Solar urticaria unresponsive to intravenous immunoglobulins.

The treatment of solar urticaria (SU) can be difficult. Only a few cases of SU have been treated with intravenous immunoglobulins (IVIg) (as monotherapy or combined with phototherapy), with reported fast and durable increase of solar exposure tolerance. A 61-year-old female with severe UVB- and UVA-induced SU and a 62-year-old female with severe UVA and visible light-induced SU were both treated with a single course of IVIg (total dose of 2 g/kg), infused over 3 days. Phototest, performed 3 months after the treatment, showed only a slight minimal urticating dose improvement, and both patients reported just a moderate and 'transient' subjective improvement. Our patient's poorer response, compared with previous reports, may be due to differences in IVIg's treatment schedules, which are reviewed.