Kidney Function Test (KFT)
A focused test for Creatinine, Urea, Uric Acid.
Overview
Measures Creatinine, Urea, Uric Acid. A single-sample test processed at an NABL-accredited lab, with reports in 6 hours and a free doctor review.
The full panel
3 tests across 1 groupEvery parameter, grouped by body system — no clicking to expand.
What this test measures
How well the kidneys are filtering. Creatinine is a waste product of muscle that healthy kidneys clear at a steady rate, so a rise means filtration has fallen; blood urea and BUN reflect protein breakdown and hydration; uric acid comes from purine metabolism. Most labs also report an estimated GFR calculated from creatinine, age and sex, and the panel usually includes the electrolytes sodium, potassium, chloride and calcium.
Kidney disease is silent until a large share of function is already lost, so it is screened for rather than waited for — particularly in diabetes and high blood pressure, which are its two commonest causes. The panel is also ordered before contrast scans, before and during many medications, and for swelling, reduced urine output or unexplained fatigue.
Symptoms that lead to this test
- Swelling of the ankles, feet or around the eyes
- Passing less urine, or urine that is persistently frothy
- Persistent tiredness, nausea or itching
- Known diabetes or high blood pressure, for routine monitoring
- Before a CT scan with contrast, or before starting certain medicines
Understanding your results
Creatinine depends on muscle mass, so the same value can mean different things in a heavily built young man and a frail older woman — the eGFR exists to correct for that, and the trend across reports matters more than any single number. A rise in urea out of proportion to creatinine often reflects dehydration, a high-protein diet or gastrointestinal bleeding rather than kidney damage. Potassium is the value that occasionally needs urgent attention: results outside the reference range, particularly a high potassium, should be discussed with a doctor promptly, and a haemolysed sample is a common false cause that warrants a repeat. Raised uric acid is associated with gout but many people with a high level never develop it.
Indicative only. Reference ranges vary between laboratories and between testing methods, and shift with age, sex and pregnancy — always read your own result against the range printed on your own report, with the doctor who ordered it.
| Parameter | Indicative range | Unit |
|---|---|---|
| Serum creatinine | 0.7–1.3 (men) · 0.6–1.1 (women) | mg/dL |
| Blood urea | 17–43 | mg/dL |
| Blood urea nitrogen (BUN) | 8–20 | mg/dL |
| Uric acid | 3.5–7.2 (men) · 2.6–6.0 (women) | mg/dL |
| Sodium | 136–145 | mmol/L |
| Potassium | 3.5–5.1 | mmol/L |
| eGFR | 90 or above | mL/min/1.73m² |
Why the preparation matters
No fasting is required. Hydration is the real preparation: arriving dehydrated concentrates the blood and lifts urea and creatinine, which is exactly the pattern that causes unnecessary alarm. Avoid a heavy protein or red-meat meal and avoid strenuous exercise for 24 hours beforehand — both raise creatinine independently of kidney function. Creatine supplements should be mentioned, as they raise creatinine directly.
Who should consider this test
- Everyone with diabetes or high blood pressure, at least annually
- Adults over 60, or anyone with a family history of kidney disease
- People on long-term painkillers (NSAIDs) or lithium
- Anyone with recurrent kidney stones or urinary infections
- Before contrast-enhanced imaging
Conditions it helps detect
How home collection works
Patient stories
96% recommend“The phlebotomist arrived exactly on time and was gentle. My report came in five hours with a doctor’s note.”
“Booked at night, sample collected next morning. The parameter breakdown is genuinely thorough.”
“Loved the free doctor review — she walked me through my vitamin D and thyroid results clearly.”