Autoimmune polyendocrine syndrome type 2 in patient with severe allergic asthma treated with omalizumab.

Asthma therapy with monoclonal antibodies is a promising and effective approach for those with a severe and refractory type of disease. Although such a targeted therapy is considered to be safe, unusual complications may occur. We present a case of a 45 year-old female patient with severe allergic asthma and chronic spontaneous urticaria, who developed autoimmune polyendocrine syndrome type 2 (APS-2) after 26 months of omalizumab administration. The patient was diagnosed with primary adrenal insufficiency (Addison's disease) and Hashimoto's thyroiditis accompanied by autoimmune atrophic gastritis. According to our knowledge this is the first description of APS-2 that developed in conjunction with omalizumab treatment, although we have no evidence that the observed phenomenon indicated a cause-effect relationship to omalizumab.