Presented at the 13th International Congress on Autoimmunity in Athens, Greece

Speaker: Aaron Lerner

Key Takeaways:

The guidelines for the diagnosis of celiac disease (CD) recommend using CD serology for the screening and diagnosing of CD.

  • Serologic tests for CD currently include:
    • tissue transglutaminase (tTG) immunoglobulin A (IgA) and tTG immunoglobulin G (IgG) tests
      • tTG-IgA were recommended as serological “gold standard”
      • limitations: normal range levels not well defined, manufacturer’s cut-off levels are extremely variable, insufficient standardization
    • endomysial antibody (EMA) -IgA test
      • limitations: subjective, susceptible to interobservers’ variability (difference in the measurements between observers), expensive and time-consuming (immunofluorescence)
    • deamidated gliadin peptide (DGP) -IgA and DGP-IgG tests
      • losing their space in diagnosis
      • limitations: poor positive predictive value in children with CD (especially in IgA sufficient individuals), and no effective differentiation between individuals with and without CD.

The current standard of classical serological markers for the diagnosis of CD has its limitations. Therefore, a new generation of markers should be considered and developed.

Summary:

83% of Americans who have CD are undiagnosed or misdiagnosed with other conditions. Late diagnosis has long-term complications: short stature, osteoporosis, enamel defects, nutritional deficiencies, cancer predisposition, and susceptibility to other autoimmune diseases. Lerner proposed that the tTG neo-epitope should be considered as a new diagnostic marker for CD.

The tTG neo-epitope has:

  • superior performance as a screening assay
  • high sensitivity and specificity in the pediatric population
  • very good correlation with Marsh criteria (classification system used to describe the stages of damage in the small intestine as seen under a microscope – ranged from 0 to 4, with a type of 3 indicating CD)
  • early marker for silent or latent CD