Clinical Evolution of Acute Urticaria and Association With IgE Autoantibodies.

BACKGROUND

Most patients with acute urticaria (AU) have remission of the disease (>80%) and some progress to chronic forms (<20%). The role of IgE autoallergy in this transition remains unclear.

OBJECTIVE

To investigate whether IgE autoantibodies (IgE-AA) against thyroperoxidase, eosinophil peroxidase, and eosinophil cationic protein were related with the progression of AU to chronic spontaneous urticaria (CSU).

METHODS

We conducted a prospective cohort study (Acute to Chronic Urticaria Time Evolution cohort), in which patients with AU were followed for 2 years. After the first 6 weeks, patients were classified into 2 groups according to the clinical evolution of the disease in AU-remission or CSU. IgE-AA against thyroperoxidase, eosinophil peroxidase, and eosinophil cationic protein were measured in both groups during the AU period, and then after 6, 12, and 24 months. As an exploratory analysis, allergenic activity was evaluated during the first 6 months of urticaria with basophil activation test.

RESULTS

After 6 weeks, 80.6% (n = 104) of patients from the Acute to Chronic Urticaria Time Evolution cohort achieved remission, whereas 19.3% (n = 25) progressed to CSU. At baseline, IgE-AA were higher in patients who developed CSU than in those who remitted (odds ratio, 3.2; 95% CI, 1.12-9.62; P = .05). After 2 years of follow-up, 52% of patients with CSU versus 15.3% of patients in AU-remission were IgE-AA positive. Basophil activation test showed higher basophil activation in the IgE-AA positive CSU group compared with the AU-remission group.

CONCLUSIONS

The presence of IgE-AA in patients with AU increases the probability of progression to CSU, suggesting their potential value as early biomarkers for predicting AU evolution.