Pathogenesis in ABO incompatible liver transplantation: a clinicohistological evaluation of four patients.

The aim of this study was to clarify the pathogenesis of antibody-mediated rejection (AMR) of ABO-incompatible liver transplantation (ABO-I-LT). We investigated, within one month of surgery, the clinical courses of 10 patients who received ABO-I-LT. We encountered four cases of AMR, which were classified into two groups according to the stage of the AMR: early (within the first 14 postoperative days [PODs]) or late (after the 14th POD). There were three patients in the early stage, and one patient in the late stage. Three early-stage AMR patients had both hyperbilirubinemia and thrombocytopenia within one month after LDLT, but the one late-stage AMR patient had neither. On liver biopsy, hemorrhagic infiltration was seen more frequently in the early-stage AMR patients than in the patient with late-stage AMR. Plasma exchange combined with a large amount of gamma-globulin bolus infusion therapy was effective in the three early-stage patients, but the late-stage AMR was controlled by antibiotic treatment. This study showed that the early-stage AMR resulted from the antigen-antibody reaction of ABO-blood-group antigens, while the late-stage AMR may have been caused by an infection.