Liver & KidneysNo Fasting RequiredTurnaround: 4–8 hours (same day)

Kidney Function Test (KFT / RFT / Renal Panel)

Also known as: Renal Function Test, RFT, Renal Panel, Kidney Profile, Basic Metabolic Panel (BMP)

Parameters Measured in the Report

A breakdown of individual biomarkers and biological reference intervals typically found in your report:

Biomarker	Standard Range	Unit	What It Means
Serum Creatinine (Creatinine)	Men: 0.7–1.3 Women: 0.6–1.1	mg/dL	Metabolic waste product of muscle creatine breakdown; key indicator of filtration capacity.
Estimated GFR (eGFR) (eGFR)	Normal: ≥ 90 Mild Decrease: 60–89 Moderate CKD: 30–59 Severe: < 30	mL/min/1.73m²	Calculated mathematical estimate of actual blood volume filtered by the kidneys per minute.
Blood Urea Nitrogen (BUN) (BUN (or Blood Urea: 15–45 mg/dL))	7–20	mg/dL	Waste nitrogen formed in the liver from dietary protein digestion and cleared by kidneys.
BUN / Creatinine Ratio (BUN/Cr Ratio)	10:1 to 20:1	ratio	Helps differentiate dehydration (prerenal azotemia) from intrinsic kidney damage.
Serum Uric Acid (Uric Acid)	Men: 3.5–7.2 Women: 2.6–6.0	mg/dL	End product of purine metabolism; elevated in gout, kidney stone formation, and reduced excretion.

* Note: Reference ranges may vary slightly between testing instruments and reagent kits. Always refer to the reference interval printed on your specific pathology report.

Clinical Focus

Serum Creatinine, Blood Urea Nitrogen (BUN), eGFR (filtration rate), Uric Acid, and Electrolytes.

Sample & Specimen

Venous blood (Serum tube)

Fasting Protocol

Fasting is not strictly required, but avoid eating large quantities of red meat before the test.

Turnaround Time

4–8 hours (same day)

What Is This Test?

The Kidney Function Test (KFT / RFT) is an essential diagnostic panel evaluating how effectively your kidneys are filtering metabolic waste products from the blood into urine. Each day, healthy kidneys filter approximately 180 liters of blood through millions of microscopic capillary units called nephrons. When kidney function declines, waste compounds like creatinine (a byproduct of normal muscle breakdown) and urea (a byproduct of protein metabolism) begin accumulating in the bloodstream. Because kidney disease is frequently silent in its early stages, KFT screening is crucial for early detection before symptoms appear.

Why Did Your Doctor Order This Test?

Physicians routinely prescribe the KFT / RFT in the following clinical scenarios:

Routine annual screening in individuals with high blood pressure, diabetes, or cardiovascular disease

Investigating symptoms: facial puffiness, swelling around ankles/feet (edema), foamy urine, or changes in urination frequency

Assessing kidney function before administering intravenous iodinated contrast dye for CT scans or angiographies

Monitoring patients taking medications cleared by the kidneys (NSAIDs, ACE inhibitors, aminoglycosides, lithium)

How to Prepare Before Your Test

Fasting Requirement: Fasting is not strictly required, but avoid eating large quantities of red meat before the test.

Stay normally hydrated with plain water. Dehydration can falsely elevate urea and creatinine readings.
Avoid unusually heavy consumption of cooked red meat for 24 hours prior, as it can temporarily increase serum creatinine.
Avoid strenuous, muscle-damaging workouts (e.g., heavy powerlifting or marathon training) the day before testing.

Understanding Your Results

What higher or lower readings generally mean in clinical practice:

If Values Are Higher Than Normal

Elevated Serum Creatinine accompanied by low eGFR (<60 mL/min/1.73m²) indicates impaired kidney filtration, seen in chronic kidney disease (CKD), uncontrolled hypertension, diabetic nephropathy, or acute dehydration. High Uric Acid (>7.2 mg/dL) can precipitate painful crystal deposits in joints (gout) or kidney stones.

If Values Are Lower Than Normal

Low serum creatinine is typically non-pathological and reflects lower muscle mass, aging, or a vegetarian diet with low dietary creatine intake. Low BUN can occur in malnutrition, severe liver disease, or overhydration.

Frequently Asked Questions

What is eGFR, and why is it more informative than creatinine alone?

Creatinine production depends on body muscle mass (a muscular athlete naturally produces more than a frail elder). eGFR standardizes creatinine against your age, sex, and body surface area to give a standardized percentage of functioning kidney filtration.

Related Laboratory Tests

Tests frequently prescribed together or used as follow-up investigations:

Urine Routine & Microscopic Examination (Urine R/M)

Physical properties (color, clarity, specific gravity), chemical dipstick (protein, glucose, nitrites), and microscopic sediment.

Urine Microalbumin / Albumin-to-Creatinine Ratio (UACR)

Microscopic leakage of albumin protein standardized against urine creatinine excretion.

Serum Electrolytes (Sodium, Potassium, Chloride, Bicarbonate)

Electrically charged mineral ions: Sodium (Na+), Potassium (K+), Chloride (Cl-), and Bicarbonate (HCO3-).

Liver Function Test (LFT / Hepatic Panel)

Bilirubin fractions, transaminases (ALT/SGPT, AST/SGOT), Alkaline Phosphatase (ALP), and proteins (Albumin, Globulin).

Medical & Diagnostic Disclaimer

This guide is published for educational and patient informational purposes only. It is not a substitute for professional medical evaluation, diagnosis, or clinical advice.

A laboratory result that falls slightly outside standard statistical reference intervals does not automatically indicate disease; conversely, a normal result does not guarantee the absence of medical conditions. Only your attending physician can interpret lab findings in the context of your medical history, physical exam, and symptoms.