Neutrophil-to-Lymphocyte Ratio (NLR) in Whole Blood by Immunoassay
This test measures the ratio of neutrophils to lymphocytes in your blood, which can help assess immune response and inflammation.
["Neutrophils and lymphocytes are key white blood cells; their balance may signal health or disease states."]
Key facts at a glance
- LOINC
- 86236-7
- Short code
- N men sg C synE Ct Spec Qn NAA+probe
- Synonyms
- N men sg C synE Ct Spec Qn NAA+probe
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- 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 Is the Purpose of This Test?
Doctors may order this test to evaluate immune function, inflammation, or response to infections, cancers, or other conditions affecting these cells. It’s often used alongside other blood tests to guide treatment decisions.
How Is the Sample Collected?
A small blood sample is drawn from a vein, usually in your arm. The blood is processed to separate the white blood cells for analysis.
What Does the Result Mean?
A higher ratio may suggest infection, inflammation, or certain cancers, while a lower ratio could indicate immune suppression or other conditions. Your doctor will interpret results in the context of your overall health and symptoms.
Common Reasons for Testing
This test is commonly used in monitoring chronic diseases (e.g., cancer, autoimmune disorders), evaluating infections, or assessing post-surgery recovery. It may also help guide decisions about medications that affect white blood cells.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Neutrophils and lymphocytes play distinct roles in the immune system. Neutrophils are the body’s first responders to infections, while lymphocytes help fight chronic infections and cancers. An elevated ratio may signal acute inflammation or infection, while a suppressed ratio could indicate conditions like leukemia, HIV, or certain immune deficiencies. Doctors use these findings to tailor treatments, such as adjusting chemotherapy or antibiotic therapy.
Short name
NLR (Whole Blood)
Frequently asked questions
Why might my doctor request this test?
What are typical reference ranges?
Can I eat or drink before 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