What is the MELD (Model for End‑Stage Liver Disease) score, how is it calculated, and what do its values indicate for transplant priority and short‑term prognosis?

MELD Score: Calculation, Interpretation, and Clinical Application

What is the MELD Score?

The MELD (Model for End-Stage Liver Disease) score is a validated, objective scoring system that predicts 3-month mortality in patients with end-stage liver disease and serves as the primary tool for prioritizing liver transplant allocation in the United States and most European countries. 1

The score was originally developed to assess short-term prognosis in patients undergoing transjugular intrahepatic portosystemic shunts (TIPS) but has since become the standard for transplant prioritization. 2, 3

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How is MELD Calculated?

The Formula

MELD uses three objective laboratory parameters in a logarithmic formula: 1, 2

MELD = 3.8 × ln(bilirubin mg/dL) + 11.2 × ln(INR) + 9.6 × ln(creatinine mg/dL) + 6.4 1

Key Components

• Serum bilirubin (mg/dL): Reflects hepatocellular synthetic function 1, 2
• INR (International Normalized Ratio): Measures coagulation function and hepatic synthetic capacity 1, 2
• Serum creatinine (mg/dL): Captures renal function, a critical prognostic marker in liver disease 1, 2
  • Maximum creatinine value capped at 4.0 mg/dL for patients on renal replacement therapy 1

The Resulting Score

• Range: 6 to 40 on a continuous scale 1, 2
• Correlation: Higher scores indicate higher short-term mortality risk 1, 3
  • MELD 6 = ~90% 3-month survival
  • MELD 40 = ~7% 3-month survival 2

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What Do MELD Values Indicate?

Transplant Priority Thresholds

MELD ≥15 is the established threshold for liver transplant listing, because patients with MELD ≤14 have better 1-year survival without transplantation than with it. 1, 2, 4

Mortality Risk Stratification

• MELD <15: Low risk; ~6% 3-month mortality 2

  • Focus on monitoring for disease progression every 3–6 months 2
  • Screen for and manage cirrhosis complications (varices, ascites, encephalopathy) 2

• MELD 15–24: Moderate to high risk; ~20–30% 3-month mortality 1, 2

  • Immediate transplant evaluation required 1, 4
  • Actively list and prioritize for organ allocation 2

• MELD ≥25: Very high risk; >30% 3-month mortality 1, 2

  • Highest transplant priority 2
  • Caution: MELD >30–35 associated with increased post-transplant mortality and morbidity; careful candidacy assessment required 1, 5, 6

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Clinical Applications Beyond Transplant Allocation

MELD accurately predicts short-term mortality across multiple clinical scenarios: 1, 3

• Decompensated cirrhosis (any cause) 1
• Variceal bleeding 1, 3
• Hepatorenal syndrome 1, 3
• Hepatopulmonary syndrome 1
• Alcoholic hepatitis (MELD ≥18 indicates poor prognosis) 2, 3
• Perioperative risk assessment for cirrhotic patients undergoing non-hepatic surgery 1
• Post-TIPS survival prediction (pooled AUC 0.81 for 90-day mortality) 1

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Enhanced MELD Variations

MELD-Na (Sodium-Adjusted MELD)

MELD-Na improves mortality prediction by incorporating serum sodium, which is an independent predictor of death in cirrhotic patients with ascites. 1

• Range: 6 to 40 1
• Advantage: Better captures mortality risk in patients with hyponatremia (sodium <130 mmol/L), especially those with low baseline MELD scores 1
• Current use: Standard for transplant allocation in the United States 1

MELD 3.0 (Latest Version)

MELD 3.0 adds serum albumin and patient sex to reduce gender disparities and improve discrimination: 1, 7

• C-statistic: 0.869 vs. 0.862 for MELD-Na 2, 7
• Impact: Correctly reclassifies 8.8% of decedents to higher MELD tiers, particularly benefiting women 7
• Status: Not yet widely recommended for routine clinical practice 1

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Management Algorithm Based on MELD Score

MELD ≥15: High-Risk Population — Immediate Actions Required

Refer promptly for liver transplantation evaluation. 1, 4

1. Engage multidisciplinary transplant team 1
2. Monitor MELD score regularly (weekly to monthly depending on clinical stability) 1
3. Screen for and aggressively manage acute complications: 1, 2
   • Ascites (including spontaneous bacterial peritonitis)
   • Hepatic encephalopathy
   • Variceal bleeding
   • Acute kidney injury / hepatorenal syndrome
4. Screen for hepatocellular carcinoma (HCC) — may qualify for MELD exception points 1, 2
5. Assess for other MELD exceptions: 1, 4
   • Hepatopulmonary syndrome
   • Portopulmonary hypertension
   • Refractory ascites
6. Consider living donor liver transplantation, especially at MELD ≥23, to avoid progressive decompensation while waiting 4

MELD <15: Lower-Risk Population — Surveillance and Complication Management

1. Monitor for disease progression with MELD reassessment every 3–6 months 1, 2
2. Treat specific cirrhosis complications: 1, 2
   • Variceal screening and prophylaxis
   • Ascites management
   • Hepatic encephalopathy treatment
3. Consider transplant evaluation if: 1, 2
   • MELD rises to ≥15
   • Major decompensation occurs (ascites, variceal bleeding, encephalopathy) despite optimal medical management
   • HCC develops
   • Hepatopulmonary syndrome, portopulmonary hypertension, or refractory ascites emerges

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Critical Limitations and Pitfalls

Laboratory-Related Issues

• Creatinine unreliability: 1, 2

  • Overestimates renal dysfunction in sarcopenic patients (low muscle mass)
  • Underestimates renal dysfunction in fluid-overloaded patients

• INR variability: 1

  • Exhibits the greatest inter-laboratory variability
  • Originally designed for warfarin monitoring, not liver disease coagulopathy
  • May be artificially elevated in patients on warfarin or with Fontan circulation 2

Clinical Variables Not Captured by MELD

MELD does not account for clinically significant prognostic factors: 1, 2

• Ascites severity
• Hepatic encephalopathy grade
• Variceal bleeding history
• Nutritional status and sarcopenia
• Frailty
• HCC burden
• Hepatopulmonary syndrome
• Portopulmonary hypertension

MELD Exception Points Required For:

Certain conditions warrant standardized exception points because MELD inadequately reflects their mortality risk or transplant benefit: 1, 4

• Hepatocellular carcinoma 1, 2, 4
• Hepatopulmonary syndrome 1, 4
• Portopulmonary hypertension 1, 4
• Refractory ascites 1, 4

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Common Clinical Pitfalls to Avoid

1. Do not delay transplant referral while awaiting further clinical deterioration when MELD ≥15. 1, 2

2. Do not rely on MELD alone in patients with HCC or other conditions meriting exception points. 1, 2

3. Do not ignore clinical decompensation (ascites, encephalopathy, variceal bleeding) even if MELD appears borderline. 1, 2

   • The presence of ascites alone carries significant mortality risk and is an indication for transplant referral independent of MELD score. 4

4. Do not use MELD as the sole criterion for transplant candidacy in patients with very high scores (>30–35), as post-transplant mortality increases. 1, 5, 6

5. Do not transfuse plasma solely to "correct" INR in non-bleeding patients — INR serves as a prognostic marker, not a therapeutic target. 1

6. Recognize gender disparities: Female patients may have worse outcomes than predicted by MELD alone due to lower creatinine values despite equivalent renal dysfunction. 2, 7

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Integration with Child-Pugh Score

Child-Pugh classification remains an independent prognostic factor and should be used alongside MELD for comprehensive risk stratification. 1, 2

Overlapping Parameters

• Serum bilirubin 2
• Prothrombin time / INR 2

Unique to Child-Pugh

• Serum albumin 2
• Ascites (subjective clinical assessment) 2
• Hepatic encephalopathy (subjective clinical assessment) 2

Comparative Advantages

• MELD: Entirely objective, continuous scale, includes renal function, validated for transplant allocation 1, 2
• Child-Pugh: Includes clinical parameters (ascites, encephalopathy), can be performed at bedside, classifies compensated vs. decompensated cirrhosis 2

It remains unclear whether MELD is superior to Child-Pugh for predicting survival in cirrhotic patients not on transplant waiting lists. 2