Evidence Check
6 min read
查核：「抽血肌酸酐正常，腎臟就沒問題」是真的嗎？
不成立。單一血清肌酸酐「在實驗室正常範圍內」並不能排除慢性腎臟病，評估需以肌酸酐帶入 eGFR 公式，並結合尿檢及臨床情況；在肌肉量少、高齡、女性、慢性病患者等族群中特別容易低估腎損傷。
eGFR Calculator · CKD-EPI 2021 · KDIGO 2024
eGFR Calculator (CKD-EPI 2021)
Enter age, sex and serum creatinine to estimate glomerular filtration rate with the race-free 2021 CKD-EPI equation, mapped to KDIGO 2024 G stages.
What this tool does
Estimate eGFR and G stage from one blood creatinine value.
What you need
Creatinine from your lab report (mg/dL or µmol/L), age and sex.
What the result means
An eGFR value with its stage explained; a single value is affected by muscle mass, hydration and drugs — watch the trend.
Estimated GFR
mL/min/1.73 m²
What this stage means
A single eGFR cannot diagnose CKD. CKD is defined as abnormal kidney function or structure persisting for more than 3 months; acute illness, dehydration, recent heavy exercise or a large meat meal all transiently affect creatinine.
Enter the values above
- G1 Normal or high (≥90)
- G2 Mildly decreased (60–89)
- G3a Mildly to moderately decreased (45–59)
- G3b Moderately to severely decreased (30–44)
- G4 Severely decreased (15–29)
- G5 Kidney failure (<15)
Privacy: all calculations run on your device; no values are sent to a server or third party. Log-type tools store data only in your browser (localStorage); clearing browsing data removes it.
This is not a diagnosis. It maps the numbers you entered onto published guideline categories; a real assessment needs a clinician, your history, repeat testing and other investigations.
Scope and limitations
- Adults ≥18 only; children require the Schwartz equation.
- Assumes creatinine is at steady state; inaccurate in acute kidney injury, during hospitalisation or dehydration.
- Larger error at extremes of muscle mass (bodybuilders, amputees, sarcopenia, bed-bound, vegetarians); ask your doctor about cystatin C and the CKD-EPI 2021 cr-cys equation.
- The 2021 equation removed the race coefficient; validation in Asian populations is comparatively limited, and Taiwan/Japan have local equations (e.g. JSN eGFRcreat) that may differ slightly.
- Result rounded to a whole number; precision above 60 is lower, and guidelines accept reporting as ">60" or the actual value.
Formula & cut-off sources
- KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD. Kidney Int 2024;105(4S):S117–S314
- Inker LA, et al. New Creatinine- and Cystatin C–Based Equations to Estimate GFR without Race. N Engl J Med 2021;385:1737-1749
- National Kidney Foundation — eGFR Calculator (CKD-EPI 2021)
To discuss with your doctor
- Which stage am I in? Should it be repeated to confirm?
- Do I need a urine albumin (UACR) test?
- Which of my medicines need adjusting for kidney function?
- Would a cystatin C test be useful for me?
Next step
After this result, people usually continue with:
Further reading
Evidence Check
5 min read
查核：「每天多喝水（3 公升以上）能沖洗腎臟、保護腎功能」是真的嗎？
結論：部分正確。適度補充水分對健康重要，但現有研究顯示，刻意把每天喝水量大幅拉高，並沒有明確證據可以「沖洗腎臟」或明顯減緩慢性腎臟病惡化[1][2][3]。
Chronic Kidney Disease
6 min read
Understanding eGFR and Serum Creatinine: Formulas, Limitations, and Causes of Variability
Explains commonly used eGFR formulas (including CKD‑EPI 2021), how serum creatinine is affected by muscle mass and diet, the role of cystatin C, and key points for interpreting single…
