The effectiveness of low-dose intravenous immunoglobulin in chronic urticaria.

Sir, Recently, positive effects of high-dose intravenous immunoglobulin (IVIG) (2 g/kg body weight) have been observed in immune thrombocytopenic purpura (ITP) (1, 2) as well as in autoimmune blistering diseases (3). Furthermore, successful treatments of autoimmune chronic urticaria with high-dose IVIG was reported (4). Herein, we describe a very bene®cial effect in a patient with a long-standing chronic urticaria tested negatively in a skin test with autologous serum. Since positive effects in pemphigus foliaceus (5) had been observed recently using a reduced dosage of IVIG, a low-dose treatment seemed preferable in this patient. A 63-year-old woman presented at our department with a 2-year history of chronic urticaria previously treated with antihistamines, dapson, antibiotics and antimycotics in several departments of dermatology and allergology centres. At admittance, the patient was treated with a combination of H1 and H2 antihistamines. Despite this medication, 5 to 10 urticae, sized up to 10 cm in diameter, occurred 4 times/week indicating an urticaria score (4) of 8. We continued the antihistamine treatment and started an additional therapy with IVIG 0.2 g/kg body mass over 1 day with the readministration of IVIG after 4 weeks. After the ®rst application of IVIG, the urticaria score could be reduced to 1. At the time of re-administration, only a single lesion of about 1 cm in diameter was present. Finally, the urticaria score could be suppressed to 1 by repeated administrations of IVIG in intervals of 4 weeks. Therefore, IVIG at a low-dosage may also counteract in the familiar way with the immune system via Fc receptor blockade, anti-idiotypic antibodies and modulation of cytokines (6, 7). In our opinion, this case clearly indicates that the administration of IVIG might be effective in suppressing antihistamine resistant chronic urticaria. Furthermore, this effect can also be observed at the lower dose of 0.2 g/kg body mass, which has the considerable advantage of decreasing costs as well as a reduced risk of side effects.