Novel screening assay performance in pediatric celiac disease and adult dermatitis herpetiformis

Area of Science:

• Immunology
• Gastroenterology
• Diagnostic Assay Development

Background:

• Gluten-sensitive enteropathy (GSE), commonly known as celiac disease (CD), is diagnosed using serologic assays.
• Current diagnostic protocols often involve measuring total serum IgA alongside specific antibody tests.
• There is a need for improved screening assays that are both sensitive and specific for GSE.

Purpose of the Study:

• To evaluate the performance of a novel combined antigen-screening assay for gluten-sensitive enteropathy (GSE).
• To assess the sensitivity and specificity of a new IgA/IgG anti-tissue transglutaminase (tTG)/deamidated gliadin peptides (DGP) enzyme immunoassay (EIA) screen.
• To determine if this combined assay can replace the current recommendation of measuring total serum IgA.

Main Methods:

• Sera from 111 pediatric patients suspected of CD, 130 adults with dermatitis herpetiformis (DH), and 126 controls were analyzed.
• A novel IgA/IgG anti-tTG/DGP EIA screen was performed in a single test well.
• Individual marker and isotype assessments were conducted using separate EIAs for comparison.

Main Results:

• The IgA/IgG anti-tTG/DGP EIA screen demonstrated 92.6% sensitivity and 94.3% specificity in pediatric CD.
• The assay correctly identified one IgA-anti-tTG negative pediatric CD patient and all 10 IgA-deficient sera tested.
• For dermatitis herpetiformis (DH), the screen showed 65% sensitivity and 100% specificity (retrospective) and 62% sensitivity and 100% specificity (prospective).

Conclusions:

• The novel IgA/IgG anti-tTG/DGP EIA screen is a sensitive and specific diagnostic tool for GSE, particularly in pediatric CD.
• This combined screening assay performed comparably or slightly better than IgA anti-tTG alone in pediatric CD.
• The findings suggest this new assay could potentially eliminate the need for routine total serum IgA measurement in suspected GSE cases.