D2.268 - Clinical characteristics and Therapeutic Management of Hereditary Angioedema due to C1-Inhibitor Deficiency: A Retrospective Cohort Study in Colombia

Hereditary angioedema due to C1-inhibitor deficiency (HAE-C1INH) is a rare autosomal dominant disorder characterized by recurrent, non-histaminergic bradykinin-mediated angioedema.Despite its low prevalence, HAE is associated with substantial morbidity, impaired quality of life, emergency healthcare utilization, and risk of fatal laryngeal attacks.  However, real-world data  in Latin America remain limited. This study aimed to characterize the epidemiology, clinical burden, and attack frequency in patients with HAE-C1INH followed in a reference center in Colombia. 

We conducted a retrospective, observational cohort study based on medical record review of patients with confirmed HAE type I or II evaluated at a specialized allergy and immunology center in Cúcuta, Colombia, between 2014 and 2024. Demographic variables, age at symptom onset, age at diagnosis, diagnostic delay, family history, laboratory parameters (C4, C1-INH functional and quantitative levels), clinical manifestations, healthcare utilization, and number of attacks during the last year of follow-up were extracted. Patients were stratified according to lanadelumab exposure. Descriptive statistics were calculated using medians and interquartile ranges (IQR) or means with 95% confidence intervals (CI), as appropriate.

A total of 53 patients were included; 54.7% were female. Median age was 29 years, with median symptom onset at 12 years and median diagnostic age of 24 years, corresponding to a median diagnostic delay of 11 years. Family history was reported in 86.8% of cases.

Regarding clinical phenotype, abdominal edema was the most frequent manifestation (88.7%), followed by peripheral edema (75.5%). Laryngeal involvement occurred in 39.6% of patients. During the last year of follow-up, the overall median number of attacks was 5 (IQR 1–13), and 11.3% experienced >25 attacks/year. Lifetime HAE-related hospitalizations were documented in 14/53 patients (26.4%; 95%CI 16.0–39.6), ICU admission in 2/53 (3.8%; 95%CI 1.1–12.8), and intubation in 1/53 (1.9%; 95%CI 0.3–9.9). Lanadelumab long-term prophylaxis was used in 17/53 patients (32.1%) 

This real-world cohort of patients with hereditary angioedema in Colombia reveals a significant diagnostic delay despite early symptom onset and high rates of positive family history. The predominance of abdominal and peripheral edema, together with frequent laryngeal involvement, confirms ongoing risk of severe and life-threatening episodes.

Although the median attack rate was moderate, a subset exhibited high disease burden, including recurrent attacks and hospital-based care. More than one quarter required hospitalization, and airway compromise necessitating ICU admission or intubation was documented, underscoring disease severity.

Despite widespread use of on-demand therapy, only one-third received lanadelumab prophylaxis, indicating potential gaps in access or treatment optimization. These findings support earlier diagnosis, structured long-term management, and improved implementation of prophylaxis to reduce morbidity and healthcare utilization.