Testing for IgG class antibodies in celiac disease patients with selective IgA deficiency. A comparison of the diagnostic accuracy of 9 IgG anti-tissue transglutaminase, 1 IgG anti-gliadin and 1 IgG anti-deaminated gliadin peptide antibody assays

Clin Chim Acta. 2007 Jul;382(1-2):95-9. doi: 10.1016/j.cca.2007.03.028. Epub 2007 Apr 13.


Background: To evaluate the diagnostic characteristics of commercially available IgG anti-tTG assays in selective IgA deficiency (SIgAD), we tested different IgG anti-tTG methods and compared the results with those obtained from two other tests: one for IgG anti-gliadin (AGA) and one for IgG to deaminated gliadin peptides (DGP).

Methods: 20 CD patients with SIgAD and 113 controls (9 patients with SIgAD without CD; 54 patients with chronic liver disease; 50 healthy subjects) were tested with 9 IgG anti-tTG assays (2 of which are enriched with gliadin peptides), one IgG AGA assay and one IgG anti-DGP assay.

Results: Using optimal cutoffs as determined by ROC curves, the sensitivity of IgG anti-tTG methods ranged from 75% (1 kit) to 95% (7 kits) and the specificity from 94% (1 kit) to 100% (5 kits). Sensitivity and specificity were 40% and 87% for IgG AGA, and 80% and 98% for IgG anti-DGP, respectively.

Conclusions: All IgG anti-tTG methods evaluated are reliable serologic assays for the diagnosis of CD in patients with SIgAD and perform better than the gliadin-based assays used in this study. The tests containing both tTG and gliadinic peptides are burdened by a lower specificity than the anti-tTG assays.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Adolescent
  • Adult
  • Autoantibodies / blood*
  • Celiac Disease* / diagnosis
  • Celiac Disease* / immunology
  • Child
  • Child, Preschool
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Gliadin / immunology*
  • Humans
  • IgA Deficiency / blood
  • IgA Deficiency / immunology
  • Immunoglobulin G / blood*
  • Male
  • Middle Aged
  • Reagent Kits, Diagnostic*
  • Sensitivity and Specificity
  • Transglutaminases / immunology*


  • Autoantibodies
  • Immunoglobulin G
  • Reagent Kits, Diagnostic
  • Gliadin
  • Transglutaminases