HematologyHematology

TC & DC (Total Count & Differential Count)

Normal Range
4,000-11,000 (TC), Neutrophils: 40-75%, Lymphocytes: 20-45%
Sample Type
Whole Blood
Fasting
No
Unit
cells/mcL

Function

The Total Count (TC) refers to the total number of White Blood Cells (WBCs/Leukocytes) in the blood, while the Differential Count (DC) breaks down these cells into five main types: Neutrophils, Lymphocytes, Monocytes, Eosinophils, and Basophils. These cells are the backbone of the immune system, defending the body against infections, foreign invaders, and abnormal cell growth.

Why it is Ordered

This is one of the most frequently ordered tests because it provides a snapshot of the body's immune status. It is used to:

  • Detect infection (bacterial, viral, or parasitic).
  • Evaluate bone marrow function.
  • Monitor the effects of chemotherapy or radiation.
  • Investigate inflammatory conditions or allergic reactions.

Associated Conditions

  • Leukocytosis (High TC): Often caused by acute infections, inflammation, or leukemia.
  • Leukopenia (Low TC): Seen in viral infections (like HIV), bone marrow failure, or certain drug toxicities.
  • Neutrophilia: Specifically suggests bacterial infection.
  • Lymphocytosis: Suggests viral infection (e.g., Mononucleosis) or chronic lymphocytic leukemia.
  • Eosinophilia: Associated with allergies, asthma, or parasitic infections.

Panel Components

This test is a profile comprising the following specific markers:

Lymphocytes
%
Total Leucocyte Count (WBC)
cells/µL
Neutrophils
%
Monocytes
%
Basophils
%
Eosinophils
%

Why Context Matters

WBC counts are highly dynamic and can be elevated by non-medical factors such as strenuous exercise, smoking, emotional stress, or pregnancy. Corticosteroid medications significantly increase the neutrophil count while decreasing the lymphocyte count. A second opinion is often required to look at a peripheral blood smear (manual differential) if the automated counter detects 'blasts' or 'immature cells' which could indicate malignancy vs. a simple infection.

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

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.

Get Notified When Dr. Babu Is Available