Rationale: Hereditary angioedema (HAE) is a rare genetic disorder caused by C1 esterase inhibitor (C1-INH) deficiency or dysfunction. Presentation with isolated abdominal pain is uncommon, often leading to diagnostic delays and inadequate pain management. Effective pain control is essential to improve patient comfort and prevent complications. Patient concerns: A 21-year-old male with type II HAE presented exclusively with recurrent severe abdominal pain and experienced a transient loss of consciousness attributed to a pain-induced vagal reflex. Diagnoses: Diagnosis of type II HAE was confirmed based on clinical presentation, laboratory findings of C1-INH dysfunction, and exclusion of other causes of abdominal pain. Interventions: The patient received multidisciplinary care including symptom-based nursing, targeted pharmacological therapy with lanadelumab, psychological support, and nutritional management. Outcomes: Following lanadelumab administration, the patient’s abdominal pain improved significantly within 2 hours and completely resolved within 8 hours. Symptom relief was sustained at 3-month follow-up with no recurrence. Lessons: This case underscores the importance of early recognition of HAE presenting solely with abdominal pain and demonstrates that multidisciplinary, targeted pain management can lead to rapid and sustained symptom relief. Awareness of such atypical presentations is critical for optimizing outcomes in HAE patients.
Li et al. (Fri,) studied this question.