Chronic idiopathic urticaria ; Anti-Fc e RI a antibody ; Autologous serum skin test
Abstract
The pathogenesis of chronic idiopathic urticaria is not completely understood, but mast cell degranulation and histamine release are thought to be of central importance. It is now established that circulating autoantibodies against the high-affinity IgE receptor (Fc ε RI α ) can be found approximately one third of patients with chronic idiopathic urticaria. These autoantibodies can be detected by in vivo autologous serum skin test and by in vitro basophil and mast cell histamine release assays as functional tests, and also can be confirmed by in vitro enzyme-linked immunosorbent assay to Fc ε RI α and Western blot analysis. Our purpose was to determine the proportion of patients with positive autologous serum skin test and anti-Fc ε RI α antibody in chronic idiopathic urticaria and whether there are differences between patients with and those without autoantibodies in the clinical features. Results are as follows: 1. Positive result to autologous serum skin test was 58.5% in 41 patients of chronic idiopathic urticaria. There was no significant difference of clinical features and laboratory tests between patients with positive skin test and those with negative results. 2. By enzyme-linked immunosorbent assay, anti-Fc ε RI α antibody was detected in sera from 34% of patients with chronic idiopathic urticaria. 3. In sera from 33% of patients with positive skin test and 35% of those with negative result, we could demonstrate anti-Fc ε RI α antibody by enzyme-linked immunosorbent assay. 4. There was no differences of clinical features and laboratory tests between the patients with autoantibodies to Fc ε RI α and those without, except female predominance and longer urticaria history in those with autoantibodies.
Our results demonstrated anti-Fc ε RI α antibody in the sera of chronic idiopathic urticaria patients, but there was no differences of clinical features and laboratory tests between the patients with autoantibodies to Fc ε RI α and those without. And we could not demonstrate the correlation between autologous serum skin test and the occurrence of anti-Fc ε RI α antibody.