The burden and management of FXIII deficiency

Clinical Profile of Congenital Factor XIII Deficiency in Children

OBJECTIVES

Congenital Factor 13 Deficiency (FXIIID) is a rare bleeding disorder (RBD) of autosomal recessive inheritance, with an incidence of 1 in 3-5 million. The clinical symptomatology, diagnosis, and management of FXIIID are described.

METHODS

A retrospective chart review of children with FXIIID was performed from January 2000 through October 2021 at a tertiary care center in Southern India. The diagnosis was performed by the Urea clot solubility test (UCST) and Factor XIII antigen assay.

RESULTS

Twenty children (representing 16 families) were included. Male: Female ratio was 1.5:1. The median age of symptom onset was 6 mo, and the median age of diagnosis was 1 y, demonstrating a delay in diagnosis. Consanguinity was present in 15 (75%) with 4 children having affected siblings. Clinical symptomatology ranged from mucosal bleeds to intracranial bleeds and hemarthrosis, with many children having a history of prolonged umbilical bleeding in their neonatal period. Fourteen children were on cryoprecipitate prophylaxis. Four children had breakthrough bleeds due to irregular prophylaxis, including one intracranial bleed due to a delay in cryoprecipitate prophylaxis during the covid pandemic.

CONCLUSIONS

Congenital FXIIID presents with a wide range of bleeding manifestations. The high prevalence of consanguinity in Southern India can be a cause of FXIIID's high prevalence in this region. There is a propensity for intracranial bleeding with a significant number having this at first presentation. Regular prophylaxis is required and feasible to prevent potentially fatal bleeds.

High incidence of intracranial haemorrhage in Egyptian children with congenital afibrinogenaemia

INTRODUCTION

Intracerebral hemorrhage (ICH) is associated with high morbidity and mortality in patients with congenital afibrinogenaemia. Details on location of cerebral haemorrhage, management and neurological outcomes are lacking.

METHODS

We performed a retrospective study on Egyptian children with congenital afibrinogenaemia who experienced ICH, in order to estimate frequency, symptoms and neurological outcomes.

RESULTS

Among 58 children with congenital afibrinogenaemia treated on demand, 18 (31%) had an history of ICH (28 episodes). The first ICH occurred at a median age of 1 year (Q1-Q3 1-7 years). Impaired consciousness level, vomiting and seizures were the most common presenting symptoms. Spontaneous bleeding was associated with a more severe clinical presentation and worse neurological outcomes, including hydrocephaly and impaired cognitive development. Only half of ICH events (n = 14) were treated in less than 24 h from the onset of symptoms. Fibrinogen replacement by Fresh Frozen Plasma (FFP), cryoprecipitate or fibrinogen concentrates was administered in seven (25%), 19 (68%) and three (10%) ICH events, respectively. Overall, seven (25%) ICH occurring in four patients required a surgical intervention. After the ICH, six patients started secondary prophylaxis. The cumulative incidence of ICH at 10 years was 35% (95% CI 23-51) and at 20 years was 40% (95 CI% 26.7-58.8).

CONCLUSION

In our cohort of children with congenital afibrinogenaemia, ICH was very frequent and associated with adverse neurological outcomes and death. Further studies are required to determine whether primary prophylaxis starting early in childhood is indicated after diagnosis.

Gastrointestinal Bleeding in Congenital Bleeding Disorders

Gastrointestinal bleeding (GIB) is serious, intractable, and potentially life-threatening condition. There is considerable heterogeneity in GIB phenotypes among congenital bleeding disorders (CBDs), making GIB difficult to manage. Although GIB is rarely encountered in CBDs, its severity in some patients makes the need for a comprehensive and precise assessment of underlying factors and management approaches imperative. Initial evaluation of GIB begins with assessment of hematological status; GIB should be ruled out in patients with chronic anemia, and in presentations that include hematemesis, hematochezia, or melena. High-risk patients with recurrent GIB require urgent interventions such as replacement therapy for treatment of coagulation factor deficiency (CFD). However, the best management strategy for CFD-related bleeding remains controversial. While several investigations have identified CBDs as potential risk factors for GIB, research has focused on assessing the risks for individual factor deficiencies and other CBDs. This review highlights recent findings on the prevalence, management strategies, and alternative therapies of GIB related to CFDs, and platelet disorders.

Novel deep intronic mutation in the coagulation factor XIII a chain gene leading to unexpected RNA splicing in a patient with factor XIII deficiency

Background

Coagulation factor XIII (FXIII) plays an essential role in maintaining hemostasis by crosslinking fibrin. Deficiency in FXIII affects clot stability and increases the risk of severe bleeding. Congenital FXIII deficiency is a rare disease. Recently, we identified a Chinese family with FXIII deficiency and investigated the pathogenesis of congenital FXIII deficiency, contributing non-coding pathogenic variants.

Methods

We performed common tests, coding sequencing by targeted next-generation sequencing (NGS), whole-genome sequencing and splice-sites prediction algorithms. The pathogenesis was investigated via minigene and nonsense-mediated mRNA decay (NMD) by experiments in vitro.

Results

The proband is homozygote for a novel deep intronic c.799-12G > A mutation in the F13A1 gene. Through direct sequencing of the minigenes mRNA, we found 10 bases of intron 6 insert in the mRNA of mutant minigenes mRNA. The relative expression of EGFP-F13A1 was higher by suppression of NMD in vitro. Furthermore, we found the proband with enhanced thrombin generation (TG).

Conclusion

We reported a novel deep intronic c.799-12G > A mutation of F13A1 which produced a new acceptor site and frame shifting during translation introducing a premature termination codon. Our results support the premature termination codon triggered NMD. We need to pay attention to the position of potential alterable splicing sites while counselling and genetic test. The finding of enhanced TG indicated that we should be aware of the risk of thrombosis in patients with FXIII deficiency during replacement therapy.

Recombinant factor XIII A-subunit in a patient with factor XIII deficiency and recurrent pregnancy loss

Essentials Inherited factor XIII deficiency is a very rare bleeding disorder. We used recombinant factor XIII-A in a pregnant patient with factor XIII-A subunit deficiency. The patient had a successful pregnancy outcome with no pregnancy related complications. The dose of recombinant factor XIII-A was minimized by using frequent trough level monitoring.

SUMMARY

Inherited factor XIII deficiency is a very rare bleeding disorder, and is one of the causes of recurrent pregnancy loss. The use of plasma-derived FXIII to improve pregnancy outcomes has been reported. We report a 26-year-old woman with FXIII A-subunit (FXIII-A) deficiency who was treated with recombinant FXIII-A and had a successful pregnancy outcome with no pregnancy-related complications. Our case illustrates that the dose of recombinant FXIII-A can be minimized and adjusted on the basis of frequent trough level monitoring.

Intracranial haemorrhage in children with inherited bleeding disorders in the UK 2003-2015: A national cohort study

INTRODUCTION

Intracranial haemorrhage in children with inherited bleeding disorders is a potentially life-threatening complication and presents a significant therapeutic challenge.

AIM

To define the characteristics, management and outcomes of intracranial haemorrhage presenting in UK children ≤16 years of age with inherited bleeding disorders from 2003 to 2015.

METHOD

Retrospective analysis of children treated at UK haemophilia centres.

RESULTS

Of 66 children presenting with Intracranial haemorrhage (ICH), 82% had haemophilia A or B, 3% VWD and 15% a rare IBD. The IBD was a severe phenotype in 91%. The rates of ICH were 6.4 and 4.2 per 1000 patient years for haemophilia A and B, respectively. Median age at presentation was 4 months (33% neonates; 91% children <2 years of age). In neonates, delivery was spontaneous vaginal (SV) in 11, instrumental in 6, caesarean in 4 and unknown in 1. In children with haemophilia, the risk of ICH after instrumental delivery was 10.6 times greater than after SV delivery. Trauma was more common in children >2 years (67%) than in children 1 month to 2 years (18%; P = .027). Prior to ICH, only 4.5% of children were on prophylaxis. 6% of haemophiliacs had an inhibitor. The median duration of initial replacement therapy was 15 days. Mortality was 13.5%. Neurological sequelae occurred in 39% of survivors, being more common following intracerebral bleeding. In haemophilia survivors, 52% subsequently developed a FVIII inhibitor.

CONCLUSION

Intracranial haemorrhage occurs most frequently in children with severe IBDs, during the first 2 years of life and in children not receiving prophylaxis. Intracranial haemorrhage often occurs without documented trauma.

Factor XIII deficiency diagnosis: Challenges and tools

Factor XIII deficiency (FXIIID) is a rare hereditary bleeding disorder arising from heterogeneous mutations, which can lead to life-threatening hemorrhage. The diagnosis of FXIIID is challenging due to normal standard coagulation assays requiring specific FXIII assays for diagnosis, which is especially difficult in developing countries. This report presents an overview of FXIIID diagnosis and laboratory methods and suggests an algorithm to improve diagnostic efficiency and prevent missed or delayed FXIIID diagnosis. Assays measuring FXIII activity: The currently available assays utilized to diagnose FXIIID, including an overview of their complexity, reliability, sensitivity, and specificity, as well as mutational analysis are reviewed. The use of a FXIII inhibitor assay is described. Diagnostic tools in FXIIID: Many laboratories are not equipped with quantitative FXIII activity assays, and if available, limitations in lower activity ranges are important to consider. Clot solubility tests are not standardized, have a low sensitivity, and are therefore not recommended as routine screening test; however, they are the first screening test in almost all coagulation laboratories in developing countries. To minimize the number of patients with undiagnosed FXIIID, test quality should be improved in less well-equipped laboratories. Common country-specific mutations may facilitate diagnosis through targeted genetic analysis in reference laboratories in suspected cases. However, genetic analysis may not be feasible in every country and may miss spontaneous mutations. Centralized FXIII activity measurements should also be considered. An algorithm for diagnosis of FXIIID including different approaches dependent upon laboratory capability is proposed.

Social/economic costs and quality of life in patients with haemophilia in Europe

OBJECTIVE

The aim of this study was to determine the economic burden from a societal perspective and the health-related quality of life (HRQOL) of patients with haemophilia in Europe.

METHODS

We conducted a cross-sectional study of patients with haemophilia from Bulgaria, France, Germany, Hungary, Italy, Spain Sweden and the UK. Data on demographic characteristics, health resource utilisation, informal care, loss of labour productivity and HRQOL were collected from the questionnaires completed by patients or their caregivers. HRQOL was measured with the EuroQol 5-domain (EQ-5D) questionnaire. The costs have been estimated from a societal perspective adopting a bottom-up approach.

RESULTS

A total of 401 questionnaires were included in the study, of which 339 were collected from patients with haemophilia and 62 from caregivers. The lowest average annual cost per person was reported in Bulgaria (€6,660) and the highest in Germany (€194,490). Our results demonstrate both a large difference from country to country in the average annual cost per patient in 2012 and the driving role of drugs in costs. Drugs represent nearly 90 % of direct healthcare costs in a majority of the countries analysed (Hungary, Italy, Spain and Germany). In Bulgaria, France and Sweden, however, healthcare services (visits, tests and hospitalisations) prevail. Costs are also shown to differ between children and adults. The mean EQ-5D index score for adult patients was 0.69 and mean EQ-5D VAS was 66.6. The mean EQ-5D index score for carers was 0.87 and mean EQ-5D VAS was 75.5. In the disability score, 60 % showed no disability and measuring caregiver burden with the Zarit Index produced an overall mean score of 25.3.

CONCLUSION

We have shown that haemophilia is associated with a substantial economic burden and impaired HRQOL. Studies on cost of illness and HRQOL are important for haemophilia as the future of this disease is likely to change with the development of new innovative treatments. The introduction of these treatments will most likely impact future costs related to haemophilia.