Clinical features of hereditary angioedema involving the gastrointestinal tract: A retrospective analysis.

Background: Hereditary angioedema (HAE) is a rare, severe, disabling, and life-threatening disorder characterized by recurrent and unpredictable edema of skin and mucous membranes. Gastrointestinal edema, often presenting as abdominal pain, is common but frequently misdiagnosed, leading to unnecessary surgeries. This study aims to characterize gastrointestinal edema in HAE patients to improve early diagnosis and guide treatment. Method: We analyzed 61 patients with HAE who were admitted in our hospital between April 1, 2023 and August 31, 2025. Data on demographic characteristics, clinical manifestations, laboratory findings, imaging results, and treatment outcomes were collected through questionnaires and hospital electronic records. Result: Among the patients, 86.9% experienced gastrointestinal edema, mostly characterized by abdominal pain (94.3%), nausea (79.2%), and diarrhea (71.7%). Misdiagnosis occurred in 73.6% of cases, and 22.6% underwent unnecessary surgeries. The median age of gastrointestinal edema onset was 16.0 years, with the most severe episodes occurring at a median age of 25.0 years. The median annual frequency of attacks was 4.0/year, with a median severity score of 7.0. Acute attacks showed elevated D-dimer, white blood cells, neutrophils, and hemoglobin. CT imaging frequently revealed intestinal wall thickening and abdominal-pelvic effusion. Lanadelumab demonstrated superior efficacy over danazol in reducing both the frequency and severity of edema attacks, while icatibant significantly shortened the duration of edema episodes. Conclusion: This study updates the clinical and imaging features of gastrointestinal edema in Chinese patients with HAE, identifies biomarkers of gastrointestinal edema attacks, and highlights the efficacy of lanadelumab and icatibant, aiding timely diagnosis and treatment.