Related Experiment Video

Updated: Sep 27, 2026

The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well
08:01

The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well

Published on: February 27, 2026

Haemophilia and thrombophilia. What do we learn about combined inheritance of both genetic variations?

U Nowak-Göttl1, C Escuriola, K Kurnik

  • 1Pediatric Hematology/Oncology, University of Münster, Albert-Schweitzer-Str. 33, 48149 Münster, Germany. leagottl@uni-muenster.de

Hamostaseologie
|February 5, 2003
PubMed

Insights

Prothrombotic risk factors in children with severe hemophilia A (HA) influence clinical outcomes. Children with these factors experienced their first bleeding symptoms later, indicating a complex interplay between bleeding and clotting disorders.

Area of Science:

  • Pediatric Hematology
  • Thrombosis and Hemostasis

Background:

  • Severe hemophilia A (HA) is a bleeding disorder.
  • Prothrombotic risk factors are genetic and acquired conditions that increase the risk of blood clots.

Purpose of the Study:

  • To investigate the prevalence of prothrombotic risk factors in pediatric patients with hemophilia A.
  • To determine the impact of these risk factors on the clinical presentation and outcomes of severe HA in children.

Main Methods:

  • A multicenter cohort study involving 135 pediatric patients with hemophilia.
  • Analysis of factor VIII activity, factor V (FV) G1691A mutation, factor II (FII) G20210A variant, methylenetetrahydrofolate reductase (MTHFR) T677T genotype, elevated lipoprotein a (Lp a), antithrombin, protein C, and protein S.
  • Comparison of the age of first symptomatic bleeding between children with and without prothrombotic risk factors.

Main Results:

  • Prevalence of prothrombotic risk factors in severe HA patients was similar to general population data.
  • Children with severe HA carrying prothrombotic risk factors had a later onset of first symptomatic bleeding (median 1.6 years) compared to non-carriers (median 0.9 years).
  • Two cases of neonatal stroke with hemorrhagic transformation were observed in patients with elevated Lp a and FII GA variant.
  • Catheter-related thrombosis occurred in 8 out of 25 children with central lines during Factor VIII concentrate administration.

Conclusions:

  • The clinical phenotype of severe hemophilia A in childhood is influenced by the coinheritance of prothrombotic risk factors.
  • Coinherited prothrombotic factors may modify the bleeding phenotype and increase the risk of thrombotic events in pediatric hemophilia A patients.
Abstract

More Related Videos

Constitutive and Inducible Systems for Genetic In Vivo Modification of Mouse Hepatocytes Using Hydrodynamic Tail Vein Injection09:35

Constitutive and Inducible Systems for Genetic In Vivo Modification of Mouse Hepatocytes Using Hydrodynamic Tail Vein Injection

Published on: February 2, 2018

Related Concept Videos

Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
Disorders of Hemostasis01:24

Disorders of Hemostasis

Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Pedigree Analysis02:21

Pedigree Analysis

A pedigree is a diagram displaying a family’s history of a trait. Analyzing pedigrees can reveal (1) whether a trait is dominant or recessive, (2) the type of chromosome, autosomal or sex, a trait is linked to, (3) genotypes of family members, and (4) probabilities of phenotypes in future generations. For families with a history of autosomal or sex-linked diseases, this information can be crucial to family planning.Pedigrees Display Family HistoriesIn various plant and animal species,...
Multiple Allele Traits02:19

Multiple Allele Traits

For the same gene multiple alleles can interact to influence phenotypes like the shape and protein composition of an individual cells.By studying allele interactions on the molecular and cellular levels researchers can understand the resulting phenotypes and complications of human conditions like sickle cell trait, improving treatment.The ABO blood group system is a common example of multiple alleles in humans. This system includes three alleles called IA, IB, and i alleles, which combine in...
Multiple Allele Traits02:19

Multiple Allele Traits

For the same gene multiple alleles can interact to influence phenotypes like the shape and protein composition of an individual cells.By studying allele interactions on the molecular and cellular levels researchers can understand the resulting phenotypes and complications of human conditions like sickle cell trait, improving treatment.The ABO blood group system is a common example of multiple alleles in humans. This system includes three alleles called IA, IB, and i alleles, which combine in...
X-linked Traits01:19

X-linked Traits

In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be masked by the presence of a normal allele on the second X. In contrast, a mutation on the X chromosome in males more often causes observable biological defects, as there is no normal X to compensate. Trait variations arising from mutations on the X chromosome are called “X-linked”.