Red Blood Cell (RBC) Erythrocyte Deformability Index
This test measures how easily your red blood cells can change shape to pass through small blood vessels, which is important for proper circulation and oxygen delivery.
["Assesses RBC flexibility, linked to circulation efficiency and potential vascular health issues."]
Key facts at a glance
- LOINC
- 86285-4
- Short code
- Erythrocyte deformability RBC-Imp
- Synonyms
- Erythrocyte deformability RBC-Imp
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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
Why It’s Done
Doctors may order this test to evaluate conditions affecting red blood cell flexibility, such as hereditary spherocytosis, severe anemia, or microangiopathic hemolytic anemia. It can also help monitor blood flow in patients with vascular diseases or those on certain medications that may affect RBC shape.
How It Works
The test typically involves drawing a small sample of your blood, which is then analyzed using specialized equipment to measure how deformable your red blood cells are under controlled conditions. This helps determine if they can navigate narrow blood vessels effectively.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it involves a specific type of blood sample collection, but this is less common for deformability testing alone.
Possible Results and Interpretation
Results are often expressed as an index or score reflecting RBC flexibility. Lower scores may indicate reduced deformability, which can suggest underlying conditions affecting circulation or red blood cell health.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
RBC Deformability Test
Frequently asked questions
What does a low RBC deformability score mean?
How long does it take to get results?
Can lifestyle changes affect RBC deformability?
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 17, 2026. · Read our editorial policy