Retinol Binding Protein
Private Retinol Binding Protein testing in London for £86, measuring one vitamin A transport marker with results expected in around 3 days.
Turnaround time
3 business days
Biomarkers count
1
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Overview of the Retinol Binding Protein Test
The Retinol Binding Protein blood test measures Retinol Binding Protein, or RBP, the principal transport protein responsible for carrying Vitamin A from the liver through the bloodstream.
The test assesses 1 specialist biochemical biomarker: Retinol Binding Protein.
Retinol Binding Protein is produced primarily by the liver.
After Vitamin A is released from liver stores, Retinol binds to RBP so that it can circulate to tissues throughout the body.
RBP therefore provides information related to Vitamin A transport and nutritional status.
However, the test is not identical to measuring Vitamin A itself.
A direct Retinol measurement determines circulating Vitamin A, while RBP measures the protein responsible for transporting it.
RBP concentrations are influenced by several physiological systems.
Because the protein is synthesised by the liver, severe malnutrition and reduced hepatic protein synthesis can lower circulating RBP.
Renal function also affects RBP.
Circulating RBP is filtered by the kidneys and normally reabsorbed by the proximal tubules.
Reduced kidney clearance can increase serum RBP, while urinary RBP is a different measurement used as a marker of proximal tubular dysfunction.
This distinction is important when interpreting a blood result.
RBP can also respond relatively quickly to changes in nutritional and inflammatory status.
It should not therefore be interpreted as a completely specific Vitamin A deficiency marker.
Direct Vitamin A testing, liver results, renal function and nutritional history can provide important complementary information.
What Does the Retinol Binding Protein Test Check?
The test measures the blood concentration of the principal protein that transports Retinol. This test measures 1 specialist biomarker.
Retinol Binding Protein
Measures the circulating transport protein responsible for carrying Retinol from liver stores to peripheral tissues, supporting nutritional, hepatic and renal assessment.
Who May Benefit From the Retinol Binding Protein Test?
nutritional status requires assessment.
People with suspected Vitamin A deficiency - RBP can provide complementary information about Retinol transport.
People with malnutrition or severe nutritional restriction - Low protein and micronutrient status can reduce RBP.
People with chronic liver disease - The liver produces RBP and impaired synthesis can affect concentrations.
People with kidney dysfunction - Renal clearance influences circulating RBP.
People with malabsorption disorders - Nutritional deficiencies can affect Vitamin A and its transport proteins.
People with a previous abnormal RBP result - Repeat measurement can establish whether the abnormality persists.
People undergoing specialist nutritional assessment - RBP can complement Vitamin A, Albumin and other nutritional markers.
People with an unexplained Vitamin A result - RBP can provide additional context where direct Retinol measurement is difficult to interpret.
How to Prepare
Do not take additional Vitamin A solely to alter the test result.
RBP should be interpreted with nutritional, hepatic and renal context.
Symptoms and Reasons to Consider the Retinol Binding Protein Test
RBP itself does not cause a specific symptom pattern, but abnormalities can occur with nutritional, hepatic or renal disease.
Poor night vision with nutritional risk - Vitamin A deficiency can impair dark adaptation.
Restricted food intake or malnutrition - Nutritional deficiency can lower Retinol and RBP.
Known fat malabsorption - Reduced Vitamin A absorption can affect its transport system.
Chronic liver disease - Impaired hepatic synthesis can reduce RBP.
Known kidney disease - Reduced clearance can alter circulating concentrations.
A previous abnormal Vitamin A result - RBP can provide complementary information.
Retinol Binding Protein is not a standalone test for kidney tubular disease when measured in blood.
Urinary RBP and serum RBP have different clinical interpretations.
Visual symptoms or substantial nutritional deficiency require appropriate clinical assessment.
How to Book Your Retinol Binding Protein Test
The Retinol Binding Protein test can be booked privately for focused nutritional and biochemical assessment.
Choose the Retinol Binding Protein
Select the individual RBP blood test online.
Select your sample collection option
Choose an in-clinic blood draw or professional home or hotel phlebotomy where the specialist processing requirements can be met.
Attend your appointment
A trained healthcare professional collects the required venous blood sample.
Laboratory analysis
Your serum undergoes measurement of Retinol Binding Protein.
Receive your results securely
Your authorised result is delivered securely and can be interpreted alongside Vitamin A, liver and renal markers.
When Will I Receive My Results?
The current London Blood Tests page lists a turnaround of approximately 3 days after laboratory receipt for Retinol Binding Protein.
The specialist laboratory currently lists a 5-day analytical turnaround, so occasional laboratory routing may extend reporting beyond the customer-facing estimate.
Understanding Your Results
A low RBP result can occur with Vitamin A deficiency, severe malnutrition or impaired hepatic protein synthesis.
Inflammation can also lower concentrations.
A result within range suggests circulating RBP is within the laboratory's expected interval.
This does not independently prove optimal Vitamin A stores.
A high serum RBP result can occur with reduced renal clearance.
This should not be confused with urinary RBP, where increased urinary excretion can indicate proximal tubular dysfunction.
Direct Retinol measurement can be useful where the primary clinical question is Vitamin A status.
The laboratory reference range and clinical context should guide interpretation.
Why Book With London Blood Tests?
London Blood Tests provides private RBP testing for nutritional, liver and renal assessment.
Measures Vitamin A transport protein - RBP carries Retinol from the liver to peripheral tissues.
Can complement direct Vitamin A testing - The two measurements provide related but distinct information.
Relevant to nutritional assessment - Malnutrition can lower circulating RBP.
Relevant to liver function - RBP is synthesised primarily by the liver.
Relevant to renal clearance - Kidney function can influence circulating RBP concentration.
Specialist laboratory analysis - The sample undergoes dedicated biochemical testing.
Professional blood collection - Clinic and suitable home or hotel appointments are available.
Clear pricing - The Retinol Binding Protein test costs £86.
Private Retinol Binding Protein Blood Test in London
London Blood Tests provides private Retinol Binding Protein testing for people requiring assessment of Vitamin A transport or related nutritional status.
The test costs £86 and measures 1 specialist biomarker.
The current customer-facing turnaround is approximately 3 days after laboratory receipt.
The result should be interpreted alongside direct Vitamin A, liver and renal markers where appropriate.