eGFR (CKD-EPI) is the abbreviation for estimated glomerular filtration rate, or the amount of blood filtered by the glomeruli per minute. eGFR is a test used to measure kidney function or to determine the stage of existing kidney disease. These measurements are also used to monitor kidney disease and to assess the effectiveness of ongoing treatment.
Chronic kidney disease may be diagnosed when the albumin level is abnormal, even if the eGFR value remains below 60 for three months and is above 60 in cases of kidney damage.
How Is the EGFR Test Performed?
The EGFR test is a rapid diagnostic test used to assess kidney function. However, since EGFR values may vary in children under 18, pregnant women, individuals with high muscle mass, or those with obesity, using this test alone is not appropriate.
It is a simple blood test that can be performed using a specific amount of blood drawn from a vein in the arm. It provides the specialist with important information about kidney function. An abnormal EGFR test result is evaluated by a physician. If chronic kidney disease is suspected, further investigation and different diagnostic tests may be performed to confirm the diagnosis.
What Is the Normal EGFR Value?
EGFR values vary depending on age, gender, and other factors. As a person ages, muscle mass in the body decreases, which causes the rate to drop naturally. For a person in his 20s, the average EGFR is approximately 116 mL/min/1.73 m². For people in their 60s, it drops to 85 mL/min/1.73 m². An EGFR value above 60 indicates that 60 percent of kidney function remains. Generally, the higher the number, the better the kidney function.
Causes of High EGFR
When the urinary tract becomes blocked, the kidneys cannot retain urine and swell; as a result, they cannot function properly and are unable to excrete waste products. In such cases, elevated creatinine levels begin to develop. There are many structures in the kidneys called nephrons that filter the blood. When they become inflamed, they begin to damage the kidneys and lead to kidney failure. This is also among the causes of high EGFR levels.
In the monitoring of nephropathy—a common complication in patients with diabetes—an elevated GFR may indicate that the kidneys have sustained damage. In such cases, creatinine levels typically rise. In some cases, elevated GFR may be considered normal due to factors such as pregnancy, growth, and development. Therefore, whenever an abnormal GFR value is observed in test results—regardless of whether it is high or low—the results should be shown to a physician, and action should be taken based on the physician’s recommendation.
Causes of Low EGFR
Kidney damage is a major factor among the causes of low eGFR. The most significant cause of a decrease in this value is kidney damage. There are several indicators that point to this. These include: fatigue, itching, nausea, vomiting, high blood pressure, fluid retention, dry skin, difficulty concentrating, changes in urine output (increase or decrease), anemia, and associated symptoms such as early fatigue and palpitations—all of which may indicate kidney damage. These conditions are among the causes of a low EGFR.