title: Assessment of a combination screening assay for celiac disease.
abstract: OBJECTIVE
  A serological screening assay for celiac disease (CD), designed to simultaneously detect IgA and IgG anti-tissue transglutaminase (a-tTG) and IgA and IgG deamidated gliadin peptide antibodies (a-DGP), was recently developed. In this study, we establish the performance of this assay.
  
  
  METHODS
  We enrolled 41 CD patients and 18 CD patients on gluten-free diets. The diagnosis of CD was based on histological and serological criteria, including concomitant positive serology tests (a-tTG, IgA anti-endomysial antibodies). As control population, we enrolled 169 subjects: 145 disease controls and 24 blood donors. In all cases, serum samples were tested for: IgA a-tTG, IgG a-tTG, IgA a-DGP, IgG a-DGP, IgA anti-endomysial antibodies (EMA), IgA and IgG for a-tTG and a-DGP in a single assay.
  
  
  RESULTS
  The new test, QUANTA Lite (™) h-tTG/DGP Screen, detects all IgA and IgG antibodies against atTG and a-DGP present in a sample. In our study, the test showed 100% sensitivity and 91.12% specificity.
  
  
  CONCLUSIONS
  This study showed additional value of the new h-tTG/DGP Screen assay, which proved superior to more conventional assays and can be considered the best initial test for CD. Further studies are necessary to determine whether combination of h-tTG/DGP Screen with IgA a-tTG or IgA a-DGP can be used to obviate the need for duodenal biopsy in high- and low-risk populations.
authors.affiliation: University of Siena, Polo Scientifico di San Miniato Via Alcide Dè Gasperi 2, 53100 Siena, Italy.
authors.forename: Brunetta
authors.initials: B
authors.lastname: Porcelli
authors.affiliation: Department of Human Pathology and Oncology, University of Siena, Siena, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Ferretti
authors.affiliation: Pathological Anatomy, Siena University Hospital, Siena, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Vindigni
authors.affiliation: Clinical Pathology Laboratory, Siena University Hospital, Siena, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Scapellaato
authors.affiliation: University of Siena, Polo Scientifico di San Miniato Via Alcide Dè Gasperi 2, 53100 Siena, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Terzuoli
keywords: Anti-tissue transglutaminase antibodies; Celiac disease; Deamidated gliadin peptide antibodies; Diagnosis; Serological screening assay