(A) Plasma spontaneous amidase activity and (B) proenzyme activation in healthy controls (HC, n = 303), patients with HAE I-II (n = 250), AAE (n = 20), HAE-nC1INH carriers of F12 mutations (F12c, n = 60) or non-carriers (F12nc, n = 268), patients suffering from IgE-mediated angioedema (IgE-AE, n = 64), non-allergic idiopathic histamine-dependent angioedema (HD-AE, n = 62) or chronic inflammatory diseases (Inflammatory, n = 23). Graph labels are identical for panel A and B. ns, not significant; ***, P<0.001; **, P<0.01 vs healthy control group. Box-whisker plots show the median (horizontal bars within boxes), the interquartile range (boxes) and the 5th to 95th centiles (vertical bars).