What is the MELD (Model for End-Stage Liver Disease) score used for?

What is the MELD Score For?

The MELD (Model for End-Stage Liver Disease) score is primarily used to predict 3-month mortality in patients with end-stage liver disease and to prioritize organ allocation for liver transplantation. 1

Primary Clinical Applications

Liver Transplant Allocation and Prioritization

• The MELD score serves as the primary tool for prioritizing liver transplant allocation in the United States and most European countries, replacing the previous time-based waiting list system. 1, 2
• The score assigns patients a continuous numerical scale from 6 to 40, with higher scores indicating greater short-term mortality risk and therefore higher priority for transplantation. 3
• Patients with MELD ≥15 should be listed for liver transplantation, as this represents the threshold where transplant survival benefit exceeds non-transplant survival. 1, 3 Patients with MELD ≤14 have better 1-year survival without transplantation than with it. 1
• Implementation of MELD-based allocation in 2002 led to a sharp reduction in waiting list deaths and decreased the number of people waiting for transplant without affecting post-transplant survival. 2

Mortality Risk Stratification

• The MELD score accurately predicts short-term (90-day) mortality across multiple clinical scenarios beyond transplant listing, including decompensated cirrhosis, variceal bleeding, hepatorenal syndrome, and hepatopulmonary syndrome. 1, 2
• The score was originally developed to assess prognosis in patients undergoing transjugular intrahepatic portosystemic shunts (TIPS), but its utility has expanded significantly. 4, 3
• Patients with MELD >15 have significantly higher mortality risk compared to those with MELD <15. 5

How the MELD Score Works

Objective Laboratory Parameters

• MELD incorporates three entirely objective laboratory values: serum bilirubin, international normalized ratio (INR), and serum creatinine. 1, 3, 2
• The mathematical formula is: MELD = 3.8 × log(bilirubin mg/dL) + 11.2 × log(INR) + 9.6 × log(creatinine mg/dL) + 6.4. 3
• These three parameters have been identified as the best predictors of 3-month mortality in end-stage liver disease. 3

Key Advantages Over Child-Turcotte-Pugh Score

• MELD uses only objective laboratory criteria, eliminating the subjective assessments of ascites and encephalopathy required by the Child-Turcotte-Pugh (CTP) score. 3, 2
• Unlike CTP, MELD includes renal function (serum creatinine), which is a critical prognostic marker in liver disease. 3
• MELD provides a continuous numerical scale rather than categorical classes, allowing for more precise risk stratification. 3

Clinical Management Algorithm Based on MELD Score

MELD ≥15: High-Risk Population Requiring Immediate Action

• Immediately refer for liver transplantation evaluation at a transplant center. 1
• Engage a multidisciplinary transplant team for comprehensive assessment. 1
• Identify and aggressively treat acute complications of cirrhosis (variceal bleeding, spontaneous bacterial peritonitis, hepatorenal syndrome). 1
• Monitor MELD score regularly (every 1-3 months depending on clinical stability) to track disease progression. 1
• Consider living donor liver transplantation (LDLT) evaluation, particularly if MELD is rising or deceased donor wait times are prolonged. 6

MELD <15: Lower-Risk Population

• Focus on managing specific cirrhosis complications with regular monitoring for disease progression. 1
• Treat complications including ascites, hepatic encephalopathy, and variceal prophylaxis. 1
• Consider transplant evaluation if major complications occur despite optimal medical management, even if MELD remains <15. 1

Important Limitations and Clinical Pitfalls

MELD Exception Conditions

• Certain conditions require "exception points" because MELD inadequately reflects their mortality risk, including hepatocellular carcinoma (HCC), hepatopulmonary syndrome, portopulmonary hypertension, and refractory ascites. 1, 3
• Do not use MELD as the sole criterion for transplant listing in patients with HCC or other exception conditions. 1

Laboratory Value Pitfalls

• Serum creatinine can be unreliable in cirrhotic patients with sarcopenia (underestimating MELD) or fluid overload (overestimating MELD). 1
• INR or creatinine may be elevated due to reasons other than liver disease, potentially inflating the MELD score inappropriately. 2
• MELD does not differentiate between patients with or without ascites, which has independent prognostic significance. 7

Very High MELD Scores

• Patients with MELD >30-35 have increased post-transplant mortality and morbidity, requiring careful assessment of transplant candidacy and optimization before surgery. 1

Clinical Decompensation with Low MELD

• Do not ignore clinical decompensation in patients with low MELD scores. 1 The development of spontaneous bacterial peritonitis or type I hepatorenal syndrome carries extremely poor prognosis (median survival <2 weeks for hepatorenal syndrome) regardless of calculated MELD. 4

Enhanced MELD Variations

• Several modifications have been developed to improve predictive accuracy, including MELD-Na (incorporating serum sodium), Delta MELD (measuring change over time), and MELD 3.0 (adding sex and albumin with reweighted parameters). 1, 3, 8
• MELD 3.0 is expected to reduce overall waitlist mortality modestly and improve access for female liver transplant candidates. 8