Eosinophil count in serum/plasma (qualitative or semi-quantitative)
This test helps assess the presence of eosinophils, a type of white blood cell, in your blood. Eosinophils are involved in allergic reactions and certain infections.
["Eosinophils may rise in allergic conditions, parasitic infections, or other immune responses."]
Key facts at a glance
- LOINC
- 22285-1
- Short code
- E histolyt Ab Ser Ql
- Synonyms
- E histolyt Ab Ser Ql
- 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
When might this test be needed?
Your doctor may order this test if you have symptoms like persistent itching, skin rashes, asthma, or unexplained allergies. It could also be used to monitor conditions like eosinophilic esophagitis, certain infections, or reactions to medications.
What does an abnormal result mean?
A higher-than-normal eosinophil count may indicate allergies, parasitic infections, certain autoimmune diseases, or reactions to drugs. A lower-than-normal count might suggest immune suppression or other underlying health issues.
How is this test performed?
A blood sample is drawn from a vein, typically in your arm. The sample is then analyzed in a lab to detect and count eosinophils. The test may be qualitative (yes/no) or semi-quantitative (approximate levels).
What can affect this test?
Recent infections, allergies, certain medications (like steroids), or stress can temporarily change eosinophil levels. Avoiding recent infections or allergens for a few days before testing may help get more accurate results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Eosinophils play a key role in fighting parasites and responding to allergies. Elevated levels often point to allergic conditions, parasitic infections, or other inflammatory processes. Monitoring eosinophil counts can help guide treatment for conditions like asthma, eosinophilic gastrointestinal diseases, or certain drug reactions.
Short name
Eosinophil qualitative screening
Frequently asked questions
Why would my doctor order this test?
What are the typical reference ranges?
Is this test painful?
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