Eosinophil count in serum/plasma (qualitative or semi-quantitative assay)
This test checks the presence or level of eosinophils, a type of white blood cell involved in allergic reactions and responses to parasites.
["Eosinophils help identify conditions like allergies, asthma, or parasitic infections."]
Key facts at a glance
- LOINC
- 16833-6
- Short code
- E coli K1 Ag Spec Ql IA
- Synonyms
- E coli K1 Ag Spec Ql IA
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- 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
What Are Eosinophils?
Eosinophils are a type of white blood cell that play a role in fighting off certain infections and managing allergic reactions. They release chemicals to attack parasites and reduce inflammation caused by allergens. When your body detects an allergic response or parasitic infection, eosinophil levels may rise to help manage the situation.
When Might This Test Be Ordered?
Your healthcare provider may recommend this test if you have symptoms like persistent itching, skin rashes, asthma, or unexplained weight loss. It could also be used to monitor conditions such as allergic disorders, parasitic infections, or certain types of cancer.
How Is the Test Performed?
A small blood sample is drawn from a vein, usually in your arm. The sample is then analyzed in a lab to detect eosinophils. The test can be qualitative (just identifying presence) or semi-quantitative (estimating levels).
What Do Results Mean?
Results may show normal levels of eosinophils, an elevated count (indicating possible allergies, infections, or other conditions), or a low count (which could signal immune system issues or other health concerns). Exact interpretation depends on your symptoms and medical history.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated eosinophil counts can signal allergic reactions, asthma, parasitic infections, or certain autoimmune conditions. Low levels may suggest immune deficiencies or other systemic issues. This test is often used as part of a broader evaluation for unexplained symptoms or to monitor chronic conditions.
Short name
Eosinophil Screen
Frequently asked questions
Why might my doctor order this test?
What are typical reference ranges?
Can I do anything to prepare for 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