Kidney Function (5) Test

Kidney function or renal function is vital to good health. The pair of kidneys filters the toxins from our blood through urine and helps cleanse the body. It’s recommended to conduct routine kidney function tests to rule out any abnormalities. Blood/urine tests help to monitor any kidney problems. Broadly, kidney function test comprises of many blood/urine tests which monitor various parameters related to the kidney function. The kidney ACR and GFR values are considered to be of great importance. The GFR (Glomerular Filtration Rate) test result determines how well the toxins or waste materials are being filtered by the kidneys. The GFR blood test measures the creatinine level with respect to the person’s age, gender, weight, height and race. The ACR (Albumin to Creatinine Ratio) test result determines the level of albumin or protein in the urine.

For the GFR test, you may be instructed to fast overnight. Eating cooked meat before the test is prohibited, as cooked meat induces increased creatinine level in the blood. It’s recommended to wear sleeveless or short sleeve dress to allow hassle free blood sample collection. For the ACR test, no special preparation is required. It’s important to discuss your health condition and current medication with the doctor. The doctor’s instructions are to be followed sincerely.

If GFR value is below 60, it indicates kidney disease. The GFR number depends on the creatinine level in the blood. A damaged kidney is unable to filter creatinine produced by the muscle tissue well enough from the blood. The creatinine level that is obtained is matched with other parameters like age, gender, weight, height and race to get the correct GFR number. Usually, a low GFR test result is followed by a repeated test to be doubly sure. Continued very low GFR value for 3 months indicate kidney disease.

If ACR value is high or positive, it indicates kidney disease. Presence of albumin or protein in the urine means that the kidney is not filtering the blood well enough. Protein is meant to be present in the blood and not in the urine. Usually, a positive ACR test result is followed by a repeated test to be doubly sure. Continued positive ACR value for 3 months indicate kidney disease.

Venipuncture is used to draw sample blood for GFR testing. Blood sample from the vein is collected in a labelled EDTA vial. Random midstream urine sample is collected in a labelled and sterilized container for laboratory testing.