The pair of kidneys is the main filtration system of the body that plays a crucial role in removing waste products from the blood and excreting them via urine. These bean-shaped sets of organs have small filters inside them called glomeruli.  A tiny network of blood vessels, they are nothing but cleaning units of kidneys that clear toxic substances from the blood. Sometimes glomeruli get into trouble and stop flushing out the waste from the body due to various factors or underlying health conditions. When glomeruli are damaged and cannot function as they should, the kidneys also begin to get affected. When the health care practitioner suspects that the kidneys are not functioning properly looking at certain symptoms, a glomerular filtration rate test also called GFR, or EGFR is advised.  A simple blood test that does not require any major preparation indicates the present condition of the kidneys and how much blood is being passed through these filters each minute. This test may also be advised if there are symptoms related to kidney disease.
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Also Read: Acute Kidney Failure: Causes, Symptoms, And Treatment

How Is GFR Calculated?

The health provider uses a method known as a GFR calculator. This is a mathematical formula that estimates the exact rate of filtration per minute. It is done by comparing the results of a blood test that measures creatinine, a waste product filtered by the kidneys. EGFR apart from measuring creatinine can also provide accurate information about the patient’s height, weight, age, and gender which is based on precise mathematical calculations.

Why do I need a GFR test?

GFR may be advised at a later stage as very early-stage kidney disease does not usually show any symptoms. By and large, a GFR test is advised if the patient is at higher risk of getting kidney disease due to certain factors or chronic illnesses such as diabetes, high blood pressure, urinary tract issues, heart disease, or a family history of kidney failure, polycystic kidney disease or when kidneys have started deteriorating.

Symptoms That Indicate Need For GFR

One may need a GFR test if the following symptoms are visible in the body:

  • Unusual urinating
  • Itching
  • Chronic fatigue
  • Swelling in arms, legs, and feet
  • Muscle or abdominal cramps
  • Nausea
  • Loss of appetite
  • Urinary blockage

What Happens During A GFR Test?

Using a small needle, the health care professional takes a blood sample from a vein in the arm to collect a small amount of blood. There is no potential risk of the test other than the slight bruising that goes away in a few hours. The procedure does not take more than five to ten minutes. There is no special preparation other than fasting that is required to be done several hours before the test. The health care provider may ask to stop some medications and give certain instructions that need to be adhered to depending upon the patient’s history and current health condition. He or she should be informed if the person is pregnant as GFR levels will be affected due to pregnancy. While taking blood from some people may be more difficult than from others, apart from that, the test is as simple as a normal blood test.

Also Read: Yoga For Kidney Health: Superb Asanas To Uplift Renal Functions And Detoxify The Body

GFR Results

Though normal value ranges may be slightly different among various laboratories, normally- GFR results may show one of the following:

  • Normal levels that are above 60 ml/min mean you probably don’t have kidney disease
  • Below normal levels that are under 60 ml/min indicate you may have kidney disease
  • Excessively low normal levels or below 15ml/min implies you have kidney failure and will need dialysis or an immediate kidney transplant else it could lead to kidney failure


Abnormal or below 60 levels of GFR require immediate treatment. If the treatment is started immediately, it is possible to prevent complications. The only treatment options for kidney failure are dialysis or a kidney transplant. Although damage to the kidneys is usually permanent, many steps can be taken to prevent kidney damage at the very initial stages. For example, one should control blood sugar if you have diabetes and try to stay in the target blood sugar range since diabetes is one of the common causes of kidney failure. Moreover, bringing in lifestyle changes such as getting more exercise and maintaining a healthy weight, avoiding excessive intake of alcohol and smoking can also lead to a healthier set of kidneys.