title: Angioedema: etiology, pathophysiology, current and emerging therapies.
abstract: BACKGROUND
  Angioedema (AE) is characterized by nonpitting edema of the dermis and subcutaneous layers. The most common sites of involvement are the tongue, lips, face, and throat; however, swelling can also occur in the extremities, genitalia, and viscera. Life-threatening airway swelling can also occur. AE may be allergic or nonallergic. The overall lifetime incidence of AE is reported to be as high as 15%.
  
  
  OBJECTIVE
  This article summarizes the etiology, pathophysiology, and current treatment of several forms of nonallergic AE (including hereditary, acquired, and idiopathic AE) and focuses on angiotensin-converting enzyme inhibitor-induced angioedema (ACEi-AE), which is responsible for 30%-40% of all AE seen in United States emergency departments.
  
  
  CONCLUSIONS
  Although the triggers, which are primary biologic mechanisms, and treatments for ACEi-AE may differ from those of the hereditary and acquired forms of AE, the clinical effects of ACEi-AE are mediated through a shared pathway, the kallikrein-kinin system. Thus, although current therapeutic options for ACEi-AE are limited, recent advances in the treatment of hereditary AE (HAE) appear promising for improving the outcomes of patients with ACEi-AE.
  
  
  CONCLUSIONS
  New HAE medications that correct imbalances in the kallikrein-kinin system may prove safe and efficacious in the treatment of ACEi-AE.
authors.affiliation: Division of Emergency Medicine, Washington University School of Medicine, St Louis, Missouri.
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Lewis
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000799:Angioedema / Q000145:classification / Q000453:epidemiology / Q000209:etiology / Q000628:therapy; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects*; D001920:Bradykinin / Q000031:analogs & derivatives / Q000627:therapeutic use; D050718:Complement C1 Inhibitor Protein / Q000627:therapeutic use; D004724:Endoscopy; D006801:Humans; D015994:Incidence; D007442:Intubation, Intratracheal; D007610:Kallikreins / Q000037:antagonists & inhibitors; D010455:Peptides / Q000627:therapeutic use; D012307:Risk Factors
chemical_list: D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D050718:Complement C1 Inhibitor Protein; D010455:Peptides; C511194:ecallantide; C065679:icatibant; D007610:Kallikreins; D001920:Bradykinin
keywords: angioedema; angiotensin-converting enzyme inhibitor–induced angioedema; ecallantide; icatibant; kallikrein-kinin system