The Graz Liver Allocation Strategy—Impact of Extended Criteria Grafts on Outcome Considering Immunological Aspects

Abstract

Background: Transplant centers are forced to use livers of extended criteria donors for transplantation due to a dramatic organ shortage. The outcome effect of extended donor criteria (EDCs) remains unclear. Thus, this study was designed to assess the impact of EDCs on outcome including immunological aspects after liver transplantation (LT). Patients and Methods: Between November 2016 and March 2018, 49 patients (85.7% male) with a mean age of 57 ± 11 years underwent LT. The impact of EDCs on outcome after LT was assessed retrospectively using both MedOcs and ENIS (Eurotransplant Network Information System). Results: About 80% of grafts derived from extended criteria donors. Alanine aminotransferase/aspartate aminotransferase (AST/ALT) levels elevated more than three times above normal values in organ donors was the only significant risk factor for primary dysfunction (PDF) and primary non-function (PNF)/Re-LT and early non-anastomotic biliary strictures (NAS). Balance of risk (BAR) score did not differ between EDC and non-EDC recipients. PDF (14.3% of all patients) and PNF (6.1% of all patients) occurred in 23.1% of EDC-graft recipients and in 10.0% of non-EDC-graft recipients (RR 2.31, p = 0.663). The 90-day mortality was 3.6%. There was no difference of early non-anastomotic biliary tract complications and biopsy proven rejections (BPR). There was no correlation of PDF/PNF with BPR and NAS, respectively; however, 66.7% of the patients with BPR also developed early NAS ( p < 0.001). Conclusion: With the Graz liver allocation strategy, excellent survival can be achieved selecting livers with no more than 2 not outcome-relevant EDCs for patients with MELD >20. Further, BPR is associated with biliary complications.

Machine Perfusion for Extended Criteria Donor Livers: What Challenges Remain?

“…The threshold of >30 or even >35 kg/m 2 is, however, more often recognized by many [ 11 , 68 , 71 ] and further supported by the new ILTS consensus guidelines [ 68 ]. Similar categorizations were suggested by Eurotransplant and the EASL guidelines for all ECD grafts ( Table 1 ) [ 13 , 27 ].…”

“…The Eurotransplant definition includes the following criteria for ECDs: donor age > 65 years; intensive care unit (ICU) stay of >7 days with ventilation; body mass index (BMI) > 30 kg/m 2 ; liver steatosis of >40% and elevated serum sodium, transaminases and bilirubin [ 13 , 27 ]. There are, however, numerous reports of successful transplantations with livers exceeding these cut-offs, and from the recent literature, we can see a trend towards benchmark outcomes for ECD allografts [ 28 ].…”

“…The British Transplantation Society (BTS) classifies DCD donors with an ICU stay of ≤5 days as low risk [ 38 ], and in the Eurotransplant region, donors with >7 days ICU stay with ventilation are considered marginal [ 13 , 27 , 93 ].…”

“…Such parameters include the required amount of medical cardiovascular support, the duration of the previous downtime and the levels of donor liver enzymes and function [ 95 ]. The Eurotransplant guidelines suggest the classification of livers as extended when serum transaminases cross the normal values greater than three times ( Table 1 ) [ 13 , 27 ].…”

“…Previously discarded organs are frequently classified as “standard” or even “good quality grafts” today. Based on an increasing number of publications where the authors describe various parameters with an impact on the outcomes, the term ECD covers a pool of grafts from donors with countless risk profiles and specifications that lack a uniform terminology and guidelines [ 13 , 14 , 15 , 16 ].…”