Estimerat GFR från kreatinin och cystatin C med olika formler — för vuxna och barn, med CKD-stadium.
eGFR · medel av valda—mL/min/1,73m²
Njursviktskategori—Fyll i värden
Kombinerat
EKFC—
FAS—
r-LMR—
CKD-EPI—
mL/min/1,73m²
Patient
år
µmol/L
mg/L
Kreatinin
EKFC—mL/min/1,73m²
FAS—mL/min/1,73m²
r-LMR—mL/min/1,73m²
CKD-EPI—mL/min/1,73m²
LMR18—mL/min/1,73m²
MDRD—mL/min/1,73m²
BIS (≥70 år)—mL/min/1,73m²
Cystatin C
EKFC—mL/min/1,73m²
FAS—mL/min/1,73m²
r-LMR—mL/min/1,73m²
CKD-EPI—mL/min/1,73m²
CAPA—mL/min/1,73m²
Referenser
eGFR-ekvationer (vuxna)
[1] Pottel H, Björk J, Bökenkamp A, et al. (2021). Development and validation of a modified full age spectrum creatinine-based equation to estimate glomerular filtration rate (EKFC). Annals of Internal Medicine, 174(2), 183–191. PMID: 33166224. DOI ↗
[2] Pottel H, Björk J, Rule AD, et al. (2023). Cystatin C–based equation to estimate GFR without the inclusion of race and sex (EKFC). New England Journal of Medicine, 388(4), 333–343. DOI ↗
[3] Pottel H, Delanaye P, Schaeffner E, et al. (2017). Estimating glomerular filtration rate for the full age spectrum from serum creatinine and cystatin C (FAS). Nephrology Dialysis Transplantation, 32(3), 497–507. DOI ↗
[4] Nyman U, Björk J, Leion F, et al. (2024). The revised Lund-Malmö creatinine-based GFR estimating equation (r-LMR). Clinical Chemistry and Laboratory Medicine, 62(3), 421–427. PMID: 37768854. DOI ↗
[5] Björk J, Nyman U, Delanaye P, et al. (2024). Extending the revised Lund-Malmö equation to cystatin C (r-LMRcys). Scandinavian Journal of Clinical and Laboratory Investigation, 84(7–8), 577–583. DOI ↗
[6] Inker LA, Eneanya ND, Coresh J, et al. (2021). New creatinine- and cystatin C–based equations to estimate GFR without race (CKD-EPI 2021). New England Journal of Medicine, 385(19), 1737–1749. DOI ↗
[7] Björk J, Grubb A, Sterner G, Nyman U. (2011). Revised equations for estimating glomerular filtration rate based on the Lund-Malmö Study cohort (LMR). Scandinavian Journal of Clinical and Laboratory Investigation, 71(3), 232–239. PMID: 21391777. DOI ↗
[8] Grubb A, Horio M, Hansson LO, et al. (2014). Generation of a new cystatin C–based estimating equation for GFR by use of 7 assays standardized to international calibrators (CAPA). Clinical Chemistry, 60(7), 974–986. DOI ↗
[9] Levey AS, Coresh J, Greene T, et al. (2006). Using standardized serum creatinine values in the Modification of Diet in Renal Disease study equation (IDMS-MDRD). Annals of Internal Medicine, 145(4), 247–254. DOI ↗
[10] Schaeffner ES, Ebert N, Delanaye P, et al. (2012). Two novel equations to estimate kidney function in persons aged 70 years or older (BIS1/BIS2). Annals of Internal Medicine, 157(7), 471–481. DOI ↗
Barnekvationer
[11] Schwartz GJ, Muñoz A, Schneider MF, et al. (2009). New equations to estimate GFR in children with CKD (bedside Schwartz). Journal of the American Society of Nephrology, 20(3), 629–637. DOI ↗
[12] Pierce CB, Muñoz A, Ng DK, et al. (2021). Age- and sex-dependent clinical equations to estimate GFR in children and young adults (CKiD U25). Kidney International, 99(4), 948–956. PMID: 33301749. DOI ↗
[13] Zappitelli M, Parvex P, Joseph L, et al. (2006). Derivation and validation of cystatin C–based prediction equations for GFR in children. American Journal of Kidney Diseases, 48(2), 221–230. DOI ↗
[14] Björk J, Nyman U, Delanaye P, et al. (2020). A novel method for creatinine adjustment makes the revised Lund-Malmö GFR estimating equation applicable in children. Scandinavian Journal of Clinical and Laboratory Investigation, 80(6), 456–463. PMID: 32628043. DOI ↗
Q-värden och stadieindelning
[15] Delanaye P, Pottel H, Schaeffner E, et al. (2024). The EKFC equation: Q-value polynomials and validation. Clinical Kidney Journal, 17(9), sfae261. DOI ↗
[16] Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. (2013). KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International Supplements, 3(1), 1–150. DOI ↗
Metodik och formler
Kreatinin anges i µmol/L; Skr,mgdl = µmol/L ÷ 88,4. Cystatin C i mg/L.
Ålder i år. Alla resultat i mL/min/1,73 m².
Q-värden [15]: kreatinin — åldersberoende Q-polynom (2–25 år), fast Q=0.9 (man) / 0.7 (kvinna) mg/dL först >25 år; cystatin C Q=0.83 (könsneutral), könsspecifikt 0.86 (M) / 0.79 (K), med +0.005(a˚lder−50) vid ålder ≥ 50. Ålderstermen ka˚lder saknades i tidigare version och är nu tillagd.
Gemensam form för båda markörerna via S/Q. Kreatinin: Q=80 (M) / 62 (K) µmol/L. Cystatin C: könsneutralt Q som EKFC. Detta är den förenklade, könsneutrala r-LMR-formen (Björk 2024) där de tidigare könsspecifika koefficienterna (Nyman 2024) slagits samman.
Skr i mg/dL. Den kombinerade ekvationens konstanter är korrigerade mot Inker 2021. Cystatin C-only-ekvationen är 2012 års form (oförändrad i 2021-uppdateringen).
Originalkohort 1–18 år (validerad mot iotalamat-GFR); använd med försiktighet utanför liknande population. Valbara modifierare i verktyget: njurtransplantation (cystatin ×1,2; kombinerat ×1,165) och spina bifida (kombinerat × Skr0.925/40.45).