Creatinine Clearance Calculator

How does this creatinine clearance calculator work?

This is a health tool directed towards the kidney function that assesses the amount of creatinine filtered by the kidneys based on Cockcroft Gault equation.

Once you enter your gender, height, weight and serum creatinine, as provided through any specialized blood test, the creatinine clearance calculator will display you the creatinine clearance in ml/min and also the ideal body weight based on Devine’s formula so you know where you stand.

■ If the serum creatinine is expressed in mg/dL Cockcroft and Gault equation formula is:

CrCl for male = [(140 - age) * Weight in kilograms] / (Serum Creatinine in mg/dL * 72) 

CrCl for female = [(140 - age) * Weight in kilograms * 0.85] / (Serum Creatinine in mg/dL * 72)

■ If the serum creatinine is expressed in µmol/L:

CrCl for male = [(140 - age) * Weight in kilograms * 1.23] / (Serum Creatinine in µmol/L)  

CrCl for female = [(140 - age) * Weight in kilograms * 1.04] / (Serum Creatinine in µmol/L)

■ The calculation of the ideal body weight by Devine’s formula:

Male = 50 kg + (2.3 * (Height in inches - 60))

Female = 45.5 kg + (2.3 * (Height in inches - 60))

The Devine’s formulas presented above returns the ideal body weight in kilograms. In order to get the ideal body weight in lbs the calculator automatically does the conversion from kilograms to lbs (1 kilogram = 2.20462262 pounds).

Example calculation

Let’s take the case of a 46 year old male, weighing 215 lbs at a height of 6ft 2in and with a value of serum creatinine of 1.8 mg/dl. The result is:

- The estimated creatinine clearance rate (eCCr): 70.73 ml/min

- The estimated ideal body weight: 181.23 lbs or 82.20 kg.

What is creatinine clearance?

This is a breakdown product of creatine, an important component found in muscles that is cleared through the kidneys so its clearance is an important indicator of the kidneys’ filtering function.

If kidneys don’t filter creatinine well its blood levels increase. This is usually measured in milliliters/ minute (ml/min) and normal values are around 98-136 ml/min for males and 88-128 ml/min for females.

In general healthy adults have levels of creatinine clearance ranging 80-130 ml/min.

A low level suggests damage to the kidneys, kidney failure, and different circulatory obstructions and can even indicate heart failure.

Some people only find out about their condition after routine exams because of these elevated levels but there are some symptoms of kidney failure that are obvious and should be taken in consideration such as dehydration, fatigue, edema, shortness or breath and even nausea or vomiting.

Remember that the results from the calculator are for informational purposes only and you should ask for professional advice and explanation result.

References

1) Cockcroft DW, Gault MH. (1976) Prediction of creatinine clearance from serum creatinine. Nephron; 16(1):31-41.

2) Gault MH, Longerich LL, Harnett JD, Wesolowski C. (1992) Predicting glomerular function from adjusted serum creatinine. Nephron; 62(3):249-56.