Monocyte count in peripheral blood
This test measures the number of monocytes, a type of white blood cell that helps fight infection and inflammation in your body.
["Monocytes help protect your body by responding to infections and tissue damage."]
Key facts at a glance
- LOINC
- 71648-0
- Short code
- Monocytes NFr.DF Fld Manual
- Synonyms
- Monocytes NFr.DF Fld Manual
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- manual-count
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Might You Need This Test?
Your doctor may order this test to check for infections, inflammatory conditions, or other health issues that could affect your white blood cell counts. It can also help monitor certain treatments or conditions like leukemia or autoimmune diseases.
What Does a Result Mean?
Results are typically reported as the number of monocytes per microliter (µL) of blood. High or low counts may signal different health concerns, so your doctor will interpret the results in the context of your overall health and symptoms.
Sample Collection and Preparation
A small blood sample is drawn from a vein, usually in your arm. The sample is sent to a lab for analysis. Monocytes are counted using a blood cell counter or automated analyzer.
Common Reasons for Testing
Tests for infections (such as tuberculosis or chronic infections), inflammatory diseases (like rheumatoid arthritis), or to evaluate the effectiveness of treatments targeting white blood cells.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Changes in monocyte levels can indicate underlying health issues, such as infections, immune system disorders, or certain cancers. High levels may suggest chronic inflammation or infections, while low levels might point to immune deficiencies or certain blood disorders.
Short name
Monocyte count
Frequently asked questions
What causes my monocyte count to be different from what’s expected?
Is there anything I should do to prepare for this test?
Can high or low monocyte counts be dangerous?
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