Systemic inflammation biomarkers during angioedema attacks in hereditary angioedema.

Background: Hereditary angioedema (HAE) is a rare disease characterized by localized and self-limited angioedema (AE) attacks. A local increase of bradykinin (BK) mediates AE attacks in HAE, however the role of inflammation in HAE has been poorly explored We aim to analyze the role of inflammatory mediators in HAE patients during AE attacks. Methods: Patients with a confirmed HAE diagnosis due to C1 inhibitor deficiency (HAE-C1INH) or patients F12 gene mutations (HAE-FXII) attending to our outpatient clinic between November-2019 and May-2022 were included. Demographic and clinical characteristics were analyzed. Blood samples were collected both during symptom-free periods (baseline) and during HAE attacks, and acute phase reactants (APR), such as serum amyloid A (SAA), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), D-Dimer and white blood cells were measured. Results: Seventy-eight patients were enrolled in the study, with a predominant representation of women (76%, n=59), and a mean age of 47.8 years (range 6-88). Among them, 67% (n=52) of patients had HAE-C1INH (46 classified as type 1 and 6 as type 2) while 33% (n=26) had HAE-FXII. During attack-free periods, the majority of patients exhibited normal levels of SAA, ESR, D-dimer, ACE and WCC. However, in a subset of patients (16% for SAA, 18% for ESR, and 14.5% for D-dimer), elevations were noted at baseline. Importantly, during HAE attacks, significant increases were observed in SAA in 88% of patients (p< 0.0001 vs. baseline), in ESR in 65% (p= 0.003 vs. baseline) and D-dimer in 71% (p=0.001 vs. baseline) of the patients. A comparison between baseline and acute attack levels in 17 patients revealed significant differences in SAA AA (p<0. 0001), ESR (p<0.0001) and D-dimer (p= 0.004). No significant differences were observed in CRP (p=0.7), ACE (p=0.67) and WCC (p=0.54). These findings remained consistent regardless of HAE type, disease activity or location of angioedema. Conclusion: The systemic increase in APR observed during HAE attacks suggests that inflammation extends beyond the localized edematous area. This finding underscores the potential involvement of inflammatory pathways in HAE and highlights the need for further investigation into their role in the pathophysiology of HAE.

[Pedigree Analysis of Hereditary Coagulation Factor XII Deficiency Caused by Compound Heterozygous Mutation p.Gly175Cys and p.Gly542Ser of F12 Gene].

OBJECTIVE: To analyze the clinical phenotype and gene mutation of a genetic coagulation factor XII (FXII) deficiency pedigree and explore the molecular pathogenesis. METHODS: The activated partial thromboplastin time (APTT) and FXII activity (FXII:C) were detected by clotting method. The FXII antigen (FXII:Ag) was tested with ELISA. All exons and flanks of F12 gene were determined by Sanger sequencing. ClustalX-2.1-win, PROVEAN and Swiss-Pdb Viewer software were used to analyze the conservatism of amino acids at the mutant site, forecast whether the mutant amino acids were harmful and confirm the influence of the mutation on protein structure. RESULTS: The APTT of the proband prolonged to 71.3 s. The FXII:C and FXII:Ag were decreased to 5% and 6%, respectively. There were two heterozygous missense mutations c.580G>T and c.1681G>A detected in exon 7 and exon 14 of F12 gene, resulting in p.Gly175Cys and p.Gly542Ser, severally. Proband's father carried the p.Gly175Cys heterozygous mutation, while mother, brother and daughter had the p.Gly542Ser heterozygous mutation. Software analysis showed that both Gly175 and Gly542 were conserved, the two mutations were harmful and when mutations had occurred, the corresponding sites affected the protein local structure. CONCLUSION: The p.Gly175Cys and p.Gly542Ser compound heterozygous mutations are the molecular pathogenesis of the hereditary coagulation FXII deficiency pedigree. The p.Gly175Cys mutation has been detected for the first time in the world.

Hereditary angioedema with normal C1-inhibitor: Clinical and genetic characterization of 15 Portuguese unrelated families.

BACKGROUND: Hereditary angioedema with normal C1-inhibitor (HAE-nC1-INH) is a rare genetic disease with similar phenotype to HAE-C1-INH but different genetic background. Currently, 6 subtypes are recognized, based on the underlying mutations. Several aspects need further clarification. OBJECTIVE: To assess clinical features of patients with genetically characterized HAE-nC1-INH from the North of Portugal. METHODS: Retrospective assessment of clinical data from all patients with HAE-nC1-INH followed at a HAE Reference Center. RESULTS: A total of 41 patients were identified, 4 with no family history. The FXII mutation Thr328Lys (38 carriers) was the most prevalent. There were 3 new potentially disease-causing variants linked to HAE-nC1-INH identified (c.529+4A>G:FXII; Cys248*:Kininogen-1; and Arg261His:Plasminogen). The HAE-FXII cohort included 82% females and 71.8% symptomatic patients. Penetrance rate was significantly higher in females (81.3% vs 28.6%; P = .012). A hormonal influence was observed in 96.2% of the symptomatic females, although 62.5% remained symptomatic after oral estrogen withdrawal. Trauma and dental procedures were frequent triggers (82.6% and 45.5%, respectively). Main locations were facial (described by 96%), lips (82.1%), and eyelids (64.3%). One patient reported erythema marginatum as prodrome. Plasma-derived C1-INH was effective as short-term prophylaxis in all treated patients, but only in 80% as on-demand treatment. Icatibant was effectively used on demand in 9 patients, but with relapses in 5 (57%). CONCLUSION: We described a large Portuguese series of patients with HAE-nC1-INH genetically characterized. Differences with others may contribute to improve current unmet needs and raise awareness of this rare disease. We highlighted the identification of 3 new variants (additional molecular studies are ongoing) and the report of erythema marginatum in HAE-nC1-INH.

A clinical evaluation of patients with known mutations (plasminogen and factor XII) with a focus on prophylactic treatment.

BACKGROUND: Hereditary angioedema with normal C1-inhibitor (HAE-nC1-INH) is a rare genetic disease. The symptoms can resemble other forms of hereditary angioedema (HAE), but the specific laboratory values are inconspicuous. The knowledge about treatment strategies in HAE-nC1-INH remains insufficient; most of the drugs are only licensed and approved for other types of HAE. METHODS: An analysis of all patients with HAE-nC1-INH was carried out in a certified angioedema treatment center in southern Germany. Only patients with a confirmed HAE-nC1-INH mutation were included. The impact of disease was monitored with validated questionnaires. RESULTS: Eighteen patients were included: two families with a factor XII mutation and seven families with a plasminogen mutation. All individuals received icatibant for on-demand therapy-efficient treatment response was reported. Three patients were severely affected, and prophylaxis was initiated with lanadelumab. According to the questionnaires, the clinical course and symptoms improved significantly under this prophylactic regime. CONCLUSION: This is one of the first descriptions of the clinical outcomes as a response to prophylactic treatment with lanadelumab in HAE-nC1-INH patients with a known mutation. The therapeutic management of HAE-1 and HAE-2 should also be the basis of HAE-nC1-INH, including prophylaxis.

Analysis of F12 gene variants and molecular mechanisms in patients with coagulation factor Ⅻ deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the sequence of the F12 gene and molecular mechanism for 20 patients with coagulation factor Ⅻ (FⅫ) deficiency.@*METHODS@#The patients were selected from the outpatient department of the Second Hospital of Shanxi Medical University from July 2020 to January 2022. The activity of coagulation factor Ⅷ (FⅧ:C), factor Ⅸ (FⅨ:C), factor Ⅺ (FⅪ:C) and factor Ⅻ (FⅫ:C) were determined by using a one-stage clotting assay. All exons and 5' and 3' UTR of the F12 gene were analyzed by Sanger sequencing to detect the potential variants. Bioinformatic software was used to predict the pathogenicity of the variants, conservation of amino acids, and protein models.@*RESULTS@#The FⅫ:C of the 20 patients has ranged from 0.07% to 20.10%, which was far below the reference values, whilst the other coagulation indexes were all normal. Sanger sequencing has identified genetic variants in 10 patients, including 4 with missense variants [c.820C>T (p.Arg274Cys), c.1561G>A (p.Glu521Lys), c.181T>C (p.Cys61Arg) and c.566.G>C (p.Cys189Ser)], 4 deletional variants c.303_304delCA(p.His101GlnfsX36), 1 insertional variant c.1093_1094insC (p.Lys365GlnfsX69) and 1 nonsense variant c.1763C>A (p.Ser588*). The remaining 10 patients only harbored the 46C/T variant. The heterozygous c.820C>T(p.Arg274Cys) missense variant in patient 1 and the homozygous c.1763C>A (p.Ser588*) nonsense variant in patient 2 were not included in the ClinVar and the Human Gene Mutation Database. Bioinformatic analysis predicted that both variants were pathogenic, and the corresponding amino acids are highly conserved. The protein prediction models suggested that the c.820C>T (p.Arg274Cys) variant may affect the stability of the secondary structure of FⅫ protein by disrupting the original hydrogen bonding force and truncating the side chain, leading to changes in the vital domain. c.1763C>A (p.Ser588*) may produce a truncated C-terminus which may alter the spatial conformation of the protein domain and affect the serine protease cleavage site, resulting in extremely reduced FⅫ:C.@*CONCLUSION@#Among individuals with low low FⅫ:C detected by one-stage clotting assay, 50% have harbored variants of the F12 gene, among which the c.820C>T and c.1763C>A were novel variants underlying the reduced coagulating factor FⅫ.

Genetic analysis of a Chinese pedigree affected with Congenital coagulation factor XII deficiency due to a c.1A>G start codon variant of F12 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics and genetic etiology of a consanguineous Chinese pedigree affected with Congenital coagulation factor XII (XII) deficiency.@*METHODS@#Members of the pedigree who had visited Ruian People's Hospital on July 12, 2021 were selected as the study subjects. Clinical data of the pedigree were reviewed. Peripheral venous blood samples were taken from the subjects. Blood coagulation index and genetic testing were carried out. Candidate variant was verified by Sanger sequencing and bioinformatic analysis.@*RESULTS@#This pedigree has comprised 6 individuals from 3 generations, including the proband, his father, mother, wife, sister and son. The proband was a 51-year-old male with kidney stones. Blood coagulation test showed that his activated partial thromboplastin time (APTT) was significantly prolonged, whilst the FXII activity (FXII:C) and FXII antigen (FXII:Ag) were extremely reduced. The FXII:C and FXII:Ag of proband's father, mother, sister and son have all reduced to about half of the lower limit of reference range. Genetic testing revealed that the proband has harbored homozygous missense variant of c.1A>G (p.Arg2Tyr) of the start codon in exon 1 of the F12 gene. Sanger sequencing confirmed that his father, mother, sister and son were all heterozygous for the variant, whilst his wife was of the wild type. By bioinformatic analysis, the variant has not been included in the HGMD database. Prediction with SIFT online software suggested the variant is harmful. Simulation with Swiss-Pbd Viewer v4.0.1 software suggested that the variant has a great impact on the structure of FXII protein. Based on the Standards and Guidelines for the Interpretation of Sequence Variants: A Joint Consensus Recommendation of the American College of Medical Genetics and Genomics (ACMG), the variant was rated as likely pathogenic.@*CONCLUSION@#The c.1A>G (p.Arg2Tyr) variant of the F12 gene probably underlay the Congenital FXII deficiency in this pedigree. Above finding has further expanded the spectrum of F12 gene variants and provided a reference for clinical diagnosis and genetic counseling for this pedigree.

Analysis of a Chinese pedigree affected with Hereditary FⅫ deficiency due to compound heterozygous variants of F12 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the laboratory phenotype and molecular pathogenesis in a Chinese pedigree affected with Hereditary coagulation factor Ⅻ (FⅫ) deficiency.@*METHODS@#A male proband admitted to Ningbo No.2 Hospital on July 17, 2021 due to chronic gastritis and members of his pedigree (7 individuals from three generations) were selected as the study subjects. Prothrombin time (PT), activated partial thromboplastin time (APTT), FⅧ activity (FⅧ: C), FⅨ activity (FⅨ: C), FⅪ activity (FⅪ: C), FⅫ activity (FⅫ: C), and FⅫ antigen (FⅫ: Ag) were determined. All of the exons, exon-intronic boundaries, as well as the 5'- and 3'-untranslated regions of the F12 gene were subjected to Sanger sequencing. Candidate variants were verified by cloning sequencing. The effect of candidate variants on the protein function was analyzed by bioinformatics software.@*RESULTS@#The proband, a 47-year-old male, had significantly prolonged APTT (180.0 s) and decreased FⅫ:C and FⅫ:Ag levels (< 1%). His father, mother, brother and two sons also showed certain degrees of reduction. Genetic testing revealed that the proband has harbored compound heterozygous variants of the F12 gene, namely c.1092_1093insC (p.Lys365Glnfs*69) in exon 10 and c.1792_1796delGTCTA (p.Val579Hisfs*32) in exon 14. His mother and elder son were heterozygous for the c.1092_1093ins variant, whilst his father, brother, and younger son were heterozygous for the c.1792_1796delGTCTA variant. Analysis of the promoter region of exon 1 also showed that the proband and both sons had harbored a 46T/T polymorphism, whilst other family members were 46C/T. Bioinformatic analysis suggested that the p.Val579 is a highly conserved site. Protein model analysis showed that, with the p.Val579Hisfs*32 variant, a benzene ring was added and the hydrogen bond of surrounding amino acids was changed. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.1792_1796delGTCTA was classified as a pathogenic variant (PVS1+PM2_Supporting+PM4).@*CONCLUSION@#The c.1092_1093insC (p.Lys365Glnfs*69) and c.1792_1796delGTCTA (p.Val579Hisfs*32) compound heterozygous variants of the F12 gene probably underlay the decreased FXII levels in this pedigree. Above finding has also enriched the mutational spectrum for FⅫ deficiency.

Analysis of a Chinese pedigree affected with Hereditary coagulation factor Ⅻ deficiency due to compound heterozygous variants of F12 gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical phenotypes and genetic variants of a Chinese pedigree affected with Hereditary coagulation factor Ⅻ (FⅫ) deficiency.@*METHODS@#A pedigree presented at the First Affiliated Hospital of Air Force Medical University on December 24,2021 was selected as the study subject. Activated partial thromboplastin time (APTT) and coagulation factor Ⅻ activity (FⅫ:C) were determine by a clotting method, and FⅫ antigen was detected with an ELISA assay. Following the extraction of genomic DNA, all exons and flanking regions of the F12 gene were subjected to Sanger sequencing. Clustalx-2.1-win, PROVEAN and Swiss-PDB Viewer software was used to analyze the conservation of amino acids at the variant sites, impact of of the variants on the amino acid substitutions and the protein structure.@*RESULTS@#The APTT of the proband has prolonged to 70.2 s. Her FⅫ:C and FⅫ:Ag have decreased to 12% and 13%, respectively. DNA sequencing revealed that the proband has harbored c.346G>A (p.Gly97Ser) and c.1583C>A (p.Ser509Tyr) heterozygous compound missense variants in exons 5 and 13 of the F12 gene, respectively. Her father and sister were heterozygous carriers for the c.346G>A (p.Gly97Ser) variant, whilst her mother and brother were heterozygous for the c.1583C>A (p.Ser509Tyr) variant.@*CONCLUSION@#The c.346G>A (p.Gly97Ser) and c.1583C>A (p.Ser509Tyr) compound heterozygous variants of the F12 gene probably underlay the pathogenesis of hereditary coagulation FⅫ deficiency in this pedigree.

Trombosis venosa portal como manifestación de una mutación del Factor XII / Portal vein thrombosis as a manifestation of a factor XII mutation

La trombosis venosa abdominal es una forma poco común de enfermedad tromboembólica venosa en niños. Si bien las tasas de mortalidad son bajas, una proporción significativa de niños afectados pueden sufrir morbilidad a largo plazo. Entre sus etiologías, se sabe que existe asociación con trastornos protrombóticos, siendo poco frecuente la ausencia del factor XII. El tratamiento incluye anticoagulación y la resección quirúrgica de los órganos isquémicos con potencial trasplante posterior (AU)

Abdominal venous thrombosis is a rare form of venous thromboembolic disease in children. Although the associated mortality is low, a significant proportion of affected children suffer from long-term morbidity. Among its aetiologies, there is evidence of an association with prothrombotic disorders, absence of factor XII being an infrequent one. Treatment includes anticoagulant medication and surgical resection of the ischaemic organs, potentially followed by transplantation. (AU)

Analysis of A Pedigree with Hereditary Coagulation Factor Ⅻ Deficiency Caused by Compound Heterozygous Mutations / 中国实验血液学杂志

OBJECTIVE@#To analysis clinical phenotype and potential genetic cause of a family affected with hereditary coagulation factor Ⅻ deficiency.@*METHODS@#The prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), D-Dimer (D-D), coagulation factor Ⅻ activity (FⅫ:C) and coagulation factor Ⅻ antigen (FⅫ:Ag) were determined for phenotype diagnosis of the proband and his family members(3 generations and 5 people). Targeted capture and whole exome sequencing were performed in peripheral blood sample of the proband. Possible disease-causing mutations of F12 gene were obtained and further confirmed by Sanger sequencing. The corresponding mutation sites of the family members were analyzed afterwards. The online bioinformatics software AutoPVS1 and Mutation Taster was used to predict the effects of mutation sites on protein function.@*RESULTS@#The APTT of the proband was significantly prolonged, reaching 180.9s. FⅫ:C and FⅫ:Ag of the proband was significantly reduced to 0.8% and 4.17%, respectively. The results of whole exome sequencing displayed that there were compound heterozygous mutations in F12 gene of the proband, including the c.1261G＞T heterozygous nonsense mutation in exon 11 (causing p.Glu421*) and the c.251dupG heterozygous frameshift mutation in exon 4 (causing p.Trp85Metfs*53). Both mutations are loss of function mutations with very strong pathogenicity, leading to premature termination of the protein. AutoPVS1 and Mutation Taster software predicted both mutations as pathogenic mutations. The results of Sanger sequencing revealed that c.1261G＞T heterozygous mutation of the proband was inherited from his mother, for which his brother and his daughter were c.1261G＞T heterozygous carriers. Genotype-phenotype cosegregation was observed in this family.@*CONCLUSION@#The c.1261G＞T heterozygous nonsense mutation in exon 11 and the c.251dupG heterozygous frameshift mutation in exon 4 of the F12 gene probably account for coagulation factor Ⅻ deficiency in this family. This study reports two novel pathogenic F12 mutations for the first time worldwide.

Short-term prophylaxis for delivery in pregnant women with hereditary angioedema with normal C1-inhibitor / Profilaxia de curto prazo para o parto em grávidas com angioedema hereditário com inibidor de C1 normal

Abstract Objective To verify the efficacy of short-term prophylaxis for vaginal or cesarean section childbirth with plasma-derived C1-inhibitor concentrate in pregnant women. They should have hereditary angioedema (HAE) and normal plasma C1-inhibitor. Methods Case report of pregnant women diagnosed with HAE with normal C1- inhibitor who had been treated with intravenous C1-inhibitor concentrate for prophylaxis of angioedema attacks when hospitalized for delivery. The exon 9 of the Factor 12 (F12) genotyping gene was performed by automatic sequencing in all patients. Results Three cases of pregnant women with HAE with normal serum level of C1- inhibitor are reported. The genetic test detected the presence of a pathogenic mutation in the F12 gene. Deliveries occurred uneventfully and patients had no HAE symptoms in the following 72 hours. Conclusion C1-inhibitor concentrate could be useful to prevent angioedema attacks during and after delivery.

Resumo Objetivo Verificar a eficácia da profilaxia de curto prazo para o parto vaginal ou cesáreo com inibidor de C1 derivado de plasma concentrado em mulheres grávidas. Eles devem ter angioedema hereditário e inibidor normal de C1 no plasma. Métodos Relato de caso de gestantes diagnosticadas com angioedema hereditário com inibidor de C1 normal que foram tratadas com inibidor intravenoso de concentrado de C1 para profilaxia de ataques de angioedema quando hospitalizadas para o parto. O exon 9 do gene de genotipagem do fator 12 (F12) foi realizado por sequenciamento automático em todos os pacientes. Resultados Três casos de gestantes com angioedema hereditário com nível sérico normal de inibidor de C1 são relatados. O teste genético detectou a presença de uma mutação patogênica no gene F12. Os partos ocorreram sem intercorrências e as pacientes não apresentaram sintomas hereditários de angioedema nas 72 horas seguintes. Conclusão O concentrado de inibidor de C1 pode ser útil para prevenir ataques de angioedema durante e após o parto.

Polimorfismos en la región Kozak del FXII y su relación con el infarto agudo de miocardio prematuro / Polymorphisms in Kozak region of FXII and their relationship with premature acute myocardial infarction

Introducción/objetivos. El factor XII desempeña un papel fundamental tanto en la coagulación como en la fibrinólisis; sin embargo, se desconoce la relevancia patológica de su deficiencia. El polimorfismo C46T, localizado en la región Kozak de este gen, se asocia con menores valores plasmáticos de factor XII al afectar la traducción del ARNm. Nuestro objetivo fue evaluar el papel de este polimorfismo en alteraciones trombóticas y hemorrágicas. Pacientes y métodos. Realizamos 3 estudios de casos y controles, que incluyeron a 55 pacientes con hemorragia intracraneal espontánea, 206 con trombosis venosa profunda, y 281 con infarto agudo de miocardio prematuro (infarto agudo de miocardio < 45). Los controles (n = 550) fueron sujetos sanos de la misma zona geográfica. La determinación del polimorfismo se realizó mediante reacción en cadena de la polimerasa y análisis de conformación de cadenas sencillas. El genotipo se confirmó mediante secuenciación. Resultados. El polimorfismo C46T no modifica significativamente el riesgo de presentar hemorragia intracraneal espontánea o trombosis venosa profunda. Sin embargo, el alelo 46T aparece como factor de riesgo débil para el desarrollo de infarto agudo de miocardio < 45 (odds ratio ajustada = 1,64; intervalo de confianza del 95%, 1,14-2,37; p = 0,008). Los portadores del alelo 46T mostraron valores de proteína C reactiva superiores (p = 0,002) y peor evolución que los controles. Además, encontramos un sinergismo entre la hipercolesterolemia y este polimorfismo. Finalmente, describimos una nueva variante genética en el gen que codifica el factor XII (C42T), infrecuente, cercana a la secuencia Kozak y posiblemente ligada a la variante 46C, pero que no parece afectar a los valores circulantes de factor XII. Conclusiones. El alelo 46T, asociado con menores valores plasmáticos de factor XII, parece predisponer al desarrollo de infarto agudo de miocardio prematuro, especialmente en pacientes hipercolesterolémicos

Introduction/Aim. Factor XII (FXII) plays a key role in both coagulation and fibrinolysis. However, the pathological importance of FXII deficiency remains unknown. The C46T polymorphism in the Kozak region of gene coding FXII is related to lower FXII plasma levels by mRNA translation alterations. Our aim was to assess the role of this polymorphism in thrombotic and hemorrhagic disease. Patients and methods. We performed 3 case-control studies including 55 patients with spontaneous intracranial hemorrhage (SIH), 206 with deep venous thrombosis (DVT) and 281 with premature myocardial infarction (AMI < 45). Controls (n = 550) were healthy subjects from the same geographic area. Polymorphism identification was performed by PCR and single-stranded conformational polymorphism (SSCP) analysis. Genotype was confirmed by sequencing. Results. The C46T polymorphism modifies neither the risk for SIH nor for DVT. Nevertheless, the 46T allele arises as a weak risk factor for the development of AMI < 45 (adjusted OR = 1.64; 95% CI, 1.14-2.37; p = 0.008). Allele 46T carriers showed higher CRP levels (p = 0.002) and worse outcome than controls. Moreover, we found a synergic interaction between hypercholesterolemia and this polymorphism. Finally, we described a new genetic variant in the gene coding FXII: C42T, found rarely, close to the Kozak sequence and possibly linked to the 46C variant, which, however, does not seem to affect FXII circulating levels