87 Treatment of Idiopathic Nonhistaminergic Angiodema with Icatibant

BACKGROUND: Patients with Idiopathic nonhistaminergic angioedema appear to have similar clinical features and pathogenesis as those with hereditary angioedema. Icatibant, a selective bradykinin β2 receptor antagonist, licensed for use in acute attacks of hereditary angioedema could be also effective in treating other forms of angioedema. We report a patient with idiopathic angioedema who was successfully treated with icatibant. METHODS: A 77-year-old man with a history of arterial hypertension currently treated with hydrochlorothiazide and type II diabetes under insulin treatment. He had suffered from recurrent angioedema attacks located on his tongue without urticaria during the last 7 years. Serum levels of C1-INH, C4 and C1q and C1-INH activity were normal. In spite of cessation of treatment with ACE inhibitors and RAAS-blockers (he had been treated with enalapril and losartan previously) he continued with the angioedema attacks. As no cause of angioedema could be identified and the angioedema did not response to antihistamines, the patient was diagnosed of idiopathic nonhistaminergic angioedema. In one of the episodes he was admitted at the emergency room with a swollen tongue. The edema gradually progressed in spite of the treatment with antihistamines, corticosteroids and epinephrine. Tracheotomy was considered due to the severity of the angioedema that began to cause airway compromise. After consulting the Allergy Unit, treatment with icatibant was administered. RESULTS: Approximately 30 minutes after the subcutaneous administration of icatibant 30 mg the symptoms improved and the angioedema resolved completely within 6 hours. The only adverse effect following the icatibant administration was pain localized in the injection site. After 5 months the patient suffered a similar attack that was also successfully treated with icatibant sc. CONCLUSIONS: Icatibant administered subcutaneously provided an effective and well-tolerated treatment option for acute angioedema attacks in a patient with idiopathic nonhistaminergic angioedema. This form of angioedema could have a pathogenic mechanism similar to the bradikinin mediated angioedema. We suggest the use of icatibant in the treatment of severe attacks of angioedema in patients that do not response to antihistamines, corticosteroids and epinephrine.