**Urticaria and Angioedema**

Burhan Engin, Muazzez Çiğdem Oba and Server Serdaroğlu

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/67772

#### **Abstract**

Urticaria is a common mast cell–mediated dermatosis presenting with pruritic erythematous superficial plaques also known as hives or wheals. Angioedema is an acute condition manifesting as localized edema affecting the skin and mucous membranes. In contrast with urticaria, itching is often absent, the skin appears normal and the edema occurs in deeper dermal and subcutaneous tissues in angioedema. Spontaneous urticaria can either be acute lasting less than 6 weeks or chronic with a duration of more than 6 weeks. In acute urticaria cases, an underlying cause, mostly medications, foods and infections, may be found in approximately 50% of patients. However, spontaneous urticaria is generally idiopathic. First-line treatment option for both acute and chronic urticaria is non-sedating H<sup>1</sup> antihistamines. Patients with recalcitrant disease are candidates for therapy with corticosteroids, immunosuppressives or omalizumab treatment. There are two different mechanisms causing angioedema. The first is mast cell mediated and is considered to be part of the spectrum of spontaneous or inducible urticarias. Patients present with angioedema alone or angioedema combined with urticaria. The second is bradykinin-induced angioedema, as observed in the hereditary angioedema and angiotensin-converting enzyme (ACE) inhibitor–induced angioedema.

**Keywords:** angioedema, spontaneous urticaria

#### **1. Introduction**

Urticaria is a common mast cell–mediated dermatosis presenting with pruritic erythematous superficial plaques also known as hives or wheals. There may be associated swelling in deep dermis or subcutaneous tissue leading to angioedema [1]. Angioedema is rather painful than pruritic and takes longer time to resolve in contrast to the wheals which usually disappear within 24 hours [2, 3]. The disease has considerable impact on patients' quality of life

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with dissatisfaction in private life and work being frequent [4]. Non-sedating H<sup>1</sup> antihistamines are the first line therapy for both acute and chronic urticaria. Apart from angioedema which is part of the spectrum of urticaria, there is bradykinin-induced angioedema, such as that observed in the hereditary angioedema characterized by angioedema without wheals. Management of isolated angioedema differs from that of urticaria involving both preventive measures and treatment of acute attacks [5].
