Eosinophil count (absolute) in serum/plasma by automated cell counting
This test measures the number of eosinophils, a type of white blood cell, in your blood. Eosinophils help fight infections and respond to allergies and inflammation.
["Eosinophil counts help diagnose and monitor conditions like allergies, asthma, parasitic infections, and certain cancers."]
Key facts at a glance
- LOINC
- 22266-1
- Short code
- ECV1 Ab Titr Ser
- Synonyms
- ECV1 Ab Titr Ser
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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 This Test Might Be Ordered
Your doctor may order this test if you have symptoms like persistent itching, skin rashes, wheezing, unexplained weight loss, or if they suspect an allergic reaction, parasitic infection, or other conditions affecting eosinophil levels.
What to Expect Before the Test
No special preparation is needed. You’ll have a small needle inserted into your arm to draw blood. The process usually takes a few minutes.
What the Results Mean
Results are reported as the absolute number of eosinophils per microliter (µL) of blood. Elevated levels may indicate allergies, infections, or inflammatory conditions, while very low levels might suggest immune system issues.
Common Conditions Linked to Eosinophil Levels
High eosinophil counts can be linked to allergies, asthma, parasitic infections, certain cancers (like lymphoma), and autoimmune diseases. Low levels may be seen in conditions like severe infections or certain immune deficiencies.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Eosinophils play a key role in defending against parasites and mediating allergic reactions. Their elevated presence often signals ongoing immune activity, guiding treatment for conditions like asthma, eosinophilic esophagitis, or parasitic infections.
Short name
Absolute Eosinophil Count (Serum/Plasma)
Frequently asked questions
What causes eosinophil levels to rise?
What does it mean if my eosinophil count is low?
Can diet or lifestyle affect eosinophil counts?
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