Long-term hyposensitization and adverse immunologic responses. A laboratory evaluation.

Ninety atopic patients with allergic asthma and/or rhinitis were classified into three groups: group A, consisting of 30 patients never subjected to immunotherapy; group B, 30 patients receiving immunotherapy for various allergies for 3 to 24 months; group C, 30 patients receiving immunotherapy for 5 or more years. The following studies were performed using standard techniques: quantitative determination of serum immunoglobulin concentrations IgA, IgG, IgM, rheumatoid factor, C3 and C4 concentrations, antinuclear antibodies (ANA). Circulating immune complexes were detected by a competitive immuno-enzyme assay. No statistical differences were found in the groups studied for every parameter considered. Although signs and symptoms of autoimmune disease were not present, an elevated incidence of ANA in the entire group (23.3%) was found.