title: Diagnostic criteria of autoimmune hepatitis.
abstract: Autoimmune hepatitis (AIH) is a chronic immune-mediated liver disorder characterised by female preponderance, elevated transaminase and immunoglobulin G levels, seropositivity for autoantibodies and interface hepatitis. Presentation is highly variable, therefore AIH should be considered during the diagnostic workup of any increase in liver enzyme levels. A set of inclusion and exclusion criteria for the diagnosis of AIH have been established by the International Autoimmune Hepatitis Group (IAIHG). There are two main types of AIH: type 1, positive for anti-nuclear (ANA) and/or anti-smooth muscle antibodies (SMAs) and type 2, defined by the presence of anti-liver kidney microsomal antibody type 1 (LKM-1) and/or anti-liver cytosol type 1 (LC-1) autoantibodies. The central role of autoantibodies in the diagnosis of AIH has led the IAIHG to produce a consensus statement detailing appropriate and effective methods for their detection. Autoantibodies should be tested by indirect immunofluorescence at an initial dilution of 1/40 in adults and 1/10 in children on a freshly prepared rodent substrate that includes kidney, liver and stomach sections to allow for the simultaneous detection of all reactivities relevant to AIH. Anti-LKM-1 is often confused with anti-mitochondrial antibody (AMA) if rodent kidney is used as the sole immunofluorescence substrate. The identification of the molecular targets of anti-LKM-1 and AMA has led to the establishment of immuno-assays based on the use of the recombinant or purified autoantigens. Perinuclear anti-nuclear neutrophil antibody (p-ANNA) is an additional marker of AIH-1; anti soluble liver antigen (SLA) antibodies are specific for autoimmune liver disease, can be present in AIH-1 and AIH-2 and are associated with a more severe clinical course. Anti-SLA are detectable by ELISA or radio-immuno-assays, but not by immunofluorescence. AIH is exquisitely responsive to immunosuppressive treatment, which should be instituted promptly to prevent rapid deterioration and promote remission and long-term survival.
authors.affiliation: Paediatric Liver, GI & Nutrition Centre and Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, London, UK; Faculty of Medicine, University of Porto, Porto, Portugal.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Liberal
authors.affiliation: Paediatric Liver, GI & Nutrition Centre and Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, London, UK.
authors.forename: Charlotte R
authors.initials: CR
authors.lastname: Grant
authors.affiliation: Paediatric Liver, GI & Nutrition Centre and Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, London, UK.
authors.forename: Maria Serena
authors.initials: MS
authors.lastname: Longhi
authors.affiliation: Paediatric Liver, GI & Nutrition Centre and Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, London, UK.
authors.forename: Giorgina
authors.initials: G
authors.lastname: Mieli-Vergani
authors.affiliation: Paediatric Liver, GI & Nutrition Centre and Institute of Liver Studies, King's College London School of Medicine at King's College Hospital, London, UK. Electronic address: diego.vergani@kcl.ac.uk.
authors.forename: Diego
authors.initials: D
authors.lastname: Vergani
mesh_terms: D000974:Antibodies, Antinuclear / Q000276:immunology; D001323:Autoantibodies / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D015415:Biomarkers; D019693:Hepatitis, Autoimmune / Q000175:diagnosis* / Q000276:immunology / Q000628:therapy; D006801:Humans
chemical_list: D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D001324:Autoantigens; D015415:Biomarkers; C094307:anti-liver cytosolic protein 1; C060729:anti-liver kidney microsome antibody; C046431:liver antigen LA-1