Lymphocyte Count in Blood (Absolute Count)
This test measures the number of lymphocytes, a type of white blood cell that helps your immune system fight infections and diseases.
["Lymphocytes are key to your body’s defense; abnormal counts may signal immune issues or other health concerns."]
Key facts at a glance
- LOINC
- 107062-2
- Short code
- BMCD3T
- Synonyms
- Cells.CD3+CD19- (T cells)/lymph NFr Mar FC
- Category
- chemistry
- Sample
- serum
- Container
- Heparinized (sodium or lithium heparin) sterile tube for bone marrow aspirate; EDTA tube acceptable for some flow cytometry platforms; transfer to flow cytometry lab in sterile condition
- Units
- N/A
- Ref low
- 5
- Ref high
- 20
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- flow-cytometry
- CPT
- 86355
- SNOMED
- 40970007
- Specimen volume
- 1-3 mL of bone marrow aspirate in anticoagulant tube; minimum 0.5 mL acceptable for pediatric samples
- Stability
- Specimen should be processed within 24 hours of collection when stored at room temperature (18-25°C); may be refrigerated at 2-8°C for up to 48 hours if immediate processing is not feasible; viability decreases significantly beyond 48 hours
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–48 hours
- Order
- routine
Why It’s Done
Doctors may order this test to check for infections, autoimmune conditions, or other immune-related problems. It can also help monitor treatments for conditions like leukemia or HIV.
What to Expect
A simple blood draw is used. You’ll lie down while a healthcare provider inserts a needle into your arm. The blood is then sent to a lab for analysis.
Normal vs. Abnormal Results
While reference ranges vary by lab, lower-than-normal counts may indicate immune suppression, while higher-than-normal counts could suggest chronic infections or certain cancers.
Common Conditions
Lymphocyte counts are often checked in people with weakened immune systems, those recovering from illness, or those undergoing cancer treatment.
Reference range
Reference ranges for bone marrow T cell (CD3+CD19-) subsets vary by age. Adult bone marrow typically shows T cells comprising 5-20% of lymphocytes. Pediatric values may differ. Always interpret in conjunction with concurrent bone marrow morphological and immunophenotypic assessment.N/A
No special patient preparation required. Recent transfusion, immunosuppressive therapy, or chemotherapy may affect results and should be documented. Bone marrow aspiration procedure requires standard informed consent and local anesthesia.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: Lymphocytes play a critical role in immune response. Low counts may reflect conditions like HIV/AIDS, certain cancers, or severe infections, while elevated counts can signal chronic inflammation, autoimmune disorders, or reactive immune responses.
Short name
Lymphocyte Count
Frequently asked questions
What causes a low lymphocyte count?
What causes a 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