title: Diagnostic utility of modified gliadin peptide antibody assays in New Zealand children.
abstract: OBJECTIVE
  The aim of the present study was to evaluate a panel of different antibody assays, including second-generation antigliadin kits, in a local paediatric population thought to be at risk for coeliac disease (CD).
  
  
  METHODS
  Seventy-nine children, who tested positive for immunoglobulin A (IgA) antibodies to tissue transglutaminase (TG), underwent duodenal biopsy. At endoscopy, serum was collected from all of the patients, and 9 different coeliac antibody assays were performed, both as isolated assays and in combination. These included immunoglobulin A (IgA) anti-tissue transglutaminase (TGA), and IgA plus IgG anti-deamidated gliadin peptide (DGPAG). A diagnosis of CD was made if the biopsies showed Marsh grade 3 lesions.
  
  
  RESULTS
  Twenty-four of 79 children had CD confirmed histologically. Only 39 of 79 were positive for Inova TGA, and 35 of 79 were positive for Inova DGPAG. Twenty-four of 39 who were TGA positive and 24 of 35 who were DGPAG positive had confirmed CD on biopsy. There was good correlation between TGA and DGPAG-positive predictive values. None of the modified gliadin tests produced false-negative results, and neither did the TGA.
  
  
  CONCLUSIONS
  The Inova DGPAG and TGA assays have similar use in predicting CD in a selected paediatric population; however, in children who are positive for TGA when screened for CD, more than half have negative TGA serology when repeat testing is done at the time of biopsy. Those with persistent TGA positivity have only a 61.5% probability of having histologic CD, compared with 68.6% of those children positive for DGPAG.
authors: King's College Hospital, Denmark Hill, London, UK.
authors: Benjamin C
authors: BC
authors: Hope
authors: Rohan
authors: R
authors: Ameratunga
authors: Paul M
authors: PM
authors: Austin
authors: Helen M
authors: HM
authors: Evans
authors: Jeannette
authors: J
authors: MacFarlane
authors: Stephen
authors: S
authors: Mouat
authors: Simon E
authors: SE
authors: Chin
mesh_terms: D000293:Adolescent; D001706:Biopsy; D002446:Celiac Disease / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D004386:Duodenum / Q000276:immunology / Q000473:pathology; D005260:Female; D019204:GTP-Binding Proteins / Q000037:antagonists & inhibitors; D005903:Gliadin / Q000037:antagonists & inhibitors*; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis*; D007074:Immunoglobulin G / Q000032:analysis*; D007223:Infant; D008297:Male; D008403:Mass Screening / Q000379:methods*; D009520:New Zealand / Q000453:epidemiology; D010455:Peptides / Q000037:antagonists & inhibitors*; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011933:Reagent Kits, Diagnostic; D012306:Risk; D012698:Serologic Tests; D011503:Transglutaminases / Q000037:antagonists & inhibitors
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D010455:Peptides; D011933:Reagent Kits, Diagnostic; D005903:Gliadin; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins