The eGFR Calculator (estimated Glomerular Filtration Rate)
Download this calculator to your personal laptop, phone or PDA. If you are a health professional, use this eGFR calculator in conjunction with our eGFR Summary Card - CKD Management in General Practice.
Macromedia Flash Windows version, or Mac version, or PalmOS version.
Mobile phones and other devices supporting Java* - **Java ZIP file ***Java JAR and JAD
*Calculator layout may vary depending on implementation of Java on mobile device
**Unzip and copy files to mobile device
***Download to mobile device. You may need both files and to "right-click" and select 'Save as' for JAD file
eGFR stands for estimated Glomerular Filtration Rate
If a doctor orders a blood test to learn more about your kidney function, an eGFR result is usually provided automatically by the pathology laboratory along with blood concentration and creatinine results. The glomerular filtration rate measures how well kidneys filter the waste products and toxins from a patient's blood and is the best indicator of kidney function. It helps determine if there is any damage. By combining the result of blood creatinine level with the patient's age and gender, kidney function is measured using a special formula to provide an 'estimated Glomerular Filtration Rate' or eGFR
The higher the filtration rate, the better the kidneys are working.
Normal filtration rate is about 100 millilitres per minute, or 100 mL/min.
What does an eGFR result look like?
The eGFR result is reported in millilitres per minutes and is shown as mL/min/1.732. A normal GFR is greater than 90 mL/min/1.73m2. If an eGFR result is less than 90, the actual value will be shown. For example, a result of 67 - would be shown as 67 mL/mm/1.72.
Results of 90 or greater are shown as: eGFR ≥ 90 mL/min/1.73m2
eGFR Clinical Tools
Clinical situations where the eGFR results may be unreliable and/or misleading include:
- Clinical situations where eGFR results may be unreliable and/or misleading include:
- Acute changes in kidney function (e.g. acute kidney failure)
- Dialysis-dependent patients
- Exceptional dietary intake (e.g. vegetarian diet, high protein diet, recent consumption of cooked meat, creatine supplements)
- Extremes of body size
- Diseases of skeletal muscle, paraplegia, or amputees (may underestimate) or high muscle mass (may overestimate)
- Children under the age of 18 years
- Severe liver disease present
Use of eGFR in different ethnic populations
The original MDRD formula contains a factor to be applied to African-American subjects raising the possibility that other variations in the formula may be required for optimal performance in different racial groups. Pending publication of validation studies it is recommended Australasian laboratories continue to automatically report eGFR in Aboriginal and Torres Strait Islander peoples and other ethnic groups. For critical dose drugs, particularly in the hospital setting, it remains important to adhere to the published recommendations.
eGFR and drug dosing
Where an eGFR result (using MDRD) is presented it is clinically appropriate to use this to assist drug dosing decision making. Published recommendations usually involve the use of the Cockcroft-Gault equation to estimate eGFR, or to measure creatinine clearance in order to amend dosing for renal function. Cockcroft-Gault GFR formula may still be used for drug dosing calculation.
Ms Breonny Robson | KCAT Project Manager | GPO Box 9993 Adelaide SA 5001
Chronic Kidney Disease (CKD) Management in General Practice
The CKD Management in General Practice booklet (and supporting Publication reference list) is a valued and popular education booklet written for health professionals involved in the care and treatment of people with kidney disease.
Booklet formally endorsed by the RACGP, the ANZSN and Kidney Health Australia. It is published to provide a comprehensive summary of current guidelines and recommendations from various sources. It is accompanied by a laminated Summary Card for CKD Management in General Practice (see example)
|
eGFR
mL/min/1.73m2
|
Description
|
Clinical Action Plan
|
|
≥ 90
|
Stage 1 CKD
- kidney damage* with normal kidney function
|
Further investigation for CKD may be indicated in those at increased risk**:
- blood pressure
- assessment of proteinuria
- urinalysis
Cardiovascular risk reduction:
- blood pressure
- lipids
- blood glucose
- lifestyle modification (smoking, weight, physical activity, nutrition, alcohol)
|
|
60-89
|
Stage 2 CKD
- kidney damage* with mild kidney function
|
|
30 - 59
|
Stage 3 CKD
- moderate kidney function
|
As above, plus:
- monitor eGFR 3 monthly
- avoid nephrotoxic drugs
- prescribe antiproteinuric drugs (ACE inhibitors and/or ARBs) if appropriate
- address common complications
- ensure drug dosages appropriate for level of kidney function
Consider indications for referral to a nephrologist
|
|
15 - 29
|
Stage 4 CKD
- severe kidney function
|
As above + referral to nephrologist is usually indicated for physical and psychosocial preparation for renal replacement therapy (dialysis, pre-emptive transplantation, transplantation) or conservative medical management
|
|
< 15
|
Stage 5 CKD
- end-stage kidney disease
|
As above + referral to a nephrologist
|
*imaging or biopsy abnormalities, or proteinuria/haematuria
**hypertension, diabetes, smoker, age >50 yrs, obesity, family history of kidney disease, Indigenous Australian
Kidney Community News Bulletin - brings you clinical and non clinical information from the kidney world and updates on our professional programs. Subscribe to community@kidney.org.au providing your contact details.
|