Pediatric Creatinine Clearance Calculator
Utilizing Three Clearance Models plus updated Schwartz equation
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Enter Data Below
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Patient Name:
Room:
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Age:
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Scr: Height:
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Background:
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Program is based on the following equations:
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Schwartz equation: CrCl
(ml/min/1.73m2)=
[length (cm) x k] / Scr
(Patient population: infants over 1 week old through adolescence (18 years old))
k = 0.45 for infants 1 to 52 weeks old
k = 0.55 for children 1 to 13 years old
k = 0.55 for adolescent females 13-18 years old
k = 0.7 for adolescent males 13-18 years old
Schwartz GJ, Haycock GB, Edelmann CM Jr, Spitzer A: A simple estimate of glomerular filtration rate in children derived from body length and plasma
creatinine. Pediatrics 58:259-263, 1976. |
Updated Schwartz ("Bedside Schwartz") formula:
eGFR = 0.413 x (height/Scr) if height expressed in centimeters
or 41.3 x
(height/Scr) if height expressed in meters
eGFR (estimated glomerular filtration rate) = mL/min/1.73 m2
This equation was updated in 2009 and is the best method for estimating
GFR in children from 1 to 18 years old. This equation assumes the
use of creatinine methods with calibration traceable to IDMS.
The Schwartz formula was devised in the mid-1970s to estimate GFR in
children. Recent data suggest that this formula currently overestimates
GFR as measured by plasma disappearance of iohexol, likely a result of a
change in methods used to measure creatinine.
Source: Schwartz GJ, Muñoz A, Schneider MF, et al. New
equations to estimate GFR in children with CKD. J Am Soc Nephrol.
2009;20(3):629-37. |
Shull et al: Crcl (ml/min/1.73m2) = ((0.035 x age) + 0.236) x 100)/
Scr
Shull BC, Haughey D, Koup JR, Baliah T, Li PK. A useful method for predicting creatinine clearance in children. Clin Chem. 1978 Jul;24(7):1167-9. |
Counahan-Barratt: GFR (ml/min/1.73m2) = ( 0.43 x length )/ Scr
Counahan R, Chantler C, Ghazali S, Kirkwood B, Rose F, Barratt TM. Estimation of glomerular filtration rate from plasma creatinine concentration in children.
Arch Dis Child. 1976 Nov;51(11):875-8. |
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Important Considerations:
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Clinical application and reliability. Several factors can reduce the
accuracy of creatinine clearance predictive models such as
concomitant disease states and medical procedures. The article below
represents a common theme found in several other studies that
examine the clinical utility of the various CRCL predictive models
when complicating factors exist.
Jacobson P, West N, Hutchinson RJ. Predictive ability of
creatinine clearance estimate models in pediatric bone marrow
transplant patients. Bone Marrow Transplant. 1997 Mar;19(5):481-5.
"In the majority of children, models overestimated CrCl. The tested
models did not accurately predict CrCl and did not provide a
reliable alternative to measured CrCl." (Models assessed: Traub
and Johnson, Schwartz et al, Counahan et al, modified Counahan et
al, Ghazali and Barratt, Shull et al and Dechaux et al. )
Ideally a 24 hour urine collection and a mid-point serum creatinine
should be obtained. This method is the most accurate clinical
measure of creatinine clearance.
The Schwartz method, like several other CRCL predictive models,
attempts to estimate (not calculate) the creatinine
clearance. It is important to remember that the result listed above
should be considered a rough estimate of the CRCL. Also, it is
assumed that the serum creatinine is at steady state. If the
patient's renal function is declining you must wait until steady
state occurs or you will overestimate the clearance. The opposite
occurs if the patient's renal function is improving.
Counahan R, Chantler C, Ghazali S, Kirkwood B, Rose F, Barratt TM.
Estimation of glomerular filtration rate from plasma creatinine
concentration in children. Arch Dis Child. 1976 Nov;51(11):875-8.
Schwartz GJ, Haycock GB, Edelmann CM Jr, Spitzer A: A simple
estimate of glomerular filtration rate in children derived from body
length and plasma creatinine. Pediatrics 58:259-263, 1976.
Shull BC, Haughey D, Koup JR, Baliah T, Li PK. A useful method for
predicting creatinine clearance in children. Clin Chem. 1978
Jul;24(7):1167-9.
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