Basophils and Mast Cells — Cell Count
A laboratory count of basophils and mast cells, related immune cells that can be reported as a number or fraction in the tested specimen.
["This test measures the amount of basophils and mast cells and may help evaluate allergic or inflammatory conditions."]
Key facts at a glance
- LOINC
- 69916-5
- Short code
- Basophils/Masts NFr Snv
- Synonyms
- Basophils/Masts NFr Snv
- Category
- liver
- Sample
- fluid
- Container
- Sterile tube
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 2-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- Hemolysis max
- 300
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test counts basophils and mast cells, which are related white blood cells involved in immune and inflammatory responses. Depending on the specimen and laboratory method, the result may be reported as a number per volume or as a fraction of all counted cells.
Why might I need this test?
This test may be ordered as part of a blood or body-fluid cell count and differential. It can help a clinician evaluate an unexplained increase in white blood cells or investigate symptoms that may be related to allergy, inflammation, infection, or medication effects.
How is the test performed?
A laboratory professional examines the specimen with a counting method and determines the number or proportion of basophils and mast cells. Some laboratory analyzers group these closely related cells together, so the exact reporting method can vary.
How do I prepare for the test?
If the test uses a blood sample, fasting is usually not required unless your clinician gives different instructions. For other specimens, follow the specific collection and preparation directions provided by your healthcare team.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An increased result may occur with allergic conditions, inflammation, infection, certain medications, or other causes of white blood cell activation. A decreased or very low result is often less clinically significant on its own and must be interpreted with the rest of the blood count. The specimen type, symptoms, medications, and laboratory method should all be considered when reviewing the result.
Short name
Basophils/Mast cells
Frequently asked questions
What are basophils and mast cells?
Does this test measure all my white blood cells?
What does an abnormal basophil or mast cell result mean?
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 17, 2026. · Read our editorial policy