Fresh frozen plasma for on-demand hereditary angioedema treatment in South Africa and Iran

Current and Emerging Therapeutics in Hereditary Angioedema

Angioedema is characterized by transient movement of fluid from the vasculature into the interstitial space leading to subcutaneous or submucosal non-pitting edema. Current evidence suggests that most angioedema conditions can be grouped into 2 categories: mast cell-mediated (previously termed histaminergic) or bradykinin-mediated angioedema. Although effective therapies for mast cell-mediated angioedema have existed for decades, specific therapies for bradykinin-mediated angioedema have more recently been developed. In recent years, rigorous studies of these therapies in treating hereditary angioedema (HAE) have led to regulatory approvals of medication for HAE management thereby greatly expanding HAE treatment options.

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.

Delay in diagnosis is the most important proximate reason for mortality in hereditary angio-oedema: our experience at Chandigarh, India

BACKGROUND

Hereditary angio-oedema (HAE) is a rare autosomal dominant disorder characterized clinically by recurrent episodes of nonpruritic subcutaneous and/or submucosal oedema. Laryngeal oedema is the commonest cause of mortality in patients with HAE. Prior to the availability of first-line treatment options for the management of HAE, mortality was as high as 30%. Mortality has significantly declined in countries where first-line treatment options are available and patients can access these therapies. There is a paucity of literature on the outcomes of patients with HAE in developing countries where availability of and access to first-line treatment options are still a challenge.

OBJECTIVES

To report our experience on mortality in patients with HAE and to report factors associated with the death of these patients.

METHODS

We carried out a record review of all patients diagnosed with HAE between January 1996 and August 2022. Families with HAE who had reported the death of at least one family member/relative from laryngeal oedema were studied in detail.

RESULTS

Of the 65 families (170 patients) registered in the clinic, 16 families reported the death of at least one family member/relative from laryngeal oedema (total of 36 deaths). Of these 16 families, 14 reported that 1 or more family members had experienced at least 1 attack of laryngeal oedema. One patient died during follow-up when she was taking long-term prophylaxis with stanozolol and tranexamic acid, while the remaining 35 patients were not diagnosed with HAE at the time of their death. At the time of death of all 36 patients, at least 1 other family member had symptoms suggestive of HAE, but the diagnosis was not established for the family.

CONCLUSIONS

To our knowledge, this is the largest single-centre cohort of patients with HAE in India reporting mortality data and factors associated with death in these families. The delay in diagnosis is the most important reason for mortality.

Assessment of HAE prophylaxis transition from androgen therapy to berotralstat: A subset analysis of the APeX-S trial

Background

Given the recent approval of oral berotralstat in several countries for hereditary angioedema (HAE) prophylaxis, transition from long-term androgens to berotralstat may occur in clinical practice. The open-label, Phase II APeX-S trial provided an opportunity to assess the safety and effectiveness of berotralstat in patients previously treated with differing durations of androgens and shorter transition periods. Therefore, we examined the safety, effectiveness, and impact on quality of life of berotralstat after prior androgen use in patients from the APeX-S trial. Alanine aminotransferase (ALT) elevations were also examined because of the association with androgen exposure and hepatic function impairment.

Methods

We conducted an analysis of a subset of 39 patients from the APeX-S trial aged ≥12 years with HAE due to C1 inhibitor deficiency (HAE-C1-INH) with prior androgen use who discontinued androgen therapy within <60 days of receiving berotralstat. Patients received daily berotralstat (150 mg) and were divided into subgroups for this analysis based on time between androgen discontinuation and berotralstat commencement (<14 days versus 14 to <60 days).

Results

Berotralstat was generally well tolerated, with nasopharyngitis (21%), upper respiratory tract infection (15%), nausea (15%), diarrhea (15%), and abdominal pain (10%) being the most common adverse events occurring in ≥10% of the total subset. Only 7/145 (5%) of all APeX-S study patients with a prior history of androgen therapy experienced ALT elevations, 6 of which were grade 3 or 4 toxicities. All 7 patients recovered without sequelae and belonged to the subgroup of patients who transitioned <14 days after discontinuing androgens (n = 18). A reduction in monthly attack rate versus Month 1 was observed over 12 months for all patients who transitioned from prior androgen therapy to berotralstat prophylaxis in under 60 days, irrespective of duration of prior androgen therapy or timing of transition (N = 39). Similarly, meaningful patient-reported improvements from both Angioedema Quality of Life Questionnaire and Treatment Satisfaction Questionnaire for Medication scores were achieved, with a sustained benefit shown over the berotralstat treatment period.

Conclusions

Berotralstat treatment led to sustained HAE symptom control irrespective of duration of prior androgen therapy or timing of transition. Most patients safely transitioned from long-term androgens to berotralstat. Although occurring in a small group of patients, liver-related adverse events following berotralstat treatment may be associated with a shorter androgen washout period, but further research is required to confirm this.

Clinical trial registration

NCT03472040. Retrospectively registered March 21, 2018.

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: Diagnosis, Clinical Implications, and Pathophysiology

Hereditary angioedema (HAE) is an autosomal dominant disorder caused by a mutation in the C1 esterase inhibitor gene. HAE affects 1/50,000 people worldwide. Three main types of HAE exist: type I, type II, and type III. Type I is characterized by a deficiency in C1-INH. C1-INH is important in the coagulation complement, contact systems, and fibrinolysis. Most HAE cases are type I. Type I and II HAE result from a mutation in the SERPING1 gene, which encodes C1-INH. Formally known as type III HAE is typically an estrogen-dependent or hereditary angioedema with normal C1-INH activity. Current guidelines now recommend subdividing hereditary angioedema with normal C1 esterase inhibitor gene (HAE-nl-C1-INH formerly known as HAE type III) based on underlying mutations such as in kininogen-1 (HAE-KNG1), plasminogen gene (PLG-HAE), myoferlin gene mutation (MYOF-HAE), heparan sulfate-glucosamine 3-sulfotransferase 6 (HS3ST6), mutation in Hageman factor (factor XII), and in angiopoietin-1 (HAE-ANGPT-1). The clinical presentation of HAE varies between patients, but it usually presents with nonpitting angioedema and occasionally abdominal pain. Young children are typically asymptomatic. Those affected by HAE usually present with symptoms in their early 20s. Symptoms can arise as a result of stress, infection, or trauma. Laboratory testing shows abnormal levels of C1-INH and high levels of bradykinin. C4 and D-dimer levels can also be monitored if an acute HAE attack is suspected. Acute treatment of HAE can include IV infusions of C1-INH, receptor antagonists, and kallikrein inhibitors. Short- and long-term prophylaxis can also be administered to patients with HAE. First-line therapies for long-term prophylaxis also include IV infusion of C1-INH. This review aims to thoroughly understand HAE, its clinical presentation, and how to treat it.

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.

Safety of medications for hereditary angioedema during pregnancy and lactation

INTRODUCTION

Hereditary Angioedema (HAE) attacks show an increased frequency and severity for pregnant and lactating females secondary to the hormonal changes. The diagnosis and management of HAE in pregnant and lactating females pose a challenge for physicians due to the rarity of the disease and the paucity of the data for specific management.

AREAS COVERED

In this manuscript, we discuss the diagnosis and special presentation of HAE types 1 and 2 in pregnant and lactating females, including acute management, short-term prophylaxis, long-term prophylaxis, and drugs that should be avoided. Relevant publications were found through key word search of papers indexed in both Google Scholar and PubMed on 1 July 2022.

EXPERT OPINION

Treatment of HAE in the past has been mainly provided by experts; however, with more medications and an increasing number of patients, knowledge of how to care for HAE patients during pregnancy and lactation is important to review. Despite approval of additional medications in many countries, plasma-derived C1-inhibitor remains the drug of first choice for treatment in this unique population. Additional research is needed to increase safe access to other therapy options. We hope that future clinical studies, registries, and databases will shed additional light on this subject.

Hereditary Angioedema: The Clinical Picture of Excessive Contact Activation

Hereditary angioedema is a rare, genetic disorder characterized by painful, debilitating and potentially life-threatening angioedema attacks in subcutaneous and submucosal tissue. While usually unpredictable, attacks can be provoked by a variety of triggers including physical injury and certain medication and are often preceded by prodromal symptoms. Hereditary angioedema has a profound influence on the patients' lives. The fundamental cause of hereditary angioedema in almost all patients is a mutation in the SERPING1 gene leading to a deficiency in C1-inhibitor. Subsequently, the contact activation cascade and kallikrein-kinin pathway are insufficiently inhibited, resulting in excessive bradykinin production triggering vascular leakage. While C1-inhibitor is an important regulator of the intrinsic coagulation pathway, fibrinolytic system and complement cascade, patients do not have an increased risk of coagulopathy, autoimmune conditions or immunodeficiency disorders. Hereditary angioedema is diagnosed based on C1-inhibitor level and function. Genetic analysis is only required in rare cases where hereditary angioedema with normal C1-inhibitor is found. In recent years, new, highly specific therapies have greatly improved disease control and angioedema-related quality of life. This article reviews the clinical picture of hereditary angioedema, the underlying pathophysiology, diagnostic process and currently available as well as investigational therapeutic options.

Bradykinin-induced angioedema in the emergency department

Background

Acute airway angioedema commonly occurs through two distinct mechanisms: histamine- and bradykinin-dependent. Although they respond to distinct treatments, these two potentially life-threatening states present similarly. Poor recognition of the bradykinin-dependent pathway leads to treatment errors in the emergency department (ED), despite the availability of multiple pharmacologic options for hereditary angioedema (HAE) and other forms of bradykinin-induced angioedema. Here, we consider the pathophysiology and clinical features of bradykinin-induced angioedema, and we present a systematic literature review exploring the effectiveness of the available therapies for managing such cases.

Methods

PubMed searches using ‘emergency’, ‘bradykinin’ and various therapeutic product names identified studies reporting the efficacy of treatments for bradykinin-induced angioedema in the ED setting. In all, 22 studies met prespecified criteria and are analysed here.

Findings

Whereas histamine-induced angioedema has a faster onset and often presents with urticaria, bradykinin-induced angioedema is slower in onset, with greater incidence of abdominal symptoms. Acute airway angioedema in the ED should initially be treated with anaphylactic protocols, focusing on airway management and treatment with epinephrine, antihistamine and systemic steroids. Bradykinin-induced angioedema should be considered if this standard treatment is not effective, despite proper dosing and regard of beta-adrenergic blockade. Therapeutics currently approved for HAE appear as promising options for this and other forms of bradykinin-induced angioedema encountered in the ED.

Conclusion

Diagnostic algorithms of bradykinin-induced angioedema should be followed in the ED, with early use of approved therapies to improve patient 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.

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.

An anesthetic experience of hereditary angioedema type I patient undertook total laparoscopic hysterectomy - A case report

Background

Hereditary angioedema (HAE) is an autosomal dominant disorder. The characteristic of HAE is recurrent angioedema episodes due to low C1 esterase inhibitor (C1-INH) level. HAE symptoms, especially those affecting oropharynx or larynx may develop respiratory distress syndrome due to impaired airway, which can be potentially fatal.

Case

We report a clinical case of a 57 year-old female patient, with type I HAE, scheduled for total laparoscopic hysterectomy under general endotracheal anesthesia, which was done successfully without inducing airway edema. Danazol, which increases liver synthesis of C1- INH, was administered and fresh frozen plasma (FFP), which contained C1-INH, was transfused after induction.

Conclusions

For HAE patients, the greatest concern is that general anesthesia can induces upper airway edema by direct mucosal irritation by the endotracheal tube. The perioperative management should include both prophylactic increase of C1-INH production and on-demand administration of C1-INH or FFP.

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.

Racial and Ethnic Disparities in the Research and Care of Hereditary Angioedema Patients in the United States

BACKGROUND

Hereditary angioedema (HAE) affects all races and both sexes equally. Minority patients are underrepresented in clinical trials and may be at risk for additional disease burden.

OBJECTIVES

To examine racial and ethnic disparities in the research and care of patients with HAE.

METHODS

We conducted a retrospective population-based study using TriNetX Diamond Network. International Classification of Diseases, 10th Revision, Current Procedural Terminology, and RxNorm codes identified patients with HAE. The proportions of White, Black, and Hispanic patients with HAE were contrasted with racial and ethnic distributions of patients with HAE in clinical trials. Lifetime prevalence of mental health disorders and HAE treatments was contrasted among different racial and ethnic groups.

RESULTS

A population-based search identified 2122 patients with HAE. The prevalence of HAE among Black patients (1.64/100,000 patients) mirrored that of White patients (1.47/100,000 patients), whereas there was a lower HAE prevalence among Hispanic patients (0.80/100,000 patients). The demographics of the 1274 patients with HAE included in phase 2/3 clinical trials differed significantly from population-based data with overrepresentation of White patients (89.9% vs 77.9%) and underrepresentation of Black patients (3.8% vs 13.6%) and Hispanic patients (1.3% vs 8.1%). Across the different racial and ethnic groups of patients with HAE, the prevalence of mental health disorders was comparatively higher than among patients without HAE. Whereas depression was equally prevalent across the different HAE racial and ethnic groups, anxiety was more prevalent among White patients.

CONCLUSIONS

Clinical trials for Food and Drug Administration-approved HAE medications underrepresent minority patients. Hereditary angioedema remains underdiagnosed in Hispanic patients. Other than a lower prevalence of anxiety disorders among Black patients relative to White patients, the mental health impact of HAE is equally distributed across the different racial and ethnic groups.

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.

Berotralstat (BCX7353) is a novel oral prophylactic treatment for hereditary angioedema: Review of phase II and III studies

Background: Hereditary angioedema (HAE) is a rare genetic disorder characterized by unpredictable and potentially life-threatening episodes of swelling in various parts of the body. These attacks can be painful and debilitating, and affect a patient's quality of life. Every patient who experiences an attack should be treated with on-demand medication to mitigate attack severity and duration. Many patients with HAE also receive long-term prophylaxis to reduce the frequency and severity of edema episodes. Although long-term prophylaxis reduces the disease burden for patients with HAE, available intravenous and subcutaneous treatments are accompanied by a significant treatment burden because of the logistical, emotional, and physical challenges posed by their long-term parenteral nature. Androgens are an effective oral prophylactic treatment; however, they are associated with significant adverse events and are not suitable for all patients. Thus, the HAE community has expressed interest in the development of alternative oral prophylactic therapies for preventing HAE attacks. Objective: Here, we review the phase II and III clinical data of berotralstat (BCX7353), which was approved by the U.S. Food and Drug Administration in December 2020. Results: Berotralstat is an oral, second-generation, synthetic, small-molecule plasma kallikrein inhibitor taken once daily for the prevention of HAE attacks in patients ages ≥ 12 years. Results from the APeX studies (APeX-1 NCT02870972, APeX-2 NCT03485911, APeX-S NCT03472040, APex-J NCT03873116) demonstrated the efficacy of berotralstat as long-term prophylaxis for patients with HAE, which showed a reduction in the attack rate and on-demand medication usage. Berotralstat was well tolerated, and gastrointestinal treatment-emergent adverse events were generally mild and self-limited. Conclusion: Oral berotralstat is an effective and safe long-term prophylactic treatment for patients with HAE that will provide patients unable to tolerate parenteral therapies with the option of disease control. Berotralstat may be associated with reduced treatment burden compared with injectable therapies, highlighting the importance of patient preference with regard to the administration route of their HAE prophylactic treatment.

Clinical manifestations of hereditary angioedema and a systematic review of treatment options

OBJECTIVE

This study systematically reviews the existing literature on the management of hereditary angioedema (HAE) and provides an update on the clinical presentation and specific therapies.

METHODS

A literature search of PubMed and Embase databases was conducted from start of the database to February 2021. Inclusion criteria included relevant systematic reviews, randomized control clinical trials, prospective and retrospective cohort studies, and outcomes research published in English and available in full-text. Out of 310 candidate articles, a total of 55 articles were included in our study.

RESULTS

The most common genetic form of HAE in up to 85% of cases is caused by low levels of C1 esterase inhibitor (C1-INH) protein, leading to a bradykinin-mediated increase in vascular permeability. During an attack of HAE, abortive treatment with C1-INH replacement is most commonly described, however, icatibant, ecallantide, or fresh frozen plasma are also used. Long-term prophylaxis in the form of C1-INH replacement (subcutaneous or intravenous), monoclonal antibodies targeting plasma kallikrein, attenuated androgens, and transexemic acid should be considered for those who suffer from frequent, severe attacks.

CONCLUSION

Progressively distal involvement of the upper airway, especially the larynx, has been shown to pose an increased risk of asphyxiation and death in the acute presentation of HAE. Evaluation by an otolaryngologist is often sought during the emergent clinical management of HAE; therefore, it is prudent that the consulting physician is well-versed in the prompt recognition, triage of patients, and appropriate treatment modalities.

LEVEL OF EVIDENCE

1A.

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.

Novel SERPING1 gene mutations and clinical experience of type 1 hereditary angioedema from North India

BACKGROUND

There is paucity of literature on long-term follow-up of patients with hereditary angioedema (HAE) from developing countries.

OBJECTIVE

This study was carried out to analyze the clinical manifestations, laboratory features, and genetic profile of 32 patients (21 male and 11 female) from 23 families diagnosed with HAE between January 1996 and December 2019.

METHODS

Data were retrieved from medical records of Paediatric Immunodeficiency Clinic, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

RESULTS

Median age at onset of symptoms was 6.25 years (range 1-25 years), and median age at diagnosis was 12 years (range 2-43 years). Serum complement C4 level was decreased in all patients. All patients had low C1-esterase inhibitor (C1-INH) quantitative level (type 1 HAE). SERPING1 gene sequencing could be carried out in 20 families. Of these, 11 were identified to have a pathogenic disease-causing variant in the SERPING1 gene. While 2 of these families had a previously reported mutation, remaining 9 families had novel pathogenic variants in SERPING1 gene. Because of non-availability of C1-INH therapy in India, all patients were given long-term prophylaxis (attenuated androgens or tranexamic acid (TA) or a combination of the 2). Life-threatening episodes of laryngeal edema were managed with fresh-frozen plasma (FPP) infusions. We recorded one disease-related mortality in our cohort. This happened in spite of long-term prophylaxis with stanozolol and TA.

CONCLUSIONS

We report largest single-center cohort of patients with HAE from India. Attenuated androgens, fibrinolytic agents, and FPP may be used for management of HAE in resource-limited settings.

Hereditary angioedema: On-demand treatment of angioedema attacks

The availability of effective acute treatment for angioedema has been fundamental in reducing the burden of illness for patients with hereditary angioedema (HAE). In building on the foundation of scientific advances that elucidate the pathomechanism(s) of attacks related to vascular permeability, novel targeted on-demand treatments have been developed and approved. These therapies have provided the means to arrest episodes of swelling, which, in the past, had the potential to inexorably lead to morbidity, and even mortality, for patients with HAE. Access to these medications, along with an emphasis on early administration and guidance that all attacks are candidates for treatment, has shifted the management paradigm for HAE. Although unmet needs remain, these acute therapies, coupled with advances in prophylactic treatment, have furthered the goal for all patients with HAE to live a normal life.

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.

Novel Use of Fresh Frozen Plasma in Treating Hereditary Angioedema: A Success Story From Pakistan

Hereditary angioedema (HAE) due to a C1-esterase inhibitor(C1-INH) deficiency is a rare and potentially life-threatening disorder. It is characterized by an episodic and self-limiting increase in vascular permeability. The condition manifests itself as recurrent attacks of swelling in any part of the body. The angioedema can cause the involvement of the respiratory tract, skin, and gastrointestinal tract. Laryngeal involvement can make the condition life-threatening. It does not respond well to conventional angioedema therapy of steroids, adrenaline, and antihistamines. The targeted therapy for HAE consists of plasma-derived or recombinant C1-INH, ecallantide, and icatibant or bradykinin receptor antagonist. In the absence of these therapies, it becomes difficult to manage this condition effectively. We present a case of hereditary angioedema, who presented with life-threatening laryngeal edema, causing asphyxia, leading to cardiac arrest. Due to a lack of availability of C1-INH concentrate, he was given fresh frozen plasma (FFP). His condition gradually improved, and he was successfully extubated after three days. This is the first time we are reporting a case from Pakistan in which the patient was successfully treated with FFP for an acute attack of hereditary angioedema.