We analyzed the outcomes of ABO compatible and DSA positive living donor liver transplantation (LDLT) focusing on preformed or de novo donor specific anti-HLA antibody (DSA).Patients and Methods
We have decided immunosuppression protocol including portal infusion (PI) therapy depending on the results of lymphocyte cytotoxicity test (LCT) and ABO incompatibility. In all cases, we employed 3 drugs (CNI, antimetabolite, and steroid) for systemic immunosuppression. In ABO compatible and LCT negative cases, we used PGE1 for PI therapy. In ABO compatible and LCT positive cases, we used PGE1 and gabexate mesylate for PI therapy. In ABO incompatible (ABOI) cases, we used 3 drugs (PGE1, gabexate mesylate, and steroid) for PI therapy in addition to plasma exchange and rituximab. We investigated following 2 issues. I) Preformed DSA: Twenty-five recipients whose anti-HLA antibody test (screening test, PRA) was examined were divided into 4 groups depending on the result of (PRA and ABO incompatible (ABOI))=(-, -), (+, -), (-, +), (+, +), and 6-month survival was assessed in each group. In the group of (+, -), anti-HLA antibody test (single antigen test, Luminex) was performed and preformed DSA positive recipients were identified. II) De novo DSA: In the 273 LDLTs, recipients who developed antibody mediated rejection (AMR) were retrospectively identified and the outcomes were assessed.Results
I) Six-month survivals were 62, 81, 100, 100% in (-, -), (+, -), (-, +), and (+, +), respectively. Out of the 9 patients in (+, -), 4 recipients were strongly positive for preformed DSA (>10,000MFI). All 4 recipients were adult female. There were 3 cases of PBC and 1 case of hepatitis C. All of them postoperatively received immunosuppression including PI therapy and their postoperative courses were uneventful. None of them developed AMR. II) Four recipients were identified to have developed AMR postoperatively. Two of them (cases 1 and 2) developed AMR in 2008 and 2010 and DSA was not determined in these years, but their pre and postoperative results of LCT suggested that de novo DSA appeared. Two of them (cases 3 and 4) developed AMR in 2015 and 2016 and DSA was negetive preoperatively but became strongly positive postoperatively. Three (cases 1 to 3) died of AMR and 1 (case 4) survived after re-transplantation. Three (cases 1, 3, and 4) did not receive PI therapy because of individual reasons.Conclusion
Outcomes of recipients who had preformed DSA was satisfactory but those of recipients who developed do novo DSA was poor. Our immunosuppression protocol including PI therapy may be associated with the outcomes.