Clinically relevant differences in the model for end-stage liver disease and model for end-stage liver disease-sodium scores determined at three university-based laboratories of the same area

Abstract

The Model for End-Stage Liver Disease (MELD) score is considered an objective and reliable measure of liver disease severity. However, the use of specific laboratory methodologies may introduce significant and clinically relevant variations into the score. It has been suggested that the incorporation of sodium into MELD (MELD-Na) can provide a more accurate survival prediction than MELD alone. Before implementing organ allocation based on the MELD score in an area with 3 transplant centers, we studied whether there were significant variations in MELD and MELD-Na scores determined at each center. Seventy patients on the waiting list were studied simultaneously. Blood samples for each patient were divided into 3 aliquots and were processed in the 3 laboratories in order to calculate MELD and MELD-Na scores. There were statistical differences between the 3 laboratories in the MELD and MELD-Na scores and their parameters. The MELD score was identical in the 3 laboratories for only 6 of the 70 patients, and the MELD-Na score was identical for only 9. MELD and MELD-Na scores from 2 laboratories differed by 1 point or more in 54% and 47% of cases, respectively. Our study confirms that there is major variability in the MELD score, serum sodium, and MELD-Na score. These differences are clinically relevant, and in order to guarantee equitable organ allocation based on the MELD score, similar laboratory methodologies should be implemented at all centers in the same organ procurement area. Alternatively, the possibility of setting up a central laboratory in each organ procurement area should be considered.