What is eGFR?

High eGFR indicates that the kidneys are filtering blood faster than normal. However, this is not always a positive sign.

• Overactive Kidneys: High eGFR may indicate that the kidneys are overactive and filtering blood more quickly than normal.
• Hyperfiltration: This condition is especially seen in individuals with diabetes or obesity and can lead to kidney damage.
• Early-Stage Kidney Disease: In some early-stage kidney diseases, the kidneys may work excessively before damage occurs, causing an elevated eGFR.
• False Positive Result: eGFR calculations can vary depending on factors such as age, sex, and muscle mass. Therefore, in some cases, a high eGFR result may be a false positive.

High eGFR (estimated glomerular filtration rate) means the kidneys are filtering blood faster than normal. However, this is not always a positive sign. Here are the possible causes of high eGFR:

• Early-Stage Kidney Disease (Hyperfiltration): Especially in individuals with diabetes or obesity, the kidneys may work excessively before damage occurs, raising eGFR. This condition, called hyperfiltration, can lead to kidney damage.
• Pregnancy: Kidney function may temporarily increase during pregnancy, which can elevate eGFR.
• High-Protein Diet: Diets high in protein can cause the kidneys to work harder, increasing eGFR.
• Certain Medications: Some medications can affect kidney function and raise eGFR.
• Intense Exercise: Engaging in intense exercise or an excessively active lifestyle can trigger eGFR elevation.
• Dehydration (Fluid Loss): Significant fluid loss in the body, known as dehydration, can increase eGFR.
• Increased Muscle Mass: In some cases, increased muscle mass in the body can elevate eGFR values.
• Physiological Changes: In young, healthy individuals, eGFR may naturally be higher than normal.

High eGFR (estimated glomerular filtration rate) usually does not cause noticeable symptoms, as it is not a disease on its own but an indicator of kidney function. However, depending on the underlying conditions causing high eGFR, some symptoms may appear.

Low eGFR (estimated glomerular filtration rate) means that the kidneys are not filtering blood effectively, indicating reduced kidney function.

Here’s what you need to know about low eGFR:

Meaning of Low eGFR:

• The kidneys are unable to filter blood adequately and remove waste from the body.
• It indicates decreased kidney function or the presence of kidney disease.
• It can be a sign of serious kidney problems, such as chronic kidney disease (CKD).

Low eGFR (estimated glomerular filtration rate) means that the kidneys are not filtering blood adequately. This indicates reduced kidney function and the potential presence of kidney disease.

Various factors can cause low eGFR:

• Chronic Kidney Disease (CKD): Gradual kidney damage and decreased function over time. This is the most common cause of low eGFR.
• Acute Kidney Injury (AKI): Sudden damage to the kidneys due to conditions such as infections, medications, or trauma.
• Diabetes: High blood sugar can damage kidney blood vessels, reducing kidney function.
• High Blood Pressure (Hypertension): Uncontrolled high blood pressure can harm kidney blood vessels.
• Glomerulonephritis: Inflammation of the glomeruli, the filtering units of the kidneys.
• Polycystic Kidney Disease: A genetic condition causing cysts to form in the kidneys.
• Urinary Tract Obstruction: Conditions that block urine flow from the kidneys, such as kidney stones or tumors.
• Certain Medications: Some drugs can damage the kidneys, leading to a decrease in eGFR.
• Aging: Kidney function gradually declines with age.
• Dehydration: Excessive fluid loss can impair the kidneys’ ability to filter properly.

Important Note: Low eGFR is not always a sign of disease, but it should be monitored under medical supervision.

Low eGFR (estimated glomerular filtration rate) indicates that the kidneys are not filtering blood adequately. This reflects reduced kidney function and may signal serious kidney problems such as chronic kidney disease (CKD). Low eGFR usually does not cause noticeable symptoms in the early stages. Symptoms appear as kidney function declines and CKD progresses.

Possible symptoms of low eGFR include:

• Fatigue and Weakness: Reduced production of the hormone erythropoietin by the kidneys can cause anemia, leading to fatigue.
• Changes in Urine Output: Increased or decreased urine volume, especially frequent urination at night.
• Edema (Swelling): Fluid retention due to inadequate kidney filtration can cause swelling in the ankles, legs, or around the eyes.
• Itching: Accumulation of waste products can cause skin itching.
• Loss of Appetite and Nausea/Vomiting: Reduced kidney function can lead to nausea and vomiting.
• Muscle Cramps: Electrolyte imbalances may result in muscle cramps.
• Sleep Problems: Kidney failure can negatively affect sleep quality.
• Difficulty Concentrating: Impaired kidney function can affect brain performance.
• High Blood Pressure (Hypertension): Kidneys play a key role in regulating blood pressure, and decreased function can lead to hypertension.

The eGFR (estimated glomerular filtration rate) blood test is performed to assess how well the kidneys are functioning. This test is especially requested for individuals suspected of impaired kidney function or those at risk for kidney disease.

Reasons for performing the eGFR blood test include:

• Assessing Kidney Function:
  • eGFR measures how effectively the kidneys filter blood, providing an overall evaluation of kidney function.
• Diagnosing and Monitoring Chronic Kidney Disease (CKD):
  • eGFR is used for the early detection of CKD and monitoring its progression.
  • It helps determine the stages of CKD.
• Determining Risk of Kidney Damage:
  • eGFR monitoring is important in conditions that increase the risk of kidney damage, such as diabetes, high blood pressure, and heart disease.
• Adjusting Medication Dosages:
  • Some medications are excreted through the kidneys. eGFR helps adjust drug dosages according to kidney function.
• Kidney Transplant Evaluation:
  • eGFR is a key parameter for monitoring kidney function in transplant candidates and post-transplant patients.
• Investigating the Cause of Symptoms:
  • If certain symptoms suggest kidney problems, a doctor may order an eGFR blood test.

The eGFR blood test is an important tool for assessing kidney health and enabling the early diagnosis of kidney diseases.

eGFR (estimated glomerular filtration rate) is a blood test that shows how well the kidneys are functioning. This test is used to evaluate kidney function and diagnose chronic kidney disease (CKD). eGFR values help determine the stages of kidney function.

Here are the eGFR blood values and their meanings:

• 90 mL/min/1.73 m² or higher:
  Normal kidney function.

• 60-89 mL/min/1.73 m²:
  Mild kidney damage.

• 45-59 mL/min/1.73 m²:
  Moderate kidney damage.

• 30-44 mL/min/1.73 m²:
  Moderate to severe kidney damage.

• 15-29 mL/min/1.73 m²:
  Severe kidney damage.

• Less than 15 mL/min/1.73 m²:
  Kidney failure.

Important Notes:

• eGFR values can vary depending on factors such as age, gender, and muscle mass.
• eGFR alone is not a diagnostic tool. Doctors interpret eGFR values together with other blood and urine tests and clinical findings.
• eGFR values tend to be lower in elderly individuals. Therefore, your doctor evaluates all test results collectively.

This information is for general educational purposes and does not replace medical advice. If you have concerns about your blood values, it is important to consult a doctor.