Towards a better liver allocation system

Abstract

failures because primary HB-vaccination failures occur in over 5% of adult vaccinees. Not only awareness that vaccine-induced immunity against HBV can wane over time, but also awareness of which factors are associated with waning immunity is important for preventing HBV infection in general and in the healthcare setting in particular. References[1] Boot HJ, van der Waaij LA, Schirm J, Kallenberg CGM, van Steenbergen J, Wolters B. Acute hepatitis B in a healthcare worker: A case report of genuine vaccination failure. J Hepatol 2009;50:426-431. [2] Wiersma ST. Hepatitis B vaccine continues to provide long-term protection to healthcare workers. Journal of Hepatology [1]. Although we agree that the MELD score is basically a ''justice system" which allocates patients according to severity of liver disease however it is not necessarily the best system [2] and indeed some limitations of the MELD score were totally ignored in the forum mentioned above. For example, significant variations of the MELD score have been found using different laboratory methodologies for INR measurement [3], as well as creatinine (Cr) as we have published [4], and recently MELD-Na [5]. These variations, which may be cumulative when summated, lead to inequalities in prioritization of candidates, especially in those with the highest priority for LT (more jaundiced, greater renal dysfunction and lower serum sodium). A system of allocation that inherently does not have standardized measurements cannot reflect true justice for individuals on waiting lists -this needs to be addressed. Moreover, there is an issue of potential gender bias, highlighted by us [6] and reported by Moylan et al. [7]. In the UNOS database, women were more likely to die on the waiting list in the post-MELD era, compared to the pre-MELD era, although women were listed with lower median MELD scores, compared to men (14 vs. 15, p < 0.001). These findings are likely to be the result of not considering lower Cr in women for the same renal function (GFR), as in men [8], as we documented in our paper [6]. Interestingly, we found that correcting Cr by equalising the GFR between men and women resulted in an increase in MELD score by 2 or 3 points in 65% of female LT candidates [6]. Our findings with Cr are also pertinent to ethnicity differences. South Asian candidates have worse GFR for the same Cr values than Caucasians, and the opposite is true for black Africans, whether Americans or otherwise. A correction factor for gender and ethnicity could be introduced [6].Regarding post-LT survival, it is true that the MELD score is a weak predictor of mortality after LT, so it cannot be used as a predictor. In order to assess likelihood of a good outcome, we have proposed a MELDD score -a second D for donor [2,8]. This would allow a utilitarian approach to allocation on top of the ''solely justice approach" of MELD and would lead to a transplant benefit model for allocation. A recent evaluation of the European Liver Transplant Registry data [9], demonstrated that donor age, total ischaemi...

Prioritization for liver transplantation

“…The latter has been highlighted by us [28], and found also by others [29] and can explain in part why women have higher waiting list mortality, compared to men, in the post-MELD era [29]. In fact, the Cr values in women, represent a worse GFR than in men, for the same Cr values [30]. Thus, a score corrected for female candidates (MELD-gender) has been suggested [31].…”

Prognostic Significance of Ascites and Serum Sodium in Patients with Low Meld Scores

“…There are several other studies that have supported the independent effect of ascites and water retention on disease severity and mortality ( 16 , 20 , 21 ). Heuman et al determined that persistent ascites was an independent predictor of mortality, specifically, ascites and low serum sodium, and not MELD, were the important prognostic factors when the MELD score was less than 21 ( 22 ).…”