Angiotensin-converting enzyme inhibitor-induced angioedema worsened with fresh frozen plasma

Fresh frozen plasma (FFP) has been used as an intervention for hereditary angioedema and for angioedema induced by the use of angiotensin-converting enzyme inhibitors. The mediator for both types of attacks is believed to be bradykinin. FFP would seem a reasonable treatment because it contains enzymes that break down bradykinin; however, it also contains high-molecular-weight kininogen and kallikrein, the substrates required to form it. To balance case reports describing the resolution of angiotensin-converting enzyme inhibitorinduced angioedema after administration of FFP, we describe the worsening of angioedema after its administration to a 68-year-old man who had been taking lisinopril for a year.