The Effects of High-Fat Diet and Flaxseed Oil-Enriched Diet on the Lung Parenchyma of Obese Mice.

Omega-3 (ω3) fatty acids are widely investigated for their anti-inflammatory potential, however, there is little evidence regarding their action in the lung parenchyma in the context of obesity. The objective is to investigate the effects of flaxseed oil (FS), rich in α-linolenic (C18:3 - ω3), on the lungs of obese mice. Mice were fed a high-fat diet (HF) for 8 weeks to induce obesity. Subsequently, a part of these animals received HF containing FS oil for another 8 weeks. The HF consumption induced weight gain and hyperglycemia. The lung parenchyma shows a complete fatty acids profile, compared to the control group (CT). In the lung parenchyma, FS increases the ω3 content and, notwithstanding a reduction in the interleukins (IL) IL1ß and IL18 contents compared to HF. However, FS promoted increased alveolar spaces, followed by MCP1 (Monocytes Chemoattractant Protein-1) positive cell infiltration and a dramatic reduction in the anti-inflammatory cytokine, IL10. Despite reducing the pulmonary inflammatory response, the consumption of a food source of ω3 was associated with alterations in the lipid profile and histoarchitecture of the lung parenchyma, which can lead to the development of pulmonary complications. This study brings an alert against the indiscriminate use of ω3 supplements, warranting caution.

Angiopoietin2 is associated with coagulation activation and tissue factor expression in extracellular vesicles in COVID-19.

Coagulation activation in immunothrombosis involves various pathways distinct from classical hemostasis, offering potential therapeutic targets to control inflammation-induced hypercoagulability while potentially sparing hemostasis. The Angiopoietin/Tie2 pathway, previously linked to embryonic angiogenesis and sepsis-related endothelial barrier regulation, was recently associated with coagulation activation in sepsis and COVID-19. This study explores the connection between key mediators of the Angiopoietin/Tie2 pathway and coagulation activation. The study included COVID-19 patients with hypoxia and healthy controls. Blood samples were processed to obtain platelet-free plasma, and frozen until analysis. Extracellular vesicles (EVs) in plasma were characterized and quantified using flow cytometry, and their tissue factor (TF) procoagulant activity was measured using a kinetic chromogenic method. Several markers of hemostasis were assessed. Levels of ANGPT1, ANGPT2, and soluble Tie2 correlated with markers of coagulation and platelet activation. EVs from platelets and endothelial cells were increased in COVID-19 patients, and a significant increase in TF+ EVs derived from endothelial cells was observed. In addition, ANGPT2 levels were associated with TF expression and activity in EVs. In conclusion, we provide further evidence for the involvement of the Angiopoietin/Tie2 pathway in the coagulopathy of COVID-19 mediated in part by release of EVs as a potential source of TF activity.

Indução oral rápida de tolerância a alopurinol: um relato de caso / Rapid induction of oral tolerance to allopurinol: a case report

O alopurinol, de uso contínuo oral, é o tratamento de escolha para os distúrbios hereditários do glicogênio. Apesar de não ser comum, a reação de hipersensibilidade ao alopurinol se torna um problema quando esta é a única medicação disponível para o controle da doença de base. Nestes casos, a dessensibilização é uma alternativa viável. No presente relato, descrevemos o caso de um paciente com diagnóstico de doença de depósito de glicogênio tipo I, com exantema pruriginoso generalizado ao alopurinol, tratado com um protocolo de dessensibilização oral acelerado. Este tratamento permitiu o uso contínuo deste medicamento sem novas reações em longo prazo.

Continuous oral allopurinol use is the first-line treatment for hereditary glycogen disorders. While hypersensitivity reactions to allopurinol are uncommon, they can pose challenges when this medication is the only available option for the long-term treatment of the underlying disorder. In such cases, desensitization emerges as a viable alternative. We report the case of a patient with glycogen storage disease type I who developed a generalized pruritic rash due to allopurinol. Drug intolerance was successfully managed using a rapid oral desensitization protocol, which allowed an uneventful long-term use of allopurinol.

Hipogamaglobulinemia e rituximabe: relato de casos / Hypogammaglobulinemia and rituximab: case reports

Secondary immunodeficiency can result from neoplasms, infections, or immunosuppressive therapy. Rituximab (RTX) is an anti-CD20 antibody that depletes B lymphocytes and can induce symptomatic hypogammaglobulinemia. We report 3 cases of symptomatic hypogammaglobulinemia associated with the use of RTX. In patient 1 with rheumatoid arthritis, RTX induced low levels of immunoglobulins and recurrent airway infections. RTX discontinuation led to a normalization of the humoral immune response. Patients 2 and 3, treated with RTX for non-Hodgkin lymphoma and systemic lupus erythematosus, respectively, developed persistent secondary hypogammaglobulinemia requiring immunoglobulin replacement therapy for years. After RTX discontinuation, patients may experience rapid recovery of humoral function or remain with low serum immunoglobulin levels for extended periods. With the increasing use of therapies targeting components of the immune system, a high degree of clinical suspicion for the development of secondary immunodeficiency may minimize the morbidity and mortality associated with these therapies.

As imunodeficiências secundárias podem ser uma consequência de neoplasias, infecções ou tratamentos imunossupressores. O rituximabe (RTX) é um anticorpo anti-CD20 que depleta os linfócitos B e pode induzir uma hipogamaglobulinemia sintomática. Aqui, relatamos três casos de hipogamaglobulinemia sintomática associada ao uso de RTX. Na primeira paciente com artrite reumatoide, o RTX induziu a baixos níveis de imunoglobulinas associadas a infecções de vias aéreas de repetição. Após a suspensão do RTX, houve normalização da resposta imune humoral. Os outros dois casos, com o uso de RTX para tratamento de linfoma não-Hodgkin e lúpus eritematoso sistêmico, respectivamente, as pacientes evoluíram com hipogamaglobulinemia secundária persistente, com necessidade de reposição de imunoglobulina por vários anos. Pacientes tratados com RTX podem apresentar, após a sua suspensão, uma recuperação rápida da função humoral ou permanecerem com baixos níveis séricos de imunoglobulinas por longos períodos. Com o crescente uso dos tratamentos direcionados para componentes do sistema imunológico, um alto grau de suspeição clínica para o aparecimento de imunodeficiências secundárias pode minimizar a morbimortalidade associada a estes tratamentos.

SARS-CoV-2 uses CD4 to infect T helper lymphocytes.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here, we show that SARS-CoV-2 infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS- CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.

Are pediatricians familiar with hereditary angioedema?

Background: Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of subcutaneous or mucosal edema caused by excess bradykinin. The aim of the present study was to assess the knowledge of pediatricians about hereditary angioedema. Methods: An online survey with 12 HAE-related and 14 demographics-related questions was e-mailed to all pediatricians who were members of the Brazilian Society of Pediatrics (n = 17 145) once a week during the months of June and July 2021. The electronic questionnaire assessed clinical manifestations, diagnosis, and treatment of hereditary angioedema in children and adolescents. Results: Four hundred and fifty-five pediatricians responded to the questionnaire (2.6%), of whom 55 (12.1%) were board certified in Allergy and Immunology (A/I), while 400 (87.9%) were not (N-A/I). Three hundred and sixty-eight (80.9%) were female, 289 (55.7%) were under 50 years of age, 286 (62.9%) graduated from Medical School more than 10 years previously, 83 (18.2%) held an MSc/PhD degree, and 253 (55.6%) were living in the Southeast Region of Brazil. The median number of correct answers to the questions related to HAE among A/I was 7 out of 12 (58.3%), with median ranging from 4.5 to 8 correct answers, while for N-A/I it was 3 (25%), with median ranging from 2.5 to 4 correct answers (p < 0.001). Conclusion: Knowledge about HAE among Brazilian pediatricians, whether board certified in Allergy and Immunology or not, was unsatisfactory. HAE is a rare disease, largely unknown among physicians; therefore, increasing awareness may lead to improvement in diagnosis and treatment.

Podoplanin and CLEC-2 levels in patients with COVID-19.

Introduction: Podoplanin (PDPN gene) and CLEC-2 are involved in inflammatory hemostasis and have also been related with the pathogenesis of thrombosis. Emerging evidence also suggest that podoplanin can exert protective effects in sepsis and in acute lung injury. In lungs, podoplanin is co-expressed with ACE2, which is the main entry receptor for SARS-CoV-2. Aim: To explore the role of podoplanin and CLEC-2 in COVID-19. Methods: Circulating levels of podoplanin and CLEC-2 were measured in 30 consecutive COVID-19 patients admitted due to hypoxia, and in 30 age- and sex-matched healthy individuals. Podoplanin expression in lungs from patients who died of COVID-19 was obtained from two independent public databases of single-cell RNAseq from which data from control lungs were also available. Results: Circulating podoplanin levels were lower in COVID-19, while no difference was observed in CLEC-2 levels. Podoplanin levels were significantly inversely correlated with markers of coagulation, fibrinolysis and innate immunity. scRNAseq data confirmed that PDPN is co-expressed with ACE2 in pneumocytes, and showed that PDPN expression is lower in this cell compartment in lungs from patients with COVID-19. Conclusion: Circulating levels of podoplanin are lower in COVID-19, and the magnitude of this reduction is correlated with hemostasis activation. We also demonstrate the downregulation of PDPN at the transcription level in pneumocytes. Together, our exploratory study questions whether an acquired podoplanin deficiency could be involved in the pathogenesis of acute lung injury in COVID-19, and warrant additional studies to confirm and refine these findings.

Association of Ang/Tie2 pathway mediators with endothelial barrier integrity and disease severity in COVID-19.

Endothelial barrier (EB) disruption contributes to acute lung injury in COVID-19, and levels of both VEGF-A and Ang-2, which are mediators of EB integrity, have been associated with COVID-19 severity. Here we explored the participation of additional mediators of barrier integrity in this process, as well as the potential of serum from COVID-19 patients to induce EB disruption in cell monolayers. In a cohort from a clinical trial consisting of thirty patients with COVID-19 that required hospital admission due to hypoxia we demonstrate that i) levels of soluble Tie2 were increase, and of soluble VE-cadherin were decreased when compared to healthy individuals; ii) sera from these patients induce barrier disruption in monolayers of endothelial cells; and iii) that the magnitude of this effect is proportional to disease severity and to circulating levels of VEGF-A and Ang-2. Our study confirms and extends previous findings on the pathogenesis of acute lung injury in COVID-19, reinforcing the concept that EB is a relevant component of this disease. Our results pave the way for future studies that can refine our understanding of the pathogenesis of acute lung injury in viral respiratory disorders, and contribute to the identification of new biomarkers and therapeutic targets for these conditions.

Association of heme-oxygenase 1, hemopexin, and heme levels with markers of disease severity in COVID-19.

Heme-oxygenase 1 (HO-1) is an enzyme with well-known anti-inflammatory and antioxidant properties, whose levels have been previously associated with disease severity in the context of sterile and infectious diseases. Moreover, the heme/HO-1 pathway has been associated with prothrombotic changes in other diseases. Accordingly, the potential of modulating HO-1 levels for the treatment of COVID-19 was extensively speculated during the COVID-19 pandemic, but very few actual data were generated. The aim of our study was to explore the association of HO-1, heme, and hemopexin (HPX) levels with COVID-19 severity and with markers of inflammation and coagulation activation. The study was conducted in 30 consecutive patients with COVID-19 admitted due to hypoxemia, and 30 healthy volunteers matched by sex, age, and geographic region. HO-1 and HPX levels were measured by enzyme immunoassay (ELISA) and heme levels were measured by a colorimetric method. A comprehensive panel of coagulation and fibrinolysis activation was also used. Patients with COVID-19 presented increased levels of HO-1 when compared to controls (5741 ± 2696 vs 1953 ± 612 pg/mL, respectively, P < 0.0001), as well as a trend toward increased levels of HPX (3.724 ± 0.880 vs 3.254 ± 1.022 mg/mL, respectively; P = 0.06). In addition, HO-1 and HPX levels reduced from admission to day + 4. HO-1 levels were associated with duration of intensive care unit stay and with several markers of coagulation activation. In conclusion, modulation of HO-1 could be associated with the prothrombotic state observed in COVID-19, and HO-1 could also represent a relevant biomarker for COVID-19. New independent studies are warranted to explore and expand these findings.

Plasma Angiotensin II Is Increased in Critical Coronavirus Disease 2019.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) employs angiotensin-converting enzyme 2 (ACE2) as its receptor for cell entrance, and studies have suggested that upon viral binding, ACE2 catalytic activity could be inhibited; therefore, impacting the regulation of the renin-angiotensin-aldosterone system (RAAS). To date, only few studies have evaluated the impact of SARS-CoV-2 infection on the blood levels of the components of the RAAS. The objective of this study was to determine the blood levels of ACE, ACE2, angiotensin-II, angiotensin (1-7), and angiotensin (1-9) at hospital admission and discharge in a group of patients presenting with severe or critical evolution of coronavirus disease 2019 (COVID-19). We showed that ACE, ACE2, angiotensin (1-7), and angiotensin (1-9) were similar in patients with critical and severe COVID-19. However, at admission, angiotensin-II levels were significantly higher in patients presenting as critical, compared to patients presenting with severe COVID-19. We conclude that blood levels of angiotensin-II are increased in hospitalized patients with COVID-19 presenting the critical outcome of the disease. We propose that early measurement of Ang-II could be a useful biomarker for identifying patients at higher risk for extremely severe progression of the disease.

Increased Serum Mir-150-3p Expression Is Associated with Radiological Lung Injury Improvement in Patients with COVID-19.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus, responsible for an atypical pneumonia that can progress to acute lung injury. MicroRNAs are small non-coding RNAs that control specific genes and pathways. This study evaluated the association between circulating miRNAs and lung injury associated with COVID-19. Methods: We evaluated lung injury by computed tomography at hospital admission and discharge and the serum expression of 754 miRNAs using the TaqMan OpenArray after hospital discharge in 27 patients with COVID-19. In addition, miR-150-3p was validated by qRT-PCR on serum samples collected at admission and after hospital discharge. Results: OpenArray analysis revealed that seven miRNAs were differentially expressed between groups of patients without radiological lung improvement compared to those with lung improvement at hospital discharge, with three miRNAs being upregulated (miR-548c-3p, miR-212-3p, and miR-548a-3p) and four downregulated (miR-191-5p, miR-151a-3p, miR-92a-3p, and miR-150-3p). Bioinformatics analysis revealed that five of these miRNAs had binding sites in the SARS-CoV-2 genome. Validation of miR-150-3p by qRT-PCR confirmed the OpenArray results. Conclusions: The present study shows the potential association between the serum expression of seven miRNAs and lung injury in patients with COVID-19. Furthermore, increased expression of miR-150 was associated with pulmonary improvement at hospital discharge.

Hereditary angioedema in children and adolescents.

Hereditary angioedema is a genetic disease with autosomal dominant inheritance and, in most cases, caused by C1 inhibitor deficiency. Patients present with recurrent edema affecting sub-cutaneous and mucus membranes with variable onset and severity. More than 50% of patients may become symptomatic before 10 years of age. Family history can help with the diagnosis; however, approximately 25% of the cases are de novo mutations. Biochemical diagnosis should be delayed until after 1 year of age. Children were often excluded from advances in therapy for hereditary angioedema since most of the new medicines were tested in adults and thus excluded by the Food and Drug Administration (FDA) and other agencies for approval to be used in children. Treatment of attacks is available for the pediatric patient; however, barriers still exist for the use of long-term prophylaxis in young children. © 2022 Codon Publications. Published by Codon Publications.

Diretrizes brasileiras do angioedema hereditário 2022 ­ Parte 1: definição, classificação e diagnóstico / 2022 Brazilian guidelines for hereditary angioedema ­ Part 1: definition, classification, and diagnosis

O angioedema hereditário é uma doença autossômica dominante caracterizada por crises recorrentes de edema que acometem o tecido subcutâneo e o submucoso, com envolvimento de diversos órgãos. Os principais locais afetados são face, membros superiores e inferiores, as alças intestinais e as vias respiratórias superiores. Em decorrência da falta de conhecimento dessa condição por profissionais de saúde, ocorre atraso importante no seu diagnóstico, comprometendo a qualidade de vida dos indivíduos afetados. Além disso, o retardo no diagnóstico pode resultar em aumento da mortalidade por asfixia devido ao edema de laringe. A natureza errática das crises com variação do quadro clínico e gravidade dos sintomas entre diferentes pacientes, e no mesmo paciente ao longo da vida, se constitui em desafio no cuidado dos doentes que têm angioedema hereditário. O principal tipo de angioedema hereditário é resultante de mais de 700 variantes patogênicas do gene SERPING1 com deficiência funcional ou quantitativa da proteína inibidor de C1, porém nos últimos anos outras mutações foram descritas em seis outros genes. Ocorreram avanços importantes na fisiopatologia da doença e novas drogas para o tratamento do angioedema hereditário foram desenvolvidas. Nesse contexto, o Grupo de Estudos Brasileiro em Angioedema Hereditário (GEBRAEH) em conjunto com a Associação Brasileira de Alergia e Imunologia (ASBAI) atualizou as diretrizes brasileiras do angioedema hereditário. O maior conhecimento dos diversos aspectos resultou na divisão das diretrizes em duas partes, sendo nessa primeira parte abordados a definição, a classificação e o diagnóstico.

Hereditary angioedema is an autosomal dominant disease characterized by recurrent attacks of edema that affect the subcutaneous tissue and the submucosa, involving several organs. The main affected sites are the face, upper and lower limbs, gastrointestinal tract, and upper airways. Because health professionals lack knowledge about this condition, there is a significant delay in diagnosis, compromising the quality of life of affected individuals. Furthermore, delayed diagnosis may result in increased mortality from asphyxia due to laryngeal edema. The erratic nature of the attacks with variations in clinical course and severity of symptoms among different patients and in one patient throughout life constitutes a challenge in the care of patients with hereditary angioedema. The main type of hereditary angioedema results from more than 700 pathogenic variants of the SERPING1 gene with functional or quantitative deficiency of the C1 inhibitor protein, but in recent years other mutations have been described in six other genes. Important advances have been made in the pathophysiology of the disease, and new drugs for the treatment of hereditary angioedema have been developed. In this context, the Brazilian Study Group on Hereditary Angioedema (GEBRAEH) in conjunction with the Brazilian Association of Allergy and Immunology (ASBAI) updated the Brazilian guidelines on hereditary angioedema. Greater knowledge of different aspects resulted in the division of the guidelines into two parts, with definition, classification, and diagnosis being addressed in this first part.

Diretrizes brasileiras de angioedema hereditário 2022 ­ Parte 2: terapêutica / 2022 Brazilian guidelines for hereditary angioedema ­ Part 2: therapy

O tratamento do angioedema hereditário tem início com a educação dos pacientes e familiares sobre a doença, pois é fundamental o conhecimento da imprevisibilidade das crises, assim como os seus fatores desencadeantes. O tratamento medicamentoso se divide em terapia das crises e profilaxia das manifestações clínicas. As crises devem ser tratadas o mais precocemente possível com o uso do antagonista do receptor de bradicinina, o icatibanto ou o concentrado de C1-inibidor. É necessário estabeler um plano de ação em caso de crises para todos os pacientes. A profilaxia de longo prazo dos sintomas deve ser realizada preferencialmente com medicamentos de primeira linha, como concentrado do C1-inibidor ou o anticorpo monoclonal anti-calicreína, lanadelumabe. Como segunda linha de tratamento temos os andrógenos atenuados. Na profilaxia de curto prazo, antes de procedimentos que podem desencadear crises, o uso do concentrado de C1-inibidor é preconizado. Existem algumas restrições para uso desses tratamentos em crianças e gestantes que devem ser consideradas. Novos medicamentos baseados nos avanços do conhecimento da fisiopatologia do angioedema hereditário estão em desenvolvimento, devendo melhorar a qualidade de vida dos pacientes. O uso de ferramentas padronizadas para monitorização da qualidade de vida, do controle e da atividade da doença são fundamentais no acompanhamento destes pacientes. A criação de associações de pacientes e familiares de pacientes com angioedema hereditário tem desempenhado um papel muito importante no cuidado destes pacientes no nosso país.

The treatment of hereditary angioedema begins with the education of patients and their families about the disease, as it is essential to know the unpredictability of attacks as well as their triggering factors. Drug treatment is divided into attack therapy and prophylaxis of clinical manifestations. Attacks should be treated as early as possible with the bradykinin receptor antagonist icatibant or C1-inhibitor concentrate. An action plan needs to be established for all patients with attacks. Long-term prophylaxis of symptoms should preferably be performed with first-line drugs such as C1-inhibitor concentrate or the anti-kallikrein monoclonal antibody lanadelumab. Attenuated androgens are the second line of treatment. In short-term prophylaxis, before procedures that can trigger attacks, the use of C1-inhibitor concentrate is recommended. There are some restrictions for the use of these treatments in children and pregnant women that should be considered. New drugs based on advances in knowledge of the pathophysiology of hereditary angioedema are under development and are expected to improve patient quality of life. The use of standardized tools for monitoring quality of life and controlling disease activity is essential in the follow-up of these patients. The creation of associations of patients and families of patients with hereditary angioedema has played a very important role in the care of these patients in Brazil.

Guia prático de urticária para grupos especiais de pacientes / Practical guide to urticaria for special patient groups

A urticária crônica é uma condição que afeta mais de um milhão de brasileiros, com grande impacto na qualidade de vida. Mesmo com diretrizes bem difundidas para o seu diagnóstico e tratamento, seu manejo pode ser desafiador em pacientes pediátricos, idosos e gestantes. Para auxiliar o médico especialista nestes casos, o Departamento Científico de Urticária da Associação Brasileira de Alergia e Imunologia elaborou esta revisão com as principais dúvidas e dificuldades referentes ao tema nestes grupos de pacientes.

Chronic urticaria is a condition that affects more than a million Brazilians with a significant impact on quality of life. Although there are well-established guidelines for diagnosis and treatment, the management of chronic urticaria may be challenging in pediatric, older, and pregnant patients. With the purpose of helping specialists manage these cases, the Urticaria Scientific Department of the Brazilian Association of Allergy and Immunology prepared this review with the most common doubts and difficulties about this topic in those patient groups.

Guia prático de urticária aguda / Practical guide to acute urticaria

A urticária aguda é uma causa frequente de consulta com alergistas, caracterizada por urticas e/ou angioedema. Embora autolimitada e benigna, pode causar desconforto significativo e raramente representar uma doença sistêmica grave ou reação alérgica com risco de vida. Nesta revisão, elaborada pelo Departamento Científico de Urticária da Associação Brasileira de Alergia e Imunologia, foram abordadas as principais questões referentes ao tema para auxiliar o médico especialista e generalista.

Acute urticaria is a frequent cause of consultations with allergists, being characterized by wheals and/or angioedema. Although self-limited and benign, it may cause significant discomfort and uncommonly represent a serious systemic disease or life-threatening allergic reaction. In this review prepared by the Urticaria Scientific Department of the Brazilian Association of Allergy and Immunology, the main questions about this topic are addressed to help specialists and general practitioners.

Hereditary angioedema in children and adolescents

Hereditary angioedema is a genetic disease with autosomal dominant inheritance and, in most cases, caused by C1 inhibitor deficiency. Patients present with recurrent edema affecting sub-cutaneous and mucus membranes with variable onset and severity. More than 50% of patients may become symptomatic before 10 years of age. Family history can help with the diagnosis; however, approximately 25% of the cases are de novo mutations. Biochemical diagnosis should be delayed until after 1 year of age. Children were often excluded from advances in therapy for hereditary angioedema since most of the new medicines were tested in adults and thus excluded by the Food and Drug Administration (FDA) and other agencies for approval to be used in children. Treatment of attacks is available for the pediatric patient; however, barriers still exist for the use of long-term prophylaxis in young children. © 2022 Codon Publications. Published by Codon Publications (AU)

Contact and intrinsic coagulation pathways are activated and associated with adverse clinical outcomes in COVID-19.

Coagulation activation is a prominent feature of severe acute respiratory syndrome coronavirus 2 (COVID-19) infection. Activation of the contact system and intrinsic pathway has increasingly been implicated in the prothrombotic state observed in both sterile and infectious inflammatory conditions. We therefore sought to assess activation of the contact system and intrinsic pathway in individuals with COVID-19 infection. Baseline plasma levels of protease:serpin complexes indicative of activation of the contact and intrinsic pathways were measured in samples from inpatients with COVID-19 and healthy individuals. Cleaved kininogen, a surrogate for bradykinin release, was measured by enzyme-linked immunosorbent assay, and extrinsic pathway activation was assessed by microvesicle tissue factor-mediated factor Xa (FXa; MVTF) generation. Samples were collected within 24 hours of COVID-19 diagnosis. Thirty patients with COVID-19 and 30 age- and sex-matched controls were enrolled. Contact system and intrinsic pathway activation in COVID-19 was demonstrated by increased plasma levels of FXIIa:C1 esterase inhibitor (C1), kallikrein:C1, FXIa:C1, FXIa:α1-antitrypsin, and FIXa:antithrombin (AT). MVTF levels were also increased in patients with COVID-19. Because FIXa:AT levels were associated with both contact/intrinsic pathway complexes and MVTF, activation of FIX likely occurs through both contact/intrinsic and extrinsic pathways. Among the protease:serpin complexes measured, FIXa:AT complexes were uniquely associated with clinical indices of disease severity, specifically total length of hospitalization, length of intensive care unit stay, and extent of lung computed tomography changes. We conclude that the contact/intrinsic pathway may contribute to the pathogenesis of the prothrombotic state in COVID-19. Larger prospective studies are required to confirm whether FIXa:AT complexes are a clinically useful biomarker of adverse clinical outcomes.

Acquired Angioedema due to C1-Inhibitor Deficiency: A Challenging Condition.

BACKGROUND: Acquired deficiency of C1 inhibitor (AAE-C1-INH) is a very rare cause of recurrent angioedema, with few cases reported in the literature. We aimed to describe a series of patients with AAE-C1-INH who were diagnosed and received care at angioedema reference centers in Brazil, affiliated to the Brazilian Group of Studies on Hereditary Angioedema. METHODS: Fourteen patients from 8 Brazilian Angioedema Reference Centers, diagnosed with AAE-C1-INH, were included in this study. Clinical data collected included sex, date of birth, date of onset of symptoms, date of diagnosis, plasma levels of antigenic and/or functional C1-INH, levels of C4 and C1q, location and treatment of angioedema attacks, long-term prophylaxis, associated diseases, and definitive treatment. RESULTS: Fourteen patients were identified with AAE-C1-INH. Most patients (10/14; 71.4%) were female. The median age at onset of symptoms was 56.5 years (range, 14-74 years; interquartile range [IQR], 32-64 years), and median age at diagnosis was 58.0 years (range, 20-76 years; IQR, 38-65 years), with a median time until diagnosis of 2 years (range, 0-6 years; IQR, 1-3 years). The most common manifestations were cutaneous (face, eyelids, lips, trunk, hands, feet, and genitals). Most patient had low levels of C4 (13/14; 92.8%) and of antigenic C1-INH (8/14; 57.1%). Four had decreased functional activity of C1-INH (4/7; 57.1%) and C1q levels were low in 5 patients (5/12; 41.6%). Underlying diseases were identified in all 14 patients, with lymphoma of the splenic marginal zone and monoclonal gammopathy of undetermined significance being the most frequent. Nine patients (64.2%) needed long-term prophylactic treatment for recurrent angioedema and 5 patients (46.7%) required treatment for angioedema attacks. Most of them (12/14; 85.7%) had resolution of angioedema. CONCLUSION: Therapy of AAE-C1-INH aims to control symptoms; however, diagnosis and treatment of the underlying disease, when present, should be an important target and may lead to the resolution of angioedema in patients with AAE-C1-INH.