High Estrogen States in Hereditary Angioedema: a Spectrum

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.

Concomitant medication in patients with bradykinin-mediated angioedema - there's more than ACE inhibitors

Bradykinin-mediated angioedema is a rare, non-allergic, potentially life-threatening disease. ACE inhibitor-induced angioedema and hereditary angioedema (HAE) are the two most common presentations. Therapeutic options, pathophysiology and diagnosis continue to be investigated, with considerable progress in HAE over the last few decades. For all patients with bradykinin-mediated angioedema, there are several medications that should be avoided or administered with caution. Some of the triggering medications are well known, while others are suspected or of unknown significance. A common denominator is that there is no approved therapy for bradykinin-mediated angioedema as a drug side effect. Some medications, such as tissue plasminogen activator, have a higher incidence of angioedema with potential airway compromise than ACE inhibitors, although this fact is widely underappreciated. In this review, we aim to summarize what is currently known and recommended about concomitant medication in HAE patients and the interaction of other bradykinin-influencing drugs.

Hypersensitivity reactions amongst Hungarian Patients with Hereditary Angioedema due to C1-Inhibitor Deficiency

Background

In hereditary angioedema (HAE) due to C1-inhibitor deficiency (C1-INH-HAE), bradykinin-mediated submucosal and/or subcutaneous angioedema dominates the clinical picture. The deficiency of C1-inhibitor can lead to the over-activation of the complement system. Complement plays an important role in all types of hypersensitivity reactions. On the other hand, during the degranulation of mast cells, heparin is also released amongst other substances. Heparin can activate the plasma kinin-kallikrein system, leading to bradykinin generation. These observations suggest a possible connection between C1-INH-HAE and mast cell-mediated hypersensitivity reactions.

Objective

To assess the occurrence of hypersensitivity reactions in the Hungarian C1-INH-HAE population.

Methods

Patients filled out a questionnaire of 112 questions, either online or on paper. The questions were about hypersensitivity and C1-INH-HAE symptoms, the relation between these 2, general health, and demographic data. The study protocol was approved by the institutional review board of Semmelweis University, Budapest, and informed consent was obtained from the participants.

Results

One hundred and six patients (64 female, 42 male, median age 46 years) responded, with 63.2% having hypersensitivity. Hypersensitivity was provoked by pollen in 25.5% of patients, by contact sensitivity in 22.6%, by food in 21.7%, by insect sting in 19.8%, by pet in 15.1%, by drug in 14.2%, by dust mite in 5.7%, and by mold in 1.9%. In 11 patients, hypersensitivity symptoms appeared after the diagnosis of C1-INH-HAE. Six hypersensitive patients experienced improvement in their symptoms; 42 remained the same, but none experienced worsening after the diagnosis of C1-INH-HAE. In 7.8% of the hypersensitive patients, a C1-INH-HAE attack worsened the hypersensitivity symptoms, while 15.7% of the hypersensitive patients experienced a C1-INH-HAE attack provoked by contact with the provoking factor.

Conclusion

While 63.2% of our C1-INH-HAE patients have reported hypersensitivity symptoms, Eurostat's latest data puts the prevalence of self-reported allergies in Hungary at 19.3%. Since in our experience most Hungarian patients report hypersensitivity reactions as allergies, this may support a possible connection between the 2 diseases, but further molecular studies are needed.

Medikamente als Auslöser Bradykinin-vermittelter Angioödeme - mehr als ACE-Hemmer

Bradykinin‐vermittelte Angioödeme sind seltene, nichtallergische und potenziell lebensbedrohliche Krankheiten. Die beiden bekanntesten Formen sind das ACE‐Hemmer‐induzierte Angioödem und das hereditäre Angioödem (HAE). Die therapeutischen Möglichkeiten, die Pathophysiologie und die Diagnostik werden weiter erforscht, wobei beim HAE in den letzten Jahrzehnten erhebliche Fortschritte erzielt wurden. Für alle Patienten mit Bradykinin‐vermittelten Angioödemen gibt es Medikamente, die vermieden oder mit Vorsicht verabreicht werden sollten. Einige dieser auslösenden Medikamente sind gut bekannt, bei anderen wird ein Zusammenhang vermutet oder ihre Bedeutung ist unbekannt. Ein gemeinsamer Nenner ist, dass es keine zugelassene Therapie für das Bradykinin‐vermittelte Angioödem als Arzneimittelnebenwirkung gibt. Bei einigen Medikamenten, wie dem gewebespezifischen Plasminogenaktivator, ist die Inzidenz von Angioödemen mit möglicher Beeinträchtigung der Atemwege höher als bei ACE‐Hemmern, wobei diese Tatsache weitgehend unterschätzt wird. In dieser Übersichtsarbeit fassen wir zusammen, was derzeit über die Begleitmedikation bei HAE‐Patienten und die Interaktion mit anderen Bradykinin‐beeinflussenden Medikamenten bekannt ist und empfohlen wird.

A Case Report about the Management of Hereditary Angioedema with Normal Complement Levels during Pregnancy

N/a. 

The impact of puberty on the onset, frequency, location, and severity of attacks in hereditary angioedema due to C1-inhibitor deficiency: A survey from the Italian Network for Hereditary and Acquired Angioedema (ITACA)

INTRODUCTION

Hereditary angioedema due to C1-inhibitor deficiency is influenced by hormonal factors, with a more severe course of disease in women. Our study aims to deepen the impact of puberty on onset, frequency, location and severity of attacks.

METHODS

Retrospective data were collected through a semi-structured questionnaire and shared by 10 Italian reference centers of the Italian Network for Hereditary and Acquired Angioedema (ITACA).

RESULTS

The proportion of symptomatic patients increased significantly after puberty (98.2% vs 83.9%, p=0.002 in males; 96.3% vs 68,4%, p<0.001 in females); the monthly mean of acute attacks was significantly higher after puberty, and this occurred both in females (median (IQR) = 0.41(2) in the three years before puberty vs 2(2.17) in the three years after, p<0.001) and in males (1(1.92) vs 1.25(1.56) respectively, p<0.001). The increase was greater in females. No significant differences were detected in attack location before and after puberty.

DISCUSSION

Overall, our study confirms previous reports on a more severe phenotype in the female gender. Puberty predisposes to increased numbers of angioedema attacks, in particular in female patients.

Hereditary Angioedema with Normal C1 Esterase Inhibitor Refractory to Long-Term Prophylaxis: A Case Report

Hereditary angioedema (HAE) was classically thought to be related to a deficiency in the C1 esterase inhibitor (C1-INH). However, HAE with a normal C1 esterase inhibitor (HAE nC1-INH) is a rare disease that has been recently characterized. In this case, we describe a woman with a 21-year history of angioedema who, in the last two years, has experienced severe exacerbations that led to the formal diagnosis of HAE nC1-INH. The patient has been treated with current HAE long-term prophylaxis (LTP) and on-demand therapies but is still experiencing severe, frequent attacks. Our case describes the timeline of this patient's presentation and provides valuable insight into the presentation and management of HAE nC1-INH.

A catalog of the genetic causes of hereditary angioedema in the Canary Islands (Spain)

Hereditary angioedema (HAE) is a rare disease where known causes involve C1 inhibitor dysfunction or dysregulation of the kinin cascade. The updated HAE management guidelines recommend performing genetic tests to reach a precise diagnosis. Unfortunately, genetic tests are still uncommon in the diagnosis routine. Here, we characterized for the first time the genetic causes of HAE in affected families from the Canary Islands (Spain). Whole-exome sequencing data was obtained from 41 affected patients and unaffected relatives from 29 unrelated families identified in the archipelago. The Hereditary Angioedema Database Annotation (HADA) tool was used for pathogenicity classification and causal variant prioritization among the genes known to cause HAE. Manual reclassification of prioritized variants was used in those families lacking known causal variants. We detected a total of eight different variants causing HAE in this patient series, affecting essentially SERPING1 and F12 genes, one of them being a novel SERPING1 variant (c.686-12A>G) with a predicted splicing effect which was reclassified as likely pathogenic in one family. Altogether, the diagnostic yield by assessing previously reported causal genes and considering variant reclassifications according to the American College of Medical Genetics guidelines reached 66.7% (95% Confidence Interval [CI]: 30.1-91.0) in families with more than one affected member and 10.0% (95% CI: 1.8-33.1) among cases without family information for the disease. Despite the genetic causes of many patients remain to be identified, our results reinforce the need of genetic tests as first-tier diagnostic tool in this disease, as recommended by the international WAO/EAACI guidelines for the management of HAE.