1 Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Paul-List-Str. 13-15, D-04103 Leipzig, Germany.
2 Anesthesiology and Intensive Care Medicine, University Hospital Greifswald, Ferdinand-Sauerbruch-Straße, D-17475 Greifswald, Germany.

✉ Correspondence: Sebastian Gibb <>

Last updated: 2021-08-01

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Introduction

Liver cirrhosis is the terminal result of fibrotic remodeling of liver tissue due to chronic damage. An organ failure is often irreversible and the only available therapy is liver transplantation. However, the shortage in grafts for transplantation from deceased donors requires risk stratification and precise allocation rules. The allocation of liver transplantation in most countries is based on disease severity determined by the model of end-stage liver disease (MELD) (Malinchoc et al. 2000; Wiesner et al. 2003; Organ Procurement and Transplantation Network 2021). The MELD score estimates the patients’ 3-month mortality risk based on laboratory results, namely bilirubin, creatinine and international normalized ratio (INR). In general the MELD score is extended by the sodium level (MELD-Na score) as this was found to be an important additional risk factor in liver cirrhosis (Kim et al. 2008; Organ Procurement and Transplantation Network 2021). The MELD was initially developed for predicting the survival of patients undergoing transjugular intrahepatic portosystemic shunts. Afterwards it was revalidated for predicting mortality risk in patients awaiting a liver transplantation. Although the MELD score should be an objective allocation score especially the creatinine and INR are highly dependent on the utilized laboratory methods (Trotter et al. 2004; Cholongitas et al. 2007). Patients with identical disease state could have very different MELD scores and thus get different priority on the liver transplantation waiting list. Furthermore often, e.g. for acute-on-chronic liver failure, the MELD score underestimates the mortality risk (Hernaez et al. 2020).

There have been some attempts to use the data extracted from more than 300.000 electronic medical records from two hospitals in the United States to improve the MELD score (Kartoun et al. 2017). The derived MELD-Plus7 and MELD-Plus9 risk score add albumin, white blood cell count, age and total cholesterol and length of stay to the MELD-Na variables. Despite its published prediction improvement the MELD-Plus scores are not used for transplant allocation yet.

As depicted by MELD-Plus risk scores better predictive scores often need more variables and are more complicated. To reduce the risk of overlooking or incorrectly calculating and interpreting the results, clinical decision support systems may be used and could improve patient safety. The research project on digital laboratory medicine (AMPEL) develops a clinical decision support system based on laboratory diagnostics that should support clinical practitioners in interpreting the laboratory results and taking the necessary medical interventions (Eckelt et al. 2020).

This study aims to find clinical and laboratory values that improve the risk stratification for liver transplantation over classical MELD, MELD-Na and MELD-Plus scores and could be implemented as part of the AMPEL clinical decision support system.

Material and methods

Results

Discussion

References

Cholongitas, E., L. Marelli, A. Kerry, M. Senzolo, D. W. Goodier, D. Nair, M. Thomas, D. Patch, and A. K. Burroughs. 2007. “Different Methods of Creatinine Measurement Significantly Affect MELD Scores.” Liver Transplantation 13 (4): 523–29. https://doi.org/10.1002/lt.20994.

Eckelt, F., J. Remmler, T. Kister, M. Wernsdorfer, H. Richter, M. Federbusch, M. Adler, et al. 2020. “Verbesserte Patientensicherheit Durch “Clinical Decision Support Systems” in Der Labormedizin.” Der Internist 61 (5): 452–59. https://doi.org/10.1007/s00108-020-00775-3.

Hernaez, R., Y. Liu, J. R. Kramer, A. Rana, H. B. El-Serag, and F. Kanwal. 2020. “Model for End-Stage Liver Disease-Sodium Underestimates 90-Day Mortality Risk in Patients with Acute-on-Chronic Liver Failure.” Journal of Hepatology, June. https://doi.org/10.1016/j.jhep.2020.06.005.

Kartoun, U., K. E. Corey, T. G. Simon, H. Zheng, R. Aggarwal, K. Ng, and S. Y. Shaw. 2017. “The MELD-Plus: A Generalizable Prediction Risk Score in Cirrhosis.” PLOS ONE 12 (10): e0186301. https://doi.org/10.1371/journal.pone.0186301.

Kim, W. R., S. W. Biggins, W. K. Kremers, R. H. Wiesner, P. S. Kamath, J. T. Benson, E. Edwards, and T. M. Therneau. 2008. “Hyponatremia and Mortality Among Patients on the Liver-Transplant Waiting List.” New England Journal of Medicine 359 (10): 1018–26. https://doi.org/10.1056/NEJMoa0801209.

Malinchoc, M., P. S. Kamath, F. D. Gordon, C. J. Peine, J. Rank, and P. C. J. ter Borg. 2000. “A Model to Predict Poor Survival in Patients Undergoing Transjugular Intrahepatic Portosystemic Shunts.” Hepatology 31 (4): 864–71. https://doi.org/10.1053/he.2000.5852.

Organ Procurement and Transplantation Network. 2021. “Policies.” 2021. https://optn.transplant.hrsa.gov/media/1200/optn_policies.pdf.

Trotter, J. F., B. Brimhall, R. Arjal, and C. Phillips. 2004. “Specific Laboratory Methodologies Achieve Higher Model for Endstage Liver Disease (MELD) Scores for Patients Listed for Liver Transplantation.” Liver Transplantation 10 (8): 995–1000. https://doi.org/10.1002/lt.20195.

Wiesner, R., E. Edwards, R. Freeman, A. Harper, R. Kim, P. Kamath, W. Kremers, et al. 2003. “Model for End-Stage Liver Disease (MELD) and Allocation of Donor Livers.” Gastroenterology 124 (1): 91–96. https://doi.org/10.1053/gast.2003.50016.


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