Acute Pancreatitis: A Rare Manifestation of Hereditary Angioedema Due to C1 Inhibitor Deficiency – Case Report

Abstract Hereditary angioedema (HAE) is a rare genetic disorder inherited in an autosomal dominant pattern. It is characterized by recurrent episodes of subcutaneous or submucosal edema affecting several organs. Gastrointestinal involvement typically presents as bowel edema, accompanied by severe abdominal pain, nausea, vomiting, and/or diarrhea, with biliary tract involvement being uncommon. Here, we report an unusual case of acute pancreatitis as the clinical manifestation of a type I HAE attack in a female patient from Brazil. This highlights the importance of considering HAE as a differential diagnosis for acute abdominal pain in emergency settings, thereby preventing unnecessary surgical procedures.