D2.349 - Hereditary Angioedema in Bulgaria: an update on patient characteristics and treatment modalities

Hereditary angioedema (HAE) is a rare condition, leading to recurrent swelling episodes. Most cases are associated with C1-inhibitor (C1INH) deficiency or dysfunction, though some patients have normal C1INH, and suspected pathogenic variants in other genes responsible for the kallikrein-kinin system or intrinsic vascular endothelial dysfunction. Globally, HAE affects approximately 1 in 50,000 individuals, with significant challenges in timely diagnosis and treatment. In Bulgaria, limited disease awareness and access to specialized care hinder optimal management.

Data was extracted from patient records of a tertiary university clinic, a dedicated ACARE centre, and was analyzed for demographics, disease characteristics, and therapeutic approaches.

The cohort consists of 120 patients: 69 females (57.5%) and 51 males (42.5%). Median age was 43.5 years (1-87 years). 92 patients had HAE-C1INH Type 1, 16 patients HAE-C1INH Type 2, 10 patients had HAE-nlC1INH and 2 had AAE-C1INH. 19 of the patients were pediatric.

Disease onset for patients with HAE-C1INH was 12 (1-75), and 37 (7-64) for HAE-nlC1INH. Family history was documented for 90% of patients (n=99). 

The delay of diagnosis was 12 (0-62) years.

Therapeutic modalities included 32% of patients receiving prophylactic therapy for HAE (lanadelumab, berotralstat, scpdC1INH, or clinical trials), while other patients treating acute HAE manifestation with rescue therapy (rhC1INH, pdC1INH, icatibant, or clinical trials). 2 patients have died from fatal laryngeal angioedema in the last 5 years.

This analysis underscores the significant burden of HAE in Bulgaria and highlights the need for systemic improvements in disease awareness, diagnosis and treatment. Enhanced awareness among pediatric patients, and equitable access to advanced therapies are vital for aligning Bulgaria’s HAE management with global standards and improving outcomes for patients.