Hereditary angioedema with C1 inhibitor deficiency: delay in diagnosis in Europe

Background: Hereditary angioedema (HAE) is a rare, debilitating, and potentially life-threatening disease characterized by recurrent edema attacks. Important advances in HAE treatment have been made, including the development of new therapies for treating or preventing attacks. Nevertheless, the disease is still frequently misdiagnosed and inappropriately treated, potentially exposing patients with laryngeal attacks to the risk of asphyxiation. Methods: The Icatibant Outcome Survey (IOS) is an international, observational study that documents the clinical outcome of HAE patients eligible for treatment with icatibant. Patient ages at first symptoms and at diagnosis were recorded at enrolment, and the delay between first symptoms and diagnosis was calculated. Results: The median [range] diagnostic delay in HAE type I and II patients across eight countries was 8.5 years [0-62.0]. The median delay in diagnosis was longer for HAE type II versus type I (21 versus 8 years, respectively), although this did not quite reach statistical significance. Conclusions: Although it can be difficult to differentiate HAE symptoms from those of more common angioedema sub-types (e. g. idiopathic or acquired angioedema), our results show that HAE type I and II patients have an unacceptable delay in diagnosis, even those with a family history of the disease. Raising physician awareness of this disabling and potentially fatal disease may lead to a more accurate diagnosis and timely treatment.