Coeliac disease: screened by a new strategy

Area of Science:

• Gastroenterology
• Immunology
• Clinical Diagnostics

Background:

• Coeliac disease prevalence varies across Europe.
• Accurate diagnostic tools are crucial for identifying coeliac disease.
• Antigliadin antibodies (AGA) have been used for screening, but their efficacy is debated.

Purpose of the Study:

• To determine the true prevalence of coeliac disease in Northern Italy.
• To compare the diagnostic accuracy of antigliadin antibodies (AGA) and endomysial antibodies (EmA) using a novel umbilical cord test.
• To evaluate the positive predictive value of different antibody tests for coeliac disease.

Main Methods:

• Serological screening of 4615 healthy adults in Northern Italy using AGA and EmA tests.
• Utilized a novel umbilical cord test for EmA detection.
• Performed small-intestine biopsies for histological confirmation in antibody-positive individuals.
• Analyzed T-cell receptor distributions in intraepithelial lymphocytes.

Main Results:

• Identified a higher-than-expected prevalence of coeliac disease: 163/100,000 in the Italian group and 216/100,000 in the German group.
• The umbilical cord EmA test demonstrated 100% positive predictive value when confirmed by biopsy.
• AGA IgG, AGA IgA, and combined AGA IgA/IgG showed significantly lower positive predictive values (2%, 12%, and 33%, respectively).
• Patients positive for AGA but negative for EmA exhibited normal small-intestine histology.

Conclusions:

• Antigliadin antibodies are not ideal for coeliac disease screening due to low specificity and predictive value.
• The umbilical cord EmA test is a superior diagnostic tool, offering high sensitivity, specificity, and positive predictive value.
• The EmA test is cost-effective and recommended for accurate coeliac disease screening.