Urticaria y angioedema

Abstract

Hives (urticaria) is a skin condition whose elemental lesion is the wheal (a raised, evanescent and itchy lesion affecting superficial dermis layers of the dermis). Vasodilation and mononuclear infiltrate are the typical histological feature of hives. In urticarial vasculitis blood vessels are involved. Acute urticaria is the commonest type of hives, affecting 20% of the population at some point in their life. The treatment of choice is to avoid the trigger factor, if known, and second-generation antihistamines. In the most aggressive forms, immunomodulators such as tacrolimus can also be used. Angioedema is defined as a localized, subcutaneous, self-limited swelling resulting of increased fluid in the interstitial space; usually prefers skin areas with loose connective tissue: face, lips, mouth, and upper airways; nevertheless, it can also affect the genitals and intestinal wall, appearing, in this case, with abdominal pain. Angioedema can appear either isolation or associated with other conditions such as urticaria or anaphylaxis. Hereditary or acquired angioedema, caused by inhibitory C1 deficiency, has be suspected in isolated and recurrent angioedema cases.