BUN Creatinine Ratio Calculator

intrinsic renal cause = 10 : 1

Blood Urea Nitrogen - BUN:

mg/dL ▾

BUN Creatinine Ratio:

mg/dL ▾

Related

The BUN Creatinine Ratio Calculator measures the ratio of blood urea nitrogen (BUN) to creatinine, which is essential for diagnosing the causes of acute renal failure and evaluating kidney function.

What is BUN/Creatinine Ratio?

The BUN Creatinine Ratio is an important indicator of kidney functionality. BUN (Blood Urea Nitrogen) and Creatinine are substances produced by metabolism:

BUN: Filtered by the nephrons in the kidneys and partially reabsorbed back into the blood.
Creatinine: Primarily filtered out through urine.

Calculating the BUN/Creatinine ratio helps assess kidney health. Abnormal kidney function can lead to a higher BUN/Creatinine ratio.

BUN Creatinine Ratio

How is Urea Produced?

Urea is a liver waste product produced when the body digests protein. It is filtered by the kidneys, and its filtration rate can be measured using a protein creatinine ratio calculator. High urea levels in the blood may indicate kidney dysfunction or azotemia.

How to Calculate BUN Creatinine Ratio?

You can calculate the BUN/Creatinine ratio through a blood test. Blood tests provide valuable information about your metabolism, kidney and liver function, and overall health.

Formula:

BUN / Creatinine Ratio = Serum BUN ÷ Serum Creatinine

The BUN/Creatinine ratio is measured in serum separated from blood. Both US units and SI units can be used to calculate it. Below are the reference normal levels:

BUN (Normal Range): 7–20 mg/dL
Creatinine (Normal Range): 0.6–1.3 mg/dL
Normal BUN/Creatinine Ratio: 10:1 to 20:1

The BUN Creatinine Ratio Calculator helps measure the ratio of Blood Urea Nitrogen (BUN) to Creatinine, which is crucial for assessing kidney function and identifying potential causes of acute renal failure.

Normal BUN and Creatinine Levels

Parameter	US Units Range	SI Units Range
Blood Urea Nitrogen (BUN)	7 – 30 mg/dL	2.5 – 10.7 mmol/L
Creatinine	0.7 – 1.2 mg/dL	62 – 106 μmol/L

BUN/Creatinine ratio: 10:1
On normal diet: 12–16
Optimum adult level: 15.5

These normal levels can be measured using a BUN Creatinine Ratio Calculator.

Causes of BUN/Creatinine Ratio Disturbance

The BUN/Creatinine ratio can be altered due to dehydration, malnutrition, or high protein intake. The ratio helps distinguish between prerenal and intrinsic renal causes:

BUN/Creatinine ratio >20: Suggests a prerenal cause
BUN/Creatinine ratio <10: Suggests an intrinsic renal cause

BUN/Creatinine >20 (Prerenal)	BUN/Creatinine <10 (Intrinsic Renal)
Dehydration	Malnutrition
Hypovolemia	Pregnancy
High protein intake	Acute tubular necrosis
Congestive heart failure	SIADH (Syndrome of Inappropriate ADH)
Heart attack	Rhabdomyolysis
Gastrointestinal bleeding	---