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Eosinophil count (qualitative manual differential blood smear evaluation)

Published: August 9, 2026Updated: August 16, 2026

This test checks the number of eosinophils, a type of white blood cell, in your blood using a manual microscopic examination. Eosinophils help fight certain infections and respond to allergies.

Quick summary

["Eosinophil counts help diagnose and monitor conditions affecting white blood cells or immune responses."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
14343-8
Short code
Eosinophil NFr Prt Manual
Synonyms
Eosinophil NFr Prt 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
CPT
86592
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 Is Done

Doctors may order this test to investigate symptoms like persistent itching, skin rashes, asthma, or unexplained allergies. It can also help diagnose conditions like parasitic infections, certain cancers, or autoimmune disorders that affect white blood cells.

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 blood sample is then examined under a microscope by a trained lab technician to count eosinophils.

What the Results Mean

Results are reported as qualitative (e.g., high, low, or normal levels of eosinophils) rather than a specific number. High eosinophil counts may suggest allergic reactions, infections, or other immune-related conditions.

Possible Conditions Linked to Eosinophil Counts

Elevated eosinophils can be linked to allergies, asthma, parasitic infections, certain cancers (like lymphoma), or autoimmune diseases. Low eosinophil counts may indicate immune suppression or other blood disorders.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical significance: Eosinophil counts are critical for diagnosing and managing conditions affecting immune responses. High levels often point to allergic reactions, parasitic infections, or inflammatory diseases, while low levels may indicate immune dysfunction or blood disorders requiring further evaluation.

Short name

Eosinophil count (qualitative)

Frequently asked questions

What causes eosinophils to be high?
Elevated eosinophils can result from allergies, asthma, parasitic infections, certain cancers, or autoimmune diseases. Stress, certain medications, or chronic conditions like inflammatory bowel disease may also play a role.
How long does it take to get results?
Results from this qualitative test are typically available within 1 to 2 business days, depending on lab processing times.
Can I eat or drink before this test?
No special diet or fasting is required for this test. You can eat and drink normally before having your blood drawn.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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