Lymphocyte count (specimen type unspecified)
This test measures the number of lymphocytes, a type of white blood cell that helps protect your body from infections and diseases.
["Lymphocytes help your immune system fight illness and infection."]
Key facts at a glance
- LOINC
- 105870-0
- Short code
- Lymphocytes # Spec
- Synonyms
- Lymphocytes # Spec
- 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
What Is a Lymphocyte Count?
Lymphocytes are a type of white blood cell that plays a key role in your immune system. They help your body defend against infections, such as viruses and bacteria, and help your body recognize and fight off abnormal cells, like cancer cells. Your doctor may order this test to check your immune system’s health or to monitor conditions that affect lymphocytes, such as infections, autoimmune diseases, or certain cancers.
Why Might You Need This Test?
A doctor may recommend a lymphocyte count test to evaluate symptoms like frequent infections, unexplained weight loss, fatigue, or swollen lymph nodes. It can also be used to monitor conditions like leukemia, lymphoma, HIV, or other immune-related disorders. Sometimes, it’s part of a routine blood test to check overall health.
How Is the Test Performed?
A small amount of blood is drawn from a vein, usually in your arm, using a needle. The blood is then sent to a lab where it is analyzed to count the number of lymphocytes. The results are typically available within a few days.
What Do the Results Mean?
Results can vary depending on your health and medical history. A low lymphocyte count may suggest immune suppression, infections, or certain diseases. A high count might indicate overactive immune responses, infections, or conditions like chronic inflammation. Your doctor will interpret the results in the context of your overall health and symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Lymphocyte counts are crucial for diagnosing and managing immune-related conditions. Low counts can signal weakened immunity, which may require treatment to boost immune function. High counts can point to infections, inflammatory diseases, or other conditions that need further investigation. Doctors use these results to guide treatment plans, such as adjusting medications or starting new therapies.
Short name
Lymphocyte count
Frequently asked questions
What Are Common Causes of Low Lymphocyte Count?
What Are Common Causes of High Lymphocyte Count?
How Often Should I Get 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