Hereditary angioedema (HAE) is a rare genetic condition whose main symptoms are recurrent swelling in the skin, mucosa, and internal organs. Recent studies suggested that the regulation of the inflammatory response and the complement cascade are two of the pathways significantly enriched in the Canary Islands, Spain. Here, we describe the first HAE patient series in this region. Forty-one patients (33 F, 8 M) and nine healthy relatives belonging to twenty-nine families were recruited for this study, obtaining their clinical and demographic features using a data collection form, as well as blood samples for biochemical analysis. The mean age of patients was 36.8 years (ranging from 4 to 72 years). Positive family history of HAE was reported in 13 patients (32.5%), and a mean diagnosis delay of 7.9 (±12.5) years was estimated, ranging from months to 50 years. Cutaneous edema was the most common symptom (53.6%), while airway symptoms was present in 11 patients. Prophylactic treatment was indicated for 23 patients, while 14 also require on-demand rescue treatment. We estimate a minimum prevalence of 1.25:100,000 for HAE due to C1-INH deficiency or dysfunction in the Canary Islands, which is higher than the estimates for mainland Spanish populations. HAE continues to be a disease poorly recognized by health care professionals due to its confusing symptoms, leading to longer diagnosis delay. Altogether, the evidence reinforces the need for a rapid and accurate diagnosis and precision medicine-based studies to improve the patient’s quality of life.

Background/Objectives: The aim of this study was to evaluate the tolerability and effectiveness of subcutaneous immunotherapy (SCIT) in allergic adults and children treated with a polymerized-glutaraldehyde undiluted mixture of house dust mites (HDMs) under routine clinical practice. Methods: This was an observational, ambispective, controlled, real-world, multicenter study including patients ≥ 5 years with allergic rhinitis (AR), due to Dermatophagoides sensitization. Patients who started AIT with a D. pteronyssinus/D. farinae extract and those who continued symptomatic treatment were included in the treatment (DP&DF) and untreated (UT) groups, respectively. We evaluated adverse reactions (ARs) and changes in effectiveness variables through changes in symptoms, disease control, medication use, and patient- and investigator-reported outcomes. Results: We included 130 patients in the DP&DF group, and 90 (69.2%) adults, 23 adolescents (17.7%), 17 (13.1%) children, and 94 patients in the UT group. Patients received treatment for a mean (SD) of 9.01 (3.1) months at the time of evaluation. Seven (5.4%) patients, all adults, reported eight ARs, five local and three systemic (mean rate of 0.62 ARs per 100 injections); all recovered, and epinephrine was not required. The proportion of patients reporting no rhinitis symptoms at follow-up significantly increased (+13.6%; p < 0.001). Rhinitis frequency, intensity, and control significantly improved overall and in specific age groups. Similarly, the proportion of patients reporting no asthma symptoms at follow-up significantly increased (+29.0%; p < 0.001). The use of all symptomatic medications significantly decreased, while the UT group showed no significant changes, except for worsened asthma classification and control in specific age groups. Both investigators and patients perceived a marked improvement in symptoms and medication use, with high satisfaction scores reported on the visual analogue scale. Conclusions: A subcutaneous allergen extract with a mixture of HDMs is safe and effective for allergic rhinitis and asthma in adults and children in the real-world setting.