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Kidney Function Blood Test

Want to measure your kidney function? Our Kidney Function Blood Test is the test you need.

Kidney function is a core part of your overall health. You can arrange a venous blood draw yourself or visit one of our partner clinics to have your blood taken. You'll get a report with your kidney function test results along with any recomendations of actions to take.

Comes with our

  • Results and doctor's report in 6 days or less
  • Free, next-working day delivery
  • Gold-standard kidney function test

£30.00

Please select a clinic for your blood draw.

Personalise your kidney function blood test

You can choose how you'd like to collect your blood sample. You may also want to add to your test panel depending on your age, sex and any symptoms. You'll save money compared to buying the tests separately.

Choose how to collect your blood sample

Visit a clinic to have your blood taken

£35.00

Visit one of our partner clinics and have a healthcare professional take blood from a vein in your arm. We'll email you with details of how to book your clinic visit after you've placed your order. Over 18s only.

Book a venous draw at home or work with a nurse. You'll receive an email to book your appointment after you've placed your order. Over 18s only.

£70.00

Arrange your own venous blood draw

Free
Add to your test & save

Please select a clinic for your blood draw.

Dr Claire Merrifield

Dr Claire Merrifield

GP, PhD and our Medical Director

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What you need to know about our Kidney Function Blood Test

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Dr Claire Merrifield

Dr Claire Merrifield

GP, PhD and our Medical Director

If you're looking for the most accurate blood test to measure kidney function, this is it.

What does the Kidney Function Blood Test check for and why?

This blood test measure your level of cystatin C. This allows us to caluclate your estimated glomerular filtration rate (eGFR).

When it comes to measuring kidney function, cystatin C has been shown to be more accurate than the commonly used marker creatinine. This is because cystatin C is not affected by muscle mass or supplemental creatine use which can give false creatinine measurements.

What do my kidney function results mean?

Our kidney function blood test will tell you your estiamted glomerular filtration rate or eGFR. This measure takes into account your age and sex and we interpret the results as follows:

eGFR (ml/min/1.73m2) Interpretation
Greater than 90 Normal kidney function
60-89 Stage 2 kidney disease. Mild impairment in kidney function.
30 - 59 Stage 3 kidney disease. Moderate impairment in kidney function. May cause symptoms.
15 - 29 Stage 4 kidney disease. Moderate to severe impairment in kidney function.
Less than 15 Stage 5 kidney disease. Severe impairment in kidney function. Likely to need dianlysis.

What's tested in your Kidney Function Blood Test?

  • Cystatin C

    Cystatin C has been shown to be a more accurate measure of kidney function than traditional creatinine. In particular, cystatin C is not affected by muscle mass or supplemental creatine intake, both of which can cause false results with creatinine.

  • Estimated glomerular filtration rate (eGFR)

    Kidney function is affected by your age and sex. We adjust for this and calculate your estimated glomerular filtration rate (a measure of kidney function).


Kidney function test FAQs