title: Autoantibody Profile of Adult Patients With Childhood Onset Type 2 Autoimmune Hepatitis.
abstract: BACKGROUND
  Anti-liver kidney microsome (anti-LKM) autoantibodies are a distinguishing feature of type II autoimmune hepatitis (AIH-2). However, the levels of anti-LKM-1 in adult AIH-2 patients and their role in liver immunopathology remain equivocal. The aim of the study was to survey the autoantibody profile and the activity of liver disease in adult patients diagnosed with AIH-2 at childhood.
  
  
  METHODS
  The autoantibody profile of adults was compared with the autoantibodies of the pediatric period. Liver function test, Immunoglobulin G (IgG), and gamma globulins were evaluated at the AIH presentation, at the age of 18 years, and at the current adult visit.
  
  
  RESULTS
  All ten patients tested positive for LKM-1 at least once during the pediatric period. At the adult visit, four patients lost autoantibody positivity. LKM-1 was positive in four, liver cytosol antigen 1 (LC-1) in two, soluble liver antigen in one, and antinuclear antigen in one patient. Additionally three patients with LKM-1 and one patient without LKM-1 were positive for AMA-M2 (where AMA is antimitochondrial antibodies) Immunoglobulin M (IgM). Liver function markedly improved at 18 years and adult visit compared with initial diagnosis of AIH with only a mild decrease of IgG. The six adult patients positive for at least one autoantibody had statistically lower aspartate aminotransferase (AST) and gamma-glutamyltranspeptidase (GGTP) than the four patients autoantibody negative (AST: 52 vs. 88 IU/l, P < 0.05; GGTP 19 vs. 163 IU/l, P < 0.05).
  
  
  CONCLUSIONS
  LKM-1 positivity is not a stable condition in all patients with AIH-2. Patients who remained autoantibody positive had better liver function tests than those who lost their positivity. The presence of AMA-M2 autoantibodies suggest that development of AIH/Primary Biliary Cirrhosis (PBC) overlap syndrome should be considered.
authors.affiliation: Children's Health Memorial Institute, Warsaw, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Woynarowski
authors.affiliation: Children's Health Memorial Institute, Warsaw, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Woźniak
authors.affiliation: Children's Health Memorial Institute, Warsaw, Poland.
authors.forename: Bożena
authors.initials: B
authors.lastname: Cukrowska
authors.affiliation: Children's Health Memorial Institute, Warsaw, Poland.
authors.forename: Aldona
authors.initials: A
authors.lastname: Wierzbicka
authors.affiliation: SeraDiaLogistics, Munich, Germany. simon.lytton@t-online.de.
authors.forename: Simon D
authors.initials: SD
authors.lastname: Lytton
mesh_terms: D000328:Adult; D000974:Antibodies, Antinuclear / Q000276:immunology / Q000378:metabolism*; D001323:Autoantibodies / Q000276:immunology / Q000378:metabolism*; D005260:Female; D019693:Hepatitis, Autoimmune / Q000276:immunology*; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D055815:Young Adult; D005719:gamma-Globulins / Q000276:immunology
chemical_list: D000974:Antibodies, Antinuclear; D001323:Autoantibodies; C060729:anti-liver kidney microsome antibody; D005719:gamma-Globulins
keywords: LKM-1; autoantibodies; autoimmune hepatitis