Genotype and phenotype correlation in intracranial hemorrhage in neonatal factor VII deficiency among Thai children

Molecular spectrum of inherited FVII deficiency in North India revealed a recurrent variant with a founder effect

INTRODUCTION

Inherited Factor VII (FVII) deficiency is commonest among the rare bleeding disorders. A small number of patients present in infancy with severe bleeding, and many may remain asymptomatic but detected before surgery/invasive procedures. Genetic testing may be helpful in predictive testing/prenatal diagnosis in severe cases.

AIM

Characterisation of clinical and genotypic spectrum of patients with inherited FVII deficiency.

METHODS

Retro-prospectively, 35 cases with prolonged prothrombin time and FVII activity (FVII:C) <50 IU/dl were subjected to targeted resequencing. After in-silico analysis, variant/s were validated by Sanger sequencing in index cases and family members. Haplotype analysis was done for F7 polymorphisms.

RESULTS

Severe FVII deficiency was found in 50% of patients (FVII:C ≤1 IU/dl), and 42.9% were asymptomatic. Clinical severity assessment revealed 17% severe, 17% moderate and 22.9% patients with mild bleeds. FVII levels ranged from .3 to 38 IU/dl. Molecular analysis revealed variants in 30/35 cases, of which 17 were homozygous, 10 were compound heterozygous and 3 were heterozygous. Twelve genetic variants were identified, one promoter variant c.-30A>C; seven missense (c.215C>G, c.244T>C, c.253G>C, c.904G>A, c.961C>T, c.1109G>T, c.1211G>A), two deletions (c.21delG, c.868_870delATC), and one each of nonsense c.634C>T and splice-site variant c.316+1G>A. Recurrent variants c.1109G>T and c.215C>G were found in 17 and 8 cases, 12 of the former cases were homozygous. They had the same haplotype, indicating the founder effect in North Indians.

CONCLUSION

This is the largest cohort of FVII genotyping from India, confirming heterogeneity in terms of clinical manifestations, FVII activity and zygosity of the variants with a limited genotypic phenotypic correlation.

Risk and Management of Intracerebral Hemorrhage in Patients with Bleeding Disorders

Intracerebral hemorrhage (ICH) is the most dreaded complication, and the main cause of death, in patients with congenital bleeding disorders. ICH can occur in all congenital bleeding disorders, ranging from mild, like some platelet function disorders, to severe disorders such as hemophilia A, which can cause catastrophic hemorrhage. While extremely rare in mild bleeding disorders, ICH is common in severe coagulation factor (F) XIII deficiency. ICH can be spontaneous or trauma-related. Spontaneous ICH occurs more often in adults, while trauma-related ICH is more prevalent in children. Risk factors that can affect the occurrence of ICH include the type of bleeding disorder and its severity, genotype and genetic polymorphisms, type of delivery, and sports and other activities. Patients with hemophilia A; afibrinogenemia; FXIII, FX, and FVII deficiencies; and type 3 von Willebrand disease are more susceptible than those with mild platelet function disorders, FV, FXI, combined FV-FVIII deficiencies, and type 1 von Willebrand disease. Generally, the more severe the disorder, the more likely the occurrence of ICH. Contact sports and activities can provoke ICH, while safe and noncontact sports present more benefit than danger. An important risk factor is stressful delivery, whether it is prolonged or by vacuum extraction. These should be avoided in patients with congenital bleeding disorders. Familiarity with all risk factors of ICH can help prevent occurrence of this diathesis and reduce related morbidity and mortality.

Identification of two novel mutations in three children with congenital factor VII deficiency

Congenital factor VII deficiency (FVIID) is a rare F7 gene mutation causing bleeding disorder inherited in an autosomal recessive manner. In this study, we aimed to identify genetic defects and analyze their relationships with phenotype in three Chinese FVIID patients. The diagnosis of FVIID was made based on FVII coagulant activity (FVII:C) levels assessed through prothrombin time assay. Direct sequencing and protein modeling were performed to detect genetic mutations and the resulting protein expression. Patient 1, a 2-year-old girl, presented with mild bleeding and was found to have a FVII:C of 0.2% and a compound heterozygous F7 Cys389Gly/Cys115Arg mutation. Patient 2, a 7-year-old boy, consulted for moderate bleeding and was found to have a FVII:C of 0.8% and a compound heterozygous F7 Thr241Asn/Pro324Leu mutation. Patient 3, a 5-year-old boy who developed a mild bleeding after trauma was found to have a FVII:C of 1.8% and a compound heterozygous F7 Thr241Asn/ IVS5-2A>G mutation. We hereby report three congenital FVIID patients with FVII:C less than 2% and their respective F7 mutations, two of which (F7 Cys115Arg, Pro324Leu) are novel. The molecular model analysis of the two novel mutations F7 Cys115Arg and Pro324Leu respectively indicated impairment of the proper folding of epidermal growth factor 1 domain situated on F7 gene and impairment of the procoagulant function of FVII both leading to the congenital deficiency of FVII.

Accidentally discovered high INR in pregnancy unmasks an inherited factor VII (FVII) deficiency that is paradoxically associated with thrombotic tendency

A 32-year-old multiparous obese woman was referred to our center at 37 weeks of twin gestation. She was referred for birth planning following an accidentally discovered high international normalised ratio (INR) in routine preoperative labs. Her history was significant for recurrent pregnancy-associated deep venous thrombosis as well as two early pregnancy losses. Further work-up revealed transaminitis, mild splenomegaly and high lupus anticoagulant titre. A multidisciplinary team of physicians from the high-risk pregnancy, anaesthesiology, haematology, gastroenterology and hepatology departments put a management plan; it culminated into uncomplicated delivery of the patient by repeated caesarian section. The team was also able to figure out the cause of the patient's high INR that is associated with thrombophilia rather than haemophilia.

Case Report: Factor VII Deficiency Presented With Cephalohematoma After Birth

Introduction: Factor VII deficiency is a rare inherited autosomal recessive bleeding disorder with a global prevalence of 1/500,000. Most cases remain asymptomatic, and cases with severe clinical presentation are rarely reported. Case Presentation: A newborn male with no relevant maternal antenatal history, delivered via vacuum-assisted cesarean section, presented with a large cephalohematoma after delivery. Poor appetite, pale appearance, and bulging fontanelles were observed 2 days later, progressing to hypovolemic shock. Further imaging examination revealed a large intracranial hemorrhage. Serial laboratory examination revealed remarkable coagulopathy with prolonged prothrombin time and factor VII deficiency (<1%, severe type). The patient was genetically confirmed to have the FVII:c 681+1 G>T homozygous mutation. Brain hemorrhage was resolved with high-dose factor VII replacement therapy with recombinant activated factor VII. However, repeated hemothorax and intracranial hemorrhage were detected. Therefore, the patient was under regular factor VII supplementation with a rehabilitation program for cerebral palsy. Conclusions: A case of factor VII deficiency with large cephalohematoma and intracranial hemorrhage after birth is described herein, which was treated with high-dose replacement therapy. Variants of the FVII:c 681+1 G>T (IVS6+1G>T) homozygous genotype may present with a severe phenotype at the neonatal stage. We aim to share a unique neonatal presentation with a certain genotype and treatment experience with initial replacement therapy, followed by regular prophylactic dosage.

Novel IVS7+1G>T mutation of life-threatening congenital factor VII deficiency in neonates: A retrospective study in China

In neonates, congenital factor VII deficiency (FVIID) is characterized by central nervous system bleeding and gastrointestinal hemorrhage, often resulting in poor prognosis and high mortality.To improve understanding of FVIID in neonates in Asia, we retrospectively analyzed the clinical manifestations, diagnosis, treatment, clinical course, and genetic diagnosis of 2 cases of neonatal FVIID in the Department of Neonatology, Guangzhou Women and Children's Medical Center, Guangzhou, China, from January 2007 to December 2017 and performed a review of the relevant literature.Both neonates were female and presented with severe gastrointestinal tract and intracranial hemorrhage. The laboratory findings were characterized by repeated and non-vitamin K1-dependent prolonged of the prothrombin time (PT), Factor VII (FVII) activity was 1.5% and 3%, respectively. Both neonates died of severe intracranial hemorrhage, at 31 days and 6 months after birth, respectively. Gene sequencing results revealed a homozygous mutation in the FVII gene splice site (IVS7+1G>T) in both cases. Upon review of relevant literature published since 1996, we identified 19 cases of neonatal FVIID. The patients were full-term neonates with onset of symptoms mostly within 7 days after birth (73.7%), which included gastrointestinal bleeding (blood stool, vomiting blood; 31.6%), nervous system signs (drowsiness, convulsions, poor response; 26.3%), severe intracranial hemorrhage (84.2%), significantly prolonged PT with significantly decreased FVII activity (89.5%), high mortality, and disability (68.4%). Gene sequencing was performed in 9 of the 19 children evaluated and revealed a mutation in the FVII gene in all cases.FVIID can be clinically diagnosed based on the presence of prolonged PT that is difficult to correct and significantly decreased FVII activity (≤5%). As mutations in some sites are associated with severe bleeding, genetic diagnosis represents a useful tool for prenatal diagnosis of FVIID. In brief, we should pay great attention to the FVIID onset of the neonatal period, although it is rare but result in life-threatening bleeding with poor prognosis.

Factor VII Gene Defects: Review of Functional Studies and Their Clinical Implications

Coagulation factors belong to a family of plasma glycosylated proteins that should be activated for appropriate blood coagulation. Congenital deficiencies of these factors cause inheritable hemorrhagic diseases. Factor VII (FVII) deficiency is a rare bleeding disorder with variable clinical symptoms. Various mutations have been identified throughout the F7 gene and can affect all the protein domains. The results of previous experiments have partly revealed the correlation between genotype and phenotype in patients with FVII deficiency. Nevertheless, each particular variant may affect the coagulative function of FVII, mainly via altering its expression level, extra-cellular secretion, tissue factor binding affinity, or proteolytic activity. The pathogenicity of the variants and molecular mechanisms responsible for clinical symptoms in patients with FVII deficiency should be characterized via in silico and in vitro, as well as in vivo functional studies. This review has highlighted the most important functional studies reported on F7 gene variants, including relevant reports regarding Iranian FVII deficiency patients.

Homozygous congenital factor VII deficiency with a novel mutation, associated with severe spontaneous intracranial bleeding in a neonate

OBJECTIVE

Herein, a neonate with congenital FVII deficiency is presented.

BASIC METHOD

Diagnosis of congenital FVII deficiency was confirmed by genetic analysis using next-generation sequencing method (MiSeq-Illumina).

RESULT

Our patient was found to have a novel homozygous mutation.

CONCLUSION

Early diagnosis and treatment of congenital FVII deficiency can be crucial.