title: Antibody levels in adult patients with coeliac disease during gluten-free diet: a rapid initial decrease of clinical importance.
abstract: OBJECTIVE
  Analysis of antibodies against tissue transglutaminase (tTG) has been shown valuable in the diagnosis of coeliac disease (CD) but how quickly serum titres decrease after introduction of a gluten-free diet (GFD) is not known in adults. CD is a well-recognized disorder amongst the general population and many persons try a GFD for fairly vague symptoms before they seek medical advice. Therefore, it is important to determine the time that the serologic tests remain predictive of the disease after the introduction of a GFD.
  
  
  METHODS
  Sera were taken from 22 consecutively biopsy-proven adult patients with CD in connection with the diagnostic biopsy. The patients were followed for 1 year and sera were taken after 1, 3, 6 and 12 months after start of a GFD. Sera were stored at -20 degrees C and analysed for IgA antibodies against gliadin, endomysium and two different commercial tTG assays based on recombinant human tTG (tTGrh) and guinea-pig liver (tTGgp).
  
  
  RESULTS
  Twenty patients could be followed during GFD and all antibody titres fell sharply within 1 month after introduction of a GFD and continued to decline during the survey interval. Thirty days after beginning the diet only 58, 84, 74 and 53% of all patients had positive antibody levels of tTGrh, tTGgp, EmA and AGA respectively.
  
  
  CONCLUSIONS
  As the antibodies used to confirm the diagnosis of CD fall rapidly and continue to decline following the introduction of a GFD, it is important that health care providers carefully inquire about the possibility of self-prescribed diets before patients sought medical attention.
authors.affiliation: Department of Medicine, KSS, Skövde, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Midhagen
authors.forename: A-K
authors.initials: AK
authors.lastname: Aberg
authors.forename: P
authors.initials: P
authors.lastname: Olcén
authors.forename: G
authors.initials: G
authors.lastname: Järnerot
authors.forename: T
authors.initials: T
authors.lastname: Valdimarsson
authors.forename: I
authors.initials: I
authors.lastname: Dahlbom
authors.forename: T
authors.initials: T
authors.lastname: Hansson
authors.forename: M
authors.initials: M
authors.lastname: Ström
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002446:Celiac Disease / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D018753:Diet, Protein-Restricted / Q000379:methods*; D005260:Female; D005983:Glutens / Q000008:administration & dosage; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011994:Recombinant Proteins / Q000097:blood; D013997:Time Factors; D011503:Transglutaminases / Q000276:immunology*
chemical_list: D007070:Immunoglobulin A; D011994:Recombinant Proteins; D005983:Glutens; D011503:Transglutaminases