How to calculate the Model for End-Stage Liver Disease (MELD) score?

From the Guidelines

The MELD score is calculated using the formula: MELD = 3.8 * log(bilirubin in mg/dL) + 11.2 * log (INR) + 9.6 * log (creatinine mg/dL) + 6.4, as stated in the study published in Hepatology in 2010 1. To calculate the MELD score, you need to use the following laboratory values: serum bilirubin, serum creatinine, and INR (International Normalized Ratio).

• The formula is based on natural logarithms of these values.
• All laboratory values less than 1.0 are set to 1.0 for the calculation, and serum creatinine is capped at 4.0 mg/dL.
• For patients who have had dialysis twice in the last week, the creatinine value is automatically set to 4.0 mg/dL.
• The resulting score ranges from 6 to 40, with higher scores indicating more severe liver disease and greater urgency for liver transplantation. The MELD score helps prioritize patients on the liver transplant waiting list based on their risk of mortality, as recommended by the EASL clinical practice guidelines: liver transplantation in 2016 1. It's essential to note that the score should be recalculated periodically as laboratory values change to accurately reflect the patient's current condition. The MELD score is a good predictor of short-term pre-transplant mortality risk, and it is based on objective laboratory tests, making it suitable for use in organ allocation 1.

From the Research

Calculating MELD Score

To calculate the Model for End-Stage Liver Disease (MELD) score, the following formula is used:

• MELD score = 10 * (0.957 * ln(serum creatinine) + 0.378 * ln(serum bilirubin) + 1.120 * ln(INR)) + 6.43 2, 3
• Where ln is the natural logarithm
• Serum creatinine, serum bilirubin, and INR are the laboratory values used to calculate the MELD score

Components of the MELD Score

The MELD score is based on three objective variables:

• Serum bilirubin: a measure of liver function 2, 3
• Serum creatinine: a measure of kidney function 2, 3
• International normalized ratio (INR): a measure of blood clotting 2, 3

Clinical Applications of the MELD Score

The MELD score has several clinical applications, including:

• Predicting 90-day mortality in patients with cirrhosis 2, 3
• Prioritizing patients for liver transplantation 2, 3
• Predicting outcome in patients with cirrhosis undergoing surgery 2
• Predicting outcome in patients with fulminant hepatic failure or alcoholic hepatitis 2

Limitations of the MELD Score

The MELD score has some limitations, including:

• Inaccuracy in predicting survival in 15-20% of cases 3
• Limited ability to predict mortality in patients with conditions other than liver disease 2
• Does not take into account other factors that may affect liver disease severity, such as hepatic encephalopathy or ascites 4, 5