Hereditary angioedema as a cause of transient abdominal pain

Isolated angioedema, without urticaria or itching, occurs as a result of an inherited or acquired defect in C1 esterase inhibitor activity. Most cases of isolated angioedema are caused by one of two types of hereditary angioedema (HAE). We present a case of the much rarer type II HAE with abdominal pain as the sole presenting symptom. Hereditary angioedema should be suspected in young adults with episodic abdominal pain for which common causes have been excluded. A history of HAE or episodic abdominal pain in family members is not necessary for diagnosis.