The significance of autoantibodies and immunoglobulins in acute liver failure: A cohort study

BackgroundlAinns: The cause of cryptogenic('seronegative') acute liver failure (ALF) is unknown; the presence of nonorgan specific autoantibodies (NOSA) may indicate an autoimmune pathogenesis. We investigated the prevalence of autoimmune features including antibodies to soluble liver antigen (anti-SLA) determined by Radioligand assay (RLA) in ALF patients. Methods: The prevalence and relationship to the immunoglobulin (Ig) response of NOSA and anti-SLA were determined in 73 ALF patients of different causes. Patients were scored using the revised system for diagnosis of autoimmune hepatitis (AIH). Results: Autoantibodies were present in 23 (32%) patients; 16 had anti-SLA, 6 ANA, 4 ASM and 1 AMA. They were absent in paracetamol-related disease and present in 23 of 53 (43%) of non-paracetamol (NP) cases (p < 0.0003). Two of 16 (13%) with NP drug-induced (NPDI), 9 of 21 (43%) viral and 5 of 16 (31%) cryptogenic cases had anti-SLA. NOSA and anti-SLA were not associated with liver injury severity or outcome. IgM was higher in those with viral disease (p < 0.00001). AIH scores classified 50%r of cryptogenic cases as `probable autoimmune hepatitis'. Conclusions: Autoantibodies are common in ALF; cryptogenic cases have features suggestive of an autoimmune pathogenesis. IgM is elevated in viral cases but infrequently in ALF of other causes. (c) 2007 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.