D2.50 - Hereditary angioedema; single center experience

Hereditary angioedema (HAE) is a rare disease with recurrent angioedema attacks resulting from excessive bradykinin accumulation in tissues. HAE is mainly divided into 2 main groups. The first is the C1 esterase inhibitor (C1-INH) deficiency-related type in which C1-INH antigen level (type 1) or function (type 2) is low. The other one is the type in which C1-INH level and function are normal, called normal C1-INH HAE. In our study, we aimed to present the demographic characteristics, clinical findings and prognosis of our patients with HAE followed up in our center.

Patients with HAE who were followed up in the Department of Pediatric Immunology and Allergy at Sakarya University Training and Research Hospital between 2013 and 2025 were evaluated retrospectively in terms of their characteristics at the time of diagnosis, demographic characteristics, attack characteristics, treatment and response to treatment.

19 of the patients with HAE were female and 10 were male. 76% of the patients had type 1 and 24% had type 2 HAE. There is no normal C1-INH HAE patient followed up in our clinic yet. Of our 29 patients, 20 were symptomatic and 9 were asymptomatic. Asymptomatic patients consisted of patients detected in family screening. The mean age of symptom onset in symptomatic patients was 12.6 years and the mean age at diagnosis delay was 9.3 years. The most common initial findings in our patients were abdominal pain (45%) and extremity (50%) attacks, while the first attack in 1 patient presented as angioedema of the eyes. Five of our patients had a history of laparotomy before diagnosis. Our patient who had the most frequent attacks described 8-9 attacks per month, while the mean number of monthly attacks in all our patients was 2.8. In 1 of our patients, erythema marginatum was prominently observed before the attack. The most common triggers of attacks were stress, fatigue, menstruation, trauma and interventional procedures. Icatibant and plasma C1-INH derivative were used in the treatment of attacks in our patients. There were no uncontrolled and severe attacks.  

Although our patient data was compatible with the clinical and laboratory features of HAE, which is usually seen in childhood and reported in the literature, some rare features unique to our center were also present.