A Glomerular Filtration Rate, or GFR, test measures the Kidneys' efficiency in filtering waste using your blood sample. Your Kidneys are two organs on either side of your Spine near your Waist. They have microscopic filters known as glomeruli. These filters remove waste and surplus water from your blood and get rid of them through Urine (Pee). Your Kidneys can't filter your blood as quickly as they should if Kidney disease has caused damage to these small filters. A GFR test measures the volume of blood your Kidneys filter in a minute to screen for Kidney disease. Doctors generally estimate GFR based on the amount of certain waste substances in your blood which is called estimated GFR or an eGFR.
To determine your eGFR, your doctor makes use of the results of Creatinine Test, where creatinine is a waste product generated by normal muscle activity. If your Kidneys aren’t functioning accurately, Creatinine can accumulate in your blood. Your doctor will also take into account other body details, such as your age, weight, height, and sex, since creatinine levels vary depending on factors including body size, diet type, and physical activity levels. After that, this information is put into a GFR calculator, which uses a mathematical formula to determine your eGFR and evaluate renal function.