What Drugs Come Up on a Drug Test

November 29, 2021

11 Things to Know Before Getting an EGFR Test

CC0/DarkoStojanovic/Pixabay

Your doctor may recommend that you need to have an eGFR test. If this is the case, here are 11 things you need to know before you get your eGFR test.

What is EGFR?

The term eGFR stands for estimated glomerular filtration rate, as confirmed by Verywell Health. Your kidneys, which act as the main system of filtration for your body, contain small filters called glomeruli, which are primarily used to clean your blood. These don't operate as effectively as normal if your kidneys aren't working properly.

CC0/Belova59/Pixabay

What Is an EGFR Test?

To check how well your kidneys work, your doctor may order an eGFR test. This simple blood test measures the creatinine levels in your blood and, by way of a formula, ascertains how efficiently your kidneys are working, according to Verywell Health.

CC0/Belova59/Pixabay

Is Only One EGFR Test Necessary?

If you have previously been diagnosed with kidney disease, you will need regular eGFR tests to monitor your kidneys' performance, as stated by Verywell Health. As there aren't any symptoms for early stages of kidney disease, you'll have regular eGFR tests if you have a family history of this disease or other conditions, such as high blood pressure, diabetes and cardiovascular disease.

CC0/iggy7117/Pixabay

Symptoms Relating to Kidney Disease

If you have difficulty urinating or your urine is foamy, these can be symptoms of kidney disease, as stated by Healthline. Other symptoms are mid-back pain and swelling in your body that cannot be explained.

CC BY-SA 2.0/Simon James/Flickr

Early Intervention Is Recommended

To avoid causing further damage to your kidneys, take the test if you are suffering from certain conditions. These include kidney stones, recurring urinary tract infections, blood in your urine, hypertension, kidney failure, difficulty urinating, diabetes, polycystic kidney disease or heart disease, as stated by Healthline.

CC0/nile/Pixabay

How to Prepare for an EGFR Test

As blood is taken from your arm, it's best to wear loose clothing allowing you to roll your sleeve up easily or a sleeveless top. Other than that, there is nothing else to prepare for your test unless your doctor specifies that you cannot take particular medications, must stop eating particular foods or must not eat at all on the day that you have your test, as claimed by Verywell Health.

CC BY-SA 2.0/Amy Douglas/Flickr

What Information Is Needed to Calculate Your GFR?

A formula is used to mathematically calculate your GFR but other factors are taken into account to ensure the accuracy of the test results. These factors include your height, weight, age, race and sex, as stated by Healthline.

CC0/geralt /Pixabay

Side Effects of an EGFR Test

Common side effects include a slight throbbing or stinging sensation, swelling or bruising and dizziness or lightheadedness. Serious side effects can include getting an infection, having excessive bleeding or having an area that becomes swollen and is filled with blood, as claimed by Verywell Health.

CC BY-SA 2.0/Steve Zerr/Flickr

Medications That Affect Your Creatinine Level

Your kidneys help to filter creatinine from your body so a high level found in your blood in the test results means your kidneys might not be working properly. Some medications affect the levels of creatinine so it's important to let your doctor know if you're taking them. These include ibuprofen for older adults, cisplatin, trimethoprim, cephalosporin antibiotics, cimetidine, flucytosine and aminoglycoside antibiotics, as confirmed by Healthline.

CC0/Vnukko/Pixabay

Factors That Can Influence an EGFR Test

Many factors influence eGFR tests and these can affect the accuracy of the results. Your doctor will take these factors into account and they include being under 18, being pregnant, being elderly, having a vegetarian or vegan diet and being considerably more or less muscular in shape than is deemed average, as confirmed by Verywell Health.

CC0/Pexels/Pixabay

How to Interpret the Results

Your result is given as a number and the National Kidney Foundation categorizes the number in five stages of kidney damage. GFR 90 or above (stage one) means your kidney function is high or normal, GFR 60 to 89 (stage two) means your kidneys are functioning at a mild loss, GFR 30 to 59 (stage three) means you have a moderate reduction in your level of kidney function, GFR 15 to 29 (stage four) means your kidneys are functioning at a severe loss and GFR 15 or below (stage five) means you are suffering from kidney failure, as confirmed by Healthline.

Public Domain Mark 1.0/Presidio of Monterey/Flickr

Disher Swers1985