A sensitive and specific assay to characterize plasma kallikrein activity in plasma from patients with hereditary angioedema

We developed a specific PKa assay that can detect low levels of PKa activity in plasma and can differentiate patients with HAE-C1INH from controls without HAE with high sensitivity and specificity. Using this assay, we demonstrated that sPKa activity is elevated during the intercritical period in patients with HAE-C1INH and in those with HAE-nC1INH compared with controls when measured after 6 h of cold incubation. This sensitive and specific PKa assay could be useful to characterize PKa activity in plasma samples from patients with HAE and could potentially serve as a future candidate biomarker for HAE-nC1INH.