ACE and hereditary angioedema: Methods: We enrolled patients with different types of AE including: AE-BK (confirmed hereditary angioedema (HAE) due to C1-inhibitor deficiency, patients with F12 gene mutations and acquired C1-INH deficiency AE, AE-MC, AE-DI (due to angiotensin converting enzyme-ACEi and to rTPA) and Chronic Spontaneous Urticaria with AE (CSU-AE) as control group.