title: Specific celiac disease antibodies in children on a gluten-free diet.
abstract: OBJECTIVE
  Celiac disease (CD) is characterized by histologic alterations in small bowel biopsies. Circulating specific CD antibodies at the time of diagnosis and their disappearance after a gluten-free diet support the diagnosis of CD. We aimed to determine the behavior of the CD antibodies immunoglobulin A anti-tissue transglutaminase (anti-TG2) and immunoglobulin A endomysium (EMA) in children with CD after starting a gluten-free diet.
  
  
  METHODS
  This was a retrospective multicenter study in the Netherlands between 2001 and 2009. Inclusion criteria were all newly diagnosed patients with CD younger than 19 years who had at least 1 anti-TG2 and/or EMA measurement before and after starting a gluten-free diet. Eight different anti-TG2 kits were used with substrates of guinea pig TG2 in 1 (Sigma) and 7 human-recombinant TG2: Varelisa and EliA Celikey Phadia-GmbH; Orgentec Diagnostica-GmbH; Diarect AG; Roboscreen GmbH; Aeskulisa Diagnostics; Binding Site Ltd. EMA was analyzed with indirect immunofluorescence tests. Statistical analyses were performed by using mixed-model repeated measurements and survival analysis.
  
  
  RESULTS
  There were 129 children with CD included (mean age: 5.6 years; SD ± 4.2). The mean concentration of anti-TG2 decreased significantly within 3 months after starting a gluten-free diet (P < .0001). The cumulative percentage of children who became negative for EMA after ½, 1, 1½, and 2 years was 31%, 60%, 74%, and 87%, respectively. For anti-TG2, a comparable trend was shown: 35%, 55%, 64%, and 78%, respectively.
  
  
  CONCLUSIONS
  Doctors taking care of children with CD should be aware that the mean concentration of anti-TG2 will show a 74% decrease (95% confidence interval: 69%-79%) after 3 months of gluten-free diet, and ∼80% of the children will be sero-negative for EMA and anti-TG2 after 2 years of the diet.
authors.affiliation: Department of Pediatric Gastroenterology, Leiden University Medical Centre, Leiden, Netherlands. c.e.hogen_esch@lumc.nl
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Hogen Esch
authors.forename: Victorien M
authors.initials: VM
authors.lastname: Wolters
authors.forename: Susan A M
authors.initials: SA
authors.lastname: Gerritsen
authors.forename: Hein
authors.initials: H
authors.lastname: Putter
authors.forename: B Mary
authors.initials: BM
authors.lastname: von Blomberg
authors.forename: Ingrid M W
authors.initials: IM
authors.lastname: van Hoogstraten
authors.forename: Roderick H J
authors.initials: RH
authors.lastname: Houwen
authors.forename: Nico
authors.initials: N
authors.lastname: van der Lely
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Mearin
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D001323:Autoantibodies / Q000276:immunology; D002446:Celiac Disease / Q000178:diet therapy* / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D055050:Diet, Gluten-Free; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D019204:GTP-Binding Proteins / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology*; D007223:Infant; D007413:Intestinal Mucosa / Q000276:immunology; D008297:Male; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D012189:Retrospective Studies; D011503:Transglutaminases / Q000276:immunology*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D001323:Autoantibodies; D007070:Immunoglobulin A; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins