Acute pancreatitis due to hereditary angioedema

Background: Hereditary angioedema (HAE) is an infrequent disorder characterized by abnormalities in the levels and/or function of complement C1 esterase inhibitor. Clinical manifestations of HAE are due to recurrent episodic swelling of the subcutaneous or submucosal tissue. When swelling involves the gastrointestinal mucosa, patients may present with nausea, vomiting, diarrhea, and severe abdominal pain. However, HAE is almost never suspected as a potential cause of acute pancreatitis. Objective: To describe a patient with HAE-associated pancreatitis requiring intensive medical care that responded favorably to conservative and supportive measures. Methods: Various tests were performed, including abdominal imaging, measurement of pancreatic enzymes levels, liver function tests, measurement of complement levels, and endoscopic retrograde cholangiopancreatography. Results: The results of these tests confirmed the diagnosis of HAE-associated acute pancreatitis. No other obvious origin, such as gallstones or alcohol use, was identified. Conclusion: This case illustrates the need for a high clinical suspicion of acute pancreatitis when caring for patients with HAE who present with abdominal symptoms. There continues to be an urgent need for better and additional therapeutic options for HAE patients, including those to prevent and abort ongoing attacks.