Brazilian guidelines for the diagnosis and treatment of hereditary angioedema

Hereditary angioedema classification: Expanding knowledge by genotyping and endotyping

Hereditary angioedema (HAE) encompasses a group of diseases characterized by recurrent, genetically mediated angioedema associated with increased vascular permeability primarily due to bradykinin. The disease poses diagnostic challenges, leading to underdiagnosis and delayed therapy. Severe manifestations include laryngeal and intestinal angioedema, contributing to significant morbidity and mortality. If left undiagnosed, the estimated mortality rate of the disease ranges from 25% to 40% due to asphyxiation caused by laryngeal angioedema. There is a pressing need to enhance awareness of hereditary angioedema and its warning signs. The acronym "H4AE" may facilitate the memorization of these signs. This study comprehensively reviews clinical, laboratory, and physiopathological features of documented HAE subtypes. The study advocates for an improved HAE classification based on endotypes, building on the knowledge of angioedema pathophysiology. The proposed endotype classification of HAE offers a clear and applicable framework, encouraging advancements in disease understanding and classification.

Long-term Prophylaxis with Androgens in the management of Hereditary Angioedema (HAE) in emerging countries

Hereditary angioedema (HAE) is a rare autosomal dominant genetic disease characterized by repetitive subcutaneous or submucosal angioedema, activation of the kinin system, and increased vascular permeability. C1-inhibitor (C1-INH) deficiency, the main mechanism of HAE pathogenesis, occurs when abnormal activation of plasma kallikrein, bradykinin, and factor XII, or mutation of genes such as SERPING1 cause quantitative or functional C1-INH defects. Although androgens are not approved for HAE treatment in many countries, they are widely used in China and Brazil to reduce the frequency and severity of HAE attacks. The long-term adverse effects of androgen treatment are concerning for both physicians and patients. Virilization, weight gain, acne, hirsutism, liver damage, headache, myalgia, hematuria, menstrual disorders, diminished libido, arterial hypertension, dyslipidemia, and anxiety/depression are commonly observed during long-term treatment with androgens. These adverse effects can affect the quality of life of HAE patients and often lead to treatment interruption, especially in women and children. In-depth studies of the pathogenesis of HAE have led to the approval of alternative treatment strategies, including plasma-derived C1 inhibitor, recombinant human C1 inhibitor, plasma Kallikrein inhibitor (ecallantide; lanadelumab), and bradykinin B2 receptor antagonist (icatibant), some of which have achieved satisfactory results with mostly non-serious side effects. Therefore, a new standard of medical care may expand possibilities for the management of HAE in emerging countries.

Consider Hereditary Angioedema in the Differential Diagnosis for Unexplained Recurring Abdominal Pain

Health care providers are likely to encounter patients with recurrent unexplained abdominal pain. Because hereditary angioedema (HAE) is a rare disease, it may not be part of the differential diagnosis, especially for patients who do not have concurrent skin swelling in addition to abdominal symptoms. Abdominal pain is very common in patients with HAE, occurring in up to 93% of patients, with recurrent abdominal pain reported in up to 80% of patients. In 49% of HAE attacks with abdominal symptoms, isolated abdominal pain was the only symptom. Other abdominal symptoms that commonly present in patients with HAE include distension, cramping, nausea, vomiting, and diarrhea. The average time from onset of symptoms to diagnosis is 6 to 23 years. Under-recognition of HAE in patients presenting with predominant gastrointestinal symptoms is a key factor contributing to the delay in diagnosis, increasing the likelihood of unnecessary or exploratory surgeries or procedures and the potential risk of related complications. HAE should be considered in the differential diagnosis for patients with unexplained abdominal pain, nausea, vomiting, and/or diarrhea who have complete resolution of symptoms between episodes. As highly effective targeted therapies for HAE exist, recognition and diagnosis of HAE in patients presenting with isolated abdominal pain may significantly improve morbidity and mortality for these individuals.

Prospective Study on the Efficacy and Impact of Cascade Screening and Evaluation of Hereditary Angioedema (CaSE-HAE)

BACKGROUND

Recommendations regarding family screening for hereditary angioedema (HAE) remain variable and mostly based on expert opinion. Studies evaluating its implementation and efficacy are lacking.

OBJECTIVES

A novel HAE screening program was established to evaluate the efficacy and impact of cascade family screening (CFS) for at-risk relatives.

METHODS

Potential HAE relatives were screened through the CFS approach. Prospective data on clinical, psychological, and HAE-related outcomes were collected at baseline and 1-year follow-up. Longitudinal outcomes were analyzed and compared between index patients and those given a diagnosis through CFS.

RESULTS

Of 179 relatives, 53% were contactable, 67% of whom consented to screening. Twenty-nine patients (46%) were newly given the diagnosis of HAE; half were symptomatic at baseline (52%). There was a stronger trend toward higher diagnostic yield among first-degree families, although this did not meet statistical significance (57.6% vs 33.3%; P = .077). Among symptomatic patients, there was a higher proportion with complete annual HAE remission (15% vs 46%; P = .021) and a reduction in annual HAE-related hospital admissions (1 vs 0; P = .016) and length of stay (3 vs 2 days; P = .001) after 1 year. Among all patients, there were reduced Hospital Anxiety and Depression Scale-anxiety (14.35 ± 6.32 vs 6.47 ± 4.14; P = .001) and improved Angioedema Quality of Life scores (55% vs 35%; P < .001). By extrapolation, CFS led to a reduction of at least HK $1,200 (US $153) in HAE-related costs per patient per year. Screening using a greater than suggested C4 cutoff of 22.9 mg/dL yielded superior sensitivity (100%) and specificity (77%).

CONCLUSION

Cascade family screening is an effective approach to family screening in HAE, improving clinical and psychological outcomes, and reducing disease-related costs.

The Icatibant Outcome Survey: 10 years of experience with icatibant for patients with hereditary angioedema

In patients with hereditary angioedema (HAE), bradykinin causes swelling episodes by activating bradykinin B₂ receptors. Icatibant, a selective bradykinin B₂ receptor antagonist, is approved for on-demand treatment of HAE attacks. The Icatibant Outcome Survey (IOS; NCT01034969) is an ongoing observational registry initiated in 2009 to monitor effectiveness/safety of icatibant in routine clinical practice. As of March 2019, 549 patients with HAE type 1 or 2 from the IOS registry had been treated, for 5995 total attacks. This article reviews data published from IOS over time which have demonstrated that effectiveness of icatibant in a real-world setting is comparable to efficacy in clinical trials; one dose is effective for the majority of attacks; early treatment (facilitated by self-administration) leads to faster resolution and shorter attack duration; effectiveness/safety of icatibant has been shown across a broad range of patient subgroups, including children/adolescents and patients with HAE with normal C1 inhibitor levels; and tolerability has been demonstrated in patients aged ≥65 years. Additionally, this review highlights how IOS data have provided valuable insights into patients' diagnostic journeys and treatment behaviors across individual countries. Such findings have helped to inform clinical strategies and guidelines to optimize HAE management and limit disease burden. This research was sponsored by Takeda Development Center Americas, Inc. Takeda Development Center Americas, Inc., provided funding to Excel Medical Affairs for support in writing and editing this manuscript.

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.

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.

Clinical features of hereditary angioedema and warning signs (H4AE) for its identification

OBJECTIVES

The study describes a case series of hereditary angioedema with C1 Inhibitor Deficiency (C1INH-HAE) in order to corroborate six clinical warning signs "HAAAAE (H4AE)" to enable early identification of this disease.

METHODS

The authors analyzed the C1INH-HAE cohort to analyze the clinical aspects of the present study's patients and corroborate the six clinical warning signs of the Hereditary Angioedema Brazilian Guidelines. Data regarding demographics, the onset of disease, time to diagnosis, frequency of attacks per year, organs involved, triggers, crisis duration and their outcomes, and disease treatment were collected. Then the authors developed an acronym, H4AE, to help healthcare professionals remember the warning signs.

RESULTS

The authors included 98 patients in the study, with a mean age of 38.1 years, 67.3% being female, and 75.3% with a family history of HAE. HAE diagnosis was delayed, on average, 13.7 years after its initial manifestation. Exploratory laparotomy was reported by 26.9%, and orotracheal intubation by 21.3% of the present study's patients; 61.3% and 30.3% of them were admitted at least once in the hospital and in the intensive care unit, respectively. The authors constructed an acronym "H4AE" with the six warning signs of HAE: Hereditary, recurrent Angioedema, Abdominal pain, Absence of urticaria, Absence of response to antihistamines, Estrogen association.

CONCLUSION

C1INH-HAE is still underdiagnosed and associated with high morbidity. The study showed clinical features of this disease, corroborating the warning signs, which may be useful in raising awareness and improving the diagnosis of C1INH-HAE. The authors suggest the acronym "H4AE" to remind the warning signs.

The Complex Interaction Between Polycystic Ovary Syndrome and Hereditary Angioedema: Case Reports and Review of the Literature

Importance

Hereditary angioedema (HAE) is a rare but severe disease, with high risk of death, and attacks have been associated to high estrogen levels. Polycystic ovary syndrome (PCOS) is a common hyperandrogenic condition, which is frequently treated with combined oral contraceptives.

Objective

The aim of this study was to describe 2 clinical cases of young women diagnosed as having PCOS who developed HAE attacks after the introduction of combined estrogen-progestin pills to treat PCOS symptoms.

Evidence Acquisition

Literature review of sex hormones' role in genesis of HAE attacks and possible mechanisms involved.

Results

In the cases reported, after initiation of combined contraceptives, patients presented with facial swelling with airway involvement (laryngeal edema) and abdominal pain. They had a familial history of angioedema and normal C1 inhibitor (C1-INH) levels, leading to the diagnosis of HAE with normal C1-INH (HAEnC1-INH) or HAE type III. After suspension of exogenous estrogen, patients remained asymptomatic from HAE.

Conclusions and Relevance

HAEnC1-INH is an estrogen-dependent form of HAE. It is well established that exogenous estrogen triggers attacks of all types of HAE. However, this is the first description of the association between PCOS and HAE, in which PCOS could be masking HAE symptoms. We propose that PCOS might have a protective role regarding HAE attacks, because of its particular hormonal features, that is, hyperandrogenism and relative stable levels of estradiol. The use of combined estrogen-progestin compounds in women with PCOS and HAE must be avoided, and treatment must be individualized.

Brazilian Guidelines for Hereditary Angioedema Management - 2017 Update Part 1: Definition, Classification and Diagnosis

Hereditary angioedema is an autosomal dominant disease characterized by recurrent angioedema attacks with the involvement of multiple organs. The disease is unknown to many health professionals and is therefore underdiagnosed. Patients who are not adequately diagnosed and treated have an estimated mortality rate ranging from 25% to 40% due to asphyxiation by laryngeal angioedema. Intestinal angioedema is another important and incapacitating presentation that may be the main or only manifestation during an attack. In this article, a group of experts from the "Associação Brasileira de Alergia e Imunologia (ASBAI)" and the "Grupo de Estudos Brasileiro em Angioedema Hereditário (GEBRAEH)" has updated the Brazilian guidelines for the diagnosis and treatment of hereditary angioedema.

Therapeutic complement inhibition: a promising approach for treatment of neuroimmunological diseases

INTRODUCTION

Autoimmunity is an important cause of disease both in the central and peripheral nervous systems. Aetiologies and clinical manifestations are complex and heterogeneous. Inappropriate control of complement activation at inappropriate sites has been recognized as a major determinant in several neurological conditions, including Guillain-Barré syndrome and neuromyelitis optica. In each case pathogenesis is thought to be associated with generation of autoantibodies which upon binding guide activation of the complement system to self-tissue. Areas covered: Modulation of the complement system activation at such sites may represent a novel therapeutic approach for treatment of immune-mediated inflammatory conditions. In this review we focus on the therapeutic effects of complement inhibitors in Guillain-Barré syndrome and neuromyelitis optica and highlight recent developments within the field. Expert Commentary: Conventional first line treatment strategies in GBS and NMO have the potential disadvantage of causing widespread immunosuppressive effects. A more targeted approach may therefore be more effective and less disruptive to the immune system, especially in the case of NMO, which requires long term immunosuppression. Modulation of the complement system may hold the key and has already been shown to be of clinical benefit in other non-neurological conditions, including paroxysmal nocturnal hemoglobinuria and hereditary angioedema.

Icatibant, an inhibitor of bradykinin receptor 2, for hereditary angioedema attacks: prospective experimental single-cohort study

CONTEXT AND OBJECTIVE

Hereditary angioedema (HAE) with C1 inhibitor deficiency manifests as recurrent episodes of edema involving the skin, upper respiratory tract and gastrointestinal tract. It can be lethal due to asphyxia. The aim here was to evaluate the response to therapy for these attacks using icatibant, an inhibitor of the bradykinin receptor, which was recently introduced into Brazil.

DESIGN AND SETTING

Prospective experimental single-cohort study on the efficacy and safety of icatibant for HAE patients.

METHODS

Patients with a confirmed HAE diagnosis were enrolled according to symptoms and regardless of the time since onset of the attack. Icatibant was administered in accordance with the protocol that has been approved in Brazil. Symptom severity was assessed continuously and adverse events were monitored.

RESULTS

24 attacks in 20 HAE patients were treated (female/male 19:1; 19-55 years; median 29 years of age). The symptoms were: subcutaneous edema (22/24); abdominal pain (15/24) and upper airway obstruction (10/24). The time taken until onset of relief was: 5-10 minutes (5/24; 20.8%); 10-20 (5/24; 20.8%); 20-30 (8/24; 33.4%); 30-60 (5/24; 20.8%); and 2 hours (1/24; 4.3%). The time taken for complete resolution of symptoms ranged from 4.3 to 33.4 hours. Adverse effects were only reported at injection sites. Mild to moderate erythema and/or feelings of burning were reported by 15/24 patients, itching by 3 and no adverse effects in 6.

CONCLUSION

HAE type I patients who received icatibant responded promptly; most achieved improved symptom severity within 30 minutes. Local adverse events occurred in 75% of the patients.