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

Background/Aims The cause of cryptogenic (‘seronegative’) acute liver failure (ALF) is unknown; the presence of non-organ 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% 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.