Kidney Function Test (KFT / RFT)
What Is This Test?
The Kidney Function Test (KFT), also known as the Renal Function Test (RFT), is a group of blood tests used to evaluate how well your kidneys are functioning. The kidneys filter waste products, maintain fluid and electrolyte balance, regulate blood pressure, and help produce red blood cells.
A KFT panel measures various substances in the blood to assess the kidneys' ability to filter and eliminate waste. It helps detect kidney disease, monitor existing kidney conditions, and evaluate the effects of medications or chronic illnesses such as diabetes and hypertension.
Why this test is performed?
Doctors may recommend the Kidney Function Test to:
- Assess kidney function
- Diagnose acute kidney injury (AKI)
- Detect chronic kidney disease (CKD)
- Monitor kidney disorders
- Evaluate diabetes-related kidney damage
- Assess kidney function in people with high blood pressure
- Investigate swelling or fluid retention
- Monitor patients taking medications that may affect the kidneys
- Evaluate dehydration
- Monitor kidney transplant recipients
Test Preparation
Fasting is usually not required.
Drink adequate water unless your doctor advises fluid restriction.
Inform your healthcare provider about all medications and supplements, especially:
- Diuretics
- Blood pressure medicines
- Painkillers (NSAIDs)
- Creatine supplements
- Antibiotics
Avoid strenuous exercise before the test, as it may temporarily affect creatinine levels.
Medical disclaimer
This article is for general information and education only. It is not medical advice, does not create a doctor–patient relationship, and is not a substitute for consultation with a qualified doctor who has assessed your individual situation. Never delay seeking medical advice because of something you have read here.
In a medical emergency, call 112, or 108 for an ambulance where that service operates, or go to your nearest emergency department. If you are in mental health distress, Tele-MANAS is free and available 24×7 on 14416.
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