Background: Our knowledge of autoimmune characteristics of chronic idiopathic urticaria (CIU) is limited.
Objective: To study the demographic, laboratory, and clinical patterns of a cohort of patients with CIU.
Methods: We evaluated 236 patients with CIU seen in a recent 2-year span. For serum basophil activation testing (BAT-CD203), the samples were sent to the National Jewish Medical and Research Center for donor basophil CD203 expression assay (5% cell surface expression was considered a positive result).
Results: Of the 236 patients with CIU, 77% were females with a mean age of 39 years. The mean age of males was 43 years. Of patients tested for BAT-CD203 (50 females and 8 males), 38% of females (n = 19) and 13% of males (n = 1) had positive test results. Of the 146 females and 42 males tested for thyroid autoimmunity (TA), 34% of females (n = 50) and 17% of males (n = 7) had underlying TA. Nine BAT-CD203-positive females (47%) had TA compared with 11 of 30 BAT-CD203-negative females (37%). No correlation was found between antinuclear antibodies and BAT-CD203. Cyclosporine or corticosteroids were used in 28% of the study population, with another 16% requiring a trial of additional third-line agents with or without prednisone/cyclosporine. There was no significant difference in the maximum number of medications used in subgroups based on the presence or absence of BAT-CD203 and TA.
Conclusions: The frequency of TA in patients with CIU was 30%, which is higher than that previously reported. The frequency of TA and BAT-CD203 positivity was higher in females. In this clinical cohort, there was no correlation between BAT-CD203 and TA.