title: Identification of a serum transglutaminase threshold value for the noninvasive diagnosis of symptomatic adult celiac disease patients: a retrospective study.
abstract: BACKGROUND
  A celiac disease (CD) diagnosis is based on duodenal histology, with the exception of children showing anti-tissue transglutaminase (anti-tTG) serum levels exceeding ten times the cut-off. Our aim was to reproduce this simplified approach in adults, identifying an anti-tTG threshold value useful to diagnose CD without endoscopic procedures.
  
  
  METHODS
  A total of 671 adult CD patients were subjected to blood sampling to determine anti-tTG serum levels, as well as to endoscopy with biopsy to perform duodenal histology. The anti-tTG serum levels/cut-off ratio was compared with the degree of duodenal lesions.
  
  
  RESULTS
  Anti-tTG serum levels/cut-off ratio determined in patients with type IIIc was significantly higher than that measured in patients with type IIIb (p < 0.001), IIIa (p < 0.001), II (p < 0.05) and 0 (p < 0.001) of Marsh-Oberhuber histological classification. A significant correlation (r = 0.297, p < 0.0001) was found between the anti-tTG serum levels/cut-off ratio and the degree of duodenal lesions. The anti-tTG serum levels/cut-off ratio was classified as an accurate parameter (AUC = 0.715, p < 0.0001), with the best diagnostic performance obtained considering the threshold value >3.6 (sensitivity = 76.8 %, PPV = 97.2 %).
  
  
  CONCLUSIONS
  The anti-tTG serum levels/cut-off ratio correlates with the degree of duodenal lesions and, if used with the threshold value >3.6, could avoid endoscopy with biopsy in about 75 % of seropositive adults waiting for CD diagnosis. However, since this procedure could also imply CD diagnosis in almost 3 % of seropositive patients with normal villous architecture, a consensus opinion is needed to suggest its use in the diagnosis of adult CD.
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Di Tola
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Mariacatia
authors.initials: M
authors.lastname: Marino
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.|Klinikum Augsburg, Augsburg, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Goetze
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Casale
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Di Nardi
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Borghini
authors.affiliation: Department of Clinical Medicine, Sapienza University, Rome, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Donato
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Tiberti
authors.affiliation: Department of Internal Medicine and Medical Specialties, Sapienza University, Polyclinic Umberto I, Viale del Policlinico, 155, 00161, Rome, Italy. antonio.picarelli@uniroma1.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Picarelli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D002446:Celiac Disease / Q000175:diagnosis* / Q000473:pathology; D004384:Duodenoscopy; D004386:Duodenum / Q000473:pathology; D005260:Female; D006650:Histocompatibility Testing / Q000379:methods; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D011503:Transglutaminases / Q000276:immunology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D007070:Immunoglobulin A; D011503:Transglutaminases
keywords: Adult celiac disease; Anti-transglutaminase; Diagnosis; Duodenal lesions; Threshold value