title: High rate of positive anti-tissue transglutaminase antibodies in chronic liver disease. Role of liver decompensation and of the antigen source.
abstract: BACKGROUND
  Since the recognition of tissue transglutaminase (tTG) as the target antigen of anti-endomysium antibodies, several ELISA assays using either guinea pig or human recombinant tTG have been developed. The aim of the study was to compare the behaviour of anti-tTG and anti-endomysium antibodies assays in coeliacs and in patients with chronic liver disease.
  
  
  METHODS
  34 patients (24 women, 34.9 +/- 12.5 years) with coeliac disease and 41 with chronic liver disease (14 women, 57 +/- 11.2 years), including 19 cirrhotics, were evaluated for anti-endomysium antibodies by indirect immunofluorescence and for anti-tTG IgA antibodies by ELISA, using guinea pig liver or human recombinant transglutaminase.
  
  
  RESULTS
  The prevalences of anti-tTG and anti-endomysium antibodies were 100% in patients with coeliac disease at diagnosis, 75% and 64.3% in patients on a gluten-free diet. All liver disease patients were negative for anti-endomysium antibodies, while 11 (26.8%) were positive for anti-tTG. All these patients had liver cirrhosis and represented 57.9% of all cirrhotics. The presence of anti-tTG was associated with higher Child-Pugh scores. The use of human transglutaminase determined a reduction in the rate of positive results; however, the rate of positive anti-tTG was still 17.1% in all liver disease patients and 31.6% in cirrhotics.
  
  
  CONCLUSIONS
  Our data confirm that anti-tTG have a similar sensitivity compared with anti-endomysium antibodies assay in coeliacs. However, a high prevalence of positive anti-tTG results is observed in cirrhotic patients, even when human recombinant tTG is used. The high prevalence of positive results among cirrhotic patients is associated with more advanced liver disease.
authors.affiliation: Gastroenterology Unit, Dept. of Internal Medicine and Liver Unit, IRCCS Policlinico Hospital and University of Milan, Italy. mvecchi@policlinico.mi.it
authors.forename: M
authors.initials: M
authors.lastname: Vecchi
authors.forename: C
authors.initials: C
authors.lastname: Folli
authors.forename: M F
authors.initials: MF
authors.lastname: Donato
authors.forename: S
authors.initials: S
authors.lastname: Formenti
authors.forename: E
authors.initials: E
authors.lastname: Arosio
authors.forename: R
authors.initials: R
authors.lastname: de Franchis
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000032:analysis; D002446:Celiac Disease / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006521:Hepatitis, Chronic / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D008103:Liver Cirrhosis / Q000276:immunology; D008107:Liver Diseases / Q000276:immunology*; D017093:Liver Failure / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D011503:Transglutaminases / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D007070:Immunoglobulin A; D011503:Transglutaminases