Test Center

My Recent Searches

  • No Recent Search.

My Tests Viewed

  • No Test Viewed.

Creatinine-based Estimated Glomerular Filtration Rate (eGFR)

Creatinine-based Estimated Glomerular Filtration Rate (eGFR)

Test Summary

Creatinine-based Estimated Glomerular Filtration Rate (eGFR)

  

Clinical Use

  • Detect chronic kidney disease (CKD) in adults

  • Monitor CKD therapy and/or progression in adults

Clinical Background

More than 31 million people in the United States are currently affected by CKD, and the prevalence of ensuing kidney failure is rising.1 Since evidence has shown that treatment at earlier stages is generally effective in preventing or delaying adverse outcomes, monitoring patients with and at risk of CKD becomes critically important for decreasing morbidity and mortality.

The Kidney Disease Improving Global Outcomes (KDIGO) guideline defines CKD by the presence of glomerular filtration rate (GFR) <60 mL/min/1.73m2 for >3 months and/or evidence of kidney damage (eg, structural abnormalities, histologic abnormalities, albuminuria, urinary sediment abnormalities, renal tubular disorders, and/or history of kidney transplantation) for >3months.2 Thus, monitoring should include tests for GFR, albuminuria, and urine sediment.

GFR has traditionally been estimated using the 24-hour creatinine clearance; however, a calculation of estimated glomerular filtration rate (eGFR) is now recommended by the National Institutes of Health (NIH) and the National Kidney Foundation. eGFR, based on serum creatinine and/or cystatin C, is a simpler and generally more reliable test.

Quest Diagnostics offers a variety of tests that include creatinine and eGFR calculation. These are summarized in Table 1.

Table 1. Quest Diagnostics Tests that Include eGFRa
Test Name Test Code

BUN/Creatinine Ratio

Includes BUN (294) and creatinine and calculated BUN/creatinine ratio and eGFR.

296

Creatinine

Includes serum creatinine and eGFR calculation.

375(X)

Creatinine Clearance

Includes serum (375[X]) and urine (8459[X]) creatinine and creatinine clearance and eGFR calculation.

7943(X)

Basic Metabolic Panel

Includes BUN/creatinine ratio (296), calcium (303), carbon dioxide (310), chloride (330), creatinine (375[X]), eGFR (calculated), glucose (483[X]), potassium (733), and sodium (836).

10165

Comprehensive Metabolic Panel

Includes albumin (223), albumin/globulin ratio (calculated), alkaline phosphatase (234[X]), ALT (823), AST (822), BUN/creatinine ratio (296), calcium (303), carbon dioxide (310), chloride (330), creatinine (375[X]), eGFR (calculated), globulin (calculated), glucose (483[X]), potassium (733), sodium (836), total bilirubin (287), and total protein (754).

10231

Diabetes, Advancing Chronic Kidney Disease Management Panel

Includes electrolyte panel (sodium [836], potassium [733], chloride [330], carbon dioxide [310]); hemoglobin (510[X]); intact PTH and calcium (8837); phosphate (phosphorus [718]); total 25-hydroxyvitamin D by immunoassay (17306); serum creatinine [375(X)]; urinary microalbumin with creatinine (6517); and eGFR (calculated).

91713(X)

Diabetes, Newly Diagnosed and Monitoring Panel

Includes glucose (483[X]); hemoglobin A1c (496); hepatic function panel (total protein [754], albumin [223], globulin [calculated], albumin/globulin ratio [calculated], total [287], direct [285], and indirect [calculated] bilirubin, alkaline phosphatase [234(X)], AST [822], and ALT [823]); lipid panel (total [334], HDL [608], and LDL [calculated] cholesterol; triglycerides [896] with reflex to direct LDL [8293]; cholesterol/HDL ratio [calculated]; and non-HDL [calculated]); serum creatinine [375(X)]; urinary microalbumin with creatinine (6517); and eGFR (calculated).

91712(X)

Renal Function Panel

Includes albumin (223), BUN/creatinine ratio (296), calcium (303), carbon dioxide (310), chloride (330), creatinine (375[X]), eGFR (calculated), glucose (483[X]), phosphate (as phosphorous), potassium (718), and sodium (836).

10314

ALT, alanine aminotransferase; AST, aspartate aminotransferase; BUN, blood urea nitrogen; eGFR, estimated glomerular filtration rate; HDL, high-density lipoprotein; LDL, low-density lipoprotein; PTH, parathyroid hormone.

a Panel components may be ordered separately.

Individuals Suitable for Testing

  • Adults aged 18 years and older who are at risk of or who have CKD

Individuals with diabetes, hypertension, autoimmune disease, systemic infections, and family history of kidney disease are some of those at increased risk.

This test is not suitable for people with unstable creatinine concentrations such as seen in patients hospitalized with acute illness, in pregnant women, and in those with serious comorbid conditions. Nor is this test suitable for people with extremes of muscle mass, ie, amputees, paraplegics, bodybuilders, patients with muscle-wasting disease, and patients with a neuromuscular disorder. This test is also not suitable for obese people3, patients suffering from malnutrition, those with a vegetarian or low-meat diet, and those taking creatine dietary supplements. Cystatin C (test code 10570 [X]) is a suitable alternative for these patients.

Method

The eGFR is calculated using isotope dilution mass spectrometry (IDMS)-traceable serum creatinine measurements and the patient’s age (18 years and older), gender, and race (African American vs non-African American) according to the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.4 Alternative calculations have been proposed for patients under age 18 years, but they are not offered by Quest at present. Quest test codes that include eGFR are listed in Table 1.

Interpretive Information

Table 2  provides interpretation of specific eGFR values. Creatinine measurements, and therefore eGFR calculations, are affected by very high or very low muscle mass, muscle injury, a diet very high in meat, hepatic cirrhosis, certain drugs, etc.

Table 2. Interpretation of eGFR Values2,a

eGFR (mL/min/1.73m2)

Interpretation

90b

Normal

60-89b Mild decrease
45-59 Mild to moderate decrease
30-44 Moderate to severe decrease
15-29 Severe decrease
<15 Kidney failure

eGFR, estimated glomerular filtration rate.

a

This table applies to creatinine-based and cystatin C-based eGFR.

b

The National Kidney Disease Education Program (NKDEP) recommends that actual values above 60 mL/min/1.73m2 be reported only as >60 due to variability near the upper limit of the reference range.5

References

  1. Centers for Disease Control and Prevention. Chronic kidney disease surveillance system—United States. website. http://www.cdc.gov/ckd. Accessed February 9, 2017.

  2. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Inter Suppl. 2013;3:1-150.

  3. Demirovic JA, Pai AB, Pai MP. Estimation of creatinine clearance in morbidly obese patients. Am J Health Syst Pharm. 2009;66:642-648.

  4. Levey AS, Stevens LA, Schmid CH, et al; CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration). A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009;150:604-612. Erratum in: Ann Intern Med. 2011;155:408.

  5. Myers GL, Miller WG, Coresh J, et al. Recommendations for improving serum creatinine measurement: a report from the Laboratory Working Group of the National Kidney Disease Education Program. Clin Chem. 2006;52:5-18.
     

Content reviewed 04/2017

 
top of page

* The tests listed by specialist are a select group of tests offered. For a complete list of Quest Diagnostics tests, please refer to our Directory of Services.