Hereditary angioedema: a Chinese perspective

Hereditary angioedema (HAE) is a rare autosomal dominant disorder of vascular permeability associated with heterogeneous clinical manifestations, with prevalence estimated at 1/50,000. Most disease-causing variants lie within the SERPING1 gene, while FXII12, PLG and ANGPT1 gene variants are also reported to associate with HAE. Research on HAE in China began in the 1980s, and later studies identified some clinical characteristics of Chinese HAE patients that differ from the western population. Type 1 HAE (98.73%) accounts for the majority of Chinese HAE patients while no type 3 HAE patient has been diagnosed in China to date. Compared with other populations, the onset age (21.25 years) of Chinese HAE patients is older and the percentage of abdominal attacks (34.18%) is lower. A spectrum of mutations within SERPING1 has been established and a total of 56 mutations have been reported among Chinese patients. Currently, there is no approved drug for acute attacks on the Chinese market, and the choices for long-term prophylaxis are limited to danazol and tranexamic acid. Danazol has demonstrated good efficacy and is tolerated in most Chinese patients, although it has some side effects, especially at the beginning of the treatment with higher doses. Oedematous attacks are effectively prevented with a dosage of <= 200 mg/day in 80% patients. This article provides a brief update of HAE and reviews the research progress in the Chinese population within the past 30 years.