Histological long‐term outcomes from acute antibody‐mediated rejection following ABO‐compatible liver transplantation

Background and aim Acute antibody-mediated rejection (aAMR) is an unusual complication after orthotopic ABO-compatible liver transplantation. To date, the clinical and histological long-term outcomes after aAMR are not well known. Method Herein, we describe 9 cases of aAMR that occurred in our liver-transplant center between 2008 and 2016, with an initial and reevaluation liver biopsy available for reexamination. Results Two patients presented with aAMR at 10.5 [10–11] days post-transplantation, caused by preformed DSAs. Seven other recipients developed de novo DSAs and aAMR at 11.2 [3–24] months post-transplantation. Eight of the 9 patients received a B-cell targeting agent (rituximab, with or without plasma exchange), associated with polyclonal antibodies (three patients) or intravenous immunoglobulins (three patients). At the last follow-up (i.e., 21 [4–90] months post-aAMR) seven patients were alive, including two patients with normal liver tests. Grafts’ survival was 66%. A liver biopsy performed at 11.5 (5–48.5) months after the first biopsy showed no significant improvement in aAMR score (from 2 ± 1.3 to 1.6 ± 1.5, p = 0.6), a significant improvement in chronic AMR score (from 37 ± 9 to 25 ± 8, p = 0.003) and an increase in the Metavir score (1.2 ± 0.6 to 2.1 ± 0.9, p = 0.03). Conclusion in this study a B-cell depleting agent seemed to improve the prognosis of aAMR in selected cases, but several patients kept active lesions antibody mediated rejection.