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Private Kidney Function Test
Kidney function testing including eGFR and electrolytes, explained by a doctor.
Kidney function rarely announces itself. eGFR and electrolytes together give a picture of how well the kidneys are filtering, and a single result out of range often means less than a trend does. We explain what yours means for you.
- Ten clinics across the UK
- Same-day Appointment
- In clinic, by phone or video
- GMC-registered doctors
- CQC registered
- Quick & Accurate Results
Book your KIDNEY FUNCTION TEST
Chronic kidney disease is common, largely silent, and substantially under diagnosed. Most people with early kidney impairment have no symptoms at all, and by the time symptoms appear a great deal of function has usually been lost. The great majority of cases never progress to anything serious, provided they are found and the underlying causes are managed, which makes this one of the more genuinely worthwhile things to test.
The blood test measures creatinine and calculates eGFR, an estimate of how well your kidneys are filtering. A urine test for protein is equally important and often skipped, because protein in the urine is both an early sign of kidney damage and one of the strongest predictors of whether it will progress. Testing blood alone gives you half the picture.
Results in 24 to 48 hours with a GP report explaining what the numbers mean, which matters here because eGFR is widely misunderstood and a single slightly low reading causes a lot of unnecessary alarm.
Why patients choose our KIDNEY FUNCTION TEST SERVICE
- Results in 24 to 48 hours.
- eGFR explained in the context of your age and circumstances rather than against a bare threshold.
- Urine protein testing available alongside, which is where a lot of the real information is.
- Blood pressure and diabetes assessed, since they cause most chronic kidney disease.
- Medication reviewed, since several common drugs affect kidney function.
- Repeat testing, which is essential because a single result cannot diagnose chronic disease.
- Nephrology referral arranged where warranted.
- No referral, no eligibility criteria, no waiting list.
- Results shared with your NHS GP on request, with your consent.
SAME DAY KIDNEY FUNCTION TEST APPOINTMENTS
Preparation
No fasting needed. Avoid heavy protein intake and strenuous exercise for 24 to 48 hours beforehand, since both raise creatinine and can make kidney function look worse than it is. This catches out gym goers and anyone on a high protein diet routinely. Stay normally hydrated: dehydration also raises creatinine.
Evening and Weekend Appointments
Monday to Friday, 8am to 7pm, Saturday 9:00 am to 2:00pm
How to book your Kidney Function Test
Step 1
Book Your Test
Same day usually. No fasting, but avoid heavy protein and hard exercise for a day or two beforehand.
Step 2
Samples
A blood sample, plus a urine sample where you are having protein testing.
Step 3
Results in 24 to 48 Hours
Returned with a GP report interpreting them against your symptoms.
Step 4
Interpretation and Next Steps
A GP explains what the numbers mean, arranges a repeat test where needed, and refers on if warranted.
Why choose Private Medical Clinic for KIDNEY FUNCTION TEST
- CQC registered provider, with documented clinical governance.
- Results in 24 to 48 hours.
- eGFR interpreted properly rather than compared to a single threshold.
- Blood pressure and diabetes assessed at the same time, since they cause most kidney disease.
- Medication reviewed for drugs that affect the kidneys.
- Repeat testing built into the approach, since one reading proves nothing.
- Nephrology referral where warranted.
- Ten clinics across the UK.
- Results shared with your NHS GP on request.
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Private KIDNEY FUNCTION TEST Across The UK
- Private Blood Tests in Birmingham
- Private Blood Tests in Sutton Coldfield
- Private Blood Tests in London
- Private Blood Tests in Newcastle
- Private Blood Tests in Leicester
- Private Blood Tests in Bournemouth
- Private Blood Tests in Oxford
- Private Blood Tests in Derby
- Private Blood Tests in Cambridge
- Private Blood Tests in Manchester
Ongoing care with a Membership Plan
Relevant for anyone with ongoing allergic disease needing repeat prescriptions and seasonal review. The Family plan suits households with a child with allergies. Twelve month minimum commitment, auto renews unless cancelled.
Individual Plan
£79
Per User/month, billed annually
Affordable Healthcare For Individuals
- Full plan for 1 person
- 10 free yearly consultations
- Complete health screen annually
- 50% off on our Super Screen bloods
- Priority access to appointments
- Free prescriptions & letters/referrals
- Exclusive, direct access to a clinician
Couples Plan
Popular£149
Per User/month, billed annually
Full Benefits For Two People
- Includes single plan benefits
- Covers 2 people
- 10 free yearly consultations for you and your partner
- 2x Super Screen Health Check P.A.
Family Plan
£199
Per User/month, billed annually
Cover The Whole Family For One Fixed Price
- Up to 2 adults and 2 children
- £25 per additional child
- 10 free yearly consultations for all members
- 4x Super Screen Health Check P.A.
- Includes all single plan benefits
Who should TEST
- You have high blood pressure or diabetes. Together these cause the majority of chronic kidney disease in the UK.
- You take medication affecting the kidneys: long term NSAIDs such as ibuprofen, ACE inhibitors, diuretics, lithium, some antibiotics.
- You take NSAIDs regularly for pain. Worth singling out, because long term over the counter ibuprofen is a genuinely common and avoidable cause of kidney impairment and most people have no idea.
- You have a family history of kidney disease, including polycystic kidney disease.
- You are of South Asian or Black African or Caribbean background, where risk is higher.
- You have had recurrent urinary or kidney infections, or kidney stones.
- You have gout, which is associated with kidney disease.
- You have heart failure or cardiovascular disease.
- You are over 60.
- You use protein supplements heavily, or use anabolic steroids
Understanding EGFR AND YOUR RESULTS
Creatinine is a waste product from muscle, cleared by the kidneys. As filtering declines, creatinine rises. eGFR, estimated glomerular filtration rate, converts creatinine into an estimate of filtering capacity, adjusted for age and sex, expressed in ml/min/1.73m².
How it is staged, broadly: 90 or above is normal; 60 to 89 is mildly reduced, which in an older person with no protein in the urine is often simply age related; 30 to 59 indicates moderate reduction; below 30 indicates severe reduction and warrants specialist input.
Three things that cause unnecessary alarm, and are worth understanding before you test:
- eGFR falls naturally with age. A reading of 70 in someone in their seventies is usually normal ageing rather than disease.
- A single reading cannot diagnose chronic kidney disease. The definition requires abnormality persisting for at least three months, which is why repeat testing matters. Dehydration, a recent high protein meal, hard exercise, or a short course of ibuprofen can all lower a one off eGFR.
- eGFR is an estimate, and it is less accurate at the extremes of muscle mass. Very muscular people can have a low eGFR with entirely healthy kidneys, and people with very low muscle mass can have a falsely reassuring one.
Why urine protein matters as much as the blood test. Albumin in the urine, measured as ACR, is one of the earliest signs of kidney damage and a strong predictor of progression. UK guidance stages kidney disease using eGFR and ACR together, and someone with a mildly reduced eGFR and no protein in the urine has a very different outlook from someone with the same eGFR and significant protein. A kidney assessment without a urine test is incomplete, and that is worth knowing before you buy one.
On what actually helps. Most chronic kidney disease progresses slowly or not at all when the causes are managed: blood pressure control, diabetes control, avoiding regular NSAIDs, stopping smoking, and treating cardiovascular risk. Specific medications, including ACE inhibitors and SGLT2 inhibitors, protect kidney function in the right patients. Only a small proportion of people with reduced eGFR ever need dialysis, and saying so plainly is more useful than leaving someone to search it themselves.
PRIVATE VS NHS KIDNEY FUNCTION TEST
| Private | NHS | |
|---|---|---|
| Referral | None | Via GP, on clinical indication |
| Waiting time | Same Day | Practice availability |
| Results | 24 to 48 hours | Several days to two weeks |
| Interpretation | GP report and consultation | Discussed at a follow up |
| Urine ACR | Ask at your appointment | Standard part of NHS assessment |
| Monitoring for diagnosed CKD | Available | Free, structured, with an annual review |
| Nephrology referral | Arranged | Within the NHS pathway |
| Cost | £95 | Free |
If you are diagnosed with chronic kidney disease, NHS care is the right place for long term monitoring, because it includes structured annual review, medication management and specialist referral pathways. Private testing is worth paying for to get an answer quickly.
KIDNEY FUNCTION TEST FAQS
No, but avoid heavy protein and strenuous exercise for a day or two beforehand, and stay normally hydrated.
90 or above. 60 to 89 is mildly reduced and often normal for age, particularly with no protein in the urine.
Yes, ideally. Urine protein is one of the earliest signs of damage and one of the strongest predictors of progression. A blood test alone is an incomplete assessment.
Acute causes often improve when the cause is removed. Established chronic damage generally does not reverse, but progression can usually be slowed substantially or halted.
Depends on the result and your risk factors. Anything abnormal needs repeating within three months.
An estimate of how well your kidneys are filtering, calculated from creatinine and adjusted for age and sex.
Usually not immediately. eGFR falls with age, a single reading can be affected by dehydration, exercise, protein intake and medication, and chronic kidney disease requires abnormality persisting over three months.
Regular long-term use can and it is a common and avoidable cause. Occasional use for a few days is a different matter. Worth reviewing if you take it routinely.
Heavy use raises creatinine and can make eGFR look worse than it is. Whether it causes actual harm in healthy kidneys is debated; in existing kidney disease it warrants caution.
With your consent, we would encourage it for anything abnormal.
Ready to book your KIDNEY FUNCTION TEST?
Book a same-day test. Results in 24 to 48 hours with a GP report that explains what your eGFR means rather than leaving you to guess.