Role of Autoimmunity in Patients Transplanted for Acute Liver Failure of Unknown Origin: A Clinical and Graft Biopsy Analysis.

The etiology and prognosis of acute liver failure (ALF) remains unknown in a significant proportion of cases. Signs of autoimmunity may be present, but no consistent pattern has been observed. We aimed to analyze if pretransplant immunological findings, human leukocyte antigen (HLA) haplotypes, and clinical features among patients with an unknown etiology differ from those of autoimmune or other known etiologies. We also analyzed whether such signs impact posttransplant biopsy findings or complications. All adult ALF patients undergoing liver transplantation (LT) in Finland during 1987-2015 were followed to 2016. Data were collected from the LT registry, pathology database, and patient records. A total of 124 patients were included in the analysis. Study subgroups were acute autoimmune hepatitis (AIH; n = 25), known non-AIH etiology (n = 54), and unknown etiology (n = 45). The unknown etiology group differed from the known non-AIH group with regard to the following pretransplant autoimmunity-associated features: positive perinuclear anti-neutrophil cytoplasmic antibodies (36% versus 8%; P = 0.02) and higher mean immunoglobulin A (IgA; 3.2 ± 1.7 versus 2.1 ± 1.4, P = 0.006) and immunoglobulin G (IgG; 12.7 ± 4.3 versus 8.5 ± 3.6, P = 0.001). AIH-associated HLA haplotypes B8, DR3, and B8DR3 were more common in the AIH group (40%, 44%, and 36%, respectively) and in the unknown group (29%, 33%, and 29%, respectively) than in the known non-AIH group (11%, 17%, and 11%, respectively) or in the Finnish general population (17%, 18%, and 8%, respectively). However, these findings had no association with protocol biopsies, extrahepatic autoimmune diseases, or survival. Patients with ≥ 1 rejection episode had higher pretransplant IgA (3.7 ± 2.3 versus 2.6 ± 1.2; P = 0.02) and IgG (16.4 ± 10.2 versus 12.4 ± 6.8; P = 0.03) than those without rejections. Autoimmunity-associated pretransplant laboratory findings and HLA haplotypes were common in ALF of unknown etiology, but they showed minimal predictive value for posttransplant biopsy findings, clinical complications, or survival.