Clinical and genetic features of hereditary angioedema with and without C1‐inhibitor (C1‐INH) deficiency in Japan
Chinami Hashimura, Chikako Kiyohara, Jun‐ichi Fukushi, Tomoya Hirose, Isao Ohsawa, Tomoko Tahira, Takahiko Horiuchi
Abstract
To the Editor, Hereditary angioedema with normal C1-inhibitor (HAEnCI) is an umbrella term for several types of HAE that phenotypically resemble HAE but in which variants affecting function have been identified in genes other than the C1-INH gene (SERPING1). 1 In contrast to European patients with HAE, we suppose comprehensive clinical and genetic data of HAE are scarcely reported from Asian countries, including Japan. In particular, HAEnCI in Asia has not been clearly characterized. Considering ethnic differences, it would be important to clarify the features of HAE in the Asian population. Here, we report the clinical and genetic features of Japanese patients with 158 cases from 122 families with HAE-C1-INH and 21 cases from 21 families with HAEnCI. HAEnCI was defined as follows: normal C1-INH activity, no variants affecting function in the SERPING1 gene, at least one relative with recurrent angioedema attacks (i.e., positive family history), no history of urticaria, and lack of efficacy by antihistamines or corticosteroids. b Fisher's exact test.