Abstract
Bradykinin concentrations and the ratio of bradykinin to its stable metabolite BK1–5 (RPPGF) were significantly increased in patients presenting with angiotensin-converting enzyme (ACE) inhibitor-associated angioedema compared to ACE inhibitor-treated controls. Cleavage of high molecular weight kininogen was not increased in patients with ACE inhibitor-associated angioedema, indicating that increased bradykinin concentrations result from decreased degradation.