Oral iron therapy and chronic idiopathic urticaria: sideropenic urticaria?

Chronic urticaria (CU) is frequent, remains often idiopathic despite diagnostic efforts, and sometimes poorly responds to oral antihistamines and/or corticosteroids. We noticed that hyposideremia is often found in patients with chronic idiopathic urticaria poorly responsive to usual treatments (prCIU), and oral iron therapy is frequently associated to improvement or resolution of urticaria. Between 2003 and 2012, we observed 122 patients with prCIU, of which 81 had moderate hyposideremia at our first visit. They continued the antihistamines already practiced and received oral iron therapy for 30 or 45 days. Two months after our first visit, all had normal serum iron levels; 64 reported complete remission of urticaria and 17 reported improvement superior to 80%. No adverse reactions to treatment were observed. Follow-up visits confirmed stability of results over 6 months. Our preliminary data show that hyposideremia is the only abnormality in many patients with prCIU, and restoration of normal iron serum levels is associated to remission or remarkable clinical improvement of urticaria. In consideration of low cost and potential benefits for some patients, determination of serum levels of iron could be introduced in the diagnostic workup of chronic urticaria, maybe as a second-level exam in patients without other relevant clinical or laboratory abnormalities.