Increased allergic sensitization to mugwort in chronic urticaria.

BACKGROUND

Mugwort pollen is known to cross-react with a variety of spices and vegetables that are typically part of elimination diets used in the treatment of chronic urticaria (CU).

OBJECTIVE

We sought to investigate the association between CU and allergic sensitization to mugwort pollen.

METHODS

We conducted 2 case-control studies comparing aeroallergen skin prick test results between patients with and without CU and with or without allergic rhinitis (total n = 202).

RESULTS

CU patients with coexisting allergic rhinitis were more than twice as likely to be sensitized to mugwort as subjects not suffering from CU (67 vs. 30%; p = 0.004). Ragweed, cat, rat and mite sensitization were also significantly associated with CU. Overall, patients with CU had more positive aeroallergen skin tests than patients without CU (p < 0.005).

CONCLUSION

Mugwort sensitization was associated with CU, possibly contributing to beneficial effect of elimination diets.