25 Jul
C1 inhibitor (C1-INH) is a multispecific protease inhibitor that regulates enzymes of the complement, coagulation, fibrinolytic, and kinin systems. A deficiency of functionally active C1-INH may lead to life-threatening angioedema. Two major forms of C1-INH deficiency are known; the congenital form hereditary angioedema (HAE), and the acquired form that is associated with a variety of conditions, including lymphoid malignancies. C1-INH functional assay is useful in diagnosis of hereditary angioedema and for monitoring response to therapy.