title: Interpretation of serological tests in the diagnosis of celiac disease: Anti-deamidated gliadin peptide antibodies revisited.
abstract: Algorithms for celiac disease diagnosis provided by guidelines are based primarily on anti-tissue transglutaminase 2 (TG2) antibodies and/or anti-endomysium antibodies. The place of anti-deamidated gliadin peptide (DGP) antibodies is less well established. This study was designed to assess the clinical relevance of anti-DGP antibodies. Two thousand and twenty-six consecutive unselected patients systematically tested for anti-TG2, endomysium, gliadin, DGP antibodies and IgA dosage were investigated. The serological interpretation was assessed by analyzing the medical records of patients. From the 1984 newly investigated patients suspected of celiac disease, 10% had at least one celiac marker. Anti-TG2, anti-endomysium, anti-gliadin and anti-DGP antibodies were found in 1.1%, 0.6%, 6.8% and 4.1% of cases respectively, with different combinations. The diagnosis of celiac disease was retained in 0.45% of patients. When using the duodenal biopsies as a gold standard, analysis of the anti-DGP diagnosis performance showed that the specificity and the predictive positive value (PPV) were lower than that of the anti-TG2 assay. The combined detection of anti-TG2 and anti-DGP antibodies had a lower PPV than that of anti-TG2 and anti-endomysium antibodies (p = 0.04). When analyzing the contribution of anti-DGP antibodies as an additional marker to both anti-TG2 and anti-endomysium antibodies, the PPV of the three associated antibodies was shown to be significantly lower than the PPV of the both anti-TG2 and anti-endomysium antibodies (p = 0.04). As a conclusion, anti-DGP antibodies may not have the diagnosis value required as an additional screening test to anti-TG2 antibodies for identifying celiac disease patients in medical centers where anti-endomysium detection is available.
authors.affiliation: a Department of Immunology , Robert Debré Hospital, Reims University Hospitals , Reims , France.
authors.forename: Laure
authors.initials: L
authors.lastname: Zucchini
authors.affiliation: a Department of Immunology , Robert Debré Hospital, Reims University Hospitals , Reims , France.|b Faculty of Medicine , University of Reims Champagne-Ardenne , Reims , France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Giusti
authors.affiliation: a Department of Immunology , Robert Debré Hospital, Reims University Hospitals , Reims , France.
authors.forename: Grégory
authors.initials: G
authors.lastname: Gatouillat
authors.affiliation: c Department of Internal Medicine , Infectious Diseases, Clinical Immunology, Robert Debré Hospital, Reims University Hospitals , Reims , France , and.
authors.forename: Amélie
authors.initials: A
authors.lastname: Servettaz
authors.affiliation: a Department of Immunology , Robert Debré Hospital, Reims University Hospitals , Reims , France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Tabary
authors.affiliation: d Clinical Research Unit, Reims University Hospitals , Reims , France.
authors.forename: Coralie
authors.initials: C
authors.lastname: Barbe
authors.affiliation: a Department of Immunology , Robert Debré Hospital, Reims University Hospitals , Reims , France.|b Faculty of Medicine , University of Reims Champagne-Ardenne , Reims , France.
authors.forename: Bach-Nga
authors.initials: BN
authors.lastname: Pham
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology; D015415:Biomarkers; D001706:Biopsy; D002446:Celiac Disease / Q000097:blood* / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D005260:Female; D019204:GTP-Binding Proteins / Q000276:immunology; D005903:Gliadin / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D011503:Transglutaminases / Q000276:immunology; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D015415:Biomarkers; D007070:Immunoglobulin A; D007074:Immunoglobulin G; C000717608:TGM2 protein, human; D005903:Gliadin; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins
keywords: Deamidated gliadin peptides; anti-endomysium antibodies; anti-tissue transglutaminase antibodies; autoantibodies; duodenal biopsies