MELDscoren

The MELD score, which stands for Model for End-Stage Liver Disease, is a numerical scale used to assess the severity of chronic liver disease. It was initially developed to predict the risk of mortality within three months for patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) procedures. However, its application has expanded significantly, and it is now widely used to prioritize patients for liver transplantation.

The MELD score is calculated using a formula that incorporates four routine laboratory values: bilirubin, creatinine, and the international normalized ratio (INR) of prothrombin time, along with the patient's serum sodium level. Higher values in these tests generally indicate more severe liver dysfunction, leading to a higher MELD score. For instance, a higher bilirubin level suggests the liver is not effectively processing waste products, elevated creatinine can indicate kidney problems often associated with advanced liver disease, and a higher INR points to impaired blood clotting due to reduced liver synthetic function. Low serum sodium can also be a sign of decompensated liver disease.

The score ranges from 6 to 40, with higher scores signifying a greater risk of mortality and a more urgent need for a liver transplant. The United Network for Organ Sharing (UNOS) in the United States uses the MELD score as a primary criterion for allocating liver organs to candidates on the transplant waiting list. This system aims to ensure that organs are given to those who need them most urgently, thereby optimizing the use of scarce donor livers and improving survival rates for patients with end-stage liver disease. Adjustments to the MELD score exist for specific conditions such as hepatocellular carcinoma, allowing for a more personalized risk assessment.