HematologyHematology

Complete Blood Picture

Normal Range
WBC: 4.5-11.0, RBC: 4.5-5.9 (M), Plt: 150-450
Sample Type
Whole Blood
Fasting
No
Unit
Mixed

Function

The Complete Blood Picture (CBP), also known as a Complete Blood Count (CBC), is one of the most fundamental blood tests in clinical medicine. It evaluates the three major types of cells circulating in the blood: Red Blood Cells (RBCs) which carry oxygen, White Blood Cells (WBCs) which fight infection, and Platelets (PLTs) which assist in blood clotting. It also includes indices like MCV and MCH that describe the size and hemoglobin content of RBCs.

Why it is Ordered

CBP is the first-line test for almost any physical complaint. It is used to diagnose anemia, monitor patients undergoing chemotherapy, screen for leukemia, check for infections, and evaluate the cause of unexplained bruising or weakness.

Associated Conditions

  • Anemia: Low RBC count or Hemoglobin, often causing fatigue.
  • Leukemia: Malignant overproduction of abnormal white blood cells.
  • Thrombocytopenia: Low platelet count, increasing the risk of spontaneous bleeding.
  • Polycythemia: Overproduction of red blood cells, which can thicken the blood.
  • Infection: Indicated by a high WBC count (Leukocytosis).

Panel Components

This test is a profile comprising the following specific markers:

Mean Corpuscular Hemoglobin (MCH)
pg
Neutrophils (Absolute)
10^9/L
Basophils (Absolute)
10^9/L
Hematocrit (Hct)
%
Platelet Count
10^9/L
Eosinophils (Absolute)
10^9/L
Mean Corpuscular Volume (MCV)
fL
Mean Corpuscular Hemoglobin Concentration (MCHC)
g/dL
Monocytes (Absolute)
10^9/L
Lymphocytes (Absolute Count)
10^9/L
White Blood Cell Count (WBC)
10^9/L
Hemoglobin (Hb)
g/dL
Red Blood Cell Count (RBC)
10^12/L
Red Cell Distribution Width (RDW)
%

Why Context Matters

CBP results can be influenced by many factors including high altitude (increases RBCs), pregnancy (dilutes RBCs), and vigorous exercise (temporarily spikes WBCs). Additionally, 'pseudothrombocytopenia' can occur if the blood sample clots slightly in the tube, giving a falsely low platelet reading. A second opinion/smear review is necessary if results do not match the clinical picture.

Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.

Clinical References

Source-of-truth databases and clinical guidelines for Complete Blood Picture:

Research & Guidelines

Related Indicators

Activated Partial Thromboplastin Time (APTT)

View Range

Blood Cell Morphology

View Range

AML Comboquest 9

View Range
DR

Medically Reviewed by Dr. Binoy Babu, MBBS

Board Certified Doctor • 10+ Years Clinical Experience

Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.

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