CD19/CD38 Immunophenotyping by Flow Cytometry (Blood)
This test measures the presence and proportion of cells expressing CD19 and CD38 markers, often used to identify and characterize certain immune cells, including B-cells and some leukemic cells.
["Helps diagnose and monitor blood disorders like leukemia or lymphoma by checking specific cell markers."]
Key facts at a glance
- LOINC
- 99404-6
- Short code
- CD19CD38
- Synonyms
- CD19+CD38+ Cells NFr Mar
- Category
- chemistry
- Sample
- serum
- Container
- EDTA (purple top) tube for peripheral blood; heparinized tube for bone marrow aspirate to preserve cell viability for flow cytometric analysis
- Units
- N/A
- Ref low
- 2
- Ref high
- 8
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Flow cytometry using fluorescently labeled monoclonal antibodies against CD19 and CD38 surface markers, typically performed on fresh bone marrow aspirate specimens with viability assessment and isotype controls
- CPT
- 86356
- SNOMED
- 365641000124108
- Specimen volume
- 3-5 mL of bone marrow aspirate collected in anticoagulant-containing tube; minimum 1 mL for flow cytometry analysis
- Stability
- Specimens should be processed within 24 hours of collection when stored at room temperature (18-25°C); viability decreases significantly after 48 hours. Refrigeration at 2-8°C may be acceptable for short-term storage but may affect certain surface markers.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
What This Test Measures
CD19 and CD38 are proteins found on the surface of certain immune cells. CD19 is commonly found on B-cells, while CD38 is present on many immune cells, including some B-cells and certain types of leukemia cells. This test quantifies how many cells in your blood sample express these markers, which can help doctors identify abnormal cell populations.
Why It’s Done
Doctors may order this test to diagnose or monitor conditions such as chronic lymphocytic leukemia (CLL), non-Hodgkin lymphoma, or other blood cancers. It can also help track treatment responses or guide decisions about further testing or therapy.
Sample Collection and Preparation
A small amount of blood is drawn from a vein in your arm. The blood is then processed to isolate cells for analysis. This test does not require fasting or special preparation beyond standard blood draw procedures.
What to Expect Before or After
There may be mild discomfort or bruising at the injection site after the blood draw. You can resume normal activities immediately unless your doctor advises otherwise. Results may take several days to weeks, depending on lab processing times.
Reference range
Reference ranges for CD19+CD38+ B-cell subsets in bone marrow vary by age and clinical context. In normal adult bone marrow, CD19+ B cells typically represent 2-8% of total nucleated cells, with CD38 expression varying across maturation stages. Age-specific reference ranges should be established by individual laboratories.N/A
No special preparation required for serum collection. For bone marrow aspiration, patient should follow institutional protocols including informed consent, local anesthesia administration, and monitoring for bleeding or infection post-procedure. Patients on anticoagulants should inform their physician prior to bone marrow collection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
CD19/CD38 Cells
Frequently asked questions
Will this test show if I have a blood cancer like leukemia?
How long will it take to get my results?
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