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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Creatinine

Test Code(s): CRET

CPT Code(s): 82565

Test Description: Test Component:

Creatinine and estimated Glomerular Filtration Rate (e-GFR)- calculated for adult outpatients

Included In: Basic Metabolic Panel, Comprehensive Metabolic Panel, and Creatinine Clearance Package

Methodology: IDMS-traceable

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: 1 hour.
Routine: 4 hours.

Specimen Requirements

Specimen: Blood

Collection Container: Preferred: Green cap with yellow ring (PST)
Also Acceptable: Green top, Red cap with yellow ring (SST), Red top

Collection Volume: Preferred: 1 mL
Pediatrics: 0.4 mL

Sample Analyzed: Plasma or serum

Volume Required: Preferred: 0.5 mL
Pediatrics: 0.2 mL

Specimen Processing: Centrifuge.  If a complete barrier has not formed, transfer cell-free plasma/serum to plastic vial.  Refrigerate.

Specimen Transport: Transport specimen to the laboratory. Transport with coolant pack if coming from outreach location.

Stability: Refrigerated: 4 days
Frozen: Indefinitely


Reference Interval:




 0 days-1 month  0.30-0.90  0.30-0.90
 2 months-2 years  0.15-0.40  0.15-0.40
 3 years-6 years  0.25-0.50  0.25-0.50
 7 years-10 years  0.30-0.65  0.30-0.65
 11 years-14 years  0.40-0.80  0.40-0.80
 15 years and up  0.70-1.20  0.55-1.05


 18 years and up:  60-120 mL/min/1.73 sqm
 e-GFR Interpretive Statement:
   Chronic kidney disease:  e-GFR < 60 mL/min/1.73 sqm
   Kidney failure:  e-GFR < 15 mL/min/1.73 sqm


 * For African-Americans multiply reported e-GFR result by 1.159.


Additional Information:

Estimated Glomerular Filtration Rate calculation uses the CKD-EPI National Kidney Foundation calculation for IDMS creatinine methods. See the following website for this calculation:

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