KFT Test Report Explained: Urea, Creatinine, eGFR and Salts
Read a KFT test report as a pattern, not a list of red and black numbers. Urea, creatinine, eGFR and the salts move together in recognisable ways, and the shape they make (dehydration, big muscles, or a kidney that is genuinely struggling) tells you far more than any single flagged line.
Quick facts
- Also called: RFT (renal function test), kidney profile, KFT panel.
- Usual lines: urea or BUN, creatinine, eGFR, uric acid, sodium, potassium, chloride, sometimes calcium and bicarbonate.
- Fasting: usually not needed for KFT alone; follow the lab if sugar or lipids are on the same sample.
- Most useful number: eGFR, and especially its trend across months.
- Ranges: typical lab ranges vary by lab, so use the range printed on your report.
What does each line on a KFT test report mean?
Picture your kidneys as a pair of very fussy sieves. Blood flows through them all day, waste slips out into the urine, and useful salts are held back in careful amounts. The KFT simply samples the blood to see how well that sieving is going.
- Urea / BUN: waste made when the liver breaks down protein. It rises with poor kidney filtering, but also with thirst, a high-protein meal or bleeding in the gut. Full detail is in our blood urea report guide.
- Creatinine: waste from muscle. More muscle, more creatinine. A steadier marker of filtering than urea.
- eGFR: not measured directly. The lab calculates it from creatinine, age and sex to estimate how many millilitres of blood the kidneys clean each minute.
- Uric acid: waste from purines. Linked with gout and stones; our uric acid and desi food article covers it.
- Sodium, potassium, chloride: the salts that keep fluid, nerves and the heartbeat steady. See the electrolyte report guide for each.
What is eGFR in KFT, and which numbers worry doctors?
eGFR is the headline. As a rough guide, a value around 90 or above usually means normal filtering, 60 to 90 can be normal for an older adult or an early sign worth watching, below 60, especially when repeat tests stay there, may point to kidney disease, and below 15 suggests kidney failure. These bands don’t fit everyone equally. Very muscular people, very thin elderly people, amputees and people with advanced liver disease can all get a misleading eGFR, which is why doctors sometimes add a cystatin C test that ignores muscle.
The creatinine, eGFR and urine ACR trio is explained further in our creatinine and eGFR guide. Here, the point is how the lines lean on each other.
Which patterns show up most often?
| Pattern | What you see | Common story |
|---|---|---|
| Dehydration | Urea up much more than creatinine; sodium high or high-normal | Hot day, fasting, vomiting, loose motions |
| Muscle | Creatinine mildly high, urea normal, eGFR slightly low | Gym-goer, labourer, creatine powder, big meat meal |
| Kidney pattern | Urea and creatinine both up, eGFR down, potassium may climb | Diabetes, high BP, long painkiller use, true kidney disease |
| Gut bleeding | Urea high, creatinine normal | Black stools, ulcer history: needs a doctor |
The lab may also print a BUN to creatinine ratio. A high ratio leans toward dehydration or protein load; a balanced rise in both leans toward the kidney itself. Your doctor reads that ratio, not the internet.
A single red creatinine after a hard workout and a thirsty afternoon is often a hydration story, not a kidney story.
Why might a KFT need repeating?
Because kidneys are sensitive to the day you had. A long Ramzan fast, a summer bus ride without water, a heavy leg day, a diarrhoea bout or a plate of nihari the night before can each nudge urea and creatinine upward for a short while. A borderline report taken on such a day is often normal two weeks later.
Before you repeat a borderline KFT
Spend the day before drinking water normally, skip heavy gym work for 48 hours, avoid a large meat meal that evening, and go in the morning. Then carry last year’s report: a stable eGFR over months reassures far more than one result does, and a steady downward slide is worth acting on even if every line is still black.
- Lay your old and new reports side by side, oldest first.
- Write the eGFR from each on one line with dates. Is it flat, falling slowly, or dropping fast?
- Note what was different on test day: fasting, illness, exercise, new medicines.
- Check potassium. A high potassium with a falling eGFR deserves a doctor’s call soon.
- Take the list to your doctor and ask whether a urine ACR or ultrasound is needed. Don’t stop or change any medicine yourself.
KFT and LFT: what’s the difference?
KFT checks the kidneys’ filtering and salts. LFT checks the liver: enzymes like ALT and AST, bilirubin and proteins such as albumin. They’re often ordered together because many medicines are handled by one organ or both, and because a low albumin from liver disease can change how kidney numbers read.
Get same-day care if a report shows a very high potassium or a sudden large jump in creatinine, or if anyone with an abnormal KFT has little or no urine for 12 hours, swollen legs and face with breathlessness, confusion, a racing or irregular heartbeat, or vomiting that won’t stop. People with diabetes, high BP or known kidney disease should have every abnormal KFT reviewed rather than repeated on their own. Never cut fluids, salt or medicines to “fix” a number without medical advice; kidney patients also need a doctor’s go-ahead before high-protein or high-potassium diets.
KFT report questions people search
What does a KFT test mean?
KFT means kidney function test, a blood panel that checks how well the kidneys clear waste and balance salts. It usually includes urea, creatinine, eGFR, uric acid and electrolytes.
What is the normal range for KFT?
Each line has its own range, and those vary by lab and machine. Use the reference column printed beside each result on your report rather than a chart from elsewhere.
Is fasting required for a KFT test?
Usually not for the kidney panel alone. If sugar or cholesterol are being tested on the same sample, the lab may ask for an overnight fast, and some advise skipping a heavy meat meal the evening before.
What is eGFR in KFT?
It is an estimate of how much blood the kidneys filter each minute, calculated from creatinine, age and sex. It is the single most useful line for tracking kidney health over time.
Is RFT the same as KFT?
Yes. Renal function test and kidney function test are two names for the same panel, though different labs include slightly different lines.
What is the difference between KFT and LFT?
KFT looks at kidney filtering and salts; LFT looks at liver enzymes, bilirubin and proteins. They answer different questions and are often ordered together.
Can dehydration raise creatinine and urea?
Yes. Being short of water raises urea sharply and creatinine a little, and the numbers often settle after normal drinking for a few days.
Does gym work or protein powder affect KFT?
It can. Heavy training and muscle bulk raise creatinine, and creatine powders can push it up further, which may lower the calculated eGFR without any kidney problem. Tell your doctor what you take.
How much is a kidney function test in Pakistan?
It varies widely by city, lab chain and how many lines are included. Ask the lab for the price of the exact panel your doctor wrote, since some packages add urine tests.
How often should a diabetic get a KFT?
Your doctor sets the schedule, commonly at least once a year with a urine ACR, and more often if the eGFR is falling or medicines are changed.
Browse more panels in Lab Reports Decoded.