Antibodies against deamidated gliadin peptide (DGP) identifies adult celiac disease patients negative for antibodies against endomysium and tissue transglutaminase (tTG)

Charlotte Dahle (1) , Simone Ignatova (2) , Anne Hagman (1) , Magnus Ström (3)

1 Clinical immunology & transfusion medicine
2 Pathology
3 Gastroenterology

Purpose: To evaluate diagnostic utility of antibodies against deamidated gliadin peptide (DGP). Methods: Sera from 176 adults, referred for endoscopy without previous analysis of antibodies against tissue transglutaminase (tTG) or endomysium (EmA), were retrospectively analyzed by ELISAs detecting IgA/IgG-DGP or a mixture of DGP and tTG, and compared with IgA-tTG and EmA. Seventy-nine individuals were diagnosed with celiac disease (CD). Results: Receiver operating characteristic (ROC) analyses verified the manufacturers' cut-off limits except for IgA/IgG-DGP/tTG. In sera without IgA deficiency the sensitivity was higher for IgA/IgG-DGP (0.85-0.87) compared to IgA-tTg (0.76) and EmA (0.61). All tests showed high specificity (0.95-1.00). Eighteen CD-sera were negative regarding IgA-tTG, nine of which were positive for IgA/IgG-DGP. Sera from CD-patients >70 years were more often negative for IgA-tTG (50%) and IgA/IgG-DGP (36%) than younger patients (15% and 8% respectively) (p<0.01). Three of the four IgA-deficient patients were positive in the IgA/IgG-DGP assay. Conclusions: In this study of patients unselected regarding IgA-tTg/EmA, thus unbiased in this respect, IgA/IgG-DGP identified adult celiac disease patients negative for antibodies against endomysium and tissue transglutaminase. Serology is often negative in elderly patients with CD, a small bowel biopsy should therefore generously be performed before CD is excluded.

Mots clés: Medicine

Charlotte Dahle, Simone Ignatova, Anne Hagman, Magnus Ström. Antibodies against deamidated gliadin peptide (DGP) identifies adult celiac disease patients negative for antibodies against endomysium and tissue transglutaminase (tTG). Alimentary Pharmacology and Therapeutics, 2010, 32 (2), pp.254. ⟨10.1111/j.1365-2036.2010.04337.x⟩. ⟨hal-00552566⟩