Immunoglobulin A deficiency in celiac disease

Area of Science:

• Immunology
• Gastroenterology
• Celiac Disease Research

Background:

• Selective IgA deficiency is the most common primary immunodeficiency.
• It occurs more frequently in individuals with celiac disease (CD).
• Previous studies have not extensively examined IgA deficiency and partial deficiency in US CD patients.

Purpose of the Study:

• To determine the prevalence of immunoglobulin A (IgA) deficiency and partial deficiency in celiac disease (CD) patients.
• To assess the clinical significance of these deficiencies in CD patients.

Main Methods:

• Retrospective cohort study.
• Involved 1498 adults and 317 children diagnosed with CD at a University Medical Center.
• Analyzed IgA levels and associated autoimmune conditions.

Main Results:

• Prevalence of IgA deficiency/partial deficiency was 2.1% in adults and 1.9% in children with CD.
• Adults with CD and IgA deficiency/partial deficiency showed a higher rate of concomitant autoimmune disease (29%) compared to those with normal IgA levels (12%).
• IgA-deficient patients with persistently positive IgG celiac serologies despite a gluten-free diet had normal repeat biopsies, with positive IgG tissue transglutaminase and antigliadin antibodies.

Conclusions:

• Selective IgA deficiency/partial deficiency is found in approximately 2% of CD patients at this center, affecting adults and children equally.
• Adult CD patients with IgA deficiency/partial deficiency exhibit a greater prevalence of associated autoimmune diseases.
• In IgA-deficient individuals, elevated IgG celiac serologies may persist even with histological improvement on a gluten-free diet.