Skip to content

Serum or plasma probe for vitamin D binding protein (DBP) concentration

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of vitamin D binding protein (DBP) in your blood. DBP helps transport vitamin D in your body, and its levels can be influenced by factors like kidney function and certain medications.

Quick summary

["Understanding your DBP levels can help assess how well your body handles vitamin D."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
32021-8
Short code
HTLV I DNA Ser Ql NAA+probe
Synonyms
HTLV I DNA Ser Ql NAA+probe
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Might Be Ordered

Your healthcare provider may recommend this test if they suspect conditions affecting vitamin D metabolism, kidney function, or if you have symptoms like fatigue, bone pain, or frequent infections. It may also be part of a broader evaluation for conditions like hypoparathyroidism or certain genetic disorders.

What to Expect Before the Test

No special preparation is usually needed. You may provide a blood sample drawn from a vein in your arm. If you’re taking medications that affect kidney function, let your provider know before the test.

What the Results Mean

While DBP levels alone don’t directly indicate vitamin D status, they can be part of a broader assessment. High levels might suggest kidney disease or certain genetic conditions, while low levels could be linked to kidney dysfunction or other metabolic issues.

Common Causes of Abnormal Results

Changes in DBP levels can occur due to kidney disease, liver disease, pregnancy, or certain medications. Genetic factors may also play a role in naturally high or low levels of DBP.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Vitamin D Binding Protein Level

Frequently asked questions

What does my DBP level tell me about my health?
Your DBP level alone doesn’t diagnose a specific condition but may help identify potential underlying issues affecting vitamin D metabolism or kidney function. It’s often used alongside other tests, like vitamin D levels, to provide a clearer picture of your health.
Do I need to do anything special if my DBP level is abnormal?
If your results are outside the expected range, your healthcare provider will discuss next steps with you. This may include additional tests, lifestyle changes, or monitoring for conditions like kidney disease or genetic disorders.
Can diet or supplements affect my DBP test results?
Dietary factors like vitamin D intake or certain medications (e.g., steroids) may influence DBP levels, but they don’t directly affect the test itself. Always follow your provider’s guidance on timing and preparation.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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