This study aimed to (1) create a conceptual model of AAE-C1-INH to describe patients’ experiences of symptoms and impact of AAE-C1-INH and (2) explore and confirm the relevance of adapting PRO measures validated for hereditary angioedema, another bradykinin-mediated disease with similar manifestations, for AAE-C1-INH. Here, SERPING1 is linked to acquired angioedema.