Plasma levels of cleaved high molecular weight kininogen (HK) in 30 normal subjects (□), in 19 patients with HAE during remission (R), in five patients with HAE during AA (type I = ○; type II = •) and in six patients with AAE. AAE patients (individuals identified by different symbols) were observed during R and three of them also during seven episodes of AA. Horizontal lines represent medians. In HAE, cleaved HK is normal during remission and significantly increased during attacks, while it is increased in AAE during both remission and attacks. Immunoblots of HK forms illustrating the profiles for each group are presented at the bottom of the figure.