Improving patient outcomes in hereditary angioedema: reducing attack frequency using routine prevention with C1 inhibitor concentrate.

Hereditary angioedema (HAE) is a rare inherited disorder, characterised by recurrent oedema attacks in various regions of the body. In HAE, mutations in the C1 esterase inhibitor (C1-INH) gene result in decreased C1-INH concentrations (type I HAE) or functionally deficient C1-INH (type II HAE), leading to inappropriate activation of the kallikrein-kinin system and release of vasoactive mediators. Treatment of HAE aims to manage acute attacks (using replacement C1-INH or bradykinin B2 receptor antagonist) or prevent attacks through prophylaxis (using C1-INH or attenuated androgens). We present a case of a 67-year-old man with HAE who suffered a high number of breakthrough HAE attacks while undergoing long-term prophylaxis with attenuated androgens. Androgen therapy was safely discontinued and routine prevention therapy with C1-INH (1000 U) introduced as part of an individualised management approach, in line with published clinical trial data, which improved patient outcomes in terms of HAE attack frequency and severity. 2014 BMJ Publishing Group Ltd.