What is a CBC
Page 1: Introduction
What is a CBC (Complete Blood Count)?
An essential blood test providing crucial health information.
Course Code: MLT1304
Date: January 2025
Page 2: CBC Results Overview
Sample Comments: Metal overall status indicator.
Sysmex XN-1000 Results: Details various blood components measured, such as:
WBC (White Blood Cells): 9.04 [10/UL]
RBC (Red Blood Cells): 3.84 [10/UL]
HGB (Hemoglobin): 11.0 [g/dL]
HCT (Hematocrit): 32.3 [%]
MCV (Mean Corpuscular Volume): 84.1 [fL]
MCH, MCHC, PLT: Regulating blood components and their average concentration and volume.
Various other parameters (e.g., MPV, RDW.
Page 3: White Blood Cells (WBC)
White Blood Count Numbers for Adults:
Normal range: 4.0-11.0 x 10^9 /L.
Increased Values: Bacterial infections, leukemias.
Decreased Values: Viral infections.
Types of WBC:
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
Lifespan Variability: Neutrophils live for hours; memory lymphocytes can live for years; most live for days.
Page 4: Red Blood Cells (RBC)
RBC Normal Values:
Males: 4.7–6.1 × 10^12/L.
Females: 4.2–5.4 × 10^12/L.
Also known as erythrocytes.
Function: Deliver oxygen to tissues.
Structure: Bi-concave discs containing hemoglobin.
Lifespan: Circulate for approximately 120 days.
Page 5: Hemoglobin (HGB)
Normal Hemoglobin Levels:
Males: 140–180 g/L
Females: 120–160 g/L
Function: Carries oxygen to tissues, transports carbon dioxide back to lungs.
Low levels indicate anemia.
Page 6: Hematocrit (HCT)
Normal Values:
Males: 0.42–0.52
Females: 0.37–0.47
HCT is a calculated parameter.
Rule of Three:
Correlation check between Hgb and Hct.
Formulas:
RBC × 3 = Hgb
Hgb × 3 = Hct ± 3.
Page 7: Mean Corpuscular Volume (MCV)
Importance:
Measures average red blood cell size.
Normal Range: 80-100 fL.
Low MCV Causes: Iron deficiency anemia, thalassemia.
High MCV Causes: Megaloblastic anemia, alcoholism.
Calculation: MCV = (Hct ÷ RBC) × 1000.
Page 8: Mean Corpuscular Hemoglobin (MCH)
Description: Average amount of hemoglobin in a single RBC.
Normal Range: 27–31 pg.
Calculation: MCH = (Hgb ÷ RBC).
Page 9: Mean Corpuscular Hemoglobin Concentration (MCHC)
Description: Average concentration of hemoglobin within RBCs.
Normal Range: 320-360.
High MCHC Causes: Spherocytosis, hemolytic anemia.
Differences: Can show false positives in cold agglutinin diseases.
Page 10: Platelet Count (PLT)
Normal Range: 150–450 × 10^9/L.
Critical Values:
Low: 20.0 × 109/L
High: 1,000 × 109/L.
Function: Begin clotting process.
Low Values: Associated with diseases like ITP, TTP.
Page 11: Red Cell Distribution Width (RDW)
Normal Range: 11.5%–14.5%.
First indication of anemia.
Measurement: Variation in volume and size of erythrocytes.
High RDW: Indicative of anisocytosis, particularly in transfused patients.
Page 12: Mean Platelet Volume (MPV)
Description: Average size of platelets in blood.
High MPV: Indicates large or giant platelets.
Page 13: Neutrophils (%NEUT)
Definition: Relative neutrophil count, expressed as a percentage.
Function: Critical role in fighting infection.
Range: 40-70% of total WBCs.
Page 14: Lymphocytes (%LYMPH)
Function: Essential component of the immune system, assists in infection defense.
Increased in viral infections.
Normal Range: 20-40%.
Page 15: Monocytes (%MONO)
Function: Fights infections and helps in cellular waste removal.
Normal Range: 2-8%.
These cells differentiate into macrophages.
Page 16: Eosinophils (%EO)
Function: Responds to parasitic infections and allergies.
Normal Range: 1-4%.
High levels indicate parasitic infections, allergic reactions, or cancers.
Page 17: Basophils (%BASO)
Description: Least common type of granulocyte.
Normal Range: 0.5-1%.
Function: Fights bacterial, fungal infections.
Page 18: Absolute Counts of WBC
Concept: Combination of relative and absolute counts in WBC differential.
Relative Count: Percentage from 100-cell count.
Absolute Count: True distribution, calculated by multiplying WBC percentage by total WBC count.
Page 19: Absolute Count Calculation
Example Calculation:
Given WBC = 5.0 × 10^9/L:
Segmented Neutrophils: 40% → 2.0
Bands: 3% → 0.15
Lymphocytes: 55% → 2.75
Monocytes: 2% → 0.1
Validation: Sum must equal total WBC (2.0 + 0.15 + 2.75 + 0.1 = 5.0).