Estimated Glomerular Filtration Rate (eGFR): Test & Levels

The Estimated Glomerular Filtration Rate (eGFR) is a key blood test used to evaluate how well your kidneys are functioning. It measures how effectively the kidneys filter waste and excess fluids from the blood. Understanding what the estimated glomerular filtration rate is important, as it helps in identifying the early stages of kidney disease before symptoms become noticeable. Abnormal eGFR numbers may indicate underlying issues such as chronic kidney disease or kidney infection. For accurate diagnosis and treatment, consulting the best nephrologist in Bangalore at a trusted centre like SPARSH Hospitals, a leading nephrology hospital in Bangalore, is essential.

What is Estimated Glomerular Filtration Rate?

eGFR is a calculation based on the results of a blood test that measures creatinine levels. Creatinine is a waste product produced by muscle activity and filtered by the kidneys. High levels of creatinine in the blood may suggest that the kidneys are not filtering properly.

The eGFR calculation also takes into account age, gender, and body size to provide a more accurate picture of kidney function. By comparing results with the normal GFR by age and gender, doctors can determine whether the kidneys are functioning normally or if there is evidence of kidney damage.

At SPARSH, patients benefit from advanced diagnostic facilities and care from some of the best nephrologists in Bangalore to assess kidney health thoroughly.

What Do eGFR Numbers Mean?

The eGFR numbers mean different levels of kidney function and are used to classify the stages of kidney disease.

• 90 or above: Normal kidney function, but other signs may still indicate early kidney disease.
• 60–89: Mildly reduced kidney function; may not show symptoms but requires monitoring.
• 30–59: Moderate kidney damage; often associated with early chronic kidney disease.
• 15–29: Severe kidney damage; at high risk of complications and may need treatment planning.
• Below 15: Kidney failure; dialysis or a transplant may be necessary.

By understanding what these eGFR numbers mean, patients and doctors can take timely action to slow disease progression.

Symptoms of Kidney Problems

Declining kidney function often develops slowly and may not cause symptoms in the early stages. However, some common signs that may suggest worsening kidney function include:

Fatigue and Weakness

When kidneys fail to remove waste effectively, toxins build up in the blood, leading to constant tiredness.

Swelling in Legs and Ankles

Fluid retention due to poor kidney function can cause noticeable swelling in the lower limbs.

Changes in Urination

Frequent urination, foamy urine, or blood in urine can signal kidney issues.

Persistent Nausea and Vomiting

Buildup of waste products in the blood may cause digestive discomfort.

Shortness of Breath

Excess fluid in the lungs due to kidney problems can lead to breathing difficulties.

If you experience these symptoms, it is important to consult the best nephrologist in Bangalore for timely evaluation.

What Causes Low eGFR Levels?

There are several causes that can lower eGFR values and affect kidney health, including:

• Chronic Kidney Disease: Progressive damage to the kidneys over time.
• Kidney Infection: Infections can cause temporary or permanent kidney injury.
• Diabetes and Hypertension: Two of the leading causes of reduced kidney function.
• Dehydration: Severe dehydration can temporarily lower eGFR.
• Certain Medications: Some drugs can impact kidney function and lower GFR levels.
• Ageing: eGFR naturally declines with age, which is why knowing the normal GFR by age and gender is important.

At SPARSH Hospitals, specialists ensure accurate diagnosis to differentiate between temporary changes in eGFR and chronic conditions.

Stages of Kidney Disease

Kidney disease is often classified into five stages of kidney disease based on eGFR results:

• Stage 1 (eGFR ≥ 90): Normal kidney function but with evidence of mild damage.
• Stage 2 (eGFR 60–89): Mild decrease in function; often requires monitoring and lifestyle adjustments.
• Stage 3 (eGFR 30–59): Moderate damage, patients may begin to show symptoms like fatigue and swelling.
• Stage 4 (eGFR 15–29): Severe kidney impairment, higher risk of complications, requiring specialist intervention.
• Stage 5 (eGFR < 15): Kidney failure, requiring dialysis or kidney transplant.

Early detection of these stages ensures better outcomes and slows disease progression.

Treatment for Low eGFR Levels

Treatment depends on the cause of reduced eGFR and the stage of kidney disease. Key approaches include:

Lifestyle Modifications

Adopting a kidney-friendly diet, reducing salt intake, and staying hydrated support better kidney function.

Medications

Drugs may be prescribed to control blood pressure, diabetes, and cholesterol, which are major contributors to kidney disease.

Treating Kidney Infections

Prompt treatment of kidney infections with antibiotics prevents long-term damage.

Dialysis and Transplant

For advanced cases of chronic kidney disease, dialysis or kidney transplant may become necessary.

At SPARSH Hospitals, recognised as the best nephrology hospital in Bangalore, patients receive comprehensive care tailored to their stage of disease.

Prevention of Kidney Disease

While not all causes can be prevented, steps can be taken to maintain healthy kidney function and normal eGFR:

• Regular Health Check-ups: Periodic monitoring of kidney function with eGFR tests.
• Manage Diabetes and Hypertension: Keeping these conditions under control lowers the risk of kidney damage.
• Stay Hydrated: Drinking enough fluids helps the kidneys filter waste effectively.
• Avoid Overuse of Painkillers: Excessive use of NSAIDs can harm kidney function.
• Maintain a Healthy Weight: Obesity increases the risk of chronic kidney disease.

When to See a Doctor?

You should consult a kidney specialist if:

• Your eGFR results are consistently below the normal range.
• You experience persistent fatigue, swelling, or changes in urination.
• You have diabetes, hypertension, or a family history of kidney disease.
• You’ve had recurring kidney infections.

You can visit SPARSH Hospitals for expert advice from the best nephrologist in Bangalore. Choosing a trusted nephrology hospital in Bangalore ensures access to advanced diagnostic tests and comprehensive kidney care.

Conclusion

The Estimated Glomerular Filtration Rate (eGFR) is one of the most reliable indicators of kidney health. By understanding what eGFR numbers mean, doctors can identify the stages of kidney disease and take early action to prevent complications. Regular monitoring, timely treatment, and healthy lifestyle choices are key to maintaining kidney function.

SPARSH Hospitals, widely recognised as the best nephrology hospital in Bangalore, provides world-class care with guidance from some of the best nephrologists in Bangalore. If you are concerned about kidney function, consult SPARSH for accurate diagnosis, effective treatment, and long-term kidney health.

Frequently Asked Questions

Can eGFR improve with lifestyle changes?

Yes, in many cases, eGFR can improve if the decline was due to reversible factors such as dehydration, high blood pressure, or uncontrolled diabetes. Adopting a kidney-friendly diet, staying hydrated, controlling blood sugar and blood pressure, and avoiding excessive use of painkillers can help improve kidney function.

Is the eGFR test enough to diagnose kidney disease?

No, while eGFR is a critical marker of kidney function, it is usually combined with other tests such as urine analysis (to check for protein or blood in urine), imaging scans, and blood pressure checks. Together, these give a complete picture of kidney health.

How often should eGFR be tested?

The frequency depends on your health status. For healthy adults, routine annual health check-ups may include eGFR testing. People with risk factors like diabetes, hypertension, or family history of kidney disease may need more frequent testing, as advised by their doctor.

Does age affect eGFR results?

Yes, eGFR naturally declines with age, even in people without kidney disease. This is why doctors interpret results based on the normal GFR by age and gender. A lower eGFR in elderly patients may be normal, while in younger individuals it could suggest kidney disease.

Can medications affect eGFR levels?

Yes, certain medicines such as antibiotics, chemotherapy drugs, and NSAIDs (painkillers) can affect kidney function and lower eGFR. It’s important to inform your doctor about any medications you are taking before testing.

What lifestyle changes support healthy kidney function?

To maintain healthy eGFR levels, adopt habits such as eating a balanced diet low in salt and processed foods, exercising regularly, staying hydrated, avoiding smoking, and limiting alcohol intake.

Is dialysis always required when eGFR is low?

Not always. Dialysis is generally considered when eGFR drops below 15 and symptoms of kidney failure appear. In earlier stages, lifestyle management, medication, and regular monitoring can help slow the progression of kidney disease.