What Are The Different Kidney Function Test Range?


Serum Creatinine

Serum creatinine measures how well your kidneys are clearing waste products and excess water from your blood. Healthy kidneys remove creatinine from the blood unchanged, but if they fail to do their job, creatinine levels will rise in your bloodstream and urine.

It is a good indicator in a normal kidney function test range, but it does vary from person to person. This is why it is not always a reliable indicator of kidney health and why the test is often compared to another test known as the glomerular filtration rate (GFR).

Creatinine clearance is measured by collecting a 24-hour urine sample and then comparing the amount of creatinine in the urine with that in your blood. The test results are reported as milliliters of creatinine per minute per body surface area (mL/min/BSA).

In men, normal levels range from 0.7 to 1.3 mg/dL; in women, they vary from 0.6 to 1.1 mg/dL. It is not uncommon for people to have higher or lower levels of creatinine, depending on their age, gender, and muscle mass.

Having a high level of creatinine can be a sign that you have kidney disease. It may be hard to diagnose, but symptoms can include bloody or dark urine, mid-backache, a change in urination frequency, loss of appetite, insomnia, and inability to concentrate.

Glomerular Filtration Rate (GFR)

Glomerular filtration rate (GFR) is one of the most important kidney function tests to diagnose and monitor chronic kidney disease. GFR helps doctors see how much damage the kidneys have done and how far the disease has progressed.

The test works by putting a needle into your arm to draw blood from your body. Some people feel a little pain or bruising after the test, but this is usually only temporary.

A machine tests your blood to make sure that everything is working properly. The machine uses a thin tube to measure the amount of fluid in your body and a tiny needle to take out blood from your arteries and veins.

Other factors that can affect your kidneys’ ability to filter blood include high cholesterol levels, blood pressure, and toxins in your diet.

Generally, your doctor will consider a GFR of over 90 to be normal for you. However, a GFR of 60 or lower can mean that you have kidney disease.

You can do a few things to improve your kidney function and decrease your risk of kidney disease. Your doctor can recommend a plan for keeping your kidneys healthy and your eGFR as high as possible.

Blood Urea Nitrogen (BUN)

Blood Urea Nitrogen (BUN) is used to measure how well your kidneys work. Your kidneys remove waste and extra fluid from your body, which helps prevent health problems like high blood pressure and anemia.

If your BUN level is higher than normal, it may indicate that your kidneys aren’t working properly. Other factors that can raise your BUN level include heart failure, dehydration, and a diet high in protein.

A BUN test can detect different conditions, from kidney disease to pregnancy. It is especially useful in diagnosing hypothyroidism and ornithine transcarbamylase deficiency.

If your doctor suspects you have kidney disease, they might recommend a BUN test along with other tests, such as a creatinine test. Your BUN results may also help identify the effectiveness of dialysis treatment.


Ultrasound is a noninvasive test that uses sound waves to look at tissues inside your body. A range of health professionals, such as obstetricians and rheumatologists, uses it.

It can be used to assess blood flow and check for kidney stones or other issues in the urinary tract. It may also be used to check for abnormalities in the heart or lungs.

A kidney ultrasound is a quick, painless procedure that takes about 20 minutes. You will be asked to lie still on an examination table, and the health professional will apply a clear gel to your skin.

An elevated level of urine albumin can indicate kidney disease. A result of 30 milligrams per deciliter (mg/dL) or less is normal, but anything higher is a sign that your kidneys are not doing their job properly.

CT Scan

A CT scan is a quick, painless procedure that uses X-rays to create detailed images of your body. It is typically used to diagnose problems like cancer, injuries, and kidney disease.

Unlike standard X-rays, a CT scan provides more detailed information about your internal organs and blood vessels, which can help doctors determine the cause of the problem. It also helps to show any abnormalities that may be present in your bones or joints.

Before having a CT scan, you may be given a special dye called a contrast to enhance the quality of the images. It is taken as a drink, passed into your enema (bowel), or injected into your bloodstream by an intravenous line.

The contrast dye is safe and will pass out of your body in your urine. But in some cases, you can react to the dye, which is usually mild and only causes itching or a rash.

You must tell your healthcare team about any food, medication, or seafood allergies and if you’ve ever had an allergic reaction to a contrast dye. The healthcare team will let you know if you need to avoid these things before the CT scan or if they can give you a test dose first to see if you react.