Calculation of eGFR creatinine
eGFR creatinine is a calculation used to estimate the filtration capacity of the kidneys based on creatinine in the blood. The test is the most widely used method in healthcare to assess kidney function in adults. The calculation provides a measure of how effectively the kidneys filter the blood and is used both in screening and in the follow-up of suspected or known kidney damage.
How is the calculation of eGFR (crea) performed
When a sample is taken, creatinine is measured in the blood. Based on this value, eGFR is calculated using an established formula (usually CKD-EPI) that takes age and gender into account. The result is given as milliliters per minute per 1.73 m² of body surface area (mL/min/1.73 m²) and is used as a standardized measure of kidney function.
When is eGFR creatinine a suitable choice?
- As an initial assessment of kidney function.
- When checking kidney values in connection with a health examination.
- When following up on known risk factors such as high blood pressure or diabetes.
- Before or during treatment with medications that affect the kidneys.
How are the results of eGFR creatinine interpreted?
A higher eGFR value generally corresponds to better kidney function, while lower values may indicate impaired kidney function. Elevated or lowered levels always need to be interpreted in relation to the individual's age, general condition and other test results.
Limitations of eGFR creatinine
Since the calculation is based on creatinine, the result can be affected by factors such as muscle mass, diet, fluid balance and certain medications or dietary supplements. In people with abnormal muscle mass or in case of uncertainty about the result, it may be valuable to supplement with eGFR based on cystatin C.
Important before taking the sample
- Avoid heavy physical exertion before taking the sample.
- Avoid large meat intake the day before the test.
- Make sure to be well hydrated.
In case of deviation, the result should always be followed up and assessed by a doctor.
