While plasma kallikrein has a central role in HAE-1, HAE-2, and angioedema due to acquired C1-INH deficiency, the role of KLK-1 and cellular elements (leukocytes, platelets) has not been ruled out in the initiation of kinin-mediated vascular disorders. Here, SERPING1 is linked to hyperinsulinemic hypoglycemia, familial, 4.