CD2-Positive Blasts-to-Total Blasts Ratio, Whole Blood — Flow Cytometry
Measures the proportion of circulating blast cells that carry the CD2 protein, which can help classify certain leukemias or lymphomas.
["This result shows what fraction of blood blasts express CD2 and is interpreted together with other leukemia tests."]
Key facts at a glance
- LOINC
- 13841-2
- Short code
- CD2 Blasts/Blasts NFr Bld
- Synonyms
- CD2 Blasts/Blasts NFr Bld
- Category
- liver
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test measures the proportion of immature blood cells, called blasts, that have the CD2 protein on their surface. CD2 is a cell-surface marker found on many T lymphocytes and on blasts in some types of leukemia or lymphoma.
Why might I need this test?
This test may be ordered when blood counts, symptoms, or other findings suggest a leukemia or lymphoma. It helps characterize blast cells and can provide information about the likely cell lineage or type of blood cancer.
How is the test performed?
A fresh whole-blood sample is analyzed using flow cytometry, which identifies cells and their surface markers. The laboratory reports the proportion of total blasts that are CD2-positive.
How do I prepare for the test?
No special preparation is usually required. Follow any instructions from the laboratory, and tell the healthcare team if you recently had a blood transfusion or received certain chemotherapy or antibody treatments, because these can affect cell testing.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A higher proportion of CD2-positive blasts may be seen in certain T-cell or lymphoid leukemias and lymphomas, but this finding is not diagnostic by itself. A lower proportion may indicate that the blasts do not express CD2 or express it at a level below detection. Results must be interpreted with the blood count, cell appearance, and other flow-cytometry markers.
Short name
CD2 blast ratio
Frequently asked questions
What does a CD2-positive blast mean?
Does this test diagnose leukemia by itself?
Why might my result be difficult to interpret?
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.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy