Hereditary Angioedema with Normal C1 Inhibitor and F12 Mutations in 42 Brazilian Families

Our study included a large number of patients with FXII-HAE, and, as the first such study conducted in a South American population, it highlighted significant differences between this and other study populations. The high number of symptomatic males and patients with estrogen-independent FXII-HAE found here suggests that male sex and the absence of a hormonal influence should not discourage clinicians from searching for F12 mutations in cases of HAE with normal C1-INH.