2010 International consensus algorithm for the diagnosis, therapy and management of hereditary angioedema

Interplay between on-demand treatment trials for hereditary angioedema and treatment guidelines

Over the past 2 decades, guidelines for the on-demand treatment of hereditary angioedema attacks have undergone significant evolution. Early treatment guidelines, such as the Canadian 2003 International Consensus Algorithm, often gated on-demand treatment by attack location and/or severity. Pivotal trials for on-demand injectable treatments (plasma-derived C1 esterase inhibitor, icatibant, ecallantide [United States only], and recombinant human C1 esterase inhibitor), which were approved in the United States and the European Union between 2008 and 2014, were designed accordingly. Subsequent post hoc analyses of clinical trial data alongside real-world evidence led to a paradigm shift. In 2013, the US Hereditary Angioedema Association guidelines recommended that all attacks, irrespective of location or severity, be considered for treatment as early as possible after onset to minimize morbidity and mortality. This approach remains the cornerstone of current treatment guidelines and has shaped the design of recent clinical trials, such as those for the investigational agents, oral plasma kallikrein inhibitor sebetralstat and oral bradykinin B2 receptor antagonist deucrictibant. This narrative review discusses the evolution of on-demand treatment guidelines, the clinical trial and real-world data that prompted significant revisions, and the subsequent changes to trial designs introduced to facilitate guideline compliance.

A human centred innovative approach based on persona in hereditary angioedema

BACKGROUND

Hereditary Angioedema (HAE) due to C1-inhibitor deficiency (C1INH) is a rare condition, clinically characterised by recurrent swelling. The unpredictability of attacks affects the patients' quality of life (QoL). HAE patients and their families have vast unmet physical, psychological, and social needs. A human-centred design (HCD) approach to describing the needs of different user types is to utilise personas, a data-driven narrative tool for communicating user archetypes that capture the individuals' attitudes, goals, and behaviours. The aim of this study was to create and analyse personas based on HAE patients' and their caregivers' interviews. Semi-structured interviews were conducted through anthropological conversations with patients, patient-caregivers (double role of patient and caregiver), and non-affected caregivers. Qualitative and quantitative insights from analyses formed the basis to create personas.

RESULTS

We enrolled 17 subjects: 15 patients (6 of them were patient-caregivers) and 2 non-affected caregivers. The mean age of participants was 50.3 ± 14.4 years. Eight patients were on treatment with prophylactic therapy. The mean percentage score of Angioedema Quality of Life (AE-QoL) for HAE patients was 19.8 ± 12.0. Six personas were identified describing the participants' personal history, disease management, and needs: four personas referred to patients, one to patient-caregivers, and one non-affected caregiver personas were identified. Across patient personas, the most expressed needs were psychological support and better awareness amongst healthcare professionals. Caregivers, on their side, desired better information about the disease, including the latest therapies, and higher awareness within the community.

CONCLUSION

A Human Centred Innovative Approach Based on Persona extends beyond the physical symptoms to encompass the psychological and social aspects of the individual's well-being also including the family in the evaluation.

Epidemiology, economic, and humanistic burden of hereditary angioedema: a systematic review

BACKGROUND

This systematic study aims to assess the global epidemiologic, economic, and humanistic burden of illness associated with all types of hereditary angioedema.

METHODS

A systematic search for articles reporting the epidemiologic, economic, and humanistic burden associated with patients with HAE was conducted using English and Chinese literature databases from the inception to May 23, 2022. The selected studies were assessed for their quality and risk of bias. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and registered with the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022352377).

RESULTS

In total, 65 articles that met the search inclusion criteria reported 10,310 patients with HAE, of whom 5861 were female patients. Altogether, 4312 patients (81%) and 479 patients (9%) had type 1 and type 2 HAE, respectively, whereas 422 patients (8%) had HAE-normal C1-INH. The overall prevalence of all types of HAE was between 0.13 and 1.6 cases per 100,000. The mean or median delay from the first onset of a symptom of HAE to confirmed diagnosis ranged from 3.9 to 26 years. The estimated risk of death from asphyxiation was 8.6% for patients with HAE. Hospitalization, medication, unnecessary surgeries, doctor visits, specialist services, and nursing costs are direct expenses that contribute to the growing economic burden. The indirect cost accounted mostly due to missing work ($3402/year) and loss of productivity ($5750/year). Furthermore, impairment of QoL as reported by patient-reported outcomes was observed. QoL measures identified depression, anxiety, and stress to be the most common symptoms for adult patients and children.

CONCLUSION

This study highlights the importance of early diagnosis and the need for improving awareness among health care professionals to reduce the burden of HAE on patients and society.

An Overview of Hereditary Angioedema for the Primary Care Physician

Hereditary angioedema is a rare autosomal dominant condition characterized by episodes of swelling of the upper airway, intestines, and skin. The disorder is characterized by deficiency in C1 esterase inhibitor (C1-INH) or a decrease in functional C1-INH. Treatment options include on demand therapy (treatment of acute attacks), long-term prophylaxis, and short-term prophylaxis. Corticosteroids, epinephrine, and antihistamines are not effective for this form of angioedema. The high mortality in patients undiagnosed underscores a need for broader physician awareness to identify these patients and initiate therapy.

Hereditary angioedema in Spain: medical care and patient journey

BACKGROUND

Hereditary angioedema due to C1 inhibitor deficiency (HAE-C1INH) is a genetic rare disease characterized by recurrent, transient and unpredictable episodes of cold, non-pruriginous oedema without associated urticaria. The characteristics of the disease have a considerable impact on the quality of life of patients. The aim of this study was to increase understanding of the patient journey of HAE in Spain.

METHODS

A multidisciplinary committee of 16 HAE experts (allergy, immunology, emergency department, hospital pharmacy and nursing) and 3 representatives of the Spanish Hereditary Angioedema Patient Association (AEDAF) who were patients or caregivers participated in the study. A review of the publications on HAE treatment was performed. Semi-structured interviews were performed to HAE experts, patients, or caregivers. Three meetings with the experts, patients and caregivers were held to share, discuss, and validate data obtained from literature and interviews and to build the model.

RESULTS

Throughout the project, the patient journey has been drawn up, dividing it into the stages of pre-diagnosis, diagnosis and treatment/follow-up. Some areas for improvement have been identified. Firstly, there is a need to enhance awareness and training on HAE among healthcare professionals, with a particular emphasis on primary care and emergency department personnel. Secondly, efforts should be made to minimize patient referral times to allergy/immunology specialists, ensuring timely access to appropriate care. Thirdly, it is crucial to encourage the study of the relatives of diagnosed patients to early identify potential cases. Fourthly, equitable access to self-administered treatments should be ensured, facilitated by systems that enable medication delivery at home and proper education and training for patients. Equitable access to long-term prophylactic treatment should also be prioritized for all patients in need. To standardize HAE management, the development of consensus guidelines that reduce variability in clinical practice is essential. Lastly, promoting research studies to enhance knowledge of the disease and align its treatment with new developments in the healthcare field should be encouraged.

CONCLUSIONS

The knowledge of the patient journey in HAE allowed us to identify improvement areas with the final aim to optimize the disease management.

Urticaria

The relevance of the disease is due to its prevalence ― for acute urticaria up to 20% with predominance in the paediatric population, for chronic spontaneous urticaria up to 0.5–5% of the population. The course of the disease is characterised by unpredictability of prognosis of duration, effectiveness of standard therapy, serious impact on the quality of life of the patient, his relatives, the burden on health authorities. The lack of accurate understanding of the mechanisms of disease development, a wide range of pathogenetic treatment complicates the possibility of rapid achievement of drug remission. The clinical Recommendations contain up-to-date information on epidemiology, pathogenesis, clinical picture, differential diagnosis, possibilities of examination and stage treatment, including immunobiological therapy. The procedure of medical care, prophylaxis and dispensary observation, criteria for assessing the quality of patient management and supporting material, including questionnaires to assess the severity of the condition and the effectiveness of treatment are outlined. Clinical recommendations on urticaria are intended for practicing physicians of all specialities, students, teachers of medical schools, residents, postgraduates and researchers.

An expert panel's review on patients with hereditary angioedema switching from attenuated androgens to oral prophylactic therapy

Background: Hereditary angioedema (HAE) is a rare condition marked by swelling episodes in various body parts, including the extremities, upper airway, face, intestinal tract, and genitals. Long-term prophylaxis (LTP), prescribed to control recurring HAE attacks, is integral to its management. Previously, attenuated androgens (AAs) were the only oral LTP options. However, in 2020, berotralstat, an oral plasma kallikrein inhibitor, was approved in the United States. A 2018 survey of adults with HAE type I or type II showed that almost all the patients who used prophylactic HAE medication preferred oral treatment (98%) and felt that it fit their lifestyle better than injectable treatment (96%). Still, guidelines lack consensus on transitioning patients from AAs to alternative oral prophylactic therapy. Objective: This paper aims to share expert insights and patient feedback on transitioning from AAs to berotralstat, an alternative oral prophylactic therapy, from the perspective of clinicians with extensive experience in treating patients with HAE. Methods: A panel of five HAE specialists convened for a virtual half-day roundtable discussion in April 2023. Results: Discussions about transitioning from AAs to berotralstat were prompted by routine consultations, patient inquiries based on independent research, ineffective current treatment, or worsening AA-related adverse effects. For patients who switched from AAs, the physicians reported that the decision was influenced by the alternative therapy's ability to prevent HAE attacks, its safety, and the once-daily administration schedule. All expert panel members identified fewer AA-related adverse effects; better quality of life; and less severe, shorter, and less frequent HAE attacks as clinical or patient goals they hoped to achieve through the treatment switch. Conclusion: The emergence of new, highly specific LTP drugs for HAE calls for the development of comprehensive recommendations and guidelines for transitioning from AAs to alternative oral prophylactic therapy. The expert panel highlighted key factors to consider during the development of such guidelines.

Pathophysiology of bradykinin and histamine mediated angioedema

Angioedema is characterized by swelling localized to the subcutaneous and submucosal tissues. This review provides an overview of angioedema, including the different types, triggers, and underlying pathophysiologic mechanisms. Hereditary and acquired angioedema are caused by dysregulation of the complement and kinin pathways. In contrast, drug-induced and allergic angioedema involve the activation of the immune system and release of vasoactive mediators. Recent advances in the understanding of the pathophysiology of angioedema have led to the development of targeted therapies, such as monoclonal antibodies, bradykinin receptor antagonists, and complement inhibitors, which promise to improve clinical outcomes in patients with this challenging condition. To accurately diagnose and manage angioedema, an understanding of this condition's complex and varied pathophysiology is both necessary and critical.

How Does Pregnancy and Type of Delivery Affect the Clinical Course of Hereditary Angioedema?

INTRODUCTION

Knowledge on the clinical course of hereditary angioedema (HAE) during pregnancy, delivery, and breastfeeding is very limited. In this study, we aimed to evaluate the course of HAE during these periods.

METHODS

The HAE attacks C1-INH prophylaxis before and during pregnancy and during breastfeeding, and the delivery types were retrospectively determined. The severity of attacks was assessed by a 10-point Visual Analogue Scale (VAS).

RESULTS

We evaluated 88 pregnancies in 48 HAE patients among whom 20 were primiparous. Among those who had a HAE diagnosis during pregnancy (n = 34), the median attack numbers before pregnancy, during pregnancy, breastfeeding, and after breastfeeding were 17, 39, 24, and 14 (before pregnancy vs. pregnancy, p < 0.001; during pregnancy vs. breastfeeding, p = 0.001). The mean VASs (SD) were 6.59 (1.82), 8.33 (1.58), 7.32 (1.66), and 6.95 (1.90) (before pregnancy vs. pregnancy, p < 0.001; during pregnancy vs. breastfeeding, p = 0.016), respectively. Among those who received a HAE diagnosis after pregnancy (n = 54), the number (59.3%) and the severity (60%) of HAE attacks were high in pregnancy. 47 of the deliveries were normal vaginal delivery (NVD). Regional anesthesia was applied in 8 NVDs. 20 of caesarean deliveries were performed under general anesthesia, and 21 were under spinal anesthesia. Lowest numbers of attacks were found in patients who did not receive anesthesia during NVD (p = 0.001).

CONCLUSION

The course of HAE can be worse during pregnancy and breastfeeding. NVD is related to fewer HAE attacks and prophylaxis with C1-INH during NVD is not necessary to prevent a HAE attack.

Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema

Angioedema is a well-recognized and potentially lethal complication of angiotensin-converting enzyme inhibitor (ACEi) therapy. In ACEi-induced angioedema, bradykinin accumulates due to a decrease in its metabolism by ACE, the enzyme that is primarily responsible for this function. The action of bradykinin at bradykinin type 2 receptors leads to increased vascular permeability and the accumulation of fluid in the subcutaneous and submucosal space. Patients with ACEi-induced angioedema are at risk for airway compromise because of the tendency for the face, lips, tongue, and airway structures to be affected. The emergency physician should focus on airway evaluation and management when treating patients with ACEi-induced angioedema.

Hereditary Angioedema

Hereditary angioedema (HAE) is a rare autosomal dominant genetic disorder that usual results from a decreased level of functional C1-INH and clinically manifests with intermittent attacks of swelling of the subcutaneous tissue or submucosal layers of the respiratory or gastrointestinal tracts. Laboratory studies and radiographic imaging have limited roles in evaluation of patients with acute attacks of HAE except when the diagnosis is uncertain and other processes must be ruled out. Treatment begins with assessment of the airway to determine the need for immediate intervention. Emergency physicians should understand the pathophysiology of HAE to help guide management decisions.

A multicenter chart review of patient characteristics, treatment, and outcomes in hereditary angioedema: unmet need for more effective long-term prophylaxis

BACKGROUND

Hereditary angioedema (HAE) is a rare disease characterized by unpredictable, recurring subcutaneous or submucosal swelling. Without effective therapy, HAE can negatively impact patients' quality of life. Management of HAE includes on-demand treatment of attacks and short- and long-term prophylaxis (LTP) to prevent attacks. Newer therapies may be more tolerable and effective in managing HAE; however, therapies such as androgens are still widely used in some countries owing to their relative ease of access and adequate disease control for some patients. This study evaluated the characteristics, treatment patterns, clinical outcomes, and healthcare resource utilization of a multinational cohort of patients with HAE, with a focus on understanding reasons for recommending or discontinuing available therapies.

METHODS

A retrospective chart review was conducted at 12 centers in six countries and included data from patients with HAE type 1 or 2 who were ≥ 12 years of age at their first clinical visit. The relationship between LTP use and attack rates was evaluated using a multivariable Poisson regression model. Data were collected between March 2018 and July 2019.

RESULTS

Data from 225 patients were collected (62.7% female, 86.2% White, 90.2% type 1); 64.4% of patients had their first HAE-related visit to the center prior to or during 2014. Treatment patterns varied between countries. Overall, 85.8% of patients were prescribed on-demand treatment and 53.8% were prescribed LTP, most commonly the androgen danazol (53.7% of patients who used LTP). Plasma-derived C1 inhibitor (Cinryze^®) was used by 29.8% of patients for LTP. Patients who received LTP had a significantly lower rate of HAE attacks than patients who did not receive any LTP (incidence rate ratio (95% confidence interval) 0.90 (0.84-0.96)). Androgens were the most commonly discontinued therapy (51.3%), with low tolerability cited as the most frequent reason for discontinuation (50.0%).

CONCLUSIONS

Overall, findings from this study support the use of LTP in the prevention of HAE attacks; a lower rate of attacks was observed with LTP compared with no LTP. However, the type of LTP used varied between countries, with tolerability and accessibility to specific treatments playing important roles in management decision-making.

Phenotypic and Genotypic Characterization of Hereditary Angioedema in Saudi Arabia

Hereditary angioedema (HAE) is a potentially life-threatening autosomal dominant disorder affecting roughly 1:50,000 individuals. It is commonly characterized by swelling of the larynx, gastrointestinal tract, extremities, and skin. There is growing genetic heterogeneity associated with this disease but more than 95% of mutations are found in SERPING1, the gene which encodes complement 1 inhibitor (C1-INH). HAE cohorts from several populations have been published but no large scale study has been reported from the Arab world to date. Here we document the clinical and genetic findings of HAE patients from a single Saudi institution, which is a major referral center at the national level. A total of 51 patients across 17 unrelated families were recruited including two large multi-generational families, of which one contained an in-frame exonic deletion that was resolved through MLPA. Two cases were negative for all the genes we tested (including F12, PLG, ANGPT1, MYOF, KNG1, and HS3ST6). The predominant HAE subtype in our cohort was type I, at 76%. We were able to uncover a mutation in 49 patients (96%). No type III (normal C1-INH) patients were encountered in the clinic, suggesting that this subtype does not play a major role in HAE pathogenesis in Saudi Arabia. Additionally, the existence of four patients with consistently normal complement 4 (C4) levels alongside abnormal C1-INH profiles highlights the utility of dual screening for both proteins in suspected patients.

Hereditary Angioedema

Hereditary angioedema is a rare autosomal dominant condition characterized by episodes of swelling of the upper airway, intestines, and skin. The disorder is characterized by deficiency in C1 esterase inhibitor (C1-INH) or a decrease in functional C1-INH. Treatment options include on demand therapy (treatment of acute attacks), long-term prophylaxis, and short-term prophylaxis. Corticosteroids, epinephrine, and antihistamines are not effective for this form of angioedema. The high mortality in patients undiagnosed underscores a need for broader physician awareness to identify these patients and initiate therapy.

Consensus on diagnosis and management of Hereditary Angioedema in the Middle East: A Delphi initiative

Background

Hereditary angioedema (HAE), a potentially life-threatening genetic disorder due to C1 inhibitor deficiency in most cases, is characterized by sudden and/or recurrent attacks of angioedema (subcutaneous/submucosal swellings). The global World Allergy Organization (WAO)/European Academy of Allergy and Clinical Immunology (EAACI) International guideline for HAE management is comprehensive, but the implementation of this guideline may require regional adaptation considering the diversity in disease awareness, type of medical care systems, and access to diagnostics and treatment. The aim of this Delphi initiative was to build on the global guideline and provide regional adaptation to address the concerns and specific needs in the Middle East.

Methods

The Consensus panel comprised 13 experts from the Middle East (3 from the United Arab Emirates, 3 from Saudi Arabia, 2 from Lebanon, 2 from Kuwait, 2 from Oman and 1 from Qatar) who have more than 2 decades of experience in allergy and immunology and are actively involved in managing HAE patients. The process that was carried out to reach the consensus recommendation included: 1.) A systematic literature review for articles related to HAE management using Ovid MEDLINE. 2.) The development of a questionnaire by an internationally acclaimed expert, with 10 questions specific to HAE management in the Middle East. 3.) Experts received the questionnaire via email individually and their answers were recorded (email/interview). 4.) A virtual consensus meeting was organized to discuss the questionnaire, make amends if needed, vote, and achieve consensus.

Results

The questionnaire comprised 10 questions, each with 2 or more statements/recommendations on which the regional experts voted. A consensus was reached based on a 70% agreement between the participants. The key highlights include: 1) HAE experts in the Middle East emphasized the importance of a positive family history for arriving at a diagnosis of HAE. 2) The number of episodes per month or per 6-month period and severity should be used, together with other markers, to determine the need for prophylaxis. 3) Disease status should be monitored by periodic visits and the use of patient-reported outcome measures such as the angioedema activity score and the angioedema control test. 4) Attenuated androgens and tranexamic acid may be considered for long-term prophylaxis, if lanadelumab, C1-Inhibitor or berotralstat are not available.

Conclusion

This consensus recommendation may help to educate healthcare practitioners in the Middle East and unify their approach to the diagnosis and management of HAE.

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.

A case of acquired angioedema

ABSTRACT

Acquired angioedema is a rare disorder characterized by nonurticarial angioedema secondary to deficiency or altered activity of C1-esterase inhibitor protein. This article describes a patient whose recurrent angioedema was initially diagnosed as angiotensin-converting enzyme (ACE) inhibitor-induced angioedema. However, after further testing, she was diagnosed with acquired angioedema and subsequently treated with a synthetic bradykinin B2-receptor antagonist.

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.

Pediatric Emergency Department Management of C1 Inhibitor Deficiency

INTRODUCTION

C1 inhibitor deficiency is a rare, potentially life-threatening syndrome. Acute attacks of angioedema may occur at any time, so the emergency department (ED) constitutes an indispensable component of its care.

AIM

To describe the reasons for consultation by children with C1 inhibitor deficiency at the ED, as well as its management and complications.

PATIENTS AND METHODS

This is a longitudinal retrospective study conducted in a pediatric ED of a tertiary care hospital in Madrid. The study includes children with C1 inhibitor deficiency, aged 0 to 16 years, who had consulted the ED for whatever reason, over a span of 9 years (2011-2020). Analyzed data include the following: age, sex, type of disease, reason for query, complementary examinations, established diagnosis, treatment, number of visits to the ED, length of ED stay, and admissions.

RESULTS

Sixteen patients, amounting a total of 83 ED visits, were analyzed. Fifty-six percent were boys, and the median age was 6.9 years (5 months to 15.9 years). The median and mean of number of visits to the ED per patient was 2 (1-22) and 5.2 ± 6.11, respectively. There were 85.5% of the ED visits initially attributed to acute angioedema attacks. Additional tests were conducted in 30.1%, and 31.3% required C1 inhibitor concentrate. Three episodes required hospital admission (3.6%), and there were no complications. The stay in the ED was longer for patients who needed specific intravenous treatment.

CONCLUSIONS

C1 inhibitor deficiency is a rare disease that may require ED care. The main reasons for ED visits were respiratory problems, and the main location of the acute attacks of angioedema were abdominal and cutaneous. Almost one third of the ED visits needed specific treatment, resulting in longer stays. A proper management in the ED and the specific treatment with C1 inhibitor concentrate were effective in 96.2% of the acute attacks of angioedema. Knowledge of this disease in the ED is key to prevent complications.

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.

Hereditary Angioedema: Diagnostic Algorithm and Current Treatment Concepts

Hereditary angioedema (HAE) is an uncommon disorder with a global prevalence of approximately 1 in 10,000 to 1 in 50,000 population. This disease is grossly underrecognized in India because of lack of awareness and/or lack of diagnostic facilities. Clinical manifestations include swelling over face, eyes, lips, hands, feet, and genitals, abdominal pain, and life-threatening laryngeal edema. HAE should be suspected in all patients who present with angioedema without wheals and who do not respond to antihistamines and/or steroids. C1 levels, C1-INH levels, and C1-INH function should be checked in all patients suspected to have HAE. C1q levels should be assessed in patients with suspected autoimmune-mediated acquired angioedema. Management of HAE constitutes the treatment of acute attack and short-term and long-term prophylaxis. Because of lack of all first-line recommended medications, the management of HAE in India is a challenging task. Patients are managed using fresh frozen plasma (acute treatment), tranexamic acid, and attenuated androgens (prophylaxis). Even though attenuated androgens have been shown to be effective in the prevention of attacks of HAE, the side effect profile especially in children and in females is a serious concern. Hence, the treatment needs to be individualized considering the risk-benefit ratio of long-term prophylaxis. In this review, we provide an overview of diagnostic strategy for patients with HAE and the current treatment concepts with emphasis on currently available treatment options in resource-constrained settings.

Anesthetic management of a patient with acquired angioedema submitted to broncofibroscopy: a case report

Acquired angioedema with C1 inhibitor deficiency (AAE-C1INH) is a very rare condition of bradykinin-mediated angioedema. One of its major complications is potentially life-threatening, laryngeal edema. We report a 53-year-old woman with AAE-C1INH proposed for an elective broncofibroscopy. The direct stimulation caused by broncofibroscopy poses a high risk of angioedema, thus presenting an anesthetic challenge. Due to the risk of death, it is essential to adopt preventive measures. Short-term prophylaxis was performed, and the acute treatment was readily available. A well-structured multidisciplinary periprocedural plan makes it possible to safely approach the airway, in a remote area of the hospital.

Hereditary Angioedema

Hereditary angioedema (HAE) is a rare autosomal dominant genetic disorder that usual results from a decreased level of functional C1-INH and clinically manifests with intermittent attacks of swelling of the subcutaneous tissue or submucosal layers of the respiratory or gastrointestinal tracts. Laboratory studies and radiographic imaging have limited roles in evaluation of patients with acute attacks of HAE except when the diagnosis is uncertain and other processes must be ruled out. Treatment begins with assessment of the airway to determine the need for immediate intervention. Emergency physicians should understand the pathophysiology of HAE to help guide management decisions.

Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema

Angioedema is a well-recognized and potentially lethal complication of angiotensin-converting enzyme inhibitor (ACEi) therapy. In ACEi-induced angioedema, bradykinin accumulates due to a decrease in its metabolism by ACE, the enzyme that is primarily responsible for this function. The action of bradykinin at bradykinin type 2 receptors leads to increased vascular permeability and the accumulation of fluid in the subcutaneous and submucosal space. Patients with ACEi-induced angioedema are at risk for airway compromise because of the tendency for the face, lips, tongue, and airway structures to be affected. The emergency physician should focus on airway evaluation and management when treating patients with ACEi-induced angioedema.

Optimization of care for patients with hereditary angioedema living in rural areas

OBJECTIVE

People living in rural areas of the United States experience greater health inequality than individuals residing in urban or suburban locations and encounter several barriers to obtaining optimal health care. Health disparities are compounded for patients with rare diseases such as hereditary angioedema (HAE), an autosomal dominant genetic disorder characterized by recurrent, severe abdominal pain and lifethreatening oropharyngeal/laryngeal swelling. The objective of this review is to explore the challenges of managing HAE patients in rural areas and suggest possible improvements for optimizing care.

DATA SOURCES

PubMed was searched for articles on patient care management, treatment challenges, rural health, and HAE.

STUDY SELECTIONS

Relevant articles were selected and reviewed.

RESULTS

Challenges in managing HAE in the rural setting were identified including obtaining a diagnosis of HAE, easy access to a physician with expertise in HAE, continuity of care, availability of telemedicine services, access to approved HAE therapies, patient education, and economic barriers to treatment. Ways to improve HAE patient care in rural areas include health care provider recognition of the undiagnosed HAE patient, development of individualized management plans, expansion of telemedicine, effective care at the local level, appropriate access to HAE medication, and increased awareness of patient support and advocacy groups.

CONCLUSION

For HAE patients living in rural areas, optimal care is complicated by health disparities. Given the scarcity with which these topics have been covered in the literature to date, it is intended that this article will serve as the impetus for a range of further initiatives focused on improving access to care.

Acquired C1-inhibitor deficiency due to splenic marginal zone lymhoma: Case Report

We present the case of a 67-year-old woman who suffered recurrent episodes of angioedema of the face and larynx. After thorough biochemical investigations, an acquired deficiency of C1-INH was suspected. To evaluate a potential underlying malignancy, a whole-body FDG-PET/CT was performed and showed solely a marked splenomegaly pointing towards a splenic marginal zone lymphoma, which was confirmed by pathological examination.With this case, we discuss the pathophysiology, diagnosis and management of recurrent acquired angioedema attacks as the first presentation of an underlying lymphoproliferative disease.

Acquired angioedema in B cell lymphoproliferative disease: A retrospective case series

Acquired angioedema due to C1-inhibitor (C1-INH) deficiency (AAE-C1-INH) is rare and is associated with underlying lymphoproliferative diseases. C1-INH deficiency may be due to neoplastic over-consumption of C1-INH and the generation of anti-C1-INH autoantibodies. Uncovering an occult malignancy can lead to earlier oncology referral and improvement of angioedema after treatment of the underlying lymphoproliferative disorder. We characterized seven patients with C1-INH-AAE that highlights the importance of recognizing the association between C1-INH-AAE and underlying malignancy. In acute attacks, patients may be resistant to C1-INH therapy due to the presence of anti-C1-INH autoantibodies or rapid complement consumption, and may respond better to icatibant or ecallantide, which directly affect bradykinin. Treatment of the underlying malignancy also improves AAE-C1-INH symptoms and supports the role of lymphoproliferative B cells in AAE-C1-INH pathophysiology. Monitoring levels of C4, C1-INH function and level, and C1q may be predictive of AAE-C1-INH control and be used as surrogates for treatment efficacy. With close monitoring, low-dose danazol can be effective for long-term prophylaxis. Annual evaluation in AAE-C1-INH is recommended if an underlying malignancy is not found, as angioedema may precede the development of malignancy by several years. Our single-center study has aided in standardization of comprehensive AAE-C1-INH diagnosis, treatment, and monitoring strategies towards future therapeutic clinical trials.

National Audit of a Hereditary and Acquired Angioedema Cohort in New Zealand

BACKGROUND

HAE leads to significant morbidity and mortality from unpredictable intermittent peripheral, abdominal and laryngeal swelling. Access to appropriate healthcare and effective therapies which can prevent and treat attacks, reduce the suffering and greatly improve quality of life. Although treatments such as C1 inhibitor (Berinert®), and Icatibant® are available in New Zealand (Aotearoa), there is no published data available on their use.

AIMS

This study presents a national audit of Hereditary Angioedema (HAE) and Acquired Angioedema (AAE) in 2019.

RESULTS

The total number of known adult (48) and children (3) HAE and Acquired Angioedema (3) patients is 54. Of these, 41/ 54 (75%) of HAE and AAE patients were recruited to the audit. Icatibant® has been available for treatment of acute HAE attacks since 2016, and is now used in 73% of HAE patients. Icatibant® is also used by patients for laryngeal attacks in the community, who may not then present to hospital. Androgens are used in half of the patients as prophylaxis but 33% of the latter were identified as not having regular liver ultrasound screening. Tranexamic acid is used as prophylaxis in one fifth of patients. Participants have had 40 children, half of whom may be affected. Three have been diagnosed with HAE, suggesting that the majority have not yet been tested.

CONCLUSIONS

Corrective actions arising from this audit will improve our capacity to provide long term care for HAE patients and their families. This article is protected by copyright. All rights reserved.

Hereditary angioedema

A 14-year-old African American female presented to the emergency department with spontaneous, sudden-onset lip swelling for 1 h. On examination, there was significant water-bag edema of the upper lip extending to the philtrum and premaxilla. Nasopharyngeal laryngoscopy revealed a patent airway without edema. She was initiated on intravenous dexamethasone, famotidine, and diphenhydramine, after which her edema improved but did not resolve. She was subsequently transferred to a local pediatric hospital and upon further testing she was found to have a C1 esterase inhibitor de novo gene mutation. Angioedema causes localized, non-pitting edema of the dermis, subcutaneous and submucosal tissue, and often manifests in the lips, face, mouth, and throat. Signs of laryngeal involvement include change in voice, stridor, dysphagia, and dyspnea. When laryngeal edema is present, it may necessitate definitive airway management and patients should be monitored in the intensive care unit.

Mitigating Disparity in Health-care Resources Between Countries for Management of Hereditary Angioedema

Hereditary angioedema (HAE) is a rare genetic disorder characterized by recurrent episodes of skin and mucosal edema. The main treatment goal is to enable a “normal life” for all patients. However, due to high costs, there are limited options for the management of HAE in most developing and low-income countries. As a result, most of the recommended first-line treatments are not available. In this review, we attempt to highlight the disparities in health-care resources for the management of patients with HAE amongst different countries. Data was collected from HAE experts in countries who provide tabulated information regarding management and availability of HAE treatments in their countries. We reviewed the two most recent international HAE guidelines. Using India, the world’s second most populous country, as a paradigm for HAE management in lower-income countries, we reviewed the evidence for second-line and non-recommended practices reported by HAE experts. Results suggest significant inequities in provision of HAE services and treatments. HAE patients in low-income countries do not have access to life-saving acute drugs or recently developed highly effective prophylactic medications. Most low-income countries do not have specialized HAE services or diagnostic facilities, resulting in consequent long delays in diagnosis. Suggestions for optimizing the use of limited resources as a basis for future discussion and reaching a global consensus are provided. There is an urgent need to improve HAE services, diagnostics and treatments currently available to lower-income countries. We recommend that all HAE stakeholders support the need for global equity and access to these essential measures.

Hereditary angioedema due to C1 inhibitor deficiency in Belarus: epidemiology, access to diagnosis and seven novel mutations in SERPING1 gene

Background

Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) is a rare disease. Few states in developing countries have an adequate management of HAE, but none of them belongs to the former USSR area. This study analyses data from C1-INH-HAE patients from Belarus.

Methods

Data about clinical characteristics, genetics, access to diagnosis and treatment were collected from 2010 by the Belarusian Research Center for Pediatric Oncology, Hematology and Immunology in Minsk. A questionnaire about attacks, prophylactic (LTP) and on-demand therapy (ODT) was administered to patients.

Results

We identified 64 C1-INH-HAE patients belonging to 26 families, 27 (42.2%) of which were diagnosed in the last 3 years. The estimated minimal prevalence was 1:148,000. Median age at diagnosis was 29 years, with diagnostic delay of 19 years. Thirty-eight patients answered a questionnaire about therapy. Eleven patients did not use any treatment to resolve HAE attacks. Twenty-seven patients underwent ODT: 9 with appropriate treatments, and 18 with inappropriate treatments. Nine patients used LTP with attenuated androgens and 1 with tranexamic acid. Thirty-two patients answered a questionnaire about attacks and triggers: 368 angioedema attacks were reported, with an average of 10 attacks per year. We found 24 different SERPING1 variants: 9 missenses, 6 in splice sites, 6 small deletions, 2 nonsense, 1 large deletion; 7 have not been previously described. De novo variants were found in 11 patients.

Conclusions

C1-INH-HAE diagnosis and management in Belarus is improved as seen from the high number of new diagnosis in the last 3 years. Next steps will be to reduce the diagnostic delay and to promote the LTP and ODT.

Recognition, Evaluation, and Management of Pediatric Hereditary Angioedema

ABSTRACT

Hereditary angioedema (HAE) is a rare, often underrecognized genetic disorder caused by either a C1 esterase inhibitor deficiency (type 1) or mutation (type 2). This leads to overproduction of bradykinin resulting in vasodilation, vascular leakage, and transient nonpitting angioedema occurring most frequently in the face, neck, upper airway, abdomen, and/or extremities. Involvement of the tongue and laryngopharynx has been associated with asphyxiation and death. Hereditary angioedema is an autosomal-dominant condition; therefore, there is a 50% chance an offspring will inherit this disorder. Any patient presenting with isolated angioedema should be screened with a C4 measurement, as 25% of cases have no family history of HAE. All patients with HAE will have a functional deficiency of C1 esterase inhibitor. Contributors that delay the diagnosis of HAE include recognition delay by clinicians who confuse this condition with histaminergic angioedema, the disease's varied presentations, and limitations to timely testing. Pediatric emergency clinicians should be knowledgeable about how to distinguish between bradykinin- and histamine-mediated angioedema, as there are significant differences in the diagnostic testing, treatment, and clinical response between these 2 different conditions. Evidence indicates that early diagnosis and treatment of HAE reduces morbidity and mortality. Clinician recognition of the mechanistically different problems will ensure patients are appropriately referred to an expert for outpatient management.

Quantitative multiplex profiling of the complement system to diagnose complement-mediated diseases

Objectives

Complement deficiencies are difficult to diagnose because of the variability of symptoms and the complexity of the diagnostic process. Here, we applied a novel ‘complementomics’ approach to study the impact of various complement deficiencies on circulating complement levels.

Methods

Using a quantitative multiplex mass spectrometry assay, we analysed 44 peptides to profile 34 complement proteins simultaneously in 40 healthy controls and 83 individuals with a diagnosed deficiency or a potential pathogenic variant in 14 different complement proteins.

Results

Apart from confirming near or total absence of the respective protein in plasma of complement‐deficient patients, this mass spectrometry‐based profiling method led to the identification of additional deficiencies. In many cases, partial depletion of the pathway up‐ and/or downstream of the absent protein was measured. This was especially found in patients deficient for complement inhibitors, such as angioedema patients with a C1‐inhibitor deficiency. The added value of complementomics was shown in three patients with poorly defined complement deficiencies.

Conclusion

Our study shows the potential clinical utility of profiling circulating complement proteins as a comprehensive read‐out of various complement deficiencies. Particularly, our approach provides insight into the intricate interplay between complement proteins due to functional coupling, which contributes to the better understanding of the various disease phenotypes and improvement of care for patients with complement‐mediated diseases.

Clinical presentation of hereditary angioedema

Hereditary angioedema (HAE) is a rare, autosomal dominant disease caused by a deficiency in the C1-inhibitor protein. It is characterized by recurrent episodes of nonpruritic, nonpitting, subcutaneous or submucosal edema that typically involves the extremities or the gastrointestinal tract. However, the genitourinary tract, face, oropharynx, and/or larynx may be affected as well. Symptoms often begin in childhood, worsen at puberty, and persist throughout life, with unpredictable severity. Patients who are untreated may have frequent attacks, with intervals that can range from every few days to rare episodes. Minor trauma and stress are frequent precipitants of swelling episodes, but many attacks occur without clear triggers. HAE attacks may be preceded by a prodrome and/or be accompanied by erythema marginatum. The swelling typically worsens over the first 24 hours, before gradually subsiding over the subsequent 48 to 72 hours. Although oropharyngeal swelling is less frequent, more than half of patients have had at least one episode of laryngeal angioedema during their lifetime. Attacks may start in one location and spread to another before resolving. HAE attacks that involve the abdomen or oropharynx have been associated with significant morbidity and mortality. Abdominal attacks can cause severe abdominal pain, nausea, and vomiting. Bowel sounds are often diminished or silent, and guarding and rebound tenderness may be present on physical examination. These findings may lead to unnecessary abdominal imaging and procedures. Fluid shifts into the interstitial space or peritoneal cavity can cause clinically significant hypotension. Laryngeal edema poses the greatest risk for patients with HAE. Although prompt diagnosis and treatment improves outcomes, the variable presentation of HAE can make it difficult to diagnose.

Hereditary angioedema: Report of the dental treatment of 12 Brazilian patients

OBJECTIVE

The aim of this study was to report on clinical experience in Brazil in the dental treatment and the oral conditions of a group of patients with hereditary angioedema (HAE).

STUDY DESIGN

The study analyzed demographic data, type of HAE, intensity of attacks, long-term and short-term prophylaxis, dental procedures, and occurrence of crises after the procedures were performed. Radiographic evaluation of the number of teeth and bone loss was also performed.

RESULTS

Data from 12 patients were collected; most were women, presenting with C1-INH-HAE type I and a history of severe attacks. All patients reported use of regular medications (long-term prophylaxis), mostly attenuated androgens, to prevent/attenuate HAE attacks. These patients had several missing teeth and alveolar bone loss. Tooth extraction was the most common procedure. In half the patients, the procedures had been performed without modification in long-term prophylaxis. The others were treated with an additional prophylaxis protocol (short-term prophylaxis), particularly those who underwent tooth extraction. None of the study patients developed HAE attacks after dental procedures.

CONCLUSION

The occurrence and intensity of a possible HAE attack after dental procedures are unpredictable, but with careful preliminary screening by dental and immunology teams and the use of therapeutic prophylaxis, the risk could be minimized.

US HAEA Medical Advisory Board 2020 Guidelines for the Management of Hereditary Angioedema

Scientific and clinical progress together with the development of effective novel therapeutic options has engendered multiple important changes in the diagnosis and management of hereditary angioedema (HAE). We now update and extend the 2013 United States Hereditary Angioedema Association Medical Advisory Board guidelines for the treatment and management of HAE. The guidelines are based on a comprehensive literature review with recommendations indicating both the strength of our recommendation and the quality of the underlying evidence. Guidelines are provided regarding the classification, diagnosis, on-demand treatment, prophylactic treatment, special considerations for women and children, development of a comprehensive management and monitoring plan, and assessment of burden of illness for both HAE due to C1 inhibitor deficiency and HAE with normal C1 inhibitor. Advances in HAE treatment now allow the development of management plans that can help many patients with HAE lead a normal life. Achieving this goal requires that physicians be familiar with the diagnostic and therapeutic transformations that have occurred in recent years.

The International/Canadian Hereditary Angioedema Guideline

This is an update to the 2014 Canadian Hereditary Angioedema Guideline with an expanded scope to include the management of hereditary angioedema (HAE) patients worldwide. It is a collaboration of Canadian and international HAE experts and patient groups led by the Canadian Hereditary Angioedema Network. The objective of this guideline is to provide evidence-based recommendations, using the GRADE system, for the management of patients with HAE. This includes the treatment of attacks, short-term prophylaxis, long-term prophylaxis, and recommendations for self-administration, individualized therapy, quality of life, and comprehensive care. New to the 2019 version of this guideline are sections covering the diagnosis and recommended therapies for acute treatment in HAE patients with normal C1-INH, as well as sections on pregnant and paediatric patients, patient associations and an HAE registry. Hereditary angioedema results in random and often unpredictable attacks of painful swelling typically affecting the extremities, bowel mucosa, genitals, face and upper airway. Attacks are associated with significant functional impairment, decreased health-related quality of life, and mortality in the case of laryngeal attacks. Caring for patients with HAE can be challenging due to the complexity of this disease. The care of patients with HAE in Canada, as in many countries, continues to be neither optimal nor uniform. It lags behind some other countries where there are more organized models for HAE management, and greater availability of additional licensed therapeutic options. It is anticipated that providing this guideline to caregivers, policy makers, patients, and advocates will not only optimize the management of HAE, but also promote the importance of individualized care. The primary target users of this guideline are healthcare providers who are managing patients with HAE. Other healthcare providers who may use this guideline are emergency and intensive care physicians, primary care physicians, gastroenterologists, dentists, otolaryngologists, paediatricians, and gynaecologists who will encounter patients with HAE and need to be aware of this condition. Hospital administrators, insurers and policy makers may also find this guideline helpful.

Anaesthetic Approach for Patient with Hereditary Angioedema

Hereditary Angioedema (HEA), a disease caused by a mutation in the gene that encodes for the production of the fraction C1 in the complement (C1-INH), is a rare pathology (1/50.000) that causes swelling of the skin and submucosa in various organs, either naturally triggered or provoked by physical and psychological traumas, infections, or by the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and angiotensin-converting enzyme inhibitors (ACEIs). Surgical trauma may spur the HEA crisis, leading to complications such as the swelling of the respiratory tracts and hemodynamic instability. Thus, the pre-surgical approach to HEA patients requires a specific plan that ensures short term prophylaxis, careful intra-operative management, rescue therapy and intensive post-surgery care. We present a report on a video-laparoscopic cholecystectomy approach for a 28-year-old woman diagnosed with asthma and HEA with symptomatic choledocholithiasis. We opted for short-term prophylaxis and immunology with the intravenous application of C1-INH. Ultrasonography imaging showed arterial wall oedema, which could correspond to a manifestation of C1-INH deficiency in the wall of the manipulated arteries during ultrasonography-guided puncture. Once the patient recovered consciousness, she was transferred to the intensive care unit and was discharged on the 6^th day of hospitalisation.

Management of patients with hereditary angio-oedema in dental, oral, and maxillofacial surgery: a review

Hereditary angio-oedema (HEA) is an autosomal dominant, life-threatening genetic disorder that is caused by insufficiency or dysfunction of the C1 esterase inhibitor that develops coincidentally with recurrent oedema in the skin, internal organs, and upper respiratory tract. Increased production of bradykinin secondary to increased plasma kallikrein activity is the primary cause of attacks. Dental procedures cause emotional stress and mechanical trauma and may also initiate attacks. The most feared complication is asphyxiation as a result of laryngeal oedema. Cases that resulted in death after tooth extraction have been reported, so dentists and oral and maxillofacial surgeons should take maximum care in the treatment of patients with HAO, consult with the patient's doctor, and ensure that prophylaxis is given before the procedure. They should work as atraumatically as possible and use procedures to minimise stress. In the event of an attack of HAO, despite all the correct measures having been taken, the procedure should be terminated immediately and treatment of the attack started as soon as possible. The first drugs for the treatment of acute attacks are C1-INH (C1 inhibitor), ecallantide, or icatibant.

Angioedema as a systemic disease

Angioedema is a clinical entity defined as self-limiting edema localized in the deeper layers of the skin and mucosa and lasting for several days. Angioedema can be provoked by bradykinin and/or mast cell mediators, including histamine. Four types of acquired and three types of hereditary angioedema have been identified. The most obvious form of angioedema associated with other systemic disease is acquired angioedema due to C1-inhibitor deficiency. It is characterized by acquired consumption of C1 inhibitor and various underlying disorders, such as multiple myeloma, chronic lymphocytic leukemia, rectal carcinoma, and non-Hodgkin lymphoma. Suspected cases need an accurate differential diagnosis to exclude all other types of acquired and hereditary angioedema.

Evaluation and Management of Angioedema in the Emergency Department

Angioedema is defined by non-dependent, non-pitting edema that affects several different sites and is potentially life-threatening due to laryngeal edema. This narrative review provides emergency physicians with a focused overview of the evaluation and management of angioedema. Two primary forms include histamine-mediated and bradykinin-mediated angioedema. Histamine-mediated forms present similarly to anaphylaxis, while bradykinin-mediated angioedema presents with greater face and oropharyngeal involvement and higher risk of progression. Initial evaluation and management should focus on evaluation of the airway, followed by obtaining relevant historical features, including family history, medications, and prior episodes. Histamine-mediated angioedema should be treated with epinephrine intramuscularly, antihistaminergic medications, and steroids. These medications are not effective for bradykinin-mediated forms. Other medications include C1-INH protein replacement, kallikrein inhibitor, and bradykinin receptor antagonists. Evidence is controversial concerning the efficacy of these medications in an acute episode, and airway management is the most important intervention when indicated. Airway intervention may require fiberoptic or video laryngoscopy, with preparation for cricothyrotomy. Disposition is dependent on patient's airway and respiratory status, as well as the sites involved.

Hereditary Angioedema Type 1 with Recurrent Dizziness

A 41-year-old woman presented with recurrent dizziness. After an attack of dizziness, she felt edematous sensations in her hands. However, according to photographs taken during the attack, the edema on the back of the patient's hands and fingers appeared mild. Laboratory examinations revealed a low C4 and C1 inhibitor (INH) activity. A direct sequencing analysis of C1INH revealed a pathogenic gene mutation. Based on these results, she was diagnosed with hereditary angioedema (HAE) type 1. These findings indicate that HAE can cause recurrent dizziness, and it should therefore be included in the differential diagnosis in patients with recurrent neurologic symptoms, even in the absence of severe edema.