The Dynamic MEAF Calculator is a web-based service, which intends to assist surgeons and researchers interested in liver transplantation. It enables the calculation of the MAEF ALT/AST score which evaluate early allograft function. This score is designed to evaluate graft function during the early postoperative days after liver transplantation.
It is based on the MEAF-score published by Pareja et al. in 2015. It has been modified to be applicable to most liver transplant patients. This new score would help us to predict more accurately the degree of dysfunction and the survival of the liver graft in the early postoperative time, providing a work tool with a high capacity for reproducibility and applicability in routine clinical practice.
It can be calculated every day since the 2nd until the 5th postoperative day. For each of the days of its calculation, two formulas are obtained: MEAF ALT and MEAF AST. Unlike other scores, it is not necessary to have all the data until the 5th postoperative day.
The variables are the maximum level of INR until the day of the score’s calculation, the maximum level of ALT or AST until the day of the score’s calculation, and the value of the bilirubin at the day of score’s calculation, calculated in mg/dl or in mol/L.
It is a dual score, and it can be calculated with ALT or AST. The score is a number between 0 (good function of the liver graft) and 10 (good function of the liver graft). The scores of the MEAF-ALT and for the MEAF-AST for each of the days is represented in two graphs, showing dynamic information about the function of the graft.
Applicability
Can be calculated in:
- Recipients with donation after brain death
- Recipients with grafts from donation after circulatory death
- Recipients with fulminant hepatitis
- Biliary cirrhosis
- Sclerosing cholangitis
- Simultaneous kidney transplant
- Reduced grafts or Split
- Retransplants
Cannot be applied for:
- Paediatrics recipients (<18 years)
- Liver transplants from living donors
- Domino liver transplants
- Multivisceral recipients (except patients simultaneously receiving kidney grafts)
- Grafts with vascular complications
- Recipients retransplanted before the 2nd postoperative day
- Death before the 2nd postoperative day
Validation & Graft Survival
The MAEF-AST score has been validated in an independent patient cohort, underlining its reproducibility.
The score can be used to predict graft survival before the 10th postoperative days. To evaluate graft survival, ROC (Receiver Operating Characteristic) curve and the values of area under the ROC curve (AUC) are used.
Validation Metrics
| Metric | Specificity | Sensitivity | AUC |
|---|---|---|---|
| MEAF-ALT Day 2 | 0.87 | 0.70 | 0.79 |
| MEAF-ALT Day 3 | 0.81 | 0.75 | 0.80 |
| MEAF-ALT Day 4 | 0.88 | 0.75 | 0.82 |
| MEAF-ALT Day 5 | 0.84 | 0.67 | 0.77 |
| Metric | Specificity | Sensitivity | AUC |
|---|---|---|---|
| MEAF-AST Day 2 | 0.78 | 0.70 | 0.80 |
| MEAF-AST Day 3 | 0.84 | 0.75 | 0.80 |
| MEAF-AST Day 4 | 0.90 | 0.75 | 0.82 |
| MEAF-AST Day 5 | 0.75 | 0.73 | 0.76 |
The limitation of this score is that it has high specificity, but with lower sensitivity. Which implies that the final decision to retransplant is based on clinical criteria and the experience of the transplant center. However, we consider that by dynamically assessing from the 2nd to the 5th postoperative days it could help teams make the decision to re-transplant in the event of graft failure.
References
- Pareja E, Cortes M, Hervás D, Mir J, Valdivieso A, Castell JV, et al. A score model for the continuous grading of early allograft dysfunction severity. Liver Transpl. 2015;21(1):38-46.
- Payá Llorente, C. Desarrollo y validación de un modelo predictivo continuo para valorar la función inicial del injerto tras el trasplante hepático: comparación con modelos existentes. Valencia. 2024