Successful Omalizumab Treatment of a 6-Year Old Child with Severe Solar Urticaria

S U N D A Y 410 Successful Omalizumab Treatment of a 6-Year Old Child with Severe Solar Urticaria Yuval Tal, MD, PhD, Zvi Dranitzki, MD, Meir Shalit, MD, FAAAAI, David Claes Enk, Assi Levi; Allergy and Clinical Immunology Unit, Department of Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel, Department of Dermatology, Hadassah Hebrew University Medical Center, Jerusalem, Israel, Photodermatosis Clinic, Laser unit, Department of Dermatology, Rabin Medical Center., Petah-Tikva, Israel. RATIONALE: Solar urticaria is a rare form of physical urticaria usually occurring minutes after sun exposure. Angioedema might accompany the urticaria in severe cases. Treatment is difficult and often unsatisfactory. Here, we present a 6-year old child with severe solar urticaria and angioedema following short exposures to light despite continued combination therapy with high dose anti-histamines and leukotriene-receptor antagonists. As the child faced living in darkness unless an effective therapeutic remedy was found, we initiated omalizumab treatment with cautious dose elevation. METHODS: Action spectrum and minimal urticaria dose (MUD) were established by UVB (290-320 nm), UVA1 (340-400 nm) and visible light (400-760 nm) photoprovocation tests. Omalizumab treatment was initiated, with dose elevation every two weeks up to a complete remission dose of 300 mg, repeated every four weeks as maintenance. RESULTS: The action spectrum was established within the visible light spectrum with a MUD of 30 J/cm (unchanged, preceding and during nonbiological therapy). Omalizumab treatment was added, beginning with a dose of 75 mg. Partial response was noted at a dose of 150 mg, with some recurrence prior to the next dosing. At a maintenance dose of 300 mg every four weeks, the child remains in remission one year after initiation of treatment, with no urticaria episodes even following prolonged exposure to mid-day summer sun. Repeated photoprovocation with visible light was negative, validating the clinical remission. CONCLUSIONS: Solar urticaria and angioedema are both agonizing and life-threatening conditions. Treatment with omalizumab should be considered when high dose antihistamines and leukotriene-receptor antagonists fail.