title: Screening of the adult population in Iran for coeliac disease: comparison of the tissue-transglutaminase antibody and anti-endomysial antibody tests.
abstract: OBJECTIVE
  Population-based studies for the prevalence of coeliac disease (CD) in west-Asian countries are scarce. We aimed to determine the prevalence of gluten-sensitive enteropathy (GSE) in the general population of northern and southern Iran, and evaluate the sensitivity and specificity of the anti-endomysial antibody (EMA) immunofluorescent test and the enzyme-linked immunosorbent assay-based test for determination of the IgA anti-tissue transglutaminase antibody (tTG-Ab) using the human recombinant transglutaminase antigen for the detection of CD in screening the asymptomatic adult population.
  
  
  METHODS
  Using a stratified random sampling method we enrolled a total of 2799 individuals (1438 from Sari and 1361 from Kerman). The mean age was 33.7 years (range 18-66), with 1398 men. IgA anti-tissue transglutaminase (tTG) and IgA anti-EMA were determined in the serum of all subjects. Those participants with a positive serology for any of the two tests underwent small intestinal biopsy, and were classified according to revised Marsh criteria histologically. A diagnosis of GSE was based on positive serology and a compatible histopathological finding. The maximum likelihood latent class model was used to estimate the sensitivity and specificity of the two tests.
  
  
  RESULTS
  Twenty-nine cases showed positive IgA tTG-Ab (15 men and 14 women, mean age 35.4 years, range 18-59), whereas only five were simultaneously positive for EMA. Except for two subjects with normal small bowel histology (Marsh 0), all other subjects were found to have biopsy findings compatible with GSE: 18 Marsh I, five Marsh II, three Marsh IIIa and one Marsh IIIc lesions. he prevalence of GSE was 0.96% or 1:104. The sensitivity and specificity of the human-recombinant IgA tTG-Ab assay were 100 and 99%, respectively, whereas the results for IgA EMA were 19 and 100%, respectively. The IgA EMA was positive in cases with advanced mucosal lesions of the small bowel. The mean serum value of IgA tTG-Ab was higher in patients with severe enteropathy compared with those showing slight mucosal changes (P<0.05).
  
  
  CONCLUSIONS
  The minimum prevalence of gluten sensitivity among the general population of northern and southern Iran is 1:104. The best screening test for the detection of GSE in the general population is IgA tTG-Ab.
authors.affiliation: Digestive Disease Research Centre, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Akbari
authors.forename: Ashraf
authors.initials: A
authors.lastname: Mohammadkhani
authors.forename: Hafez
authors.initials: H
authors.lastname: Fakheri
authors.forename: Mohammad
authors.initials: M
authors.lastname: Javad Zahedi
authors.forename: Bijan
authors.initials: B
authors.lastname: Shahbazkhani
authors.forename: Mehdi
authors.initials: M
authors.lastname: Nouraie
authors.forename: Masoud
authors.initials: M
authors.lastname: Sotoudeh
authors.forename: Ramin
authors.initials: R
authors.lastname: Shakeri
authors.forename: Reza
authors.initials: R
authors.lastname: Malekzadeh
mesh_terms: D000328:Adult; D000368:Aged; D000906:Antibodies / Q000097:blood; D001323:Autoantibodies / Q000097:blood; D002446:Celiac Disease / Q000175:diagnosis / Q000453:epidemiology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D019204:GTP-Binding Proteins / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D007492:Iran / Q000453:epidemiology; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D015995:Prevalence; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D012680:Sensitivity and Specificity; D012698:Serologic Tests; D011503:Transglutaminases / Q000276:immunology; D014908:Triticum
chemical_list: D000906:Antibodies; D001323:Autoantibodies; D007070:Immunoglobulin A; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins