title: Monitoring of anti-transglutaminase autoantibodies in pediatric celiac disease using a sensitive radiobinding assay.
abstract: OBJECTIVE
  The diagnosis of celiac disease (CD) is based on the histological identification of gluten-sensitive enteropathy and detection of anti-tissue transglutaminase antibodies (tTGA) and/or endomysial antibodies. Serial measurements of tTGA are now recommended as a follow-up strategy to monitor compliance with a gluten-free diet (GFD). We evaluated the performances of a quantitative radiobinding assay (RBA) of tTGA immunoglobulin A at diagnosis and during monitoring of GFD in pediatric CD.
  
  
  METHODS
  Eighty children with confirmed CD were selected. Levels of serum tTGA measured by RBA and a commercial enzyme-linked immunosorbent assay (ELISA) were compared at diagnosis. The relation between RBA-tTGA levels and histological damage was analyzed, as well as the time course of tTGA clearance during GFD.
  
  
  RESULTS
  Both RBA and ELISA showed high sensitivity and specificity for tTGA detection at diagnosis. There was no relation between RBA-tTGA levels at diagnosis and severity of mucosal damage. Upon initiation of GFD, the rate of RBA-tTGA positivity declined slower than that of endomysial antibodies positivity, with >50% of the children still tTGA positive at year 5; however, tTGA levels decreased rapidly during the first year of GFD and more slowly thereafter. Children who seroreverted had lower tTGA levels at diagnosis (2080±1554 cpm) than those who remained tTGA positive throughout follow-up (3688±1435 cpm).
  
  
  CONCLUSIONS
  The high sensitivity of RBA is likely responsible for higher tTGA positivity rates during GFD than previously reported with ELISA. A decreasing trend for tTGA levels may represent a better surrogate marker of compliance with GFD than absolute normal tTGA levels.
authors: Université Paris Descartes, Sorbonne Paris Cité, Paris, France. sophie.candon@inserm.fr
authors: Sophie
authors: S
authors: Candon
authors: François-Xavier
authors: FX
authors: Mauvais
authors: Hélène
authors: H
authors: Garnier-Lengliné
authors: Lucienne
authors: L
authors: Chatenoud
authors: Jacques
authors: J
authors: Schmitz
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002446:Celiac Disease / Q000097:blood / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D055050:Diet, Gluten-Free; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007223:Infant; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D010349:Patient Compliance; D011869:Radioligand Assay / Q000592:standards*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011503:Transglutaminases / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D007070:Immunoglobulin A; D011503:Transglutaminases