Understanding the Haemogram: How to Interpret Your Blood Test Results

By Global Health GP Insights

A haemogram, commonly known as a complete blood count (CBC), is one of the most frequently requested blood tests in both routine check-ups and diagnostic investigations. It provides crucial information about your overall health by evaluating the different types of cells in your blood. This simple test can help identify infections, allergies, inflammation, immune system disorders, and even early signs of more serious illnesses.

🩸 What Is a Haemogram?

A haemogram measures various components of blood, including:

• Red blood cells (RBCs)

• White blood cells (WBCs)

• Platelets

• Haemoglobin

• Haematocrit

  
  

However, in this article we will focus specifically on white blood cells (leukocytes) and their subtypes, since they are critical indicators of immune response and often highlighted in clinical interpretations.

🔬 White Blood Cell Types and Their Clinical Meaning

Your body produces five main types of white blood cells, and an increase or decrease in each type can signal different health conditions:

Cell Type	Function	Cause of Elevated Level
Neutrophils	First responders to bacterial infection	🔺 Infections
Eosinophils	Fight parasites, involved in allergic responses	🔺 Parasitic infections, allergies
Lymphocytes	Fight viruses, regulate immune response	🔺 Viral infections
Basophils	Release histamine in allergic reactions	🔺 Allergies
Monocytes	Remove dead cells, fight chronic infections	🔺 Inflammations, autoimmune issues

📊 Normal Reference Ranges (Adult)

Although reference ranges may slightly vary by lab, the typical values are:

• Neutrophils: 40–60% of total WBCs

• Eosinophils: 1–4%

• Lymphocytes: 20–40%

• Basophils: 0.5–1%

• Monocytes: 2–8%

  
  

A deviation from these values might not always indicate disease, but it does require interpretation by a qualified healthcare provider in the context of symptoms, history, and other test results.

🧬 What Does It Mean If One of These Values Is Elevated?

• High Neutrophils: Often suggest bacterial infections or physical stress (e.g., surgery, trauma).

• High Eosinophils: Typically linked to parasitic infections, allergies, or autoimmune disorders.

• High Lymphocytes: May occur with viral infections like flu, hepatitis, or mononucleosis.

• High Basophils: Rare but can be associated with chronic allergies, inflammation, or certain blood disorders.

• High Monocytes: Seen in chronic infections like tuberculosis or inflammatory diseases.

🩺 Why Is This Important?

Knowing how to read your haemogram can help you:

• Detect infections early

• Monitor chronic diseases

• Understand allergic responses

• Evaluate your immune system’s health

  
  

If your blood test shows abnormal levels in any of these white blood cell types, it's essential to consult your healthcare provider for a full interpretation and next steps.