White Blood Cell Differential Count (with Absolute Counts)
This test measures the types and amounts of white blood cells in your blood, including neutrophils, lymphocytes, monocytes, eosinophils, and basophils, along with their absolute counts.
["Understanding your immune cell composition helps identify infections, inflammation, or other health conditions."]
Key facts at a glance
- LOINC
- 26467-1
- Short code
- WBC # Plr
- Synonyms
- WBC # Plr
- Category
- chemistry
- Sample
- fluid
- Container
- Sterile tube
- Units
- N/A
- Ref low
- 4.5
- Ref high
- 11
- Critical range
- 2 N/A – 30 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85004
- SNOMED
- 900000000000003002
- Specimen volume
- 2-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- Hemolysis max
- 300
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Doctors may order this test to diagnose or monitor conditions like infections (bacterial, viral, or fungal), autoimmune diseases, leukemia, or other blood disorders. It can also help assess immune function or response to treatment.
Types of White Blood Cells Measured
The test identifies five main types of white blood cells: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Each type plays a role in fighting different types of infections or responding to inflammation.
Absolute Counts and Percentages
Beyond percentages, the test provides absolute counts (actual numbers) of each cell type per microliter of blood. These numbers help pinpoint imbalances that may signal specific health concerns.
Common Reasons for Testing
Frequently, this test is done when you have symptoms like fever, fatigue, frequent infections, or unexplained weight loss. It’s also part of routine check-ups for people with chronic illnesses or those undergoing cancer treatment.
Reference range
Adult: 4.5-11.0 x 10^9/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal counts can signal infections (e.g., high neutrophils may indicate bacterial infections), immune disorders (e.g., low lymphocytes may suggest HIV or other immune deficiencies), or blood cancers (e.g., elevated blasts in leukemia). Monitoring changes over time helps guide treatment decisions.
Short name
WBC Differential
Frequently asked questions
What does a ‘differential’ mean in this test?
How long does it take to get results?
Can I eat or drink before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy