Angioedema: etiology, pathophysiology, current and emerging therapies.

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.

DISCUSSION

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.