BUN / Creatinine Ratio (Serum)

Specimen Required

3 Clotted Blood Samples

Fasting Required

Purpose of the Test

BUN/Creatinine Ratio test is typically ordered as a part of a basic metabolic panel (BMP) to assess the kidney function, especially in people with risk factors for kidney disease such as hypertension, diabetes, or family history of kidney disease. The test is also used to monitor the kidney function in people with kidney disease.

When this test is required

The BUN/Creatinine Ratio test is usually ordered as a part of a BMP, which is routinely done as a part of a general health check-up. It may also be ordered when a person has symptoms or risk factors suggestive of kidney disease, such as high blood pressure, diabetes, or family history of kidney disease.

What the Test Detects

The BUN/Creatinine Ratio test measures the ratio of two substances, blood urea nitrogen (BUN) and creatinine, in the blood. BUN is a waste product formed in the liver, which is filtered out of the blood by the kidneys and excreted in the urine. Creatinine is a waste product produced by the muscles, which is filtered out of the blood by the kidneys and excreted in the urine. The ratio of BUN to creatinine in the blood is a measure of kidney function.

Preparation for the Test

Typically, no special preparation is required for the BUN/Creatinine Ratio test. However, fasting for 8-12 hours before the test may be required in some cases.

Sample Requirements

A blood sample is required for the BUN/Creatinine Ratio test.

Additional Notes

The BUN/Creatinine Ratio test is a useful screening tool for assessing kidney function, but it should not be used as the sole criterion for diagnosing kidney disease. Other tests, such as a urine albumin test or a glomerular filtration rate (GFR) test, may also be required to fully evaluate kidney function.

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