Basic Kidney Function Test (Basic KFT Test)

Basic Kidney Function Test

It is a simple blood test that is used to assess the functional status of kidneys. Humans usually have two kidneys which help to purify the blood and remove waste products from the body in form of urine. Sometimes in the initial stages of kidney dysfunction, there are no symptoms, so to determine kidney impairment, a basic kidney test is required.

Kidneys serve other functions as well such as regulation of water, electrolytes, and acid-base balance in the body. They also secrete certain hormones such as erythropoietin (for red blood cells production), renin (for regulation of blood pressure), and calcitriol (for production of vitamin D).

Why is a Basic Kidney Test prescribed?

Your health care provider may prescribe basic kidney function tests in the following conditions:

• As a part of routine health check-up to assess kidney status especially in pts with diabetes, high blood pressure, heart disease, kidney stones, autoimmune disease, infections, malignancies, etc
• To assess kidney function if there are symptoms like blood in urine, painful urination, swelling of hands and feet
• To monitor severity and progress of kidney disease in a known case of kidney diseas
• To assess the response of treatment of kidney disease
• To assess kidney damage due to nephrotoxic drugs

What are the components of a Basic Kidney Function Test?

It includes measurement of those substances in the blood that are usually excreted in urine since their blood levels increase when there is kidney dysfunction. These include the following:

• Serum Creatinine -creatinine is produced from creatine phosphate in muscles and is excreted in urine
• Blood Urea -it is produced by the breakdown of proteins in the body. High levels may be seen in kidney failure, kidney diseases like glomerulonephritis, pyelonephritis, etc, dehydration, congestive heart failure<
• Serum Uric Acid -it is produced by the breakdown of nucleic acids in the body
• Serum Electrolytes -it includes measurement of sodium, potassium, chloride, bicarbonate levels which are required for functions such as nerve and muscle function, etc
• Blood Sugar Random - constant levels of blood glucose are required for proper body function.

Procedure and prerequisites

The sample for the basic kidney test is taken from blood by inserting a small needle into the vein of your arm. A small amount of blood is then collected in a test tube or vial. You may feel little pain due to needle prick.

Reference range

Serum creatinine	0.5-1.2 mg/dl (females) 0.5-1.4 mg/dl (males)
Blood urea	7-20 mg/dl
Random blood sugar	140 mg/dl/td
Serum uric acid	3.5-7 mg/dl
Serum electrolytes	sodium136-146 mEq/L
Potassium	3.5-4.5 mEq/L
Chloride96	106 mmol/L
Bicarbonate	22-29 mEq/L