B-cell Lymphocyte Count (Absolute)
This test measures the number of B cells, a type of white blood cell important for immune function, including antibody production.
["Knowing your B-cell count helps assess immune health and response to treatments."]
Key facts at a glance
- LOINC
- 99400-4
- Short code
- CD19CD23
- Synonyms
- CD19+CD23+ Cells NFr Mar
- Category
- chemistry
- Sample
- serum
- Container
- Heparinized bone marrow aspirate collected in sodium heparin or EDTA tube for flow cytometry analysis
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–99 years
- Method
- Flow Cytometry
- CPT
- 88184
- SNOMED
- 395148006
- Specimen volume
- 1-3 mL of bone marrow aspirate
- Stability
- Specimen should be processed within 24-48 hours of collection at room temperature (18-22°C). Do not refrigerate as this may affect cell viability.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why This Test Is Done
Doctors may order this test to evaluate immune system function, diagnose or monitor conditions like chronic lymphocytic leukemia, lymphoma, or autoimmune diseases. It can also help track responses to treatments for cancer or immune disorders.
What to Expect Before the Test
No special preparation is needed. You’ll typically have a small needle inserted into a vein (usually in your arm) to draw blood. The process is quick and usually painless.
What the Test Results Mean
Results are compared to a general reference range for healthy adults. Low counts may indicate immune suppression, infection, or certain cancers, while very high counts could suggest overactive immune responses or conditions like multiple myeloma.
Common Conditions Monitored
This test is often used in patients with suspected or known immune disorders, blood cancers (like lymphoma or leukemia), or those undergoing treatments that affect white blood cells.
Reference range
Reference ranges for CD19+CD23+ cells in bone marrow vary by laboratory and clinical context; results should be interpreted in conjunction with clinical findings and other immunophenotyping data.N/A
No special patient preparation required. Inform the ordering physician of any recent medications, particularly immunosuppressive therapies or recent blood transfusions, as these may affect results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Abnormal B-cell counts can signal underlying immune dysfunction, cancer, or side effects from medications. High levels may indicate chronic infections or overactive immune responses, while low levels could reflect immune deficiency or treatment-related suppression.
Short name
B-Cell Count
Frequently asked questions
What does a low B-cell count mean?
How often should I get this test?
Can diet or supplements affect B-cell counts?
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