Hereditary angioedema with C1-inhibitor deficiency retrospective study of a population of 194 patients

ABSTRACT BACKGROUND: Hereditary angioedema due to C1-inhibitor deficiency is a rare disease caused by deficiency and/or low functional activity of C1-inhibitor. The main symptom of hereditary angioedema is recurrent angioedema in various localizations which can lead to temporary incapacity or even death. AIMS: To describe a population of patients with hereditary angioedema with C1-inhibitor deficiency from NRC Institute of Immunology FMBA of Russia registry. Another aim of our study was to identify predictors of upper respiratory tract angioedema. METHODS: 194 patients from NRC Institute of Immunology FMBA of Russia registry from 124 unrelated families with a diagnosis of hereditary angioedema with C1-inhibitor deficiency, confirmed in accordance with accepted diagnostic standards, were enrolled in the retrospective descriptive study. RESULTS: Overall, 194 patients were included in the analysis (70% female and 30% male). The mean age of patients was 3517 years. 89% of patients had hereditary angioedema type I, 11% of patients had hereditary angioedema type II. The mean age of clinical onset was 119 years. 98% of participants had a history of at least one episode of peripheral angioedema, 86% experienced abdominal attacks, 86% - facial swellings, 49% - laryngeal attacks. The mean diagnostic delay was 17,511,24 years. The older the patient is, the more possible laryngeal attacks (P0.001), facial and neck swellings (P0.001), and abdominal attacks are (P=0.031). There were no significant differences in clinical features between men and women. CONCLUSIONS: There is a problem of a long diagnostic delay of hereditary angioedema in Russia. We have identified a number of warning criteria of hereditary angioedema as a consequence of the study: the presence of a family history, a combination of recurrent angioedema and abdominal attacks, the onset of angioedema and/or abdominal attacks in early childhood. The existence of such criteria will make it possible to optimize the diagnosis of hereditary angioedema. Moreover, we have identified risk factors of the development of life-threatening angioedema: the patient's age (the older the patient, the higher the risk), as well as a history of angioedema of the face and neck.