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MELD Score Calculator

Calculate the Model for End-Stage Liver Disease (MELD) and MELD-Na scores. Enter serum lab values to estimate liver disease severity and 3-month mortality risk.

Quick Answer

MELD = 10 x (0.957 x ln(Creatinine) + 0.378 x ln(Bilirubin) + 1.120 x ln(INR) + 0.643), rounded to the nearest integer. MELD-Na adjusts for serum sodium. Scores range from 6-40; higher scores indicate more severe liver disease. MELD is used by UNOS to prioritize liver transplant allocation in the United States.

Serum Bilirubin

mg/dL

Normal range: 0.1 - 1.2 mg/dL

Serum Creatinine

mg/dL

Normal range: 0.7 - 1.3 mg/dL. Capped at 4.0 for MELD.

INR (International Normalized Ratio)

Normal range: 0.8 - 1.2

Serum Sodium

mEq/L

Normal range: 136 - 145 mEq/L. Clamped to 125-140 for MELD-Na.

Your Results

MELD Score

MELD-Na Score

3-Month Mortality

~1.9%

Disease Severity

Low Severity (MELD-Na: 7)

MELD Score and 3-Month Mortality

MELD 6 - 93-month mortality~1.9%Current

MELD 10 - 193-month mortality~6.0%

MELD 20 - 293-month mortality~19.6%

MELD 30 - 393-month mortality~52.6%

MELD 403-month mortality~71.3%

Transplant Allocation Context

UNOS uses MELD-Na scores to prioritize liver transplant candidates. Higher scores indicate greater urgency. As of January 2016, MELD-Na replaced the original MELD score for organ allocation purposes. Patients with a MELD-Na score of 15 or higher are generally considered candidates for transplant listing. Exception points may be granted for conditions like hepatocellular carcinoma that are not fully captured by lab values alone.

Medical Disclaimer: This MELD Score Calculator is intended for educational and informational purposes only. It is not a substitute for professional medical evaluation, diagnosis, or treatment. MELD scores should be calculated using laboratory-certified values and interpreted by qualified hepatologists or transplant physicians. Organ allocation decisions involve complex clinical factors beyond the MELD score alone. Always consult your healthcare provider for medical decisions.

About This Tool

The Model for End-Stage Liver Disease (MELD) score is a numerical scale used to assess the severity of chronic liver disease and predict short-term mortality in patients with end-stage liver disease. Originally developed in 2001 by researchers at the Mayo Clinic to predict survival after transjugular intrahepatic portosystemic shunt (TIPS) procedures, the MELD score was adopted by the United Network for Organ Sharing (UNOS) in February 2002 to prioritize liver transplant candidates. This adoption replaced the previous Child-Turcotte-Pugh (CTP) classification system, which relied on more subjective clinical assessments.

The MELD Formula

The original MELD score uses three objective laboratory values: serum bilirubin (measuring the liver's ability to excrete bile), serum creatinine (measuring kidney function, which is often impaired in advanced liver disease), and the International Normalized Ratio or INR (measuring the liver's ability to produce clotting factors). The formula is: MELD = 10 x (0.957 x ln(Creatinine) + 0.378 x ln(Bilirubin) + 1.120 x ln(INR) + 0.643). All laboratory values below 1.0 are set to 1.0 to prevent negative scores from logarithmic calculations, and creatinine is capped at 4.0 mg/dL. The resulting score ranges from 6 to 40, with higher scores indicating more severe disease and greater urgency for transplantation.

MELD-Na: Incorporating Sodium

In January 2016, UNOS adopted the MELD-Na score for liver transplant allocation, recognizing that serum sodium is an independent predictor of mortality in cirrhotic patients. Hyponatremia (low sodium) is common in patients with advanced cirrhosis due to impaired free water excretion and is associated with complications including hepatic encephalopathy, hepatorenal syndrome, and increased post-transplant mortality. The MELD-Na formula adjusts the original MELD score based on serum sodium levels, with sodium values clamped between 125 and 140 mEq/L. Studies have shown that MELD-Na provides better prediction of waitlist mortality than the original MELD score, particularly for patients with moderate liver disease scores.

Clinical Applications

Beyond transplant allocation, the MELD score has proven useful in several other clinical contexts. It helps predict outcomes for patients hospitalized with cirrhosis complications such as variceal bleeding, spontaneous bacterial peritonitis, and hepatorenal syndrome. Surgeons use MELD scores to estimate perioperative mortality in cirrhotic patients undergoing non-hepatic surgery. A MELD score above 15 is associated with significantly increased surgical risk, and scores above 20 generally contraindicate elective procedures. The score is also used to guide the timing of referral to transplant centers, with most guidelines recommending evaluation when the MELD score reaches 15 or higher.

Limitations of the MELD Score

Despite its widespread use, the MELD score has recognized limitations. It does not capture the severity of certain conditions well, including hepatocellular carcinoma, hepatopulmonary syndrome, and polycystic liver disease, which is why UNOS grants exception points for these conditions. The score can be influenced by factors unrelated to liver function; for example, creatinine levels may be elevated due to intrinsic kidney disease rather than hepatorenal syndrome. Laboratory variability between different hospitals and assay methods can also affect scores, which is why UNOS requires that labs used for MELD calculation be performed within specific timeframes. Patients on dialysis are assigned a creatinine of 4.0 mg/dL regardless of their actual value.

MELD 3.0: The Future of Liver Allocation

MELD 3.0 was approved by UNOS in 2023 and represents the latest evolution of the scoring system. It incorporates sex as a variable (addressing the documented disparity in transplant access for women), adds serum albumin as a predictor, and replaces creatinine with a combined measure of kidney function. MELD 3.0 has demonstrated improved prediction of waitlist mortality compared to MELD-Na across all demographic groups. This calculator currently uses the MELD-Na formula, which remains the most commonly referenced version in clinical practice and medical education.

Frequently Asked Questions

What is a MELD score and what does it measure?

The MELD (Model for End-Stage Liver Disease) score is a number from 6 to 40 that measures how severe a person's liver disease is based on laboratory values. It uses serum bilirubin, creatinine, and INR to predict 3-month mortality risk. Higher scores indicate more severe disease. It is used by UNOS to prioritize patients on the liver transplant waiting list.

What is the difference between MELD and MELD-Na?

MELD-Na is an updated version of the original MELD score that incorporates serum sodium levels. Low sodium (hyponatremia) is common in advanced cirrhosis and independently predicts mortality. MELD-Na provides more accurate mortality prediction than the original MELD, particularly for patients with moderate liver disease. MELD-Na has been used for transplant allocation since January 2016.

What MELD score qualifies for a liver transplant?

There is no single MELD score threshold that 'qualifies' someone for transplant. Generally, patients with a MELD-Na of 15 or higher are considered for transplant listing. However, actual transplant depends on organ availability, blood type, body size, waiting time, and geographic factors. Exception points may raise the effective MELD for conditions not captured by lab values.

Why are lab values clamped in the MELD formula?

Lab values are clamped to prevent mathematical artifacts and ensure clinical relevance. Values below 1.0 are set to 1.0 because the natural logarithm of numbers less than 1 is negative, which would inappropriately lower the score. Creatinine is capped at 4.0 mg/dL because extremely high values (as seen in dialysis patients) would disproportionately inflate the score. Sodium is bounded between 125-140 mEq/L based on the range studied in the MELD-Na derivation cohort.

How often should MELD be recalculated?

UNOS requires MELD recalculation at specific intervals based on the score: every 12 months for scores below 11, every 3 months for 11-18, every month for 19-24, and every 7 days for scores of 25 or higher. More frequent recalculation is required for higher scores because these patients are sicker and their condition can change rapidly.

Can the MELD score decrease over time?

Yes. MELD scores can improve if the underlying cause of liver disease is treated. For example, patients with alcoholic hepatitis who achieve sobriety, or those with hepatitis B/C who respond to antiviral therapy, may see significant improvement in their lab values and MELD score. However, in many cases of advanced cirrhosis, the MELD score tends to trend upward over time as liver function progressively deteriorates.

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