[Autoantibodies in relatives of IgA-deficient patients]

Selective IgA deficiency is frequently associated with autoimmune phenomena. We addressed the question, whether autoantibodies are more frequent in relatives of IgA deficient persons. Fifteen first-degree relatives of patients with a familial form of IgA deficiency and 129 first-degree relatives of patients with a sporadic form of IgA deficiency were evaluated. Following autoantibodies were detected: antinuclear, anti-thyreoglobulin, anti-thyroid microsomal, anti-gastric parietal cell, anti-reticulin, anti-smooth muscle, anti-mitochondrial, anti-neutrophil cytoplasmatic, anti-cardiolipin, rheumatoid factor and antibodies against gliadin. We did not find increase in any of the autoantibodies evaluated in any groups of patients. Our results do not support a significant genetic influence in autoantibodies formation in selective IgA deficiency.