Hepatology
MELD-Na Score
MELD adjusted for serum sodium.
Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.
Background
The MELD-Na score estimates short-term mortality in chronic liver disease by adding serum sodium to the original Model for End-stage Liver Disease (MELD). MELD itself is calculated from serum bilirubin, INR and creatinine, and is widely used to prioritise patients on liver-transplant waiting lists. Hyponatraemia is an independent marker of advanced liver disease and portal hypertension, so incorporating sodium improves the prediction of death beyond MELD alone. Bilirubin and creatinine are entered in mg/dL and sodium in mmol/L, with sodium bounded to the 125–137 range.
Interpreting the result
A higher MELD-Na indicates greater severity and shorter expected survival. Broadly, scores under 10 reflect lower severity, 10–19 moderate severity, and 20 or above high severity with a steeply rising mortality. The sodium adjustment is applied when the underlying MELD is above 11, so it matters most in more advanced disease. The score is a prognostic and allocation tool, not a treatment plan in itself.
Worked example
A patient with cirrhosis has a bilirubin of 4 mg/dL, INR 1.8, creatinine 1.5 mg/dL and sodium 128 mmol/L. The bilirubin, INR and creatinine give a MELD in the high teens, and the low sodium pushes the MELD-Na above 20 — a high-severity result that warrants specialist hepatology review and transplant discussion.
Critical actions
Bilirubin and creatinine in mg/dL; sodium bounded to 125–137. The Na adjustment applies when MELD >11.
Pearls / pitfalls
- Use the correct units — bilirubin and creatinine in mg/dL, sodium in mmol/L — as entering SI units unconverted will give a badly wrong score.
- Sodium is capped at 125–137 mmol/L, so very low readings are floored at 125 to avoid over-weighting.
- It predicts mortality, not transplant suitability or candidacy, which depend on many other factors.
- Renal replacement therapy in the preceding period affects how creatinine is handled in some scoring conventions, so follow local allocation rules.
Evidence & validation
The prognostic value of adding sodium was shown by Kim and colleagues in the New England Journal of Medicine in 2008, and MELD-Na was subsequently adopted by transplant allocation systems including UNOS for prioritising candidates.
Frequently asked questions
How does MELD-Na differ from MELD?
MELD-Na adds serum sodium to the bilirubin, INR and creatinine used in MELD. Because hyponatraemia independently predicts death in cirrhosis, the sodium term improves mortality prediction, particularly in more advanced disease.
When does the sodium adjustment apply?
The sodium correction is applied when the underlying MELD is above 11. At lower MELD values the adjustment has little effect, so MELD-Na and MELD are similar.
Why is sodium bounded to 125–137?
Values are capped to this range to prevent extreme readings from over-influencing the score. Sodium below 125 is treated as 125 and above 137 as 137.
What units should I use?
Bilirubin and creatinine are entered in mg/dL and sodium in mmol/L. Using SI units (for example µmol/L for bilirubin) without converting will produce an incorrect score.
Does a high MELD-Na mean a patient will get a transplant?
No. It estimates mortality and helps prioritise waiting lists, but transplant candidacy depends on many additional clinical, surgical and social factors assessed by a specialist team.
References
- Kim WR, Biggins SW, Kremers WK, et al. Hyponatremia and mortality among patients on the liver-transplant waiting list. N Engl J Med. 2008;359(10):1018–1026.
- European Association for the Study of the Liver (EASL). Clinical Practice Guidelines on liver transplantation.
Related calculators
Need a calculator we don't have — or a custom tool?
We build evidence-led clinical calculators, dashboards and reference tools for teams.