[Hereditary angioedema. A report of a case and literature review]

Hereditary angioedema is a congenital disorder with recurrent attacks of localized swelling of submucosal and subcutaneous tissue, or both caused by a deficiency of the plasma protein C1 inhibitor. It is caused by heterozygous defects in the C1 inhibitor gene located on chromosome 11q, and it has an autosomal dominant inheritance pattern. This disease afflicts 1 in 10,000 to 1 in 150,000 persons. Hereditary angioedema has been reported in all races, and no sex predominance has been found. Skin and visceral organs may be involved by the typically massive local edema. The most commonly involved viscera are the respiratory and gastrointestinal systems, and it can affect the upper airways resulting in severe life-threatening symptoms, including the risk of asphyxiation. There are three types of hereditary angioedema, which difference lies in the inheritance pattern and in the C1 esterase inhibitor and C4 concentrations. The treatment is complicated and it should be treated with intravenous purified C1 inhibitor concentrate; corticosteroids, antihistamines and epinephrine can be useful adjuncts but they are not effective. We report a patient with hereditary angioedema type 1 and make a review of the medical literature.