Kidney Test

Kidney Function Test (KFT / RFT)

KFT measures waste products in your blood to assess how well your kidneys are filtering. Here's what creatinine, urea and eGFR values mean for you.

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What is a KFT test?

A Kidney Function Test (KFT), also called Renal Function Test (RFT), measures waste products that healthy kidneys should be removing from your blood. When kidneys are damaged or not working well, these waste products build up. KFT is used to diagnose chronic kidney disease (CKD), monitor diabetic or hypertensive kidney damage, and check kidney health before starting certain medications.

KFT Normal Range Chart

TestNormal RangeUnit
Serum Creatinine — Men0.7 – 1.3mg/dL
Serum Creatinine — Women0.5 – 1.1mg/dL
Blood Urea Nitrogen (BUN)7 – 20mg/dL
Serum Urea15 – 45mg/dL
Uric Acid — Men3.5 – 7.2mg/dL
Uric Acid — Women2.6 – 6.0mg/dL
eGFR (kidney filtration rate)Above 90mL/min/1.73m²
Sodium136 – 145mEq/L
Potassium3.5 – 5.1mEq/L
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What does high creatinine mean?

HIGH Creatinine above normal

High creatinine means your kidneys are not filtering waste efficiently. Common causes include dehydration, chronic kidney disease (CKD), diabetes-related kidney damage (diabetic nephropathy), high blood pressure, or certain medications. Mildly raised creatinine with dehydration usually normalises after drinking water. Persistently high creatinine needs investigation.

What does low eGFR mean?

LOW eGFR below 60

eGFR (estimated Glomerular Filtration Rate) shows how much blood your kidneys filter per minute. Below 60 for 3+ months indicates Chronic Kidney Disease (CKD). The lower the eGFR, the more severe the kidney damage: eGFR 30–59 = moderate CKD; eGFR 15–29 = severe; below 15 = kidney failure requiring dialysis or transplant.

What does high uric acid mean?

HIGH Uric Acid above normal

High uric acid (hyperuricaemia) causes gout — painful swollen joints, especially the big toe. It also increases risk of kidney stones. Common triggers in India include high purine foods (red meat, dal in excess, alcohol), dehydration and obesity. Low-purine diet and medication can control it.

Diabetes, BP and kidneys

In India, diabetes and high blood pressure are the two biggest causes of kidney failure. If you have either condition, KFT should be done at least once a year. Early kidney damage (Stage 1–2 CKD) has no symptoms but can be detected by KFT and urine microalbumin test. Catching it early can stop or slow progression.

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Medical Disclaimer: Creatinine levels vary with muscle mass, age and hydration. A single elevated result does not always mean kidney disease. This information is for educational purposes only. Always consult your nephrologist or physician regarding your kidney function test results.