Molecular and clinical profile of congenital fibrinogen disorders in Iran, identification of two novel mutations

Introduction: Congenital fibrinogen disorders (CFDs) comprise the quantitative and qualitative fibrinogen molecule abnormalities that are caused by fibrinogen gene mutations. The objective of this cohort research was to study the molecular and clinical profiles of patients with CFDs. Materials and methods: Genomic DNA Sanger sequencing of 14 Iranian patients was performed to determine CFDs-causing mutations. The disorders were diagnosed by routine and specific (fibrinogen antigen and functional assay) coagulation tests, and clinical data were obtained from medical records. Molecular dynamics (MD) simulations were performed to investigate the effect of missense mutation on the protein structure. Results: Thirteen out of 14 patients had afibrinogenemia while the remaining patient had dysfibrinogenemia. Umbilical cord bleeding was the most common clinical presentation (n: 9, ~70) which led to the diagnosis of afibrinogenemia, while menorrhagia led to the diagnosis of dysfibrinogenemia. Six homozygous mutations were identified in afibrinogenemia: three previously described variants in FGA (p.Trp52Ter, p.Ser312AlafsTer109 and p.Gly316GlufsTer105), one in FBG (p.Gly430Asp), and two novel mutations in FGB (p.Gly430Arg) and FGG (p.His366ThrfsTer40), while the FGA (p.Arg38Thr) heterozygous mutation was identified in dysfibrinogenemia. MD simulation indicated that the FGA p. Arg38Thr mutation probably interferes with polymerization of fibrin monomers. Conclusions: In Iran, with its high rate of consanguinity, autosomal recessive afibrinogenemia with severe clinical presentations is relatively common due to heterogeneous molecular defects. © 2020 John Wiley & Sons Lt

Challenges and concerns of patients with congenital bleeding disorders affected by coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) is a new medical challenge for all individuals, especially for those with underlying disorders, such as congenital bleeding disorders (CBDs). Therefore, the pandemic might significantly change the behaviour of patients with CBDs and results in some challenges. In the present study, we assessed the main challenges of COVID-19 infection to patients with CBDs. Data were collected from medical files and interviews of patients with CBDs who had COVID-19 infection. Follow-ups were performed on patients who had active severe acute respiratory syndrome coronavirus 2 infection between April and October 2020. All patients were interviewed by an expert in order to collect the pertinent data. Some questions were about patients' preventive behaviors and feelings prior to infection, and some were about the consequences of infection on patients' replacement therapy and bleeding management. Among 25 patients, infection and death of loved ones (n: 7, 28), and their own (n: 5, 20) or family members' (n: 1, 4) infection, and the resulting economic burden (n: 2, 8) were main concerns. Six patients experienced depression during the pandemic. The pandemic caused all severely affected patients but one (n: 11, 92) to abandon replacement therapy. However, two received on-demand therapy after exacerbation of their bleeding. Only one (25) of four patients on prophylaxis received in-home therapy, whereas the others (75) abandoned prophylaxis. It seems that COVID-19 infection has great consequences on the lives of patients with CBDs, causing some to take dangerous actions, such as abandonment of their treatment. Healthcare systems, and healthcare providers, should have an appropriate strategy for management of patients with CBDs that prevents infection and provides timely replacement therapy. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved

Challenges and concerns of patients with congenital bleeding disorders affected by coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) is a new medical challenge for all individuals, especially for those with underlying disorders, such as congenital bleeding disorders (CBDs). Therefore, the pandemic might significantly change the behaviour of patients with CBDs and results in some challenges. In the present study, we assessed the main challenges of COVID-19 infection to patients with CBDs. Data were collected from medical files and interviews of patients with CBDs who had COVID-19 infection. Follow-ups were performed on patients who had active severe acute respiratory syndrome coronavirus 2 infection between April and October 2020. All patients were interviewed by an expert in order to collect the pertinent data. Some questions were about patients' preventive behaviors and feelings prior to infection, and some were about the consequences of infection on patients' replacement therapy and bleeding management. Among 25 patients, infection and death of loved ones (n: 7, 28%), and their own (n: 5, 20%) or family members' (n: 1, 4%) infection, and the resulting economic burden (n: 2, 8%) were main concerns. Six patients experienced depression during the pandemic. The pandemic caused all severely affected patients but one (n: 11, 92%) to abandon replacement therapy. However, two received on-demand therapy after exacerbation of their bleeding. Only one (25%) of four patients on prophylaxis received in-home therapy, whereas the others (75%) abandoned prophylaxis. It seems that COVID-19 infection has great consequences on the lives of patients with CBDs, causing some to take dangerous actions, such as abandonment of their treatment. Healthcare systems, and healthcare providers, should have an appropriate strategy for management of patients with CBDs that prevents infection and provides timely replacement therapy

Von Willebrand factor neutralizing and non-neutralizing alloantibodies in 213 subjects with type 3 von Willebrand disease enrolled in 3WINTERS-IPS

BackgroundType 3 von Willebrand disease (VWD) is the most severe form of this disease owing to the almost complete deficiency of von Willebrand factor (VWF). Replacement therapy with plasma-derived products containing VWF or recombinant VWF rarely cause the development of alloantibodies against VWF that may be accompanied by anaphylactic reactions.ObjectiveThe objective of this study was to assess the prevalence of anti-VWF alloantibodies in subjects with type 3 VWD enrolled in the 3WINTERS-IPS.MethodsAn indirect in-house enzyme-linked immunosorbent assay has been used to test all the alloantibodies against VWF. Neutralizing antibodies (inhibitors) have been tested with a Bethesda-based method by using a VWF collagen binding (VWF:CB) assay. Samples positive for anti-VWF antibodies were further tested with Bethesda-based methods by using the semiautomated gain-of-function glycoprotein-Ib binding (VWF:GPIbM) and a VWF antigen (VWF:Ag) enzyme-linked immunosorbent assay.ResultsIn total, 18 of the 213 (8.4%) subjects tested positive for anti-VWF antibodies and 13 of 213 (6%) had VWF:CB inhibitors. These 13 were among the 18 with anti-VWF antibodies. Of the 5 without VWF:CB inhibitors, 3 had non-neutralizing antibodies, 1 only inhibitor against VWF:GPIbM, and one could not be tested further. Ten of the 13 subjects with VWF:CB inhibitors also had VWF:GPIbM inhibitors, 6 of whom also had VWF:Ag inhibitors. Subjects with inhibitors were homozygous for VWF null alleles (11/14), homozygous for a missense variant (1/14), or partially characterized (2/14).ConclusionsAnti-VWF antibodies were found in 8.4% of subjects with type 3 VWD, whereas neutralizing VWF inhibitors were found in 6%, mainly in subjects homozygous for VWF null alleles. Because inhibitors may be directed toward different VWF epitopes, their detection is dependent on the assay used.Thrombosis and Hemostasi

Genotypes of European and Iranian patients with type 3 von Willebrand disease enrolled in 3WINTERS-IPS

Type 3 von Willebrand disease (VWD3) is a rare and severe bleeding disorder characterized by often undetectable von Willebrand factor (VWF) plasma levels, a recessive inheritance pattern, and heterogeneous genotype. The objective of this study was to identify the VWF defects in 265 European and Iranian patients with VWD3 enrolled in 3WINTERS-IPS (Type 3 Von Willebrand International Registries Inhibitor Prospective Study). All analyses were performed in centralized laboratories. The VWF genotype was studied in 231 patients with available DNA (121 [115 families] from Europe [EU], and 110 [91 families] from Iran [IR]). Among 206 unrelated patients, 134 were homozygous (EU/IR - 57/77) and 50 were compound heterozygous (EU/IR - 43/7) for VWF variants. In 22 patients, no or only one variant was found. A total of 154 different VWF variants (EU/IR - 101/58 [5 shared]) were identified among the 379 affected alleles (EU/IR - 210/169), of which 48 (EU/IR - 18/30) were novel. The variants p.Arg1659*, p.Arg1853*, p.Arg2535*, p.Cys275Ser, and delEx1_Ex5 were found in both European and Iranian VWD3 patients. Sixty variants were identified only in a single allele (EU/IR = 50/10), whereas 18 were recurrent (>= 3 patients) within 144 affected alleles. Nine large deletions and one large insertion were found. Although most variants predicted null alleles, 21% of patients carried at least 1 missense variant. VWD3 genotype was more heterogeneous in the European population than in the Iranian population, with nearly twice as many different variants. A higher number of novel variants were found in the Iranian VWD3 patients.Thrombosis and Hemostasi