Recurrent and acute abdominal pain as the main clinical manifestation in patients with hereditary angioedema.

Hereditary angioedema (HAE) is a rare disease that often leads to misdiagnosis. The delay of diagnosis is > 10 years in China. Recurrent and acute abdominal pain is one of the common symptoms of HAE. Because of the high misdiagnosis rate, it usually results in unnecessary surgical procedures. This study focused on the clinical symptoms and management of HAE-related abdominal attacks in Chinese patients to provide some new insight for the emergency department (ED) physicians and gastroenterologists. A Web-based survey was conducted among 107 patients with HAE from 94 unrelated families. Detailed questions with respect to the abdominal attacks were asked, including the frequency, symptoms, and duration before and after confirmed diagnosis. The demographic characteristics, diagnosis process, and treatment outcomes were also included. Approximately 70% of the patients with HAE presented with abdominal symptoms during the onset of edema, mostly characterized by pain (94.8%), nausea (83.1%), vomiting (83.1%), diarrhea (59.7%), and constipation (23.4%). The patients were easily misdiagnosed as having gastroenteritis (35.1%) and appendicitis (10.4%), and 24.7% of them received unnecessary appendectomy or laparotomy. Danazol, a widely used drug for long-term prophylaxis of HAE in China, can reduce the attack frequency and alleviate the abdominal symptoms, but the adverse effects are also significant and more severe in women. Abdominal symptoms are common and important clinical features of HAE but are easily confused with other gastrointestinal diseases. ED physicians and gastroenterologists should consider HAE when patients experience recurrent and unexplained abdominal pain. Proper medical treatment should be administered in a timely manner if an HAE diagnosis is confirmed and efforts are required to increase access in China to medications both for on-demand treatment and long-term prophylaxis.