21 tests)

RDW CV
Hematocrit
Total Leucocyte Count
Absolute Lymphocyte Count
Hemoglobin
Absolute Neutrophil Count
Mean Corpuscular Hemoglobin
Absolute Basophil Count
Differential leucocyte Count(includes 5 tests)
Differential Monocyte Count
Differential Neutrophil Count
Differential Lymphocyte Count
Differential Eosinophil Count
Differential Basophil Count
Red Blood Cell Count
Mean Corpuscular Volume
Mean Corpuscular Hemoglobin Concentration
PDW
Mean Platelet Volume
Absolute Eosinophil Count
Platelet Count
Absolute Monocyte Count