Renal Panel

A renal panel may be used to evaluate kidney function, to help diagnose kidney-related disorders, to screen those who may be at risk of developing kidney disease or to monitor someone who has been diagnosed with kidney disease.

A healthcare practitioner may order a renal panel when someone has risk factors for kidney dysfunction such as high blood pressure (hypertension), diabetes, cardiovascular disease, obesity, elevated cholesterol, or a family history of kidney disease.

A healthcare practitioner may order a renal panel when someone has signs and symptoms of kidney disease, though early kidney disease often does not cause any noticeable symptoms. It may be initially detected through routine blood or urine testing. Examples of some signs and symptoms include:

• Swelling or puffiness, especially around the eyes or in the face, wrists, stomach, thighs or ankles
• Urine that is foamy, bloody, or coffee-colored
• A decrease in the amount of urine
• Problems urinating, such as a burning feeling or abnormal discharge during urination, or a change in the frequency of urination, especially at night
• Mid-back pain, below the ribs, near where the kidneys are located

A renal panel may also be ordered at regular intervals when someone is being treated for kidney disease for monitoring purposes.

Renal panel test results are not diagnostic but rather indicate that there may be a problem with the kidneys and that further testing is required to make a diagnosis and determine the cause. Results of the panel are usually considered together, rather than separately. Individual test result can be abnormal due to causes other than kidney disease, but taken together with risks and/or signs and symptoms, they may give an indication of whether kidney disease is present.

See the articles on the individual tests for more detailed information about each one:

• Electrolytes and anion gap
  • Sodium
  • Potassium
  • Chloride
  • Bicarbonate
• Phosphorus
• Calcium
• Albumin
• Urea/BUN and BUN/creatine ratio
• Creatinine
• Glucose
• eGFR

The results of your renal panel are interpreted by your healthcare provider within the context of other tests that you have had done as well as other factors, such as your medical history. A single result that is slightly high or low may or may not have medical significance. There are several reasons why a test result may differ on different days and why it may fall outside a designated reference range.

• Biological variability (different results in the same person at different times): If a healthcare practitioner runs the same test on you on several different occasions, there’s a good chance that one result will fall outside a reference range even though you are in good health. For biological reasons, your values can vary from day to day.
• Individual variability (differences in results between different people): Reference ranges are usually established by collecting results from a large population and determining from the data an expected average (mean) result and expected differences from that average (standard deviation). There are individuals who are healthy but whose tests results, which are normal for them, do not always fall within the expected range of the overall population.

Thus, a test value that falls outside of the established reference range supplied by the laboratory may mean nothing significant. Generally, this is the case when the test value is only slightly higher or lower than the reference range and this is why a healthcare practitioner may repeat a test on you and may look at results from prior times when you had the same test performed.

However, a result outside the range may indicate a problem and warrant further investigation. Your healthcare provider will evaluate your test results in the context of your medical history, physical examination, and other relevant factors to determine whether a result that falls outside of the reference range means something significant for you.

For more, read the articles on Reference Ranges and What They Mean and How Reliable is Laboratory Testing?

No, each test that is usually included in a renal panel may be run independently or along with different tests, depending on the purpose of the testing. For example, the electrolytes (sodium, potassium, chloride, and bicarbonate) may be run as an electrolyte panel as part of a routine health screen or to detect a potential problem with someone’s fluid or acid-base balance, which could be caused by heart disease, for example. The glucose test is also commonly performed to screen for, diagnose, and monitor diabetes.

Other laboratory tests that can be used to assess kidney function include:

• Urinalysis
• Urine protein
• Creatinine clearance

For people with diabetes or high blood pressure (hypertension), a urine albumin (microalbumin) test, which measures small amounts of albumin leakage from the blood into the urine, may also be used to detect early kidney damage. When both albumin and creatinine are measured in a random urine sample, an albumin/creatinine ratio (ACR) can be calculated. This may be done to more accurately determine how much albumin is escaping from the kidneys into the urine.

The National Kidney Foundation (NKF) and the National Kidney Disease Education Program (NKEDP) recommend two tests, in addition to blood pressure measurement, to screen for kidney disease in people with increased risk: urine protein (either urine albumin, urinalysis or urine total protein) and estimated glomerular filtration rate (eGFR).

When a structural problem is suspected, a variety of imaging tests can be used to evaluate the kidneys. A sample of kidney tissue, a biopsy, is sometimes helpful in diagnosing the specific cause of the problem. For more information, see the article on Kidney Disease.

Yes. Kidney disease often does not cause noticeable symptoms until late in the disease. That is why it is important, especially for those with risk factors for kidney disease, to have regular health exams so that any disorders or diseases that may affect the kidneys can be promptly addressed.

Yes. Since the tests included in the renal panel can have broad applications, abnormal results on one or more of the tests could indicate a problem other than kidney disease. Your healthcare provider will interpret the results of your renal panel tests by looking at all of your results, along with the results of any other tests you had performed as well as your symptoms, exam findings, and medical and family history.