Hereditary angioedema: Assessing the hypothesis for underlying autonomic dysfunction

Neurologic and Psychiatric Manifestations of Bradykinin-Mediated Angioedema: Old and New Challenges

Neurologic manifestations have been occasionally described in patients with bradykinin-mediated angioedema. The existing literature is currently limited to case series and case reports mainly described in the hereditary forms (HAE) concerning central nervous system (CNS) involvement. On the contrary, very little is known about peripheral and autonomic nervous system manifestations. CNS involvement in HAE may present with symptoms including severe headaches, visual disturbance, seizures, and various focal and generalized deficits. In addition, a stroke-like clinical picture may present in HAE patients. In turn, some drugs used in patients with cardiovascular and neurologic disorders, such as recombinant tissue plasminogen activator (r-tPA) and angiotensin-converting enzyme inhibitors (ACEI), may produce medication-induced angioedema, resulting in a diagnostic challenge. Finally, most patients with HAE have higher levels of psychological distress, anxiety, and depression. With this review, we aimed to provide an organized and detailed analysis of the existing literature on neurologic and psychiatric manifestations of HAE to shed light on these potentially invalidating symptoms and lay the foundation for further personalized diagnostic pathways for patients affected by this protean disease.

Immunogenicity and Safety of Anti-SARS-CoV-2 mRNA Vaccines in a Cohort of Patients with Hereditary Angioedema

Many factors may trigger hereditary angioedema (HAE) attacks. This study aims to gain insights into the benefits and potential risks of COVID-19 vaccination in HAE patients, focusing particularly on the possibility of triggering attacks. We enrolled 31 patients with HAE undergoing two doses of the SARS-CoV-2 mRNA Comirnaty-BioNTech/Pfizer vaccine. To evaluate the possible influence of the vaccine on disease control and attack frequency, we administered the angioedema control test (AECT) 4-week version before (T0), 21 days after the first dose (T1), and between 21 and 28 days after the second dose (T2). Despite 5 patients (16.1%) experiencing attacks within 72 h of the first dose administration, no significant variation in attack frequency was observed before and after vaccination [F(2,60) = 0.123; p = 0.799]. In addition, patients reported higher AECT scores at T1 and T2 compared to T0 [F(2,44) = 6.541; p < 0.05; post hoc p < 0.05)], indicating that the disease was rather more controlled after vaccinations than in the previous period. All patients showed a positive serological response to the vaccine without significant differences from healthy controls (U = 162; p = 0.062). These observations suggest that the vaccine administration is safe and effective in HAE patients.

Molecular Dambusters: What Is Behind Hyperpermeability in Bradykinin-Mediated Angioedema?

In the last few decades, a substantial body of evidence underlined the pivotal role of bradykinin in certain types of angioedema. The formation and breakdown of bradykinin has been studied thoroughly; however, numerous questions remained open regarding the triggering, course, and termination of angioedema attacks. Recently, it became clear that vascular endothelial cells have an integrative role in the regulation of vessel permeability. Apart from bradykinin, a great number of factors of different origin, structure, and mechanism of action are capable of modifying the integrity of vascular endothelium, and thus, may participate in the regulation of angioedema formation. Our aim in this review is to describe the most important permeability factors and the molecular mechanisms how they act on endothelial cells. Based on endothelial cell function, we also attempt to explain some of the challenging findings regarding bradykinin-mediated angioedema, where the function of bradykinin itself cannot account for the pathophysiology. By deciphering the complex scenario of vascular permeability regulation and edema formation, we may gain better scientific tools to be able to predict and treat not only bradykinin-mediated but other types of angioedema as well.

Analysis of Heart-Rate Variability during Angioedema Attacks in Patients with Hereditary C1-Inhibitor Deficiency

C1-inhibitor hereditary angioedema (C1-INH-HAE) is a rare disease characterized by self-limiting edema associated with localized vasodilation due to increased levels of circulating bradykinin. C1-INH-HAE directly influences patients' everyday lives, as attacks are unpredictable in frequency, severity, and the involved anatomical site. The autonomic nervous system could be involved in remission. The cardiac autonomic profile has not yet been evaluated during the attack or prodromal phases. In this study, a multiday continuous electrocardiogram was obtained in four C1-INH-HAE patients until attack occurrence. Power spectral heart rate variability (HRV) indices were computed over the 4 h preceding the attack and during the first 4 h of the attack in three patients. Increased vagal modulation of the sinus node was detected in the prodromal phase. This finding may reflect localized vasodilation mediated by the release of bradykinin. HRV analysis may furnish early markers of an impending angioedema attack, thereby helping to identify patients at higher risk of attack recurrence. In this perspective, it could assist in the timing, titration, and optimization of prophylactic therapy, and thus improve patients' quality of life.

The central role of endothelium in hereditary angioedema due to C1 inhibitor deficiency

An impairment of the endothelial barrier function underlies a wide spectrum of pathological conditions. Hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE) can be considered the "pathophysiological and clinical paradigm" of Paroxysmal Permeability Diseases (PPDs), conditions characterized by recurrent transient primitively functional alteration of the endothelial sieving properties, not due to inflammatory-ischemic-degenerative injury and completely reversible after the acute flare. It is a rare yet probably still underdiagnosed disease which presents with localized, non-pitting swelling of the skin and submucosal tissues of the upper respiratory and gastrointestinal tracts, without significant wheals or pruritus. The present review addresses the pathophysiology of C1-INH-HAE with a focus on the crucial role of the endothelium during contact and kallikrein/kinin system (CAS and KKS) activation, currently available and emerging biomarkers, methods applied to get new insights into the mechanisms underlying the disease (2D, 3D and in vivo systems), new promising investigation techniques (autonomic nervous system analysis, capillaroscopy, flow-mediated dilation method, non-invasive finger plethysmography). Hints are given to the binding of C1-INH to endothelial cells. Finally, crucial issues as the local vs systemic nature of CAS/KKS activation, the episodic nature of attacks vs constant C1-INH deficiency, pros and cons as well as future perspectives of available methodologies are briefly discussed.

Myocardial edema in paroxysmal permeability disorders: The paradigm of Clarkson's disease

PURPOSE

Paroxysmal Permeability Disorders (PPDs) comprise a variety of diseases characterized by recurrent and transitory increase of endothelial permeability. Idiopathic Systemic Capillary Leak Syndrome (ISCLS) is a rare PPD that leads to an abrupt massive shift of fluids and proteins from the intravascular to the interstitial compartment. In some cases, tissue edema may involve the myocardium, but its role in the development of shock has not been elucidated so far.

MATERIALS AND METHODS

Assessment of cardiac involvement during ten life-threatening ISCLS episodes admitted to ICU.

RESULTS

Transthoracic echocardiographic examination was performed in eight episodes, whereas a poor acoustic window prevented cardiac ultrasound assessment in two episodes. Myocardial edema was detected by echocardiography in eight episodes and marked pericardial effusion in one-episode. Cardiac magnetic resonance showed diffuse myocardial edema in another episode. In one case, myocardial edema caused fulminant left ventricular dysfunction, which required extracorporeal life support. The mean septum thickness was higher during the shock phase compared to the recovery phase [15.5 mm (13.1-21 mm) vs. 9.9 mm (9-11.3 mm), p = .0003]. Myocardial edema resolved within 72 h.

CONCLUSIONS

During early phases of ISCLS, myocardial edema commonly occurs and can induce transient myocardial dysfunction, potentially contributing to the pathogenesis of shock.

Emotional processes and stress in children affected by hereditary angioedema with C1-inhibitor deficiency: a multicenter, prospective study

Background

Hereditary angioedema with C1-inhibitor deficiency (C1-INH-HAE) is characterized by recurrent edema of unpredictable frequency and severity. Stress, anxiety, and low mood are among the triggering factors most frequently reported. Impaired regulation and processing of emotions, also known as alexithymia, may influence outcomes. The aim of this study was to confirm the presence of alexithymia and stress in children with C1-INH-HAE, to determine whether they are also present in children affected by other chronic diseases, and to investigate their relationship with C1-INH-HAE severity. Data from children with C1-INH-HAE (n = 28) from four reference centers in Italy were compared with data from children with type 1 diabetes (T1D; n = 23) and rheumatoid arthritis (RA; n = 25). Alexithymia was assessed using the Alexithymia Questionnaire for Children scale; perceived stress was assessed using the Coddington Life Event Scale for Children (CLES-C).

Results

Mean age (standard deviation [SD]) in the C1-INH-HAE, T1D, and RA groups was 11.8 (3.3), 11.7 (2.9), and 11.1 (2.6) years, respectively. Mean C1-INH-HAE severity score was 5.9 (2.1), indicating moderate disease. Alexithymia scores were similar among disease groups and suggestive of difficulties in identifying and describing emotions; CLES-C scores tended to be worse in C1-INH-HAE children. C1-INH-HAE severity was found to correlate significantly and positively with alexithymia (p = 0.046), but not with perceived stress. Alexithymia correlated positively with perceived stress.

Conclusions

Alexithymia is common in children with chronic diseases. In C1-INH-HAE, it may result in increased perceived stress and act as a trigger of edema attacks. Comprehensive management of C1-INH-HAE children should consider psychological factors.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0871-x) contains supplementary material, which is available to authorized users.

Impaired Endothelial Function in Hereditary Angioedema During the Symptom-Free Period

Introduction: The presence of coronary endothelial dysfunction was previously shown in Hereditary Angioedema (HAE) patients. The aim of our study was to evaluate the effect of HAE on systemic endothelial function and whether there was a relationship among endothelial function, asymmetric dimethylarginine (ADMA) -which is a strong inhibitor of nitric oxide synthesis-, and disease severity scores. Methods: Twenty-four HAE patients (18 females, aged 47.9 ± 2 years) without factors known to interfere with endothelial function were studied and compared with 24 healthy peers age- and gender-matched. Endothelial function was assessed by means of non-invasive finger plethysmography (reactive hyperaemia index: RHI) and ADMA levels by high-performance liquid chromatography. HAE severity scores have been calculated according to published literature. Results: In HAE patients RHI was lower (2.03 ± 0.46 vs. 2.82 ± 0.34, p < 0.0001) and ADMA higher (0.636 ± 7 vs. 585 ± 5 micromol/L, p < 0.01) than in controls. A statistically significant inverse correlation was revealed between RHI and patients' ADMA levels (r = -0.516, p = 0.009) as well as between RHI and patients' chronological age (r = -0.49, p = 0.015). A statistically significant correlation between RHI and ADMA was confirmed even when excluding the possible influence of cholesterol (r = -0.408, p = 0.048). No other significant correlations were found with the examined laboratory and clinical parameters (chronological age, age at disease onset, disease duration, severity scores, and gender). Conclusion: The dysfunction previously shown in HAE patients at the coronary arteries seems to involve the peripheral vessels as well, without a correlation with disease severity.