腹痛を契機に発見された遺伝性血管性浮腫の1例

Hereditary angioedema presenting with abdominal pain：a case report

遺伝性血管性浮腫（hereditary angioedema：HAE）は，C1インヒビター（C1-INH）の遺伝子異常に起因して全身の皮膚や粘膜に繰り返し血管性浮腫を生じる遺伝性疾患である。消化管粘膜に浮腫が生じると急性腹症の原因となるが，他の消化管疾患との鑑別が困難な場合がある。今回，腹痛を契機に発見されたHAEの1例を経験したので報告する。

Hereditary angioedema is a rare, inherited disease that causes recurrent angioedema of the skin and mucosa due to a mutation in the C1 inhibitor. We present a case of hereditary angioedema in a female in her 20s who presented with acute abdomen. A CT scan performed at the time of transportation showed wall thickening in the duodenum, but it had improved on the contrast-enhanced CT taken approximately 14 hours later, and had appeared newly in the stomach. Hereditary angioedema was suspected based on decreased serum C4 levels and a family history of recurrent facial edema. The C1 inhibitor activity was measured and found to be decreased, leading to a diagnosis of an attack of hereditary angioedema.