MELD-Na Score Calculator

MELD-Na Score Calculator for Gastroenterology. Higher scores mean higher short-term mortality and greater transplant priority. As rough anchors for 3-month waitlist mortality: a MELD-Na around 9 or below carries roughly 2–4% mortality; the high teens correspond to about 6–10%; the high 20s to roughly 20%; and scores of 35–40 exceed 50–70%. In the original Biggins cohort, MELD-Na values of 20, 30, and 40 mapped to about 6%, 16%, and 37% 6-month mortality. The actionable point is that adding sodium reclassifies patients upward: in the NEJM validation, sodium-adjusted scoring would have raised priority in a subset of candidates who died on the list, so a hyponatremic patient with a modest base MELD should not be regarded as low-risk.

How this calculator works

MELD-Na augments the standard MELD score with serum sodium to sharpen short-term mortality prediction in cirrhosis. The classic MELD is first computed from bilirubin, INR, and creatinine (each floored at 1.0; creatinine capped at 4.0 and set to 4.0 if on dialysis twice in the prior week), then rounded to an integer between 6 and 40. When MELD exceeds 11, the UNOS/OPTN implementation adds a sodium correction: MELD-Na = MELD + 1.32 × (137 − Na) − [0.033 × MELD × (137 − Na)], with sodium bounded to 125–137 mmol/L. Lower sodium raises the score, and the correction has greatest weight at lower MELD values where hyponatremia carries the most independent prognostic signal.

When to use this calculator

Use MELD-Na to stratify 90-day waitlist mortality in adults (age ≥12) with chronic liver disease and to prioritize deceased-donor liver allocation, the role for which UNOS/OPTN adopted it in January 2016. It is most useful in decompensated cirrhosis with ascites or dilutional hyponatremia, where sodium adds discrimination the base MELD misses. Do not use it in acute liver failure, for pediatric candidates (who use PELD), or to justify exception points such as hepatocellular carcinoma. Interpret cautiously when sodium has been acutely corrected with hypertonic saline or when recent transfusion/anticoagulation distorts INR.

Inputs used

  • Bilirubin
  • INR
  • Creatinine
  • Sodium
  • Dialysis status when applicable

Clinical interpretation

Higher scores mean higher short-term mortality and greater transplant priority. As rough anchors for 3-month waitlist mortality: a MELD-Na around 9 or below carries roughly 2–4% mortality; the high teens correspond to about 6–10%; the high 20s to roughly 20%; and scores of 35–40 exceed 50–70%. In the original Biggins cohort, MELD-Na values of 20, 30, and 40 mapped to about 6%, 16%, and 37% 6-month mortality. The actionable point is that adding sodium reclassifies patients upward: in the NEJM validation, sodium-adjusted scoring would have raised priority in a subset of candidates who died on the list, so a hyponatremic patient with a modest base MELD should not be regarded as low-risk.

Worked example

A woman with alcohol-related cirrhosis has bilirubin 6 mg/dL, INR 1.9, creatinine 1.4 mg/dL, and sodium 128 mmol/L. Her base MELD computes to roughly 22. Because MELD exceeds 11, the sodium term applies: MELD-Na = 22 + 1.32 × (137 − 128) − 0.033 × 22 × (137 − 128) = 22 + 11.9 − 6.5 ≈ 27. Hyponatremia has moved her from a MELD of 22 to a MELD-Na of 27, meaningfully raising her estimated 90-day waitlist mortality and her allocation priority.

Limitations and safety notes

The sodium benefit is concentrated in patients with lower MELD scores and near-negligible at high MELD, so it changes little for the sickest candidates. Because it hinges on a single sodium value, it is vulnerable to spurious hyponatremia (hyperglycemia, hyperlipidemia) and to rapid iatrogenic correction, and it does not capture sarcopenia, frailty, refractory ascites, or hepatic encephalopathy that also drive mortality. Creatinine-based components underestimate severity in women and in patients with muscle wasting, and MELD-Na was not designed to predict post-transplant outcomes. Note the current U.S. allocation standard has since moved to MELD 3.0, which incorporates sex and albumin alongside sodium.

Frequently asked questions

How is MELD-Na different from the standard MELD score?

Standard MELD uses only bilirubin, INR, and creatinine. MELD-Na adds serum sodium, penalizing hyponatremia, because low sodium independently predicts waitlist death even after accounting for the other three variables. The sodium term is applied only when the base MELD is above 11.

Why does the sodium correction matter more at lower MELD scores?

In the derivation data there was a significant interaction between MELD and sodium: hyponatremia added the most prognostic information in patients whose base MELD was relatively low. At very high MELD scores, the underlying disease severity already dominates, so sodium contributes little additional discrimination.

What sodium range is used in the calculation?

Sodium is bounded to 125–137 mmol/L in the UNOS implementation. Values below 125 are treated as 125 and values above 137 as 137, which caps how much a single extreme sodium can move the score.

Is MELD-Na still the allocation standard?

MELD-Na was the U.S. deceased-donor liver allocation score from January 2016. In 2023 UNOS/OPTN transitioned to MELD 3.0, which retains sodium but also adds serum albumin and a sex adjustment to reduce the disadvantage historically faced by women.

Can I use MELD-Na in acute liver failure?

No. MELD and MELD-Na were derived and validated in chronic end-stage liver disease. Acute liver failure has different prognostic drivers and is assessed with tools such as the King's College Criteria rather than MELD-Na.

References

  • Kim WR, Biggins SW, Kremers WK, Wiesner RH, Kamath PS, Benson JT, Edwards E, Therneau TM. Hyponatremia and mortality among patients on the liver-transplant waiting list. N Engl J Med. 2008;359(10):1018-26. PMID: 18768945.
  • Biggins SW, Kim WR, Terrault NA, Saab S, Balan V, Schiano T, Benson J, Therneau T, Kremers W, Wiesner R, Kamath P, Klintmalm G. Evidence-based incorporation of serum sodium concentration into MELD. Gastroenterology. 2006;130(6):1652-60. PMID: 16697729.
  • Organ Procurement and Transplantation Network (OPTN). Policy 9: Allocation of Livers and Liver-Intestines (MELD-Na implementation, adopted January 2016). 2016.

Editorial review and citation methodology

Reviewed by the Quick Medical Calculator Editorial Team. Last reviewed: March 5, 2026. The review checks calculator inputs, intended population, interpretation, limitations, and source alignment.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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