Novel hereditary angioedema linked with a heparan sulfate 3-O-sulfotransferase 6 gene mutation

Background Hereditary angioedema (HAE) is a potentially fatal disorder resulting in recurrent attacks of severe swelling. It may be associated with a genetic deficiency of functional C1 inhibitor or with normal C1 inhibitor (HAEnCI). In families with HAEnCI, HAE-linked mutations in the F12, PLG, KNG1, ANGPT1, or MYOF genes have been identified. In many families with HAEnCI the genetic cause of the disease is currently unknown. Objective The aim of this study was to identify a novel disease-linked mutation for HAEnCI. Methods The study methods comprised whole exome sequencing, Sanger sequencing analysis, pedigree analysis, bioinformatic analysis of the mutation, and biochemical analysis of p…

Tamoxifen may cause life-threatening angioedema attacks in patients with hereditary angioedema

On the pathogenicity of the plasminogen K330E mutation for hereditary angioedema

Treatment for hereditary angioedema with normal C1-INH and specific mutations in the F12 gene (HAE-FXII).

Hereditary angioedema with normal C1 esterase inhibitor and mutations in the F12 gene (HAE-FXII) is associated with skin swellings, abdominal pain attacks, and the risk of asphyxiation due to upper airway obstruction. It occurs nearly exclusively in women. We report our experience treating HAE-FXII with discontinuation of potential trigger factors and drug therapies. The study included 72 patients with HAE-FXII. Potential triggers included estrogen-containing oral contraceptives (eOC), hormonal replacement therapy, or angiotensin-converting enzyme inhibitors. Drug treatment comprised plasma-derived C1 inhibitor (pdC1-INH) for acute swelling attacks and progestins, tranexamic acid, and danaz…

Hereditary angioedema with normal C1-INH withversuswithout specificF12gene mutations

Background Hereditary angioedema with normal C1-INH may be linked to specific mutations in the coagulation factor 12 (FXII) gene (HAE-FXII) or mutations in genes that are still unknown (HAE-unknown). To assess the differences in transmission and inheritance, clinical features, and laboratory parameters between patients with HAE-FXII and HAE-unknown. Methods Sixty-nine patients with HAE-FXII from 23 unrelated families and 196 patients with HAE-unknown from 65 unrelated families were studied. Results Both HAE-FXII and HAE-unknown are inherited as autosomal-dominant traits with incomplete penetrance. The male to female ratio was 1 : 68 in HAE-FXII and 1 : 6.3 in HAE-unknown. The maternal to pa…

Antihistamine-resistant Angioedema in Women with Negative Family History: Estrogens and F12 Gene Mutations

Abstract Background In women with sporadic recurrent angioedema with an unknown cause who are unresponsive to antihistamines and have normal C1 inhibitor activity and a negative family history of angioedema, it is unclear whether they have idiopathic angioedema or hereditary angioedema with normal C1 inhibitor, and what impact exogenous estrogens have on their angioedema. Methods A cohort of 147 women was analyzed for F12 exon 9 mutations and for the influence of oral contraceptives, hormonal replacement therapy, and pregnancy on their angioedema. Results A total of 142 women had idiopathic angioedema unresponsive to antihistamines. Five women had an F12 mutation and thereby hereditary angi…

A novel mutation in the coagulation factor 12 gene in subjects with hereditary angioedema and normal C1-inhibitor.

In hereditary angioedema with normal C1-inhibitor two different missense mutations of codon p.Thr328* in the coagulation factor 12 gene have been reported in some families. In this study a novel factor 12 gene mutation, the deletion of 72 base pairs (bp) (c.971_1018+24del72*), was identified in a family of Turkish origin, in two sisters with recurrent skin swellings and abdominal pain attacks and in their symptom-free father. This deletion caused a loss of 48 bp of exon 9 (coding amino acids 324* to 340*) in addition to 24 bp of intron 9, including the authentic donor splice site of exon 9. The large deletion of 72 bp was located in the same F12 gene region as the missense mutations p.Thr32…

Mutations in the Factor XII Gene in Solitary Cases of Recurrent Angioedema with Normal C1 Inhibitor Induced or Worsened by Oral Contraceptives or Hormonal Replacement Therapy

Characterization of a partial exon 9/intron 9 deletion in the coagulation factor XII gene (F12) detected in two Turkish families with hereditary angioedema and normal C1 inhibitor

Hereditary angioedema with a mutation in the plasminogen gene

Background Hereditary angioedema (HAE) with normal C1-INH (HAEnCI) may be linked to specific mutations in the coagulation factor 12 (FXII) gene (HAE-FXII) or functional mutations in other genes that are still unknown. We sought to identify and characterize a hitherto unknown type of HAE with normal C1-INH and without mutation in the F12 gene. Methods The study comprised analysis of whole-exome sequencing, Sanger sequencing, and clinical data of patients. Results We detected a mutation in the plasminogen (PLG) gene in patients with HAEnCI. The mutation c.9886A>G was located in exon 9 leading to the missense mutation p.Lys330Glu (K330E) in the kringle 3 domain of the PLG protein. The mutation…

Fatal laryngeal attacks and mortality in hereditary angioedema due to C1-INH deficiency.

Background Hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH) is characterized by relapsing skin swellings, abdominal pain attacks, and, less frequently, potentially life-threatening laryngeal attacks. Objective This study determined the mortality of patients with and without the diagnosis of HAE-C1-INH and analyzed fatal laryngeal attacks. Methods A cohort of 728 patients from 182 families with HAE-C1-INH was evaluated for death cases by analyzing pedigrees. Detailed information on fatal laryngeal attacks in 36 patients was obtained by questioning relatives and treating physicians. Results Of the 214 patients who had died, 70 asphyxiated during a laryngeal attack. Mortality …

Shortened Activated Partial Thromboplastin Time May Help in Diagnosing Hereditary and Acquired Angioedema

<b><i>Objective:</i></b> To evaluate whether activated partial thromboplastin time (APTT) could be used in the laboratory diagnosis of hereditary or acquired angioedema (HAE or AAE) with and without C1 inhibitor (C1-INH) deficiency. <b><i>Methods:</i></b> In a prospective investigation, APTT and other coagulation parameters were determined in 149 adult patients with various types of angioedema and in 26 healthy participants (HP). <b><i>Results:</i></b> Mean APTT was significantly shortened in HAE-C1-INH type I (p < 0.0001) and type II (p = 0.0017) and in AAE-C1-INH (p < 0.0001) compared to the HP. APTT was shorten…

Blindness, tetraspasticity, and other signs of irreversible brain damage in hereditary angioedema

Hereditary angioedema cosegregating with a novel kininogen 1 gene mutation changing the N‐terminal cleavage site of bradykinin

Hereditary angioedema caused by missense mutations in the factor XII gene: clinical features, trigger factors, and therapy.

Background Hereditary angioedema caused by mutations in the factor XII gene is a recently described disease entity that occurs mainly in women. It differs from hereditary angioedema caused by C1 inhibitor deficiency. Objective To assess the clinical symptoms, factors triggering acute attacks, and treatments of this disease. Methods Thirty-five female patients with hereditary angioedema and the factor XII mutations p.Thr309Lys and p.Thr309Arg who came from 13 unrelated families were studied. The observation period was 8.4 years on average (range, 2-26 years). Results Patients had on average 12.7 ± 7.9 angioedema attacks per year. Recurrent facial swellings occurred in all patients; skin swel…

Kallikrein–kinin system and fibrinolysis in hereditary angioedema due to factor XII gene mutation Thr309Lys

In a subgroup of hereditary angioedema (HAE) patients with normal C1-esterase inhibitor levels, HAE is caused by a Thr309Lys mutation in the coagulation factor XII (F12) gene. The aim of this study was to examine elements of the kallikrein-kinin system ('contact system') and the downstream-linked coagulation, complement and fibrinolytic systems in the plasma of six patients with HAE caused by the Thr309Lys mutation and healthy probands. Blood samples were taken from participants during the symptom-free interval between attacks. Samples were analyzed for activity and concentrations of components of the kallikrein-kinin system and linked enzyme systems. The mean FXII clotting activity was 90%…