Effect of Intravenous Immunoglobulin in Chronic Urticaria with Increased Basophil CD203c Expression

We examined the effect of intravenous immunoglobulin (IVIg) in patients with increased basophil CD203c expression. In two patients, we followed the level of basophil CD203c expression by donor basophils exposed to the patient sera (normal range 0-5%) throughout treatment. Three patients with chronic urticaria with evidence of anti-IgE or FcɛRI autoantibodies who failed antihistamines, leukotriene modifier drugs, hydroxychloroquine, sulfasalazine, dapsone, colchicine, and cyclosporine (CsA) were treated with a single course of IVIg. One was treated with standard-dose IVIg 400 mg/kg/day for 4 days and two were treated with high-dose IVIg 1 gm/kg/day for 4 days. All three patients showed a response to IVIg. One patient improved after high-dose IVIg but relapsed in eight weeks. Her basophil CD203c expression was high prior to IVIg and CsA (28.6%), was low while on CsA prior to IVIg (2.6%), remained low immediately after IVIg (3.8%), and then increased when she relapsed (10.5%). The other two patients had sustained responses. One patient has remained hive-free for three years; his basophil CD203c expression was 47.9% before IVIg and has not been rechecked. The other patient remained in remission for eight months and continues to do well. Her basophil CD203c expression was 19.9% and 21.4% on two occasions prior to IVIg and normalized to 3.4% after IVIg. IVIg remains a viable alternative in patients with persistent urticaria with evidence of increased basophil CD203c expression unresponsive to first line therapies. In the two patients we examined closely, expression of basophil CD203c after IVIg correlated with their clinical condition.