Definition, acronyms, nomenclature, and classification of angioedema (DANCE): AAAAI, ACAAI, ACARE, and APAAACI DANCE consensus.

BACKGROUND: Angioedema (AE) manifests with intermittent, localized, self-limiting swelling of the subcutaneous and/or submucosal tissue. AE is heterogeneous, can be hereditary or acquired, may occur only once or be recurrent, may exhibit wheals or not, and may be due to mast cell mediators, bradykinin, or other mechanisms. Several different taxonomic systems are currently used, making it difficult to compare the results of studies, develop multicenter collaboration, and harmonize AE treatment. OBJECTIVE: We developed a consensus on the definition, acronyms, nomenclature, and classification of AE (DANCE). METHODS: The initiative involved 91 experts from 35 countries and was endorsed by 53 scientific and medical societies, and patient organizations. A consensus was reached by online discussion and voting using the Delphi process over a period of 16 months (June 2021 to November 2022). RESULTS: The DANCE initiative resulted in an international consensus on the definition, classification, and terminology of AE. The new consensus classification features 5 types and endotypes of AE and a harmonized vocabulary of abbreviations/acronyms. CONCLUSION: The DANCE classification complements current clinical guidelines and expert consensus recommendations on the diagnostic assessment and treatment of AE. DANCE does not replace current clinical guidelines, and expert consensus algorithms and should not be misconstrued in a way that affects reimbursement of medicines prescribed by physicians using sound clinical judgment. We anticipate that this new AE taxonomy and nomenclature will harmonize and facilitate AE research and clinical studies, thereby improving patient care.

The international WAO/EAACI guideline for the management of hereditary angioedema-The 2021 revision and update.

Hereditary angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1 inhibitor (type 1) and HAE with dysfunctional C1 inhibitor (type 2), by providing guidance on common and important clinical issues, such as: (1) How should HAE be diagnosed? (2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? (3) What are the goals of treatment? (4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast-feeding women? and (5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients.

A Core Outcome Set for Efficacy of Acute Treatment of Hereditary Angioedema.

BACKGROUND: Clinical trials investigating drugs for the acute treatment of hereditary angioedema attacks have assessed many different outcomes. This heterogeneity limits the comparability of trial results and may lead to selective outcome reporting bias and a high burden on trial participants. OBJECTIVE: To achieve consensus on a core outcome set composed of key outcomes that ideally should be used in all clinical efficacy trials involving the acute treatment of hereditary angioedema attacks. METHODS: We conducted a Delphi consensus study involving all relevant parties: patients with hereditary angioedema, hereditary angioedema expert clinicians and clinical researchers, pharmaceutical companies, and regulatory bodies. Two Internet-based survey rounds were conducted. In round 1, panelists indicated the importance of individual outcomes used in clinical trials on a 9-point Likert scale. Based on these results, a core outcome set was developed and voted on by panelists in round 2. RESULTS: A total of 58 worldwide panelists completed both rounds. The first round demonstrated high importance scores and substantial agreement among the panelists. In the second round, a consensus of 90% or greater was achieved on a core outcome set consisting of five key outcomes: change in overall symptom severity at one predetermined time point between 15 minutes and 4 hours after treatment, time to end of progression of all symptoms, the need for rescue medication during the entire attack, impairment of daily activities, and treatment satisfaction. CONCLUSIONS: This international study obtained a high level of consensus on a core outcome set for the acute treatment of hereditary angioedema attacks, consisting of five key outcomes.

The international WAO/EAACI guideline for the management of hereditary angioedema - The 2021 revision and update.

Hereditary Angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2), by providing guidance on common and important clinical issues, such as: 1) How should HAE be diagnosed? 2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? 3) What are the goals of treatment? 4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast feeding women? 5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients.

Resolution of Laryngeal Oedema in a Patient with Acquired C1-Inhibitor Deficiency. a Case Report.

INTRODUCTION: Laryngeal oedema caused by acquired angioedema due to C1-inhibitor deficiency (C1-INH-AAE) is a life-threatening condition. The swelling is bradykinin mediated and will not respond to the usual treatment with antihistamines, corticosteroids, or epinephrine. Instead, kallikrein-bradykinin-targeted therapies should be used promptly to prevent asphyxiation. CASE PRESENTATION: A 43 years old female presented at the Hereditary Angioedema Centre reporting a one-year history of peripheral, facial, and neck oedema. Treatment with antihistamines and corticosteroids had been ineffective. Laboratory results showed complement level deficiencies and monoclonal gammopathy characterised as immunoglobulin M. An abdominal ultrasound revealed splenomegaly. A bone marrow biopsy was normal. Based on these data, the diagnosis of C1-INH-AAE associated with monoclonal gammopathy of uncertain significance (MGUS) was made. As C1-INH-AAE can present with life-threatening, standard treatment-resistant laryngeal oedema, an emergency care treatment plan was proposed, and the patient was advised to present to the emergency department (ED) with this medical letter. Based on these recommendations, three laryngeal attacks were successfully treated in the ED with recombinant human C1-inhibitor (two attacks) and fresh frozen plasma (one attack). After these episodes, the patient was prescribed prophylactic treatment with antifibrinolytics. No further angioedema attacks were reported by the patient at the 18 months follow-up visit. CONCLUSIONS: Because angioedema of the upper airways is a life-threatening condition, recognising the specific type of swelling by the emergency physician is critical in providing immediate and effective treatment to reduce the associated risk of asphyxiation. C1-INH-AAE being a rare disorder, patients should have available an emergency care treatment plan with recommendations of acute treatment possibilities.