Hereditary angioedema. Complex symptoms can make diagnosis difficult

Although rare, hereditary angioedema is a potentially life-threatening disorder that can be difficult to diagnose. It is characterized by a deficiency in C1 esterase inhibitor (C1 INH). Manifestations include gastrointestinal, subcutaneous, and respiratory edema. Factors that trigger episodes vary. Symptoms typically last 48 to 72 hours, but they can last 4 hours to 1 week. Treatment includes prophylactic therapy with attenuated androgens or antifibrinolytic agents. Acute episodes can be medical emergencies, and airway management is a major concern. The treatment of choice in an acute episode is administration of plasma concentrate of C1 INH.