Hereditary angioedema with normal C1 inhibitor function: consensus of an international expert panel.

A new form of hereditary angioedema (HAE) with normal C1 inhibitor (C1INH) was first described in 2000. The lack of clear diagnostic criteria, the heterogeneity among affected patients, and the varying names given to this disease have led to substantial confusion among both physicians and patients. This study was designed to bring more clarity to the diagnosis and potential treatment of HAE with normal C1INH. An international symposium of experts was convened to review the field and develop consensus opinions that could help clinicians who evaluate and manage these patients. Criteria were developed for the diagnosis of HAE with normal C1INH in patients with recurrent angioedema in the absence of concurrent urticaria. In addition, potential therapeutic strategies are discussed. The consensus criteria developed during this symposium will allow physicians to better diagnose and treat patients with HAE with normal C1INH.