Urea nitrogen/Creatinine

ChemistryAlso known as: BUN/Creat BldAlso known as: BUN/Creat SerPlAlso known as: Urea nit/Creat Fldg/g{creat}

Calculates the ratio of two kidney waste products to assess kidney function patterns.

Normal Range
Consult your provider
g/g{creat}
Abnormal Levels
Consult your provider
Specimen Type
Blood

Why This Biomarker Matters

The BUN/creatinine ratio identifies the underlying cause of kidney problems, distinguishing dehydration from true kidney disease and guiding appropriate treatment.

Overview

This test calculates the ratio of blood urea nitrogen (BUN) to creatinine, both waste products filtered by the kidneys. The ratio helps distinguish different causes of abnormal kidney function. A high ratio may suggest dehydration, excessive protein breakdown, or reduced kidney blood flow, while a low ratio can indicate liver disease or malnutrition. This ratio is more informative than either value alone in determining kidney dysfunction patterns.

Technical Information (LOINC Codes)

Standardized laboratory codes for this biomarker

3097-3Primary
Urea nitrogen/Creatinine [Mass Ratio] in Serum or Plasma
mg/mg{creat}
44734-2
Urea nitrogen/Creatinine [Mass Ratio] in Blood
g/g{creat}
13821-4
Urea nitrogen/Creatinine [Mass Ratio] in 24 hour Urine
g/g{creat}
44416-6
Urea nitrogen/Creatinine [Mass Ratio] in Urine
g/g{creat}
44735-9
Urea nitrogen/Creatinine [Mass Ratio] in Body fluid
g/g{creat}