Lab test · Nephrology
Kidney Function Test (RFT)
Kidney function
- Blood sample
- No fasting
- Report within 24 hours
- Home collection
What this test is for
Kidney function
A kidney function test, also called a renal function test (RFT), is a group of blood tests that show how well your kidneys are filtering waste from the blood. It measures urea and creatinine, which build up when the kidneys are not working well, along with uric acid and electrolytes such as sodium and potassium that the kidneys keep in balance. It helps your doctor find kidney problems early and follow them over time.
Why a doctor may order it
- If you have diabetes or high blood pressure, the two most common causes of kidney disease
- If you have swelling of the legs, face or around the eyes
- If you pass much more or much less urine than usual
- Before and during treatment with medicines that affect the kidneys
- As part of a routine health check-up
How to prepare
Fasting: Not needed.
No fasting is involved. Drink water as you normally would, because being dehydrated can push urea and creatinine up. Keep taking your usual medicines, including blood pressure tablets, unless your doctor has told you otherwise.
At home
- Sample
- Blood sample
- How it works
- The sample collector draws a small amount of blood from a vein in your arm at your home. Every test in the kidney panel is measured from that one sample, and the draw takes only a few minutes.
- Report
- Within 24 hours of collection.
What the results can mean
Your report lists each result next to the laboratory's reference range, and may include an estimated GFR. Raised urea and creatinine suggest the kidneys are filtering less well, which may be short-term, for example from dehydration, or long-term. Abnormal sodium or potassium can also be linked to kidney problems or to medicines. Your doctor will interpret the pattern of results and may suggest urine tests or a scan.
What's included
This test reports 4 measurements:
- Blood urea
- Serum creatinine
- Uric acid
- Serum electrolytes
Related tests
Questions people ask
How is a kidney function test different from serum creatinine alone?
Serum creatinine is a single test. A kidney function test adds urea, uric acid and electrolytes, giving a fuller picture of how the kidneys are coping.
What are the early signs of kidney disease?
Early kidney disease often causes no symptoms at all. That is why people with diabetes or high blood pressure are usually advised to have kidney tests regularly, as their doctor recommends.
Why is potassium important in kidney disease?
The kidneys help remove extra potassium. When they are not working well, potassium can build up, and high levels can affect the heartbeat. Some medicines can also raise potassium.
Do I need a urine test as well?
Often, yes. A urine test for protein, such as a urine albumin-creatinine ratio, can show early kidney damage even when blood tests are normal. Your doctor will advise which tests you need.
How much does a RFT test cost in Dhaka?
With Mukti Health the price is ৳1,440, and the sample is collected at your home in Dhaka. You see the price again before you confirm the booking in the Mukti Health app.
Can I do the RFT test at home in Dhaka?
Yes. Book it in the Mukti Health app and a trained sample collector comes to your home in Dhaka to take the blood sample. You do not need to go to a laboratory.
How long does the RFT report take?
The report is usually ready within 24 hours of the sample being collected.