Kidney function test (RFT): creatinine, urea and eGFR explained
What a kidney function test (RFT) shows, normal creatinine and urea levels, what eGFR means, who should be tested in Pakistan, and how to protect your kidneys.
3 min readUpdated 31 October 2026
This is general information only, not medical advice. Please always confirm with your medical consultant or a certified doctor before using any medicine, test or treatment.
Kidney disease often has no symptoms until it is advanced. In Pakistan, diabetes, high blood pressure, kidney stones and overuse of painkillers are the main causes. A simple blood test, the kidney function test (RFT or KFT), can find a problem early, when it is easier to slow down.
Compare prices for the RFT, serum creatinine or blood urea.
What an RFT includes
- Serum creatinine: a waste product from muscles that healthy kidneys remove. When kidneys work less well, creatinine goes up.
- Blood urea (or BUN): another waste product; it also rises with dehydration, a high-protein diet or bleeding in the gut.
- Electrolytes: sodium, potassium and chloride. High potassium can be dangerous for the heart.
- Often uric acid and calcium.
Typical adult ranges
Use the range on your own report. Typical values:
| Test | Typical adult range |
|---|---|
| Serum creatinine | about 0.6 to 1.2 mg/dL (a little higher in muscular men) |
| Blood urea | about 15 to 45 mg/dL |
| Potassium | about 3.5 to 5.0 mmol/L |
What eGFR means
Many reports now show the eGFR (estimated glomerular filtration rate), calculated from creatinine, age and sex. It is the best single guide to kidney function:
| eGFR (mL/min/1.73 m²) | Usual meaning |
|---|---|
| 90 or above | Normal (if no other sign of kidney damage) |
| 60 to 89 | Mildly reduced |
| 30 to 59 | Moderately reduced |
| 15 to 29 | Severely reduced |
| Below 15 | Kidney failure |
An eGFR below 60 for more than three months means chronic kidney disease (CKD). One low result during an illness or dehydration can be temporary; your doctor will repeat it.
Who should be tested
- Everyone with diabetes or high blood pressure, at least once a year, together with a urine ACR test.
- People with kidney stones, swelling of the feet or face, foamy urine or blood in the urine.
- People who take painkillers often, or have a family history of kidney disease.
- Before and during some medicines and before contrast scans.
Protecting your kidneys
- Keep blood pressure and sugar under control. Read about HbA1c.
- Avoid regular use of painkillers such as ibuprofen and diclofenac without a doctor's advice; they can harm the kidneys. Paracetamol in the correct dose is usually safer for occasional pain.
- Drink enough water, especially in the heat; dehydration and heat stroke can injure the kidneys.
- Reduce salt; avoid unknown herbal remedies and "kushtay".
- Do not stop blood pressure medicines such as losartan or amlodipine on your own.
See a doctor quickly if
- You pass very little urine, have swelling with breathlessness, or feel confused or very weak.
- Severe side or back pain with fever or vomiting (possible stone with infection).
In an emergency call 1122 or see the emergency page. Find labs in Lahore, Karachi or Islamabad, and read about the urine R/E test.
This is general information only, not medical advice. Please always confirm with your medical consultant or a certified doctor before using any medicine, test or treatment.