How are your kidneys? Let's find out with the (eGFR) test!

Have you ever seen a value called `(eGFR)` on a blood test report? Perhaps a doctor has told you about this. Although it may seem a bit complicated to many people, `(eGFR)` is actually a simple test that tells us a lot of important information about the health of our kidneys. So, today we will talk about many things in simple terms, such as what `(eGFR)` is, what it can tell us, and who it is important to.

What are kidneys? What does `(eGFR)` actually mean?

Simply put, our kidneys are like two tiny filters in our body. These have millions of other tiny filters called `(glomeruli)`. These are the ones that filter the unwanted waste and toxins in our blood and then excrete them as urine. Think of it like a water filter cleaning water.

Now, this `Estimated Glomerular Filtration Rate (eGFR)` is a value that measures how much blood is purified per minute by the filters called `(glomeruli)` in your kidneys, relative to your body size. Usually, when you do a blood test, you get this `(eGFR)` value as part of the `(basic metabolic panel)`.

This `(eGFR)` value is very important for doctors to identify if there is any problem with your kidneys, especially kidney disease . Our kidneys are a very important part of the urinary system . When kidney disease occurs, the speed at which these filters clean the blood decreases. Then, harmful toxins start to accumulate in the blood.

Unfortunately, symptoms of kidney disease, such as frequent urination and muscle cramps, may not appear until the kidneys have lost about 40% of their function. That's why the eGFR test is important. It can detect the disease early and start treatment to slow or stop the damage to the kidneys.

Who is this `(eGFR)` test most important for?

Doctors use the eGFR test to see if kidney disease has started, as well as to determine the stage of the disease in someone who already has kidney disease.

People with certain health conditions are at higher risk of developing kidney problems. If you have any of these conditions, or are taking medication for them, your doctor may monitor your kidney health regularly using an eGFR test:

• If you have birth defects that affect kidney function.
• If you have coronary artery disease or heart disease .
• If you have diabetes (Diabetes Mellitus) .
• If anyone in the family has had kidney disease .
• If you have frequent urinary tract infections (UTIs) or urinary blockages .
• If you have high blood pressure .
• If you have a history of smoking .
• If you are obese .

It is very important for people with these risk factors to be aware of their eGFR value.

How do doctors find this `(eGFR)` value?

In fact, tests that accurately measure the rate at which the kidneys filter blood (GFR) are very complex. That's why they're usually only done on a research basis or in special cases, like kidney transplants. Instead, doctors use a formula to find an estimated value, called an ``eGFR''. This formula is based on the results of your ``serum creatinine'' blood test, along with information like your age and gender .

Now, what is this `(serum creatinine)` blood test ? It measures the level of a waste product called `(creatinine)` in your blood. Our body produces a chemical called `(creatinine)`, which is what gives our muscles energy. When our muscles use this energy, the muscle tissue breaks down, and a toxic waste product called `(creatinine)` is released into the blood. Healthy kidneys filter this toxic product called `(creatinine)` from the blood and it is excreted from the body when you urinate. However, when you have kidney disease, this `(creatinine)` stays in the blood and starts to accumulate little by little.

To calculate your eGFR, your doctor will use something like the National Kidney Foundation's calculation system. This is affected by the following factors:

• Your creatinine level.
• Age.
• Gender.
• Height and weight.
• Race and/or ethnicity (this also affects some calculations).

What should you do before a `(Serum Creatinine)` blood test?

This `(serum creatinine)` blood test is very sensitive. Therefore, you should follow your doctor's instructions carefully before the blood test. You may be asked to fast (fast) , which means drinking only liquids and not eating solid foods, for a period of time before the test. You may also be asked to stop taking certain medications for a while.

Another thing is that your doctor may also advise you to avoid eating cooked meat the day before the test. Some studies have shown that eating meat can temporarily increase creatinine levels. So, it is better to be careful about these things to get accurate results.

What do `(eGFR)` values ​​mean?

Doctors measure eGFR in milliliters per minute, divided by body surface area (mL/min/1.73m2) .

`(eGFR)` values ​​can vary depending on age, gender, and other factors. This value naturally decreases slightly as we age and lose muscle mass. For example, while the average `(eGFR)` value for a 20-year-old is about 116 mL/min/1.73m2, it may decrease to about 85 mL/min/1.73m2 for a 60-year-old.

Generally, an ``eGFR'' value greater than 60 means that your kidney function is at least 60%. The higher the value, the better the kidney function is considered.

You may see two `(eGFR)` values ​​in your report, one for blacks and one for non-blacks. Some studies have shown that people of African descent have slightly higher `(creatinine)` production and muscle mass than others, so their `(eGFR)` value may also be higher. Since the lab does not know your ethnicity, sometimes both values ​​are sent in the report. However, this may not be very relevant for us in Sri Lanka, but it is good to know. The most important thing is that your doctor explains your report accurately.

What is the relationship between eGFR and kidney disease?

If your eGFR is below 60 for three consecutive months , your doctor may diagnose you with chronic kidney disease .

There are five main stages of this kidney disease:

• Stage 1 (eGFR 90 or higher): This means that there may be some minor damage to the kidneys, but the kidneys are still working well.
• Stage 2 (eGFR between 60 and 89): This means that the kidneys have been damaged a little more than stage 1, but they are still functioning well.
• Stage 3 (eGFR between 30 and 59): This means that kidney function has decreased. Some symptoms may occur at this stage.
• Stage 4 (eGFR between 15 and 29): This means that kidney function is very poor, with moderate to severe kidney damage.
• Stage 5 (eGFR less than 15): This is a sign of kidney failure . This means your kidneys are working less than 15%. This stage is the most dangerous and can be life-threatening. These people may need dialysis (cleansing the blood with a machine) or a kidney transplant .

Don't be afraid, once you know about this stage. The important thing is that even if the `(eGFR)` value is low, if it is detected early and proper treatment and lifestyle changes are made, the damage to the kidneys can be controlled to a large extent.

What are the next tests if the `(eGFR)` value is abnormal?

If your eGFR is abnormal, your doctor may order one or more of these tests to assess the extent of kidney damage and to find the cause of the abnormality:

• Urinalysis: Checks for albumin (a type of protein) and blood in the urine. These can be early signs of kidney disease.
• Kidney ultrasound or CT scan: Check for kidney stones, kidney cancer, or other problems with the urinary tract.
• Creatinine clearance test: Measures creatinine levels in urine and blood at the same time.
• Kidney biopsy: Know exactly the type and severity of kidney disease.

The best treatment for you will be determined based on the information obtained from these tests.

What time should I see a doctor?

If you have kidney disease, or have risk factors for kidney disease, see a doctor immediately if you experience any of these symptoms:

• If you need to urinate frequently, if you have blood in your urine, or if your urine is foamy.
• If the skin is dry, itchy, or has a dark color.
• If you feel very tired .
• If the muscles are twitching and the body feels like it is cramping.
• If you have nausea or vomiting .
• If you have difficulty breathing .
• If your hands, feet, or ankles are swollen .

Do not ignore these symptoms. It is very important to seek medical advice immediately.

The most important thing - things we need to remember (Take-Home Message)

Okay, so we've talked a lot about `(eGFR)` now, haven't we?

Remember, if you are at risk of developing kidney disease, or if you already have kidney disease, it is very important to monitor your ``eGFR`` value regularly. This also applies to those taking certain medications.

If your eGFR shows some degree of kidney disease, you can take steps to protect your kidneys from further damage. Your doctor may prescribe medication for high blood pressure or diabetes. You can also improve kidney health by losing weight (if necessary), exercising, and eating a nutritious, low-salt diet .

So, keep an eye on your `(eGFR)` value. If you have any questions or doubts, don't be afraid to ask your doctor. Two healthy kidneys are a big boost to a healthy life!

` Kidney, eGFR, creatinine, kidney disease, blood test, health, urine test